Antibody-drug conjugate and use thereof

Abstract

The present invention relates to an antibody-drug conjugate, and in particular, to an antibody-drug conjugate (ADC) carrying a Ras mutation inhibitor, a composition comprising the ADC molecule, and therapeutic use thereof.

Description

Technical Field The present disclosure relates to antibody-drug conjugates (ADCs) based on Ras mutation inhibitors, pharmaceutical compositions comprising the same, and methods for their use in treating or preventing diseases associated with Ras mutations. Specifically, the present disclosure relates to compounds, uses, and methods for treating or preventing related diseases such as tumors or cancers by targeting oncogenic mutants of Ras. Background Technology Ras belongs to the GTPase protein family. Under normal physiological conditions, Ras is activated by growth factors and various other extracellular signals and is responsible for regulating functions such as cell growth, survival, migration, and differentiation. These regulatory functions of Ras are carried out through the transition between an inactive GDP-bound state and an active GTP-bound state, i.e., a "molecular switch". GDP-bound Ras is an inactive form that is activated when exposed to several pro-growth stimuli, such as guanine nucleotide exchange factor (GEF), releasing GDP and binding to GTP, thereby converting to an active GTP-bound state, which recruits and activates various downstream effectors for signal transmission, thereby controlling numerous critical cellular processes such as differentiation, survival, and proliferation. Ras has GTPase activity; it can cleave the terminal phosphate of GTP to convert it to GDP, thereby converting itself to an inactive state. However, the intrinsic GTPase activity of Ras is very low. Converting GTP-Ras to GDP-Ras requires exogenous protein GAP (GTPase-activating protein). GAP interacts with Ras and promotes the conversion of GTP to GDP. Therefore, any Ras gene mutation that affects the interaction between Ras and GAP or the conversion of GTP to GDP will lead to Ras being in an over-activated state, thereby continuously transmitting growth and division signals to cells, stimulating continuous cell proliferation, and ultimately leading to tumor formation and development. Indeed, dysregulation of the Ras signaling pathway is almost always associated with disease. Hyperactivating somatic mutations in Ras are among the most common lesions in human cancers. Although mutations in any of the three Ras isoforms (K-Ras, N-Ras, or H-Ras) have been shown to result in oncogenic transformation, KRas mutations are by far the most common mutations in human cancers, which are common in pancreatic cancer, lung adenocarcinoma, colorectal cancer, gallbladder cancer, thyroid cancer, and cholangiocarcinoma, and can also be found in 25% of patients with non-small cell lung cancer. Most KRas mutations occur at codons G12, G13 and Q61, and about 80% of KRas mutations occur at glycine at codon 12, such as G12C mutation, G12D mutation, G12V mutation, G12A mutation, G12R mutation, G12S mutation and G13D mutation, of which G12D mutation is one of the most common mutations. In view of this, Ras mutant proteins, such as KRas mutant proteins, have become very attractive anti-cancer drug targets in the pharmaceutical field, and the development of their inhibitors is also regarded as a very promising R & D direction in anti-cancer / oncology drug development. However, drug research and development for K-Ras mutations in the past decades has shown that existing small molecule inhibitors of K-Ras mutations have many insurmountable defects, such as inability to effectively deliver to some lesions such as the colon, breast and pancreas, severe drug resistance, poor membrane permeability, poor hydrophilicity, poor oral pharmacokinetics, and high intravenous toxicity, so KRas has even long been considered as an "incurable" target. Therefore, the inventor has been dedicated to the development of small molecule inhibitors of Ras, e.g. KRas mutations with improved structural patterns that have been shown to have enhanced Ras, e.g. KRas mutation inhibitory activity and inhibitory activity against related tumors compared to existing technologies Ras, e.g. KRas mutation inhibitors, due to specifically designed structural fragments, while having good oral pharmacokinetic properties, resulting in good druggability, reduced toxic side effects, improved drug resistance and safety, and reduced risk of drug interactions. Nevertheless, novel therapies that can deliver Ras, e.g. KRas mutant inhibitors site-directed into the tumor environment, can be administered in a more friendly manner, and prolong efficacy, reduce toxic side effects, and drug resistance are urgently needed in the field of cancer treatment. This present disclosure satisfies the above requirements. Targeted conjugated drugs are a new drug delivery technology with high efficiency and low toxicity, which shows strong advantages in anti-cancer drug research and development. Cytotoxic molecules are linked to guide molecules such as antibodies and peptides through suitable linkers, which can highly selectively deliver conjugated molecules to tumor tissues with highly expressed guide receptors, selectively bring anti-cancer drugs into cancer cells through internalization effects, and then excise and release active anti-cancer molecules using differential functional molecules enriched in tumor tissues and cancer cells. Since the active anti-cancer molecule can only be released and enriched inside the tumor tissues with high expression of the guiding receptor and specific "cutters", this dual-selective drug delivery method greatly reduces the toxicity of the anti-cancer drug and improves its efficacy. The inventor uses a targeted conjugation strategy to further link the developed set of Ras, e.g. KRas mutant inhibitor compounds to guide molecules, such as antibodies and peptides, through suitable linkers to prepare a set of ADC compounds based on targeted Ras, e.g. KRas mutant inhibitors. The developed ADC compounds, which are dually selective due to the use of targeted Ras, e.g., K-Ras enzyme inhibitors as ADC loadings, can significantly reduce toxicity; have increased coupling efficiency and product purity due to specific modifications to linker units, inhibit ADC macromolecule aggregation, and improve efficacy; and these ADC macromolecules delay the metabolism of loaded Ras, e.g., KRas mutant inhibitors, thus further improving the system stability and PK properties of the drug, obtaining a long half-life, long-lasting target inhibition, and prolonged efficacy in vivo, thereby delaying the development of drug resistance. Summary of Invention To meet the above needs in the art, the present inventors conducted in-depth research and obtained antibody-drug conjugates as shown in the Examples by conjugating a group of Ras, e.g., KRas mutant, inhibitor compounds with specific structures to guiding molecules through selected linker units. Ras inhibitors currently under development, such as KRas inhibitors, have shown many defects in the development and use process, including inability to effectively deliver to certain lesions, severe drug resistance, poor membrane permeability, poor hydrophilicity, poor oral PK properties, and high intravenous toxicity; while the disclosed antibody drug conjugate, through innovative structural modification of the components of the linker unit of ADC and the first use of this linker unit for conjugation Ras small molecule inhibitors and antibody guiding units, can be rapidly and effectively endocytosed by tumor cells, and shows significant tumor growth inhibition activity and good tolerability compared with antibodies alone and Ras inhibitors alone in animal models, which well overcomes the above defects. It is expected that more mature and friendly administration methods (e.g., oral and parenteral) can be used to provide enhanced and prolonged efficacy, good pharmacokinetic properties, reduced toxic side effects and drug resistance, as well as expanded indications and beneficiary populations. Therefore, in the first aspect, the present disclosure provides an antibody-drug conjugate (ADC) of formula (X) or a pharmaceutically acceptable salt or solvate thereof: [P-L]q-Ab                  (X) wherein, P represents a Ras inhibitor, e.g., a Ras inhibitor as defined in the section on the Drug P unit of the present disclosure (e.g., a compound of formula (I) and its sub-formulas as defined herein); L represents a linker unit connecting P to Ab; q represents the number of [P-L] linking groups connected to Ab, e.g., q = an integer or noninteger from 1 to 20, such as 1-10, 1-8, 2-8, 3-8, 4-8, or 6-8; Ab represents an antibody or antigen-binding fragment. In the second aspect, the present disclosure provides a pharmaceutical composition comprising an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, optionally at least one other therapeutic agent, and optionally one or more pharmaceutically acceptable excipients. In the third aspect, the present disclosure provides an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, or a pharmaceutical composition comprising the same, for use as a therapeutic agent for treating or preventing diseases mediated by Ras mutant proteins (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins), more specifically for use in treating or preventing hyperproliferative diseases, especially as an anti-tumor therapeutic agent. In some specific embodiments, the Ras mutant protein is a KRas mutant protein. In the fourth aspect, the present disclosure provides use of an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, or a pharmaceutical composition comprising the same, in the prevention or treatment of diseases mediated by Ras mutant proteins (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins), more specifically in the treatment or prevention of hyperproliferative diseases, especially tumors. In the fifth aspect, the present disclosure provides a method for treating or preventing a disease mediated by a Ras mutant protein (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins) in a subject, comprising administering to a human or animal an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, or a pharmaceutical composition comprising the same; specifically, the present disclosure provides a method for treating or preventing a hyperproliferative disease, especially a tumor, in a subject, comprising administering to a human or animal an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, or a pharmaceutical composition comprising the same. In the sixth aspect, the present disclosure provides use of an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, or a pharmaceutical composition comprising the same, in the manufacture of a medicament for the prevention or treatment of diseases mediated by Ras mutant proteins (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins); specifically, the present disclosure provides use of an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, or a pharmaceutical composition comprising the same, in the manufacture of a medicament for the treatment or prevention of hyperproliferative diseases, especially tumors. In the seventh aspect, the present disclosure provides a pharmaceutical combination comprising an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, and at least one other therapeutic agent; the combination is for use in the prevention or treatment of diseases mediated by Ras mutant proteins (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins), more specifically in the treatment or prevention of hyperproliferative diseases, especially tumors; and a method for treating or preventing a disease mediated by a Ras mutant protein (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins), more specifically a hyperproliferative disease, especially a tumor, in a subject, comprising administering to a human or animal the pharmaceutical combination of the present disclosure. In the eighth aspect, the present disclosure also provides a method for preparing an ADC of the present disclosure or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof by conjugating a Ras inhibitor as defined herein to an antibody or antigenbinding fragment via a linker unit. The Ras inhibitor compounds defined herein can be conjugated to the antibody or antigen-binding fragment via a cleavable or non-cleavable linker unit. In specific embodiments, upon cleavage of the linker unit, the Ras inhibitor is released into the tumor cell, cancer-associated immune cell, or tumor microenvironment. In some embodiments of various aspects of the present disclosure described above, the Ras mutant protein is a KRas mutant protein, specifically a KRas G12D mutant protein, and correspondingly the P inhibitor compound is a KRas inhibitor, specifically a KRas G12D inhibitor; in other embodiments, the Ras mutant protein is not limited to a specific isoform and / or mutation site, i.e., it is pan-Ras, and correspondingly the P inhibitor compound is a pan-Ras inhibitor. The present disclosure is further illustrated in the following drawings and specific embodiments. However, these drawings and specific embodiments should not be considered as limiting the scope of the present disclosure, and modifications apparent to those skilled in the art are intended to be included within the spirit of the disclosure and the protection scope of the appended claims. Description of Drawings Figure 1 shows the anti-tumor effect and body weight changes of representative ADC compounds of the present disclosure in a subcutaneous xenograft BALB / c Nude mouse model of KRAS-G12D mutant human colon cancer cell GP2D (dose: 20 mg / kg, D0 / 7 days dosing, 21 days). Figure 2 shows the anti-tumor effect and body weight changes of representative ADC compounds of the present disclosure in a subcutaneous xenograft BALB / c Nude mouse model of KRAS-G12D mutant human colon cancer cell GP2D in a separate experiment batch (dose: 10 mg / kg, D0 dosing, 21 days). Figure 3 shows the anti-tumor effect of representative ADC compounds of the present disclosure in a subcutaneous xenograft BALB / c Nude mouse model of KRAS-G12D mutant human colon cancer cell GP2D in a separate experiment batch (dose: 10 mg / kg, D0 dosing, 20 days). Figures 4A, 4B, 4C show results from the same separate experiment batch, i.e., the anti-tumor effect of representative ADC compounds of the present disclosure in a subcutaneous xenograft BALB / c Nude mouse model of KRAS-G12D mutant human colon cancer cell GP2D (dose: 10 mg / kg, D0 dosing, 20 days). For clarity of presentation, the example compounds in this batch experiment are shown separately in Figures 4A, 4B, and 4C. Figures 5 and 6 respectively show the anti-tumor effect of representative ADC compounds of the present disclosure, drug P unit, and antibody in a subcutaneous xenograft BALB / c Nude mouse model of KRAS-G12D mutant human colon cancer cell GP2D in separate experiment batches (dose: 10 mg / kg, D0 and / or 7 and / or 14 days dosing, 21 days). Detailed Description of Invention Definitions Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. For the purposes of the present disclosure, the following terms are defined below. When a trade name is used herein, unless the context indicates otherwise, the trade name includes the product formulation, the generic drug, and the active pharmaceutical ingredient(s) of the trade name product. As used herein, the term "substantially" means the majority, i.e., > about 50% of a population, mixture, sample, content, or any other numerical value, preferably greater than about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%. As used herein, the term "and / or" should be understood to mean any one of the options or any combination of two or more of the options. As used herein, the term "ADC" or "conjugate" refers to an antibody-drug conjugate. As used herein, the term "drug" refers to a substance that produces a beneficial preventive or therapeutic effect on a disease mediated by a Ras mutant protein, e.g., a KRas mutant protein (such as, but not limited to, G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant proteins). As used herein, the term "Ras mutation" or "Ras mutant protein" refers to a protein encoded and expressed by a Ras gene in which one or more codons have undergone mutation, typically including but not limited to Ras proteins with mutations at glycine codon 12, glycine codon 13, or glutamine codon 61 of Ras, such as mutated HRas, NRas, or KRas. These residues are located in the active site of Ras, and their mutations can impair the intrinsic or GAP-catalyzed GTPase activity of Ras, leading to the persistent presence of GTP-bound Ras. For the purposes of the present disclosure, "Ras mutation" or "Ras mutant protein" and "Ras" when describing inhibitory activity are used interchangeably, for example, referring to mutated KRas, such as, but not limited to, KRas-G12C (glycine to cysteine mutation at codon G12), KRas-G12D (glycine to aspartic acid mutation at codon G12), HRas-G12D, NRas-G12D, KRas-G12V (glycine to valine mutation at codon G12), KRas-G13D (glycine to aspartic acid mutation at codon G13); in some embodiments refers to a KRas mutant protein, more particularly to a KRas-G12C mutant protein, KRas-G12D mutant protein, KRas-G12V mutant protein, G12A mutant protein, G12R mutant protein, G12S mutant protein, KRas-G13D mutant protein, most particularly to KRas-G12D; in other embodiments refers to a pan-RAS mutant protein, i.e., not limited to a specific isoform and mutation site. As used herein, the term "Ras mutation-mediated disease" refers to a disease where Ras mutation contributes to the onset and progression of the disease, or where inhibiting Ras mutation will reduce the incidence, or reduce or eliminate the symptoms of the disease. For the present disclosure, "Ras mutation-mediated disease" in some embodiments refers to a KRas mutation-mediated disease, most preferably KRas-G12D; in other embodiments refers to a pan-Ras-mediated disease, such as a hyperproliferative disease like cancer or tumor. As used herein, the term "cancer" or "tumor" refers to abnormal cell growth and proliferation, including solid tumors and hematological tumors, whether malignant or benign, and all precancerous and cancer cells and tissues. For various aspects of the present disclosure, the cancer or tumor includes, but is not limited to, lung adenocarcinoma, lung cancer (including lung squamous cell carcinoma and non-small cell lung cancer, small cell lung cancer (SCLC)), bone cancer, pancreatic cancer, pancreatic ductal adenocarcinoma, skin cancer, head and neck cancer (including head and neck squamous cell carcinoma), melanoma (including cutaneous or intraocular melanoma), squamous cell carcinoma, anal region cancer, testicular cancer, urethral cancer, penile cancer, prostate cancer (including hormone-refractory prostate cancer), bladder cancer, uterine cancer, ovarian cancer, ovarian epithelial cancer, fallopian tube cancer, endometrial cancer, cervical cancer, vaginal cancer, vulvar cancer, gastric cancer, gastric adenocarcinoma, colon cancer, rectal cancer, colorectal cancer, liver cancer, breast cancer (including metastatic breast cancer, triple-negative breast cancer (TNBC)), esophageal cancer, small intestine cancer, lip cancer, laryngeal cancer, nasopharyngeal cancer, oral cancer, salivary gland cancer, peritoneal cancer, gastrointestinal stromal tumor, gastroesophageal junction (GEJ) cancer, mesothelioma, biliary tract cancer, hepatocellular carcinoma, seminoma, soft tissue sarcoma, osteosarcoma, urothelial carcinoma, sweat gland carcinoma, endocrine system cancer, thyroid cancer, medullary thyroid cancer, follicular thyroid cancer, papillary thyroid cancer, parathyroid cancer, kidney cancer, renal parenchymal cancer, renal cell carcinoma, renal pelvic cancer, adrenal cancer, brain cancer such as glioblastoma, astrocytoma, meningioma, medulloblastoma, peripheral neuroectodermal tumor, glioblastoma (including glioblastoma multiforme), neuroblastoma; chronic or acute leukemia, Hodgkin's disease, lymphoma (including lymphocytic lymphoma, Hodgkin lymphoma, non-Hodgkin lymphoma, Burkitt lymphoma, adult T-cell lymphoma, diffuse large B-cell lymphoma (DLBCL), primary CNS lymphoma), acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CLL) and lymphocytic carcinoma, acute myeloid leukemia (AML), myeloid leukemia (chronic myeloid leukemia (CML)), central nervous system (CNS) tumors, spinal tumors, brainstem glioma, or pituitary adenoma. For various aspects of the present disclosure, preferably, the cancer or tumor is associated with a Ras mutation, e.g., a KRas mutation, including but not limited to the above tumor types and their preferred ranges. Particularly preferred tumors of the present invention include lung cancer, lung adenocarcinoma, colon cancer, rectal cancer, pancreatic cancer, endometrial cancer, cholangiocarcinoma, leukemia, and ovarian cancer. As used herein, the term "anti-tumor effect" refers to a biological effect that can be characterized in various forms, including, for example, reduction in tumor volume, reduction in the number of tumor cells, reduction in tumor cell proliferation, or reduction in tumor cell survival. As used herein, the term "inhibit" and "reduce" or any variation of these terms refers to the ability of a biologically active agent to reduce the signaling activity of a target of interest by interacting directly or indirectly with the target, and refers to any measurable reduction or complete inhibition of the target activity. For example, compared to normal conditions, the activity (e.g., Ras activity, e.g., KRas activity) can be reduced by about, up to about, or at least about 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99%, or more, or any range derivable therein. As used herein, the term "selectively inhibit" refers to the ability of a biologically active agent to preferentially reduce the signaling activity of a target of interest compared to the signaling activity of an off-target, by interacting directly or indirectly with the target. For the Ras inhibitors and their ADCs of the present disclosure, relative to various mutations occurring at one or more codons of the Ras protein, they have the ability to selectively inhibit G12 or G13 mutations of the KRas protein, such as G12C mutation, G12D mutation, G12V mutation, G12A mutation, G12R mutation, G12S mutation, and G13D mutation, preferably the ability to selectively inhibit the G12D mutation of the KRas protein. For example, compared to another specific Ras mutation, the inhibitory activity of the Ras inhibitors and their ADCs of the present disclosure against a specific mutation such as KRas-G12D is at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, or more, or any range derivable therein, or compared to the activity against another specific Ras mutation, the inhibitory activity against a specific mutation such as KRas-G12D is at least 0.1-, 0.5-, 1-, 2-, 3-, 4-, 5-, 10-, 25-, 50-, 100-, 250-, or 500-fold or higher. As used herein, the term "dual selective inhibition" refers to the ability of the conjugated drug to exert dual selective inhibitory effects by, on the one hand, targeting and inhibiting a specific Ras mutation via the small molecule targeted inhibitor, and on the other hand, utilizing the conjugated guiding antibody molecule to highly selectively deliver the loaded Ras targeted inhibitor to tumor tissues with high expression of the guiding receptor. As used herein, the term "antigen" refers to an entity that specifically binds to an antibody. As used herein, the term "antibody" refers to a polypeptide that comprises at least a light chain or heavy chain immunoglobulin variable region which specifically recognizes and binds an antigen. The term encompasses various antibody structures, including but not limited to monoclonal antibodies, single-chain or multi-chain antibodies, monospecific or multispecific antibodies (e.g., bispecific antibodies), chimeric or humanized antibodies, full-length antibodies, and antibody fragments, as long as they exhibit the desired antigen-binding activity. The antibody can be of any class (e.g., IgG, IgE, IgM, IgD, and IgA), type (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2), or subtype. As used herein, the terms "antibody fragment" and "antigen-binding fragment" of an antibody are used interchangeably and refer to a molecule other than an intact antibody that comprises a portion of an intact antibody that binds the antigen to which the intact antibody binds. As understood by those skilled in the art, for antigen-binding purposes, an antibody fragment typically comprises amino acid residues from a "complementarity determining region" or "CDR". Antibody fragments can be prepared by recombinant DNA techniques or by enzymatic or chemical cleavage of intact antibodies. Antigen-binding fragments include, but are not limited to, Fab, scFab, Fab', F(ab')2, Fab'-SH, Fv, single-chain Fv, diabody, triabody, tetrabody, minibody, single-domain antibody (sdAb); and multispecific antibodies formed from antibody fragments. As used herein, reference to an IgG antibody means that the antibody is a heterotetrameric protein having the structure of an IgG class immunoglobulin. In an IgG antibody, typically the VH-CH1 of the heavy chain pairs with the VL-CL of the light chain to form a Fab fragment that specifically binds antigen. Thus, an IgG antibody essentially consists of two Fab molecules linked by an immunoglobulin hinge region and two dimerized Fc regions. In some embodiments, the IgG antibody is, e.g., an IgG1, IgG2, IgG3, or IgG4 antibody. In other embodiments, the IgG antibody is an IgGK or IgGX antibody, e.g., an IgG1K or IgGIX antibody. As used herein, the terms "complementarity determining region" or "CDR region" or "CDR" or "hypervariable region" are used interchangeably and refer to regions of an antibody variable domain that are hypervariable in sequence and form structurally defined loops ("hypervariable loops") and / or contain antigen-contacting residues ("antigen contact points"). CDRs are primarily responsible for binding to an epitope. As used herein, the CDRs of the antibody heavy and light chains are numbered sequentially from the N-terminus, commonly referred to as CDR1, CDR2, and CDR3. The CDRs located within the antibody heavy chain variable domain are also referred to as HCDR1, HCDR2, and HCDR3, while the CDRs located within the antibody light chain variable domain are referred to as LCDR1, LCDR2, and LCDR3. In a given light chain variable region or heavy chain variable region amino acid sequence, its CDR sequences can be determined using various well-known schemes in the art, including CDR sequences defined based on Kabat, AbM, Chothia, Contact, and IMGT. Furthermore, CDRs can also be determined based on having the same Kabat numbering position as a reference CDR sequence. As used herein, "variable region" or "variable domain" is the domain of an antibody heavy or light chain that is involved in binding the antibody to its antigen. The heavy chain variable region (VH) and light chain variable region (VL) can be further subdivided into hypervariable regions (HVRs, also termed complementarity determining regions (CDRs)) interspersed with more conserved regions (i.e., framework regions (FRs)). Each VH and VL is composed of three CDRs and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. In some aspects, the antibody variable region can be modified by CDR grafting. Since CDR sequences are responsible for most antibody-antigen interactions, it is possible to construct recombinant antibody variants that mimic the properties of a known antibody. In such antibody variants, the CDR sequences from a known antibody are grafted onto the framework regions of a different antibody with different properties. The properties of the mutated and / or modified antibody or ADC conjugate comprising it, such as target antigen binding properties or other desired functional properties, e.g., ADC internalization, pharmacokinetics, and in vivo tumor killing activity, can be assessed in in vitro or in vivo assays. As used herein, the term "isotype" refers to the antibody type determined by the heavy chain constant region. For example, the antibody portion of the ADC according to the present disclosure can be an IgA (e.g., IgA1 or IgA2), IgG1, IgG2 (e.g., IgG2a or IgG2b), IgG3, IgG4, IgE, IgM, and IgD antibody, and have the heavy chain constant region of said immunoglobulin type. Furthermore, the present disclosure contemplates not only antibodies using native sequence constant regions but also antibodies comprising variant sequence constant regions. As used herein, the term "epitope" includes any protein determinant capable of specifically binding to an immunoglobulin or otherwise interacting with a molecule. Epitopic determinants usually consist of chemically active surface groupings of molecules such as amino acids or carbohydrate or sugar side chains and can have specific three-dimensional structural characteristics as well as specific charge characteristics. An epitope can be "linear" or "conformational". Conformational and linear epitopes differ by loss of binding to the former but not the latter in the presence of denaturing solvent. As used herein, the term "receptor-mediated endocytosis" refers to a process triggered by the binding of a ligand to its corresponding receptor on the cell surface, whereby the ligand / receptor complex is internalized and delivered into the cytosol or transferred to an appropriate intracellular compartment. The receptor-mediated endocytosis activity of an antibody can be characterized by measuring the rate of internalization. As used herein, "sequence identity" refers to the extent to which sequences are identical on a nucleotide-by-nucleotide or amino acid-by-amino acid basis over a window of comparison. The "percent sequence identity" can be calculated by: comparing two optimally aligned sequences over a comparison window, determining the number of positions at which the identical nucleic acid base (e.g., A, T, C, G, I) or identical amino acid residue (e.g., Ala, Pro, Ser, Thr, Gly, Val, Leu, Ile, Phe, Tyr, Trp, Lys, Arg, His, Asp, Glu, Asn, Gln, Cys, and Met) occurs in both sequences to yield the number of matched positions, dividing the number of matched positions by the total number of positions in the comparison window (i.e., the window size), and multiplying the result by 100 to yield the percent sequence identity. Optimal alignment for determining percent sequence identity can be achieved in various ways known in the art, for example, using publicly available computer software such as BLAST, BLAST-2, ALIGN, or Megalign (DNASTAR) software. One skilled in the art can determine appropriate parameters for aligning sequences, including any algorithms needed to achieve maximal alignment over the full length of the sequences being compared or over a target sequence region. As used herein, the term "isolated" antibody is one that has been separated from a component of its natural environment. In some embodiments, an antibody is purified to greater than 90%, 95%, or 99% purity as monitored by, for example, electrophoresis (e.g., SDS-PAGE, isoelectric focusing (IEF), capillary electrophoresis) or chromatography (e.g., ion exchange or reverse phase HPLC). As used herein, the term "affinity" or "binding affinity" refers to the intrinsic binding affinity that reflects the interaction between members of a binding pair, e.g., the strength of the interaction between an antibody and an antigen at a single antigenic site; the stronger the interaction, the higher the affinity. The affinity of a molecule for its partner can typically be represented by the equilibrium dissociation constant (KD), which is the ratio of the dissociation rate constant to the association rate constant (kdis and kon, respectively). Affinity can be measured by common methods known in the art, such as antigen protein- or cell-based ELISA assays, flow cytometry assays, Bio-Layer Interferometry (BLI) technology, etc. As used herein, the term "KD" (M) refers herein to the dissociation equilibrium constant of a particular antibody-antigen interaction. Affinity is inversely related to the KD value, i.e., the higher the affinity, the lower the KD value; conversely, the lower the affinity, the higher the KD value. Generally, the KD value depends on the dissociation rate constant (Kd or Kdis, sec-1) and the association rate constant (Ka, M-1 x sec-1) between the interacting antibody-antigen pair. As used herein, the term "binding" or "specifically binding" refers to the ability of a single antibody binding site to react with one antigenic determinant and not with a different antigenic determinant. In the context of an antibody binding to its cognate antigen, it refers to binding with a KD value affinity of about 10-6 M or less, e.g., a KD value of about 10-7 M or less, or about 10-8 M or less. The KD value for binding of an antibody to its cognate antigen is preferably at least 100-fold lower, or for example at least 1000-fold lower, than the KD value for binding to a non-specific antigen (e.g., an unrelated antigen such as BSA). Measurement of KD values is known in the art, for example based on Bio-Layer Interferometry (BLI) technology, determined in an instrument such as the ForteBio Octet® using the antibody as the ligand and the antigen as the analyte. As used herein, the term "effector function" refers to those biological activities attributable to the Fc region of an antibody, which vary with the antibody class. It is known that IgG Fc regions can mediate several important effector functions, such as cytokine induction, ADCC, phagocytosis, complement-dependent cytotoxicity (CDC), and the half-life / clearance rate of antibodies and antigenantibody complexes. In some cases, depending on the therapeutic purpose, these effector functions may be desirable for a therapeutic antibody, but may be unnecessary in other cases. Thus, in one embodiment, the present disclosure provides antibodies having an Fc region that elicits effector functions such as ADCC or CDC, thereby inducing tumor cell apoptosis, cell lysis, and / or inhibiting proliferation, dissemination, and / or metastasis of TF antigen-bearing tumor cells in TF antigenbearing tumor cells. In other embodiments, the present disclosure also provides antibodies having an Fc region with altered effector function. Effector function can be altered by making sequence changes to the Fc region of the antibody. Alternatively, antibodies can be prepared with altered types of glycosylation in the Fc region. Altering the glycosylation pattern of the Fc region can be conveniently achieved by altering the amino acid sequence of the Fc region to create or remove one or more glycosylation sites. As used herein, the term "linker unit" or "linker" refers to a bifunctional moiety that connects the drug to the antibody in an antibody-drug conjugate. The linker unit of the present disclosure has multiple components, such as a self-immolative linker, a cleavable linker, a property-modulating unit, and an antibody linker. As used herein, the term "self-immolative linker" refers to a temporary extender, spacer, or placeholder unit that links two or more molecules together via chemical bonds that break under defined conditions to release the two molecules. Typically, the self-immolative linker unit can be linear or branched and can link two or more identical molecules together, or can link two or more different molecules together. A self-immolative unit can be defined as a bifunctional chemical group capable of covalently linking two spaced-apart chemical moieties together to form a generally stable molecule, releasing one of the spaced-apart chemical moieties from the molecule by enzymatic cleavage; and following said enzymatic cleavage, spontaneously cleaving from the remainder of the bifunctional chemical group to release the other of the spaced-apart chemical moieties. In some examples, a self-immolative unit refers to a heterocyclic self-immolative moiety. Typical self-immolative linker units include, but are not limited to, His-Ala, p-aminobenzyloxycarbonyl (PABC), p-hydroxybenzyloxycarbonyl, 2,4-bis(hydroxymethyl)aniline, -NH(CH2)4-C(O)- and -NH-(CH2)3-C(O)-, etc. As used herein, the term "cleavable linker" refers to a moiety in the linker unit of an ADC that is labile in vivo. Preferably, a "cleavable linker" allows activation of a label or therapeutic agent by cleavage of the label or agent from the remainder of the conjugate. Operationally defined, a cleavable linker is preferably cleaved by the biological environment in vivo. Cleavage can be by any process without limitation, e.g., enzymatic, reductive, pH, etc. Preferably, the cleavable group is selected such that activation occurs at the desired site of action, which can be at or near a target cell (e.g., cancer cell) or tissue, e.g., the site of therapeutic action or label activity. Such cleavage can be enzymatic, and exemplary enzymatically cleavable groups include naturally occurring amino acids or peptide sequences ending with naturally occurring amino acids, and attached at their carboxyl terminus to the linker unit or self-immolative linker. As used herein, the term "antibody linker" refers to any chemical group designed to facilitate attachment of the drug conjugate to the antibody. As used herein, the term "property-modulating unit" refers to a functional moiety linked in series or in a branched manner within the linker unit of the ADC, aimed at modulating the properties of the ADC, such as stability in the bloodstream, improving hydrophilicity, etc. Commonly used propertymodulating units for ADCs include, but are not limited to, polyethylene glycol (PEG), hydrophilic peptides, monosaccharides, oligosaccharides, polysaccharides, cyclodextrin units, polyamines, polyamides, dendrimers, and bifunctional hydrocarbon chains. In the ADC of the present disclosure, the property-modulating unit can be linked as a separate component in series within the linker unit, or as a branch off various components within the linker unit, for example, the property-modulating unit can be linked to the self-immolative linker, the cleavable linker, and / or the antibody linker. As used herein, a specific example of the "property-modulating unit" includes a "solubilizing sugar unit", which refers to a sugar unit attached (directly or indirectly through other structural fragments) to a linker unit, e.g., the self-immolative linker part of the linker. This sugar unit, together with the self-immolative linker, is specifically hydrolyzed in vivo by enzymes such as P-glucuronidase or P-galactosidase, undergoing a self-immolative reaction to release the drug payload. In the antibody-drug conjugates of the present disclosure, introducing a sugar group into the linker unit helps improve the hydrophilicity of the conjugated chain, increases the payload loading rate to the theoretical maximum value, while improving the solubility and purity of the conjugate, reducing aggregation, improving the druggability of the conjugate, and ultimately enhancing the effect of inhibiting tumor cell proliferation. As used herein, as an example of a property-modulating unit, "monosaccharide" refers to a polyhydroxy aldehyde (aldose) or polyhydroxy ketone (ketose) containing 3 or more carbon atoms and their derivatives. They are the basic structural units constituting sugars and their complexes, cannot be further hydrolyzed, and are not linked to other similar units via glycosidic bonds. Depending on the number of carbon atoms, monosaccharides can be divided into three-carbon sugar (triose), four-carbon sugar (tetrose), five-carbon sugar (pentose), six-carbon sugar (hexose), seven-carbon sugar (heptose), etc. The ADCs of the present disclosure preferably carry pentoses or hexoses. Derivatives of said monosaccharides include, for example, phosphate esters of monosaccharides, sugar alcohols, sugar acids, deoxy sugars, amino sugars, acylated amino sugars, and glycosides. Examples of monosaccharides or their derivatives include, but are not limited to, glyceraldehyde, glyceraldehyde phosphate, dihydroxyacetone phosphate, erythrose, erythrulose, threose, arabinose, ribose, ribulose, deoxyribose, ribitol, ribose phosphate, xylose, xylulose, xylitol, lyxose, glucose, glucosamine, acetylglucosamine, glucuronic acid, acetylglucosaminic acid, glucose phosphate, mannose, mannitol, aminomannitol, acetylmannosamine, fructose, fructose phosphate, galactose, galactitol, galactosamine, acetylgalactosamine, allose, deoxyallose, altrose, deoxyaltrose, quinovose, rhamnose, psicose, sorbose, sorbitol, tagatose, gulose, deoxygulose, idose, talose, fucose, deoxytalose, etc. It should be noted that the monosaccharides and their derivatives described in the present disclosure include their D-configuration, L-configuration, racemates (DL), and meso forms, as well as any optically active forms ((+), (-), (±)). The monosaccharides and their derivatives described in the present disclosure include their chain isomers, cyclic isomers, or mixtures thereof, wherein the cyclic forms include a-anomeric forms and P-anomeric forms, and include, for example, pyranose or furanose forms. As used herein, "a disaccharide" as a property-modulating unit refers to a compound formed by linking two monosaccharides via a glycosidic bond, and derivatives thereof. Depending on the linkage mode, there are two types: one is non-reducing sugars formed by dehydration of the hemiacetal (hemiketal) hydroxyl groups of two sugars to form a glycosyl glycoside; the other is reducing sugars formed by glycosidation of the hemiacetal (hemiketal) hydroxyl group of one sugar with the nonhemiacetal (non-hemiketal) hydroxyl group of another sugar, known as glycosyl sugar. The glycosidic bond can be an a-1,4 glycosidic bond, a-1,6 glycosidic bond, P-1,4 glycosidic bond, a-1-2P glycosidic bond, P-1,6 glycosidic bond, a-1,1 glycosidic bond, P-1,3 glycosidic bond, P-2,1 glycosidic bond. Specific examples of disaccharides include, but are not limited to, maltose, isomaltose, lactose, sucrose, chitobiose, rutinose, trehalose, xylobiose, gentiobiose, etc., wherein the monosaccharide units constituting the disaccharide can be the various monosaccharide derivative forms as described above. As used herein, the term "oligosaccharide" refers to low-polymerization sugars composed of 3~9 monosaccharides linked via glycosidic bonds and derivatives thereof, wherein the monosaccharides, glycosidic bonds, and derivatives are as defined above, e.g., but not limited to, mannotriose, selaginotriose, gentianose, plantose, stachyose, raffinose tetrasaccharide, etc. As used herein, the term "polysaccharide" refers to a polymer composed of 10 or more monosaccharide units linked via glycosidic bonds. The glycosidic bonds can be a-type, P-type, or a / p mixed. Structurally, they can be linear, branched, or cyclic. Polysaccharides can be homopolysaccharides composed of one type of monosaccharide, wherein the sugar units of said homopolysaccharides are selected from trioses, tetroses, pentoses, hexoses, heptoses, octoses, or deoxy sugar units, such as dextran, xylan, polysialic acid, etc.; or heteropolysaccharides composed of two or more types of monosaccharides, such as hyaluronic acid, heparin, etc. Examples of polysaccharides include, but are not limited to, dextran, levan, hyaluronic acid, cyclodextrins (a, P, Y, etc.), hydroxyethyl starch, xylan, water-soluble starch, water-soluble cellulose, carboxymethyl cellulose, galactosamine, polysialic acid, rhamnan, Ganoderma lucidum polysaccharide, lentinan, chitin, deacetylated chitosan, alginate, carrageenan, gellan gum, pullulan, scleroglucan, xanthan gum, xyloglucan, amylose, etc. Said polysaccharides can inherently bear or be structurally modified to bear one or more substituents selected from, for example, carboxylic acid group, carboxylate group, amino group, sulfonic acid group, sulfonate group, phosphoric acid group, phosphate group, hydroxyethyl group, hydroxypropyl group, methyl group, acyl group, carboxymethyl group, natural amino acid group, unnatural amino acid group, etc. When describing sugar units, the term "derivative" as used herein primarily refers to phosphate esters of sugars (sugar compounds formed by esterification of one or more hydroxyl groups of a sugar with phosphoric acid), sugar alcohols (sugar compounds formed by reduction of the carbonyl group of a sugar to OH), sugar acids (aldonic acids formed by oxidation of the aldehyde group of an aldose to a carboxyl group, uronic acids formed by oxidation of the primary alcohol group of an aldose to a carboxyl group, and aldaric acids formed by oxidation of both the aldehyde and primary alcohol groups of an aldose to carboxyl groups), deoxy sugars (sugars where one or two hydroxyl groups in the sugar molecule are replaced by hydrogen atoms), amino sugars (sugar derivatives where one or more hydroxyl groups of a sugar are replaced by amino groups), acylated amino sugars (sugar derivatives where the amino group of an amino sugar is acylated), and glycoside forms (sugar-containing derivatives formed by condensation of the hemiacetal hydroxyl group of a sugar with the hydroxyl, amine, or thiol group of another molecule such as an alcohol, sugar, purine, or pyrimidine, i.e., a derivative composed of a sugar residue (sugar lacking the hemiacetal hydroxyl group) and an aglycone linked via a glycosidic bond). Preferred are sugar acids, amino sugars, or acylated amino sugars. Sugar derivatives suitable for the ADCs of the present disclosure can also be derivatives formed by derivatizing a sugar molecule in more than one of the above ways, for example, acylated amino uronic acids, such as 2-acetamido-2-deoxy-D-galacturonic acid, 2-acetamido-2-deoxy-D-glucuronic acid, 2-acetamido-2-deoxy-D-mannuronic acid. As used herein, a specific example of the "property-modulating unit" also includes a "PEG unit". The term "PEG unit" refers to an organic moiety containing repeating ethyleneoxy subunits (PEG or PEG subunits), which can be polydisperse, monodisperse, or discrete (i.e., having a discrete number of ethylene-oxy subunits). Polydisperse PEG is a non-uniform mixture of sizes and molecular weights, whereas monodisperse PEG is typically purified from the non-uniform mixture and thus has a single chain length and molecular weight. Preferred PEG units comprise discrete PEG, which are compounds synthesized in a stepwise manner rather than via a polymerization process. Discrete PEG provides a single molecule with a defined and specified chain length. The PEG unit provided herein includes one or more polyethylene glycol chains, each polyethylene glycol chain consisting of one or more ethyleneoxy subunits covalently linked to each other. Polyethylene glycol chains can be linked together, for example, in a linear, branched, or star configuration. Typically, prior to incorporation into the ADC conjugate, at least one polyethylene glycol chain is derivatized at one end with an alkyl moiety substituted by an electrophilic group to covalently attach to the carbamate nitrogen of a methylene carbamate unit. Typically, the terminal ethyleneoxy group in each polyethylene glycol chain not involved in covalent attachment to the remainder of the linker unit is modified with a PEG capping unit, typically an optionally substituted alkyl group such as -CH3, CH2CH3, or CH2CH2CO2H. Preferred PEG units have a single polyethylene glycol chain with 2 to 24 -CH2CH2O- subunits covalently linked in series. As used herein, a specific example of the "property-modulating unit" also includes a "hydrophilic peptide". The term "hydrophilic peptide" can be attached, for example, to the self-immolative linker of the linker unit, or to the antibody linker. It can be attached directly to the linker unit or via a suitable structural fragment (such as the moiety of formula (A) or (A1) as defined herein). Specifically, a "hydrophilic peptide" refers to an organic moiety comprising repeating subunits -CO-CR'R"-NR-, where one or more amino acids, which may be the same or different from each other, are linked via amide bonds in a linear, branched, or star configuration. Each hydrophilic peptide generally comprises 1-20 amino acids, preferably 4-14 amino acids, more preferably 6-12 amino acids. As used herein, the amino acid monomers constituting the hydrophilic peptide can be natural amino acids, such as alanine (Ala), arginine (Arg), aspartic acid (Asp), asparagine (Asn), histidine (His), glycine (Gly), glutamic acid (Glu), glutamine (Gln), phenylalanine (Phe), lysine (Lys), leucine (Leu), serine (Ser), tyrosine (Tyr), threonine (Thr), isoleucine (Ile), proline (Pro), tryptophan (Trp), valine (Val), cysteine (Cys), methionine (Met). Correspondingly, in the repeating subunit -CO-CR'R"-NR-, R is H and one of R' and R" is H and the other corresponds to the respective group or moiety in the respective natural amino acid; preferred are polar natural amino acids, such as arginine, serine, threonine, tyrosine, cysteine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, histidine, glycine, tryptophan. As used herein, the amino acid monomers constituting the hydrophilic peptide can also be amino acids other than the twenty natural amino acids mentioned above, such as ornithine (Orn), P-alanine (P-Ala), citrulline (Cit), sarcosine (Sar), and those amino acids where R, R', R" in the repeating subunit -CO-CR'R"-NR- differ from the corresponding groups or fragments in natural amino acids. For example, R, R', R" are selected from alkyl, aryl, acyl, amido, ketone, azido, hydroxyl, mercapto, hydrazine, cyano, quaternary ammonium, halogen, hydrazide, alkenyl, alkynyl, ether, thiol, seleno, sulfonic acid, sulfate, borate, phosphono, phosphate, heterocycle, enone, imine, aldehyde, ester, thioacid, hydroxylamine, amino, etc., or any combination thereof, or groups containing alkyl, aryl, acyl, amido, ketone, azido, hydroxyl, mercapto, hydrazine, cyano, quaternary ammonium, halogen, hydrazide, alkenyl, alkynyl, ether, thiol, seleno, sulfonic acid, sulfate, borate, phosphono, phosphate, heterocycle, enone, imine, aldehyde, ester, thioacid, hydroxylamine, amino, etc. Preferred are those amino acids where R, R', and / or R" contain hydrophilic groups, such as R, R', R" each independently is carboxyl, sulfonic acid, sulfate, phosphate, amino, amido, quaternary ammonium, oxygencontaining group, ether group, mercapto, or hydroxyl, or is a group containing carboxyl, sulfonic acid, sulfate, phosphate, amino, amido, quaternary ammonium, oxygen-containing group, ether group, mercapto, and / or hydroxyl, such as alkyl, e.g., C1-6 alkyl. For the ADCs of the present disclosure, when the linker unit carries a hydrophilic peptide, at least 50% to 100% of the amino acids constituting the hydrophilic peptide are hydrophilic amino acids, e.g., 80%-100%, such as 60%, 70%, 80%, 90%, or 100%. Said amino acids are preferably arginine, serine, threonine, tyrosine, cysteine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, histidine, glycine, tryptophan, ornithine, citrulline (Cit), sarcosine (Sar). For the ADCs of the present disclosure, the hydrophilic peptide carried by the linker unit is preferably 4-14 units of polysarcosine, polyarginine, or polyglycine, more preferably 6-12 units of polysarcosine. As used herein, the term "drug:antibody ratio" or "DAR" refers to the ratio of the number of drug moieties (D) conjugated to the Ab moiety described herein relative to the Ab moiety in the ADC conjugate. In some embodiments described herein, DAR can be determined by q in formula I, for example, DAR can be an integer or non-integer of at least 1, such as about 1 to 20, e.g., about 2-18, 4-16, 5-12, 6-10, 1-10, 1-8, 2-8, 3-8, 2-6, 4-6, 4-8, 6-8, 6-10, e.g., about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15. DAR can also be calculated as the average DAR of the product population, i.e., the overall ratio of small molecule drug moieties (D) conjugated to the Ab moiety described herein in the product as measured by detection methods (e.g., by conventional methods such as mass spectrometry, ELISA assay, electrophoresis, and / or HPLC). This DAR is referred to herein as the average DAR. In some embodiments, the average DAR value of the conjugates of the present disclosure is about 1 to 20, e.g., about 2-18, 4-16, 5-12, 1-10, 1-8, 6-10, 2-8, 3-8, 2-6, 4-6, 4-8, 6-8, 6-10, e.g., 1.0-8.0, 2.06.0, e.g., about 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8.0, 7.9, 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, or 10.0, or a range having two of these values as endpoints. As used herein, the term "halogen" generally refers to fluorine, chlorine, bromine, iodine, for example, fluorine, chlorine. As used herein, the term "alkyl" refers to a straight or branched chain aliphatic saturated hydrocarbon group having the specified number of carbon atoms. Specifically, alkyl can have 1 to 14, 1 to 12, 1 to 10, 1 to 8, 1 to 7, 1 to 6, 1 to 5, 1 to 4, 1 to 3, or 1 to 2 carbon atoms. Examples of suitable C1-14 alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, isohexyl, dimethylmethyl, dipropylmethyl, ethylbutylmethyl, diethylmethyl, methylethylmethyl, ethylpropylmethyl, diethylethyl, diethylpropyl, dipropylethyl, etc. Particular alkyl groups have 1 to 7 carbon atoms, e.g., 1 to 6 carbon atoms, 1 to 4 carbon atoms. As used herein, the term "-O-alkyl" or "alkoxy" means an alkyl group as defined herein attached to the remainder of the molecule through an oxygen atom. Specifically, -O-alkyl has 1-10, e.g., 1 to 8, 1 to 6, 1 to 5, 1 to 4, 1 to 3, or 1 to 2 carbon atoms. For example, as used herein, the term "-O- C1-6 alkyl" refers to a straight or branched chain saturated hydrocarbon group having 1 to 6 carbon atoms attached to the remainder of the molecule through an oxygen atom. Examples thereof include, e.g., -O-methyl, -O-ethyl, -O-propyl (including -O-n-propyl and -O-isopropyl), -O-butyl (including -O-n-butyl, -O-isobutyl, -O-sec-butyl, or -O-tert-butyl), -O-pentyl (including -O-n-pentyl, -O-isopentyl, -O-neopentyl), -O-n-hexyl, 2-methylpentyl-O-, etc. As used herein, the term " C1-6 alkyl optionally substituted by halogen" refers to the abovementioned C1-6 alkyl group, wherein one or more (e.g., 1, 2, 3, 4, or 5) hydrogen atoms are optionally replaced by halogen. Those skilled in the art will understand that when more than one halogen substituent is present, the halogens can be the same or different and can be located on the same or different carbon atoms. Examples of "halogen-substituted C1-6 alkyl" include, e.g., -CH2F, -CHF2, -CF3, -CCI3, -C2F5, -C2CI5, -CH2CF3, -CH2CI, -CH2CH2CF3, or -CF(CF3)2, etc. As used herein, the term "alkenyl" refers to a straight or branched chain unsaturated hydrocarbon group consisting of carbon and hydrogen atoms and containing at least one double bond. Specifically, alkenyl has 2-8, e.g., 2 to 6, 2 to 5, 2 to 4, or 2 to 3 carbon atoms. For example, as used herein, the term " C2-C6 alkenyl" refers to an alkenyl group having 2 to 6 carbon atoms, such as ethenyl, propenyl, allyl, 1-butenyl, 2-butenyl, 1,3-butadienyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 1,3-pentadienyl, 1,4-pentadienyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 1,4-hexadienyl, etc. The carbon atom of the alkenyl group attached to the remainder of the molecule can be saturated or can be an olefinic carbon atom. As used herein, the term "alkynyl" refers to a straight or branched chain unsaturated hydrocarbon group consisting of carbon and hydrogen atoms and containing at least one triple bond. Specifically, alkynyl has 2-8, e.g., 2 to 6, 2 to 5, 2 to 4, or 2 to 3 carbon atoms. For example, as used herein, the term "C2-6 alkynyl" refers to an alkynyl group having 2 to 6 carbon atoms, such as ethynyl, propynyl, propargyl, 1-butynyl, 2-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-methyl-1-pentynyl, 1-hexynyl, 2-hexynyl, 3-hexynyl, 5-methyl-2-hexynyl, etc. The carbon atom of the alkynyl group attached to the remainder of the molecule can be saturated or can be an acetylenic carbon atom. As used herein, the term "alkylene" refers to a divalent group obtained by removing two hydrogen atoms from the same or two different carbon atoms of a straight or branched chain saturated alkane. Specifically, alkylene has 1-10 carbon atoms, e.g., 1 to 6, 1 to 5, 1 to 4, 1 to 3, or 1 to 2 carbon atoms. For example, as used herein, the term " C1-6 alkylene" refers to a straight or branched chain alkylene group having 1 to 6 carbon atoms, including but not limited to methylene, ethylene, propylene, butylene, etc. As used herein, a specific type of "alkylene" refers to a divalent group obtained by removing two hydrogen atoms from the same carbon atom of a straight or branched chain saturated alkane, such as the =C(Rd)2 group defined in the drug P part of the present disclosure, as shown in the structural N fragment         ।    . As used herein, the term "alkenylene" refers to a divalent group obtained by removing two hydrogen atoms from the same or two different carbon atoms of a straight or branched chain unsaturated alkene containing at least one double bond. Specifically, alkenylene has 2-8, e.g., 2 to 6, 2 to 5, 2 to 4, or 2 to 3 carbon atoms. For example, as used herein, the term "C2-6 alkenylene" refers to a straight or branched chain alkenylene group having 2 to 6 carbon atoms, such as ethenylidene, propenylene, allylene, butenylene, pentenylene, and hexenylene. As used herein, the term "alkynylene" refers to a divalent group obtained by removing two hydrogen atoms from the same or two different carbon atoms of a straight or branched chain unsaturated alkyne containing at least one triple bond. Specifically, alkynylene has 2-8, e.g., 2 to 6, 2 to 5, 2 to 4, or 2 to 3 carbon atoms. For example, as used herein, the term "C2-C6 alkynylene" refers to a straight or branched chain alkynylene group having 2 to 6 carbon atoms, such as ethynylene, propynylene, propargylene, butynylene, pentynylene, and hexynylene. As used herein, the term "cycloalkyl" refers to a monocyclic, fused polycyclic, bridged polycyclic, or spirocyclic non-aromatic monovalent hydrocarbon ring structure having the specified number of ring atoms, which can be saturated or unsaturated, e.g., containing one or more double bonds. Cycloalkyl groups can contain 3 or more carbon atoms in the ring, e.g., 3-18, 3-10, or 3-8 carbon atoms, such as C3-10 cycloalkyl, C3-8 cycloalkyl, C3-6 cycloalkyl, C5-6 cycloalkyl. Examples of cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl. As used herein, the term "heterocycle" or "heterocyclyl" refers to a 5-20 membered (e.g., 5-14 membered, 5-8 membered, 5-6 membered) aromatic or non-aromatic monocyclic, bicyclic, or polycyclic ring system having 1-4 ring heteroatoms independently selected from N, O, or S. One or more N, C, or S atoms in the heterocycle can be oxidized. Preferably, the heterocycle is a 5-10 membered ring system, monocyclic or fused bicyclic. Representative examples include, but are not limited to, pyrrolidine, azetidine, piperidine, morpholine, tetrahydrofuran, tetrahydropyran, benzofuran, benzothiophene, indole, benzopyrazole, pyrrole, thiophene, furan, thiazole, imidazole, pyrazole, pyrimidine, pyridine, pyrazine, pyridazine, isothiazole, and isoxazole. As used herein, the term "heterocycloalkyl" means a monocyclic, fused polycyclic, spirocyclic, or bridged polycyclic non-aromatic saturated ring structure including one or more (e.g., 1, 2, 3, or 4) heteroatoms independently selected from O, N, and S, having the specified number of ring atoms, or an N-oxide thereof, or an S-oxide or S-dioxide thereof. Heterocycloalkyl can have 3 to 12 ring members (can be referred to as 3-12 membered heterocycloalkyl), e.g., 3 to 10 ring members, 3 to 8 ring members, 3 to 7 ring members, 4 to 7 ring members, 4 to 6 ring members, 5 to 6 ring members. Heterocycloalkyl typically contains up to 4 (e.g., 1, 2, 3, or 4) heteroatoms, e.g., a 4-7 membered heterocycloalkyl containing 1 to 3 heteroatoms selected from N, O, S. Examples of suitable heterocycloalkyl groups include, but are not limited to, azetidinyl, oxetanyl, thietanyl, pyrrolidinyl (e.g., 1-pyrrolidinyl, 2-pyrrolidinyl, and 3-pyrrolidinyl), tetrahydrofuranyl (e.g., 1-tetrahydrofuranyl, 2-tetrahydrofuranyl, and 3-tetrahydrofuranyl), tetrahydrothienyl (e.g., 1-tetrahydrothienyl, 2-tetrahydrothienyl, and 3-tetrahydrothienyl), piperidinyl (e.g., 1-piperidinyl, 2-piperidinyl, 3-piperidinyl, and 4-piperidinyl), tetrahydropyranyl (e.g., 4-tetrahydropyranyl), tetrahydrothiopyranyl (e.g., 4-tetrahydrothiopyranyl), morpholinyl (e.g., morpholino), thiomorpholinyl, dioxanyl, piperazinyl, or azepanyl, diazepanyl such as 1,4-diazepanyl, 3,6-diaza-bicyclo[3.1.1]heptyl, or 3-aza-bicyclo[3.2.1]octyl. The atom of the heterocycloalkyl group attached to the remainder of the compound can be a carbon atom or a heteroatom, as long as it is chemically feasible. As used herein, the term "aryl" refers to a monocyclic or polycyclic aromatic hydrocarbon group having 6-20, e.g., 6-12, carbon atoms in the ring portion. Preferably, aryl is (C6—Cio)aryl. Non-limiting examples include phenyl, biphenyl, naphthyl, or tetrahydronaphthyl, each of which can be optionally substituted by 1-4 substituents such as alkyl, trifluoromethyl, cycloalkyl, halogen, hydroxy, alkoxy, acyl, alkyl-C(O)-O-, aryl-O-, heteroaryl-O-, amino, mercapto, alkyl-S-, aryl-S-, nitro, cyano, carboxy, alkyl-O-C(O)-, carbamoyl, alkyl-S(O)-, sulfonyl, sulfonylamino, heterocyclyl, etc. As used herein, the term "heteroaryl" refers to a 5-20 membered (e.g., 5-14 membered, 5-8 membered, 5-6 membered) aromatic monocyclic or polycyclic ring system containing 1-4 heteroatoms selected from N, O, or S, which can be substituted or unsubstituted. Preferably, heteroaryl is a 5-10 membered ring system, monocyclic or fused bicyclic. Representative heteroaryl groups include 2- or 3-thienyl, 2- or 3-furyl, 2- or 3-pyrrolyl, 2-, 4- or 5-imidazolyl, 3-, 4- or 5-pyrazolyl, 2-, 4- or 5-thiazolyl, 3-, 4- or 5-isothiazolyl, 2-, 4- or 5-oxazolyl, 3-, 4- or 5-isoxazolyl, 3-or 5-1,2,4-triazolyl, 4- or 5-1,2,3-triazolyl, tetrazolyl, 2-, 3- or 4-pyridyl, 3- or 4-pyridazinyl, 3-, 4-or 5-pyrazinyl, 2-pyrazinyl, 2-, 4- or 5-pyrimidinyl. As used herein, the term "heteroalkyl" refers to a stable straight or branched chain hydrocarbon that is fully saturated or contains 1 to 3 degrees of unsaturation, consisting of the indicated number of carbon atoms and one to ten, preferably one to three, heteroatoms selected from O, N, Si, and S, wherein the nitrogen and sulfur atoms can be optionally oxidized and the nitrogen heteroatom can be optionally quaternized. The heteroatoms O, N, Si, and S can be placed at any internal position of the heteroalkyl group or at the position where the heteroalkyl group is attached to the remainder of the molecule. Representative examples of heteroalkyl include -CH2-CH2-O-CH3, -CH2-CH2-NH-CH3, -CH2-CH2-N(CH3)-CH3, -CH2-S-CH2-CH3, --CH2-CH2-S(O)-CH3, --NH-CH2-CH2-NH-C(O)-CH2-CH3, -CH2-CH2-S(O)2-CH3, -CH=CH-O-CH3, -Si(CH3)3, -CH2-CH=N-O-CH3, and -CH=CH- N(CH3)-CH3. Up to two heteroatoms can be consecutive, such as -CH2-NH-OCH3 and -CH2-O-Si(CH3)3. Typically, C1 to C4 heteroalkyl or heteroalkylene has 1 to 4 carbon atoms and 1 or 2 heteroatoms, C1 to C3 heteroalkyl or heteroalkylene has 1 to 3 carbon atoms and 1 or 2 heteroatoms. In some aspects, heteroalkyl and heteroalkylene are saturated. Unless otherwise indicated, the term "substituted" when used to define various groups means that the corresponding group can be substituted by, for example but not limited to, the following groups as defined herein or conventional in the art: alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, halogen, cyano, nitro, azido, carboxy, hydroxy, mercapto, amino, mono- or di-alkylamino, mono- or di-cycloalkylamino, mono- or di-arylamino, mono- or di-heterocyclylamino, mono- or di-heteroarylamino, alkyl- or cycloalkyl- or heterocyclyl- or heteroaryl- or aryl-oxy, alkyl-or cycloalkyl- or heterocyclyl- or heteroaryl- or aryl-thio, alkyl- or cycloalkyl- or heterocyclyl- or heteroaryl- or aryl-acyl, alkyl- or cycloalkyl- or heterocyclyl- or heteroaryl- or aryl-acylamino, alkyl-or cycloalkyl- or heterocyclyl- or heteroaryl- or aryl-acyloxy, alkyl- or cycloalkyl- or heterocyclyl-or heteroaryl- or aryl-sulfonyl, alkyl- or cycloalkyl- or heterocyclyl- or heteroaryl- or arylsulfonyloxy, alkyl- or cycloalkyl- or heterocyclyl- or heteroaryl- or aryl-sulfonylamino, or the above optionally substituted amino-carbamoyl, and groups thereof further substituted by the remaining optional substituents, wherein the various groups are as defined herein. Examples of substituents include, but are not limited to, one or more groups independently selected from: halogen, OH, SH, CN, NH2, NHCH3, N(CH3)2, NO2, N3, C(O)CH3, COOH, C(O)-amino, OCOCH3, methyl, ethyl, propyl, iso-propyl, butyl, isobutyl, sec-butyl, tert-butyl, cyclopropyl, methoxy, ethoxy, propoxy, oxo, trifluoromethyl, difluoromethyl, sulfonylamino, methylsulfonylamino, SO, SO2, phenyl, piperidinyl, piperazinyl, and pyrimidinyl. As used herein, the term "substitution" or "substituted" means that one or more (e.g., 1, 2, 3, or 4) hydrogens on the designated atom are replaced with the designated groups, provided that the normal valence of the designated atom is not exceeded under the current circumstances and a stable compound is formed. Combinations of substituents and variables are permissible only if such combinations result in stable compounds. The term "optionally substituted" as used herein, unless otherwise indicated, means that a group can be unsubstituted or substituted by one or more (e.g., 1,2, 3, 4, or 5 or more, or any range derivable therein) of the substituents listed for that group, wherein the substituents can be the same or different. In one embodiment, an optionally substituted group has 1 substituent. In another embodiment, an optionally substituted group has 2 identical or different substituents. In another embodiment, an optionally substituted group has 3 identical or different substituents. In another embodiment, an optionally substituted group has 4 identical or different substituents. In another embodiment, an optionally substituted group has 5 identical or different substituents. Many of the groups defined herein are optionally substituted, and the lists of substituents provided in the specific group definitions are not intended to limit the substituents defined elsewhere in the specification and claims. As used herein, the term "pharmaceutically acceptable salt" represents a salt that retains the biological effectiveness and properties of the ADC conjugate of the present disclosure and is not biologically or otherwise undesirable. The ADC conjugates of the present disclosure can exist in the form of their pharmaceutically acceptable salts, including acid addition salts and base addition salts. In the present disclosure, pharmaceutically acceptable non-toxic acid addition salts represent salts formed by the ADC conjugates of the present disclosure with organic or inorganic acids, including but not limited to hydrochloric acid, sulfuric acid, hydrobromic acid, hydroiodic acid, phosphoric acid, nitric acid, perchloric acid, acetic acid, oxalic acid, maleic acid, fumaric acid, tartaric acid, benzenesulfonic acid, methanesulfonic acid, salicylic acid, succinic acid, citric acid, lactic acid, propionic acid, benzoic acid, p-toluenesulfonic acid, malic acid, etc. Pharmaceutically acceptable non-toxic base addition salts represent salts formed by the ADC conjugates of the present disclosure with organic or inorganic bases, including but not limited to alkali metal salts, e.g., lithium, sodium, or potassium salts; alkaline earth metal salts, e.g., calcium or magnesium salts; organic base salts, e.g., ammonium salts formed with organic bases containing N groups. As used herein, the term "solvate" represents an association formed by one or more solvent molecules with the ADC conjugate of the present disclosure. Solvents forming solvates include, but are not limited to, water, methanol, ethanol, isopropanol, ethyl acetate, tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, etc. It should be understood that such solvates of the compounds of the present invention also include solvates of the pharmaceutically acceptable salts of the compounds of the present invention. As used herein, the term "isotopic variant" refers to a compound in which one or more atoms constituting the compound are replaced with atoms having an atomic mass or mass number different from that normally found in nature. Examples of isotopes that can be incorporated into one or more atoms of the compounds of the present disclosure include, for example, 2H, 3H, 13C, 14C, 15N, 17O, 18O, 31P, 32P, 35S, and 18F, thereby forming isotopic variants of the compounds of the present disclosure, whether or not they are radioactive, and are intended to be encompassed within the scope of the present disclosure. In certain embodiments, the compounds of the present disclosure are provided in unlabeled form, while in other embodiments, they are provided in isotopically labeled form, such as the hydrogen isotope D-labeled form. In particular, one or more H atoms in the R9, R10, and R11 groups defined in the drug P part herein can be replaced with the isotope D, for example, R9 and R10 can each independently be H or D, and R11 can be substituted by one or more D atoms, particularly a -C1-6 alkyl substituted by one or more D atoms. As used herein, the term "isomer" refers to any stereoisomer, enantiomeric mixture, including racemates, diastereomeric mixtures, geometric isomers, atropisomers, and / or tautomers that may exist structurally for a compound. The methods for determining and separating the stereochemistry of such isomers are well known to those skilled in the art (S. P. Parker, Ed., McGraw-Hill Dictionary of Chemical Terms (1984) McGraw-Hill Book Company, New York; and Eliel, E. and Wilen, S., "Stereochemistry of Organic Compounds", John Wiley & Sons, Inc., New York, 1994). The present disclosure encompasses all possible isomeric forms of the compounds defined herein, and their pharmaceutically acceptable salts or solvates, unless otherwise indicated. Furthermore, the compounds of the present disclosure can exist as mixtures of two or more different structures in rapid equilibrium (commonly referred to as tautomers). It is to be understood that the scope of the present application covers all such isomers or mixtures thereof in any ratio (e.g., 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%). Certain compounds of the present disclosure contain at least one (e.g., 1, 2, 3, or 4) asymmetric center, and therefore can be prepared as (R)- or (S)-stereoisomers or as mixtures thereof. The use of "    " or "    " in the structural formulas or structural fragments of the compounds of the present disclosure indicates the configuration of the stereocenter, i.e., the chiral center. Correspondingly, in the naming of the compounds or intermediates provided by the present invention, the configuration with respect to that chiral center is represented by R or S; "    " attached to a chiral center indicates the racemic form in which both configurations at that chiral center are present simultaneously, such as        I representing a mixture of         I and        I . In some definitions of the compounds of the present disclosure, axial chirality can also be used to represent the configuration of the compound. The determination of these configurations uses the Cahn-Ingold-Prelog rules well known to those skilled in the art. The absolute configuration of axial chirality in the two exemplary structures below is described as follows: Isomer 1, the axis chiral configuration is labeled as Ra Isomer 2, the axis chiral configuration is labeled as Sa When the bond linking the axially chiral center is marked with "*", it indicates that the compound is of a single chiral configuration obtained by SFC resolution, but the absolute configuration is uncertain. For example, means It should be understood that when a person skilled in the art can determine, based on the compound structures shown herein, that a compound exists as a pair of chiral isomers and that the isomers can be readily resolved based on conventional methods in the art, then the disclosure of the racemate of that compound herein (whether by structural formula or chemical name) should be deemed to have separately disclosed each individual isomer of that compound. As used herein, in the definitions, structural formulas, or structural fragments of compounds, the number of groups attached to each atom depends on the chemical valence of that atom and need not be fully shown. Generally speaking, only non-hydrogen groups are shown in the group definitions, structural formulas, or structural fragments; unshown groups generally represent H. A person skilled in the art can readily determine whether unshown groups are present and their number. The "      " used in the structural fragments involved herein indicates that the bond crossing it is the bond connecting that structural fragment to the remainder of the molecule. Substituents shown across chemical bonds in cyclic structural fragments involved herein, such (Rl2)m as -(Ri2)m in , indicate that the m of R12 substituents can be substituted at any chemically feasible substitution site(s) on the ring, including X when chemically feasible. Unless otherwise specified, Cn-n+m Or Cn—Cm in the definitions of the compounds of the present invention includes various cases of n to n+m carbons, for example, C1-6 includes Ci, C2, C3, C4, C5, and C6, and also includes any range within n to n+m, for example, C0-6 includes Ci, C2, C3, C4, C5, C6, C0-1, C0-2, C0-3, Co-4, C0-5, C1-2, C1-3, Ci-4, C2-3, etc.; C1-6 includes C1-2, C1-3, Ci-4, C2-6, C3-6, etc. As used herein, the term "about" used to modify a numerical value, numerical range, or parameter means that the value or parameter associated with it fluctuates by ±10%, such as ±5%, ±2%, or ±1%. By way of example, the expression "about 100" as used herein includes 90 and 110 and all values in between (e.g., 90.5, 95, 101, 105, 109.95, etc.). For ratios, the term "about" is used to modify each number of the given ratio, for example, a ratio of "about 1:1" means the ratio is (0.9-1.1):(0.9-1.1); and a range of "about n-m" or "about n to about m" means a range from 90% n-110% n to 90% m-110% m. As used herein, "pharmaceutically acceptable" and "pharmaceutical" are used interchangeably as the context allows and without contradiction. As used herein, the term "pharmaceutical composition" refers to a composition that is in a form effective for the biological activity of the active ingredients contained therein and contains no additional ingredients that are unacceptably toxic to a subject to whom the composition is administered. As used herein, the terms "pharmaceutically acceptable excipient", "pharmaceutically acceptable carrier", and "therapeutically inert excipient" are used interchangeably and represent any pharmaceutically acceptable ingredient in a pharmaceutical composition that has no therapeutic activity and is non-toxic to the subject administered, such as disintegrants, binders, fillers, solvents, buffers, tonicity agents, stabilizers, antioxidants, surfactants, carriers, diluents, or lubricants used to formulate pharmaceutical products. As used herein, the term "pharmaceutical combination" refers to a non-fixed combination product or a fixed combination product, including but not limited to kits, pharmaceutical compositions. The term "non-fixed combination" means that the active ingredients, e.g., (i) the ADC conjugate of the present disclosure and (ii) the other therapeutic agent, are administered to a patient as separate entities simultaneously, without specific time limits, or sequentially at the same or different time intervals, wherein such administration provides the patient with prophylactically or therapeutically effective levels of the two or more active agents. In some embodiments, the ADC conjugate of the present disclosure and the other therapeutic agent used in the pharmaceutical combination are administered at levels not exceeding those at which they are used alone. The term "fixed combination" means that two or more active agents are administered to a patient simultaneously as a single entity. The doses and / or time intervals for the two or more active agents are preferably selected so that their combined use produces an effect greater than that achievable with either component alone in treating a disease or condition. Each component can be in separate formulation forms, which can be the same or different. As used herein, the term "combination therapy" refers to the administration of two or more therapeutic agents or treatment modalities, such as radiation therapy or surgery, to treat a disease described herein. Such administration includes co-administering these therapeutic agents in a substantially simultaneous manner, e.g., in a single capsule with a fixed ratio of active ingredients. Alternatively, such administration includes co-administration of each active ingredient in multiple or separate containers (e.g., tablets, capsules, powders, and liquids). Powders and / or liquids can be reconstituted or diluted to the desired dose prior to administration. Furthermore, such administration also includes sequential use of each type of therapeutic agent at substantially the same time or at different times. In either case, the treatment regimen will provide a beneficial effect of the drug combination in treating the condition or disease described herein. As used herein, the terms "individual" or "subject" are used interchangeably and refer to a mammal. Mammals include, but are not limited to, domesticated animals (e.g., cows, sheep, cats, dogs, and horses), primates (e.g., humans and non-human primates such as monkeys), rabbits, and rodents (e.g., mice and rats). In particular, the subject is a human. As used herein, the term "treatment" refers to slowing, interrupting, arresting, alleviating, stopping, reducing, or reversing the progression or severity of an existing symptom, disorder, condition, or disease. As used herein, the term "prevention" includes inhibition of the occurrence or development of a disease or condition or a symptom of a particular disease or condition. In some embodiments, a subject with a family history of cancer is a candidate for a prophylactic regimen. Generally, in the context of cancer, the term "prevention" refers to drug administration before the onset of signs or symptoms of cancer, particularly in subjects at risk for cancer. As used herein, the term "effective amount" refers to such an amount or dose of the antibodydrug conjugate or composition or combination of the present disclosure that, when administered to a patient in a single or multiple doses, produces the desired effect in the patient in need of treatment or prevention. As used herein, the term "therapeutically effective amount" refers to an amount effective to achieve the desired therapeutic result at the required doses and for the required period of time. A therapeutically effective amount is also one in which any toxic or harmful effects of the antibodydrug conjugate or composition or combination of the present disclosure are outweighed by the therapeutic benefits. Relative to an untreated individual, a "therapeutically effective amount" preferably achieves at least about 30%, even more preferably at least about 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or even 100% inhibition of a measurable parameter (e.g., tumor volume). As used herein, the term "prophylactically effective amount" refers to an amount effective to achieve the desired prophylactic result at the required doses and for the required period of time. Typically, since a prophylactic dose is used in a subject prior to or at an earlier stage of the disease, the prophylactically effective amount will be less than the therapeutically effective amount. As used in this specification and the appended claims, the term "comprise" and variations thereof such as "comprising" and "includes" mean "including but not limited to" and are not intended to exclude, for example, other additives, components, integers, or steps. When an element is described as comprising multiple components, steps, or conditions, it is to be understood that the element can also be described as comprising any combination of the multiple components, steps, or conditions, or as "consisting of"' or "consisting essentially of"' the multiple or combined components, steps, or conditions. I: Antibody-Drug Conjugate In one aspect, the present disclosure provides an antibody-drug conjugate (ADC) of formula (X) or a pharmaceutically acceptable salt or solvate thereof: [P-L]q-Ab                  (X) wherein, P represents a Ras inhibitor, e.g., a KRas inhibitor; L represents a linker unit connecting P to Ab; q represents the number of [P-L] units connected to Ab, which is an integer or non-integer of at least 1, e.g., q = 1 to 20, such as about 1-10, 1-8, 2-8, 3-10, 3-8, 4-10, 4-8, 6-8, or 6-10; Ab represents an antibody or antigen-binding fragment. In some embodiments of formula X, q represents an integer selected from 1 to 20, including 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. In some cases, q ranges from 1 to 2, 1 to 3, 1 to 4, 1 to 5, 1 to 6, 1 to 7, 1 to 8, 1 to 9, 1 to 10, 1 to 11, 1 to 12, 1 to 13, 1 to 14, 1 to 15, 1 to 16, 1 to 17, 1 to 18, 1 to 19, or 1 to 20, or is a range formed by any two values between 1 and 20, e.g., 2 to 10, 2 to 8, 2 to 6, 2 to 4, 3 to 8, 3 to 10, 4 to 6, 4 to 8, 4 to 10, 6 to 8, or 6 to 10. In other embodiments, formula X describes an ADC in an ADC mixture, which exhibits a q value ranging from 1 to 2, 1 to 3, 1 to 4, 1 to 5, 1 to 6, 1 to 7, 1 to 8, 1 to 9, 1 to 10, 1 to 11, 1 to 12, 1 to 13, 1 to 14, 1 to 15, 1 to 16, 1 to 17, 1 to 18, 1 to 19, or 1 to 20, or a range formed by any two values between 1 and 20, e.g., 2 to 10, 2 to 8, 2 to 6, 2 to 4, 3 to 8, 3 to 10, 4 to 6, 4 to 8, 4 to 10, 6 to 8, or 6 to 10. In certain embodiments, formula X describes an ADC in an ADC mixture such that more than 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% of the ADCs in the mixture have a q value of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. In some embodiments, formula X describes an ADC in an ADC mixture such that more than 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% of the ADCs in the mixture have a q value ranging from 1 to 2, 1 to 3, 1 to 4, 1 to 5, 1 to 6, 1 to 7, 1 to 8, 1 to 9, 1 to 10, 1 to 11, 1 to 12, 1 to 13, 1 to 14, 1 to 15, 1 to 16, 1 to 17, 1 to 18, 1 to 19, or 1 to 20, or a range formed by any two values between 1 and 20, e.g., 2 to 10, 2 to 8, 2 to 6, 2 to 4, 3 to 8, 3 to 10, 4 to 6, 4 to 8, 4 to 10, 6 to 8, or 6 to 10. In other embodiments, formula X describes an ADC mixture, in which case q is "qavg", which represents the average of the q values of the mixture, or the average DAR, i.e., the average number of linker units (L) connected to a given antibody (Ab) in the mixture. In such embodiments, qavg or average DAR represents an integer or non-integer value from 1 to 20, e.g., about 1 to 2, 1 to 3, 1 to 4, 1 to 5, 1 to 6, 1 to 7, 1 to 8, 1 to 9, 1 to 10, 1 to 11, 1 to 12, 1 to 13, 1 to 14, 1 to 15, 1 to 16, 1 to 17, 1 to 18, 1 to 19, or 1 to 20, or an integer or decimal within a range formed by any two values between 1 and 20, e.g., about 2 to 10, 2 to 8, 2 to 6, 2 to 4, 3 to 8, 3 to 10, 4 to 6, 4 to 8, 4 to 10, 6 to 8, or 6 to 10. In preferred embodiments, q in formula (X) of the present disclosure is an integer or non-integer from 1 to 10 or a range formed by any two values between 1 and 10, e.g., about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, about 1 to 2, 1 to 3, 1 to 4, 1 to 5, 1 to 6, 1 to 7, 1 to 8, 1 to 9, 1 to 10, 2 to 10, 2 to 8, 2 to 6, 2 to 4, 4 to 6, 3 to 8, 3 to 10, 4 to 8, 4-10, 6 to 8, or 6 to 10. In some embodiments, q represents an average DAR of about 3. In some embodiments, q represents an average DAR of about 6. In some embodiments, q represents an average DAR of about 8. In some embodiments, q represents an average DAR of about 1-10, 1-8, 2-8, 3-10, 3-8, 4-10, 48, 6-8, or 6-10. Those skilled in the art will also understand that the various ADCs described herein can be in the form of salts or solvates, and in some specific embodiments, are pharmaceutically acceptable salts. The various components of the ADC conjugates of the present disclosure and the ADC conjugates of the present disclosure composed thereof are described in detail below. Those skilled in the art will understand that the ADCs disclosed herein are essentially "modular" in nature, as each has the modular components Ab, L, and P described above. Throughout this disclosure, various specific non-limiting examples and illustrations of these modular components are described, and the present disclosure encompasses all specific combinations of all module-specific embodiments as if each specific combination were explicitly described individually. Ab—Antibody or Antigen-Binding Fragment In the ADC of the present disclosure, the antibody is an antibody or antigen-binding fragment that specifically binds to a target antigen. Its function is to target and deliver the KRas mutant inhibitor compound to a specific target cell population. Due to the presence of the targeting component or molecule, the antibody or antigen-binding fragment interacts with the specific target cell population, and subsequently releases the free drug within the target cell (intracellular mode) or in the vicinity of the target cell (extracellular mode). In one set of embodiments, the antibody or antigen-binding fragment is bonded to a linker unit that comprises a releasable peptide component. As noted above, other linking components may also be present in the conjugates described herein to provide additional space between the Ras, e.g., KRas mutant, inhibitor compound and the antibody unit, or to provide increased solubility properties to the composition. In some of these embodiments, the antibody or antigen-binding fragment is bonded to the linker unit via a heteroatom thereof. Heteroatoms that may be present on the antibody or antigenbinding fragment for such bonding include sulfur (in one embodiment, from a thiol group of the targeting ligand), oxygen (in one embodiment, from a carboxyl or hydroxyl group of the targeting ligand), and optionally substituted nitrogen (in one embodiment, from a primary or secondary amine functional group of the targeting ligand, or in another embodiment, from an optionally substituted amide nitrogen). These heteroatoms can be present on the antibody unit in the natural state of the ligand, e.g., in a naturally occurring antibody, or can be introduced into the antibody unit by chemical modification or bioengineering. The conjugation site on the antibody affects properties such as ADC stability, pharmacokinetics, and pharmacodynamics. Excessively high drug loading can sometimes lead to rapid plasma clearance, while ADCs with low DAR (drug-to-antibody ratio) may exhibit weak activity. The drug loading on the antibody can be controlled by selecting the conjugation strategy and the conjugation site on the antibody, while maintaining the structural integrity and homogeneity of the antibody. In some embodiments, the antibody or antigen-binding fragment has a thiol functional group such that it is bonded to the linker unit via the sulfur atom of the thiol functional group. In other embodiments, the thiol group is generated by reducing interchain disulfides of the antibody. Thus, in some embodiments, the linker unit is conjugated to a cysteine residue derived from a reduced interchain disulfide in the antibody. In other embodiments, the thiol group is introduced chemically into the antibody, e.g., by introducing a cysteine residue. Accordingly, in some embodiments, the linker unit is conjugated to the antibody or antigen-binding fragment via a cysteine residue introduced into the antibody or antigen-binding fragment. In other embodiments, the antibody or antigen-binding fragment has one or more lysine residues that can react with an activated ester (including but not limited to N-hydroxysuccinimide, pentafluorophenyl, and p-nitrophenyl ester) in the linker unit, and thereby provide an amide bond consisting of the nitrogen atom from the antibody or antigen-binding fragment and the C=O of the linker unit. In other embodiments, the antibody or antigen-binding fragment has one or more lysine residues that can be chemically modified to introduce one or more thiol groups. In these embodiments, the antibody or antigen-binding fragment is covalently attached to the linker unit via the sulfur atom of the thiol functional group. Reagents that can be used to modify lysine in this way include, but are not limited to, N-succinimidyl-S'-acetylthioacetate (SATA) and 2-iminothiolane hydrochloride (Traut's reagent). In other embodiments, the antibody or antigen-binding fragment has one or more carbohydrate groups that can be modified to provide one or more thiol functional groups. The chemically modified antibody or antigen-binding fragment in the ADC is bonded to the linker unit via the sulfur atom of the thiol functional group. In other embodiments, the antibody or antigen-binding fragment has one or more carbohydrate groups that can be oxidized to provide aldehyde (-CHO) functional groups. In these embodiments, the corresponding aldehyde interacts with a reactive site on the linker unit to form a chemical bond between the linker unit and the antibody unit. In other embodiments, artificial attachment sites are introduced into the antibody to achieve more site-specific conjugation. Other protocols for modifying proteins for attachment to linker units or related substances can be found in Coligan et al., Current Protocols in Protein Science, Vol. 2, John Wiley & Sons (2002), which are incorporated herein by reference. In some embodiments, the antibody or antigen-binding fragment is capable of forming a covalent bond between the linker unit and the antibody or antigen-binding fragment corresponding to the antibody unit by interacting with a reactive functional group on the linker unit. The functional group capable of interacting with the antibody unit will depend on the nature of the antibody or antigenbinding fragment. In some embodiments, the reactive group is maleimide. Covalent attachment of the antibody or antigen-binding fragment to the linker unit is achieved through interaction of a thiol functional group of the antibody or antigen-binding fragment with a maleimide functional group of the linker unit, forming a thio-substituted succinimide. The thiol functional group can be present in the natural state of the antibody or antigen-binding fragment, e.g., in naturally occurring residues, or can be introduced into the antibody or antigen-binding fragment by chemical modification or by bioengineering. The antibody constituting the ADC of the present disclosure can be polyclonal, monoclonal, genetically engineered, and / or otherwise modified, suitable for administration to humans, e.g., humanized antibodies or fully human antibodies. In some embodiments, the Ab unit of the ADC of the present disclosure is a monospecific antibody. In some embodiments, the Ab unit of the ADC of the present disclosure is a multispecific antibody. In some embodiments, upon binding to an antigen receptor expressed on the surface of tumor cells, the Ab unit triggers antigen receptor-mediated endocytosis, thereby effectively delivering the anti-tumor drug of the ADC into the tumor cells. In some embodiments, the Ab unit of the ADC of the present disclosure can be a bispecific antibody, a dual variable domain antibody, a multi-chain or single-chain antibody, a single-domain antibody, a camelized antibody, a scFv-Fc antibody, a surrogate antibody, etc. In some embodiments where the Ab unit is a bispecific antibody, one specificity of the antibody can target a tumor-associated antigen to promote specific binding of the ADC to tumor cells, while the other specificity of the antibody can target a tumor cell surface receptor to further promote internalization and degradation of the ADC. Non-limiting examples of such bispecific target combinations include HER2 and PRLR dual targeting on breast cancer cells. In other embodiments, the two specificities of the antibody can target different tumor-associated antigens, respectively, to provide a mechanism against drug resistance. Non-limiting examples of such bispecific target combinations include EGFR and MET dual targeting on lung cancer cells. In other embodiments, the two specificities of the antibody can also target different epitopes of the same tumor-associated antigen to increase antibody selectivity for cancer cells and / or enhance internalization and transport to lysosomes by inducing clustering and cross-linking of the antigen on the tumor cell surface. Non-limiting examples of such tumor-associated antigens include HER2 on breast cancer cells. The antibody portion constituting the ADC of the present disclosure can be in the form of a fulllength antibody, which can have or be derived from any antibody isotype, including, for example, IgA, IgD, IgE, IgG, IgM, or IgY. In some embodiments, the antibody constituting the ADC is an IgG (e.g., IgG1, IgG2, IgG3, or IgG4). In some embodiments, the antibody constituting the ADC comprises all or part of the constant region of an IgG immunoglobulin. The antibody portion constituting the ADC of the present disclosure can be a functionally active fragment, derivative, or analog of an antibody that immunospecifically binds to a target cell (e.g., cancer cell antigen, viral antigen, or microbial antigen). In this regard, "functionally active" means that the fragment, derivative, or analog is capable of immunospecifically binding to the target cell. Useful antibody fragments include, for example but not limited to, F(ab')2 fragments, Fab fragments, Fvs, single-chain antibodies, diabodies, triabodies, tetrabodies, scFv, scFv-FV, or any other molecule with the same specificity as the antibody. The fragments can be obtained by molecular engineering or by chemical or enzymatic treatment of intact antibodies or antibody chains or by recombinant means. Useful modified antibody analogs and derivatives include, for example but not limited to, derivatives and analogs of antibodies obtained by glycosylation, acetylation, PEGylation, phosphorylation, amidation, derivatization by known protecting / blocking groups, proteolytic cleavage, linking to cellular antibody units or other proteins, etc. Any of a number of chemical modifications can be carried out by known techniques, including but not limited to specific chemical cleavage, acetylation, formylation, metabolic synthesis in the presence of tunicamycin, etc. Target Antigen and Antibody The antibody portion of the ADC of the present disclosure can target any suitable target molecule present on the surface of the target cell, e.g., a polypeptide, protein, polysaccharide, or lipid molecule. The binding of the antibody to the target molecule should be highly specific to ensure that the ADC specifically binds to the target cell, reducing off-target toxicity. In some embodiments, the binding affinity of the antibody to the target molecule can be selected at the nanomolar or sub-nanomolar level. Suitable target antigens can be selected by searching for cell surface proteins that are highly expressed in tumors but low or even nearly absent in non-malignant tissues. In some embodiments, such target molecules are membrane antigens expressed on the surface of target tumor cells, such as tumor-specific antigens or tumor-associated antigens, the tumor includes hematological tumors and solid tumors, including primary and metastatic tumors. In particularly preferred embodiments, the antibody or antigen-binding fragment in the ADC of the present disclosure specifically binds to one or more tumor-specific antigens or tumor-associated antigens, or immune cell-associated antigens. In some embodiments, the tumor-specific antigen or tumor-associated antigen targeted by the antibody portion of the ADC of the present disclosure is selected from: HER2, Her3, HER1 (ErbBl), HER4 (ErbB4), TROP2, Nectin-4, tissue factor, PD-L1, PD-1, PD-L1 / PD-L2, MET, CLDN18.2, KIT, CTLA-4, RPR1, ephrin A2 receptor (EphA2), folate receptor (FRa), mesothelin, endothelin receptor, GCPII, IL-13Ra, BCMA, GD2, CLL-1, CA-IX, MUC1, 5T4, AOC3, ALK, AXL, C242, CA-125, CCL11, CCR5, CD2, CD3, CD4, CDS, CD15, CA15-3, CD16, CD18, CD19, CD20, CD21, CD22, CD25, CD30, CD32, CD33, CD37, CD38, CD44, CD52, CD56, CD64, CD66e, CD70, CD72, CD74, CD79a, CD79b, CD123, CD138, CD142, CD174, CD276, CDH3, CCD79b, CLDN9 / CLDN6, CA19-9, DPEP3, AGS-16, IGF1R, IGF2R, VEGFR1, VEGFR2, VEGFR3, PDGFR-a, PDGFR-p, EGFR, EGFRvIII, ENPP3, FcRH5, FRa, KAAG1, LIV-1, Mesothelin, cMet, ROR1, SLTRK6, TF, BMPR1B, E16, TOP1, STEAP1, 0772P, MUC16, Napi3b, Sema 5b, PSCA hIg, ETBR, RNF124, prostate cancer-associated gene 1, TrpM4, teratocarcinoma-derived growth factor 1, C3DR, FcRH2, NCA, MDP, IL20R-a, Brevican, EphB2R, ASLG659, prostate stem cell antigen precursor, GEDA, BAFF-R, CXCR5, HLA-DOB, P2X5, LY64, FcRH1, IRTA2, TENB2, integrin a5p6, integrin a4p7, FGF2, FGFR1, FGFR2, FGFR3, FGFR4, PSMA, Somatostatin receptor, RANK, SLAMF7, ITGB6, CEACAM5, CA9, EGFRvlll, IL2RA, AXL receptor tyrosine kinase, TGF-pR, TNFRSF8, cancer / testis-associated antigens, CLEC14A, GRP78, stem cell-specific antigens, ASG-5, PRR4, GUCY2C, SLC39A6, TPBG, tumor-associated antigen CA242, FOLR1, GPNMB, HAVCR1, prostate tumor target Mindin, VTCN1, PTK7 protein tyrosine kinase 7, macrophage stimulating 1 receptor, TACSTD2, CA6, DLL3, DLL4, EpCAM, FAP, DKK-1, Endoglin, VCAM1, GPC3, DR5, ASCT2, B7H1, B7H3, B7H4. In certain embodiments, the tumor-associated antigen and immune cell antigen are T cell co-inhibitory molecules. In some embodiments, the antibody or antigen-binding fragment thereof specifically binds to a tumor-associated antigen selected from PD-L1, PD-L2, CD47, CD80, CD86, HVEM, UL144, CD155, CD112, CD113, galectin-1, galectin-3, galectin 9, CD48, LIGHT, BTLA, and CD160. In some embodiments, the tumor-associated antigen is a molecule that binds to a T cell molecule selected from BTLA, Tim-3, PD-1, CTLA-4, TIGIT, CD244, and CD223. In some embodiments, the antibody is an anti-PD-L1 antibody, such as atezolizumab, durvalumab, avelumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-PD-1 antibody, such as nivolumab, pembrolizumab, cemiplimab, anti-mouse PD-1 antibody clone J43, anti-mouse PD-1 antibody clone RMP1-14, mouse anti-PD-1 antibody clone EH12, ANB011, MDX-1106, AMP-514, AMP-224, or pidilizumab. In some embodiments, the anti-PD-1 antibody is pembrolizumab or nivolumab. In some embodiments, the antibody is an anti-CTLA-4 antibody, such as ipilimumab, clone 9H10, tremelimumab, or clone BNI3. In some embodiments, the antibody is an anti-CD47 antibody, such as Hu5F9-G4, IBI188, CC-90002, ZL1201, TTI-621, AO-176, SGN-CD47M antibody, ALX148 antigen-binding domain, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to a tumor-associated antigen that is a growth factor receptor (GFR). In certain embodiments, the tumor-associated antigen is an EGFR / ErbB / HER family GFR. In some embodiments, the tumor-associated antigen is selected from EGFR / HER1 (ErbB1), HER2 / c-Neu (ErbB2), Her3 (ErbB3), and Her4 (ErbB4) receptors. In certain embodiments, the tumor-associated antigen is an IGFR family GFR. In some embodiments, the cancer-associated tumor antigen is an IGF1R or IGF2R receptor. In certain embodiments, the tumor-associated antigen is a TGF-pR (TPR) family GFR. In some embodiments, the cancer-associated tumor antigen is a TPR I or TPR II receptor. In certain embodiments, the tumor-associated antigen is a VEGFR family GFR. In some embodiments, the cancer-associated tumor antigen is a VEGFR1, VEGFR2, or VEGFR3 receptor. In certain embodiments, the tumor-associated antigen is a PDGFR family GFR. In some embodiments, the cancer-associated tumor antigen is a PDGFR-a or PDGFR-P receptor. In certain embodiments, the tumor-associated antigen is a FGFR family GFR. In some embodiments, the cancer-associated tumor antigen is a FGFR1, FGFR2, FGFR3, or FGFR4 receptor. In some embodiments, the antibody is an anti-EGFR / HER1 (ErbB1) antibody, such as cetuximab, panitumumab, necitumumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-HER2 (ErbB2) antibody, such as trastuzumab, pertuzumab, or an antigenbinding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-VEGFR2 antibody, such as ramucirumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-PDGFR-a antibody, such as olaratumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to a lymphoma-associated antigen. In certain embodiments, the lymphoma-associated antigen is CD20, CD30, CD19 / CD3, CD22, or CD33. In some embodiments, the antibody is an anti-CD20 antibody, such as rituximab, ibritumomab, ofatumumab, obinutuzumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-CD30 antibody, such as brentuximab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-CD19 / CD3 antibody, such as blinatumomab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-CD22 antibody, such as inotuzumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-CD33 antibody, such as gemtuzumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to a myeloma-associated antigen. In certain embodiments, the myeloma-associated antigen is SLAMF7 or CD38. In some embodiments, the antibody is an anti-SLAMF7 antibody, such as elotuzumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the antibody is an anti-CD38 antibody, such as daratumumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to a blastoma-associated antigen. In certain embodiments, the blastoma-associated antigen is GD2. In some embodiments, the antibody is an anti-GD2 antibody, such as dinutuximab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to RANK ligand. In some embodiments, the antibody is an anti-RANK ligand antibody, such as denosumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to TROP2. In some embodiments, the antibody is an anti-TROP2 antibody, such as Sacituzumab and Datopotamab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to Claudin18.2. In some embodiments, the antibody is an anti-Claudin18.2 antibody, such as Zolbetuximab, Osemitamab (TST001), CMG901, ASKB589, ZL-1211, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to Met (also known as c-Met, or hepatocyte growth factor receptor (HGFR)). The Met gene with the pathogenic mutation will encode abnormal Met receptors that transmit aberrant signals, leading to multifaceted effects including cell growth, survival, invasion, metastasis, angiogenesis, etc. Tumors involving Met include non-small cell lung cancer, colorectal cancer, gastric cancer, esophageal cancer, glioma, etc. In some embodiments, the antibody is an anti-Met antibody, such as Onartuzumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to the ephrin receptor Eph, especially the EphA2 receptor. EphA2 is not only a biomarker for malignant characteristics but also an active participant in malignant progression, and has been shown to play an important role in regulating cancer development and tumor progression. Human EphA2 is abundantly expressed in prostate cancer, lung cancer, esophageal cancer, colorectal cancer, cervical cancer, ovarian cancer, breast cancer, and skin cancer, which is associated with poor prognosis in tumor patients, increased metastatic potential, and reduced survival. In some embodiments, the antibody is an anti-EphA2 antibody or antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to Nectin-4. In some embodiments, the antibody is an anti-Nectin-4 antibody, such as Enfortumab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In other embodiments, the antibody or antigen-binding fragment thereof specifically binds to both EGFR and Met (also known as c-Met). In some embodiments, the antibody is a bispecific anti-EGFR and Met antibody, such as Amivantamab, or an antigen-binding fragment thereof, or an antibody or antigen-binding fragment having an amino acid sequence equivalent thereto. In some embodiments, the tumor-associated antigen specifically bound by the antibody or antigen-binding fragment thereof is selected from AXL, B7H1, B7H3, B7H4, BCMA, CD16, CD19, CD22, CD25, CD30, CD32, CD33, CD44, CD64, CD70, CD74, CD79, CD138, CD142, CD276, CDH3, CEACAM5, Claudin 18.2, CLDN9 / CLDN6, DPEP3, EGFR, ENPP3, EphA, FcRH5, FOLR1, FRa, GCPII, HER2, HER3, KAAG1, KIT, LIV-1, Mesothelin, c-Met, MUC1, Nectin-4, PD-L1, PD-L1 / PD-L2, PSMA, ROR1, RPR1, TF, TOP1, TROP2, etc. The corresponding antibodies are commercially available or can be prepared by techniques known in the art. In preferred embodiments, the antibody is one that binds to an antigen that is preferentially expressed or overexpressed in cancer cells, such as HER2 (ErbB2), PD-1, PD-L1, EGFR, TROP2, Claudin 18.2, EphA-2, Nectin-4, and Met, more preferably HER2 (ErbB2), EGFR, TROP2, Claudin 18.2, Nectin-4, or a combination of EGFR and Met. For the tumor-associated antigens mentioned above, the ADC compounds of the present disclosure can treat tumors associated with the expression of the aforementioned antigens. The specific list of tumors is known or can be determined by those skilled in the art based on the prior art. Antibodies immunospecific for tumor-associated antigens can be obtained commercially or produced by any method known to those skilled in the art, e.g., recombinant expression techniques. Nucleotide sequences encoding antibodies immunospecific for cancer cell antigens can be obtained, for example, from GenBank databases or similar databases, literature publications, or by conventional cloning and sequencing. Ab Unit Targeting HER2 In a particularly preferred embodiment, the antibody conjugates provided herein include an antibody or antigen-binding fragment that specifically binds to human HER2 (anti-HER2 antibody), i.e., the antibody portion specifically targets the tumor-associated antigen HER2. Accordingly, in some aspects, the present disclosure provides an antibody-drug conjugate (ADC) comprising an antibody or antigen-binding fragment thereof that specifically binds HER2 as the Ab unit of the ADC. HER2 is the receptor tyrosine protein kinase ErbB2, and overexpression or gene amplification of HER2 is present in approximately 20-30% of breast cancers. Increased HER2 activation triggers multiple downstream pathways, leading to aberrant cancer cell proliferation (Treish I, Schwartz R, Lindley C: Pharmacology and therapeutic use of trastuzumab in breast cancer. Am J Health Syst Pharm. 2000 Nov 15;57(22):2063-76; quiz 2077-9). HER2 is also overexpressed in many other types of cancer, such as gastric cancer, esophageal cancer, colon cancer, rectal cancer, breast cancer, ovarian cancer, cervical cancer, uterine cancer, endometrial cancer, bladder cancer, pancreatic cancer, lung cancer, prostate cancer, osteosarcoma, neuroblastoma, or head and neck cancer. In some embodiments, the antibody or antibody fragment thereof (e.g., antigen-binding fragment) that specifically binds to human HER2 can be selected from trastuzumab, pertuzumab, margetuximab, or HT-19, or an antibody fragment or site-specific mutant thereof, or other anti-human HER2 antibody that recognizes the same epitope or competitively binds to human HER2. Trastuzumab (trade names Herceptin or Herclon) is a humanized anti-human epidermal growth factor receptor 2 monoclonal antibody used for the treatment of HER2-positive breast cancer, gastrointestinal cancer, and gastric cancer. It binds to the juxtamembrane portion of the extracellular domain of the HER2 receptor, and its heavy and light chain variable region amino acid sequences are described in US Patent 5,821,337. It interacts with three loop regions formed by human HER2 residues 557-561, 570-573, and 593-603 (Cho et al., Nature 421: 756-760, 2003), possibly interfering with HER2 signaling by preventing HER2 receptor dimerization, promoting HER2 receptor endocytic destruction, and inhibiting shedding of the extracellular domain (Hudis CA, N Engl J Med. 2007;357(1):39-51). Another important mechanism of action for anti-HER2 antibodies is the mediation of antibody-dependent cellular cytotoxicity (ADCC). In ADCC, the anti-HER2 antibody binds to tumor cells and then recruits immune cells, e.g., macrophages, via Fcc receptor (FcaR) interaction. Trastuzumab received US FDA approval in September 1998 for the treatment of metastatic breast cancer in patients. Pertuzumab (also known as 2C4, Omnitarg, Perjeta) is a humanized monoclonal antibody that binds to the extracellular domain of the HER2 receptor and inhibits HER2 dimerization with other HER receptors. Its heavy and light chain amino acid sequences are described in US Patent 7,560,111. Pertuzumab primarily interacts with residues within the 245-333 region of human HER2, particularly residues His 245, Val 286, Ser 288, Leu 295, His 296, or Lys 311 (Franklin et al., Cancer Cell 5: 317328, 2004). Pertuzumab has been shown to be more effective than trastuzumab in disrupting HER1-HER2 and HER3-HER2 complex formation in breast and prostate cancer cell lines (Agus et al., J Clin Oncol. 2005;23(11):2534-43. Epub Feb 7, 2005). For efficacy, pertuzumab does not require antibody-dependent cellular cytotoxicity, as an intact Fc region is not required for its activity (Agus et al., J Clin Oncol. 2005;23(11):2534-43. Epub Feb 7, 2005). Pertuzumab was approved by the US FDA for use in combination with trastuzumab and docetaxel for the treatment of patients with HER2-positive metastatic breast cancer. Margetuximab (also known as MGAH22) is another anti-HER2 monoclonal antibody (see http: / / www.macrogenics.com / products-margetuximab.html). The Fc region of margetuximab is optimized to increase binding to activating FcaRs. Margetuximab is currently in clinical trials for the treatment of patients with relapsed or refractory advanced breast cancer whose tumors show HER2 expression at the 2+ level by immunohistochemistry and lack evidence of HER2 gene amplification by FISH. HT-19 is another anti-HER2 monoclonal antibody that binds to an epitope on human HER2 different from that of trastuzumab or pertuzumab and has been demonstrated to inhibit HER2 signaling comparably to trastuzumab and, in combination with trastuzumab and pertuzumab, promotes HER2 degradation (Bergstrom D. A. et al., Cancer Res. 2015;75:LB-231). Exemplary HER2-targeting antibodies useful in the ADCs of the present disclosure can be antibodies or antigen-binding fragments comprising all 6 CDR sequences of an antibody selected from the group (preferably, comprising the heavy chain variable region and light chain variable region sequences of an antibody selected from the group): trastuzumab (Herceptin, Genentech, US 6,054,297); ATCC Accession Nos. PTA-10355,  PTA-10356,  PTA-10357, PTA 10358 (US20100119511); ATCC Accession No. CRL-10463 (Genentech); ATCC Accession Nos. HB-12215, HB-12216, CRL 10463, HB-12697; pertuzumab (Genentech, US20110117097); ATCC Accession Nos. HB-12215, HB-12216, CRL 10463, HB-12698 (US20090202546); ATCC Accession Nos. HB-12215, HB-12216 (US20060088523); ATCC Accession Nos. (7C2) HB-12215, (7F3) HB-12216,  (4D5)  CRL-10463,  (2C4)  HB-12697  (US20060018899); TrasGEX (Glycotope: http: / / www.glycotope.conn / pipeline). The present disclosure also contemplates anti-HER2 antibodies disclosed in the following documents: US20110177095, US20100119511, US20110117097, US20090285837,  US20090202546,  US20060088523,  US20060018899,  US2011 / 0159014, US20090187007, US20110217305. > Trastuzumab light chain amino acid sequence (SEQ ID NO: 1) DIQMTQSPSSLSASVGDRVTITCRASQDVNTAVAWYQQKPGKAPKLLIYSASFLYSGVPS RFSGSRSGTDFTLTISSLQPEDFATYYCQQHYTTPPTFGQGTKVEIKRTVAAPSVFIFPP SDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLT LSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC > Trastuzumab heavy chain amino acid sequence (SEQ ID NO: 2) EVQLVESGGGLVQPGGSLRLSCAASGFNIKDTYIHWVRQAPGKGLEWVARIYPTNGYTRY ADSVKGRFTISADTSKNTAYLQMNSLRAEDTAVYYCSRWGGDGFYAMDYWGQGTLVTV SS ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSS GLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGG PSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYN STYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREE MTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRW QQGNVFSCSVMHEALHNHYTQKSLSLSPGK. > Trastuzumab light chain LCDR1 sequence (SEQ ID NO: 3) RASQDVNTAVA > Trastuzumab light chain LCDR2 sequence (SEQ ID NO: 4) SASFLYS > Trastuzumab light chain LCDR3 sequence (SEQ ID NO: 5) QQHYTTPPT > Trastuzumab heavy chain HCDR1 sequence (SEQ ID NO: 6) DTYIH > Trastuzumab heavy chain HCDR2 sequence (SEQ ID NO: 7) RIYPTNGYTRYADSVKG > Trastuzumab heavy chain HCDR3 sequence (SEQ ID NO: 8) WGGDGFYAMDY > Trastuzumab light chain variable region VL (SEQ ID NO: 9) DIQMTQSPSSLSASVGDRVTITCRASQDVNTAVAWYQQKPGKAPKLLIYSASFLYSGVPS RFSGSRSGTDFTLTISSLQPEDFATYYCQQHYTTPPTFGQGTKVEIK > Trastuzumab heavy chain variable region VH (SEQ ID NO: 10) EVQLVESGGGLVQPGGSLRLSCAASGFNIKDTYIHWVRQAPGKGLEWVARIYPTNGYTRY ADSVKGRFTISADTSKNTAYLQMNSLRAEDTAVYYCSRWGGDGFYAMDYWGQGTLVTV SS In one embodiment, the antibody portion used in the ADC of the present disclosure comprises all 6 CDR sequences of trastuzumab. In another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain variable region sequence and the light chain variable region sequence of trastuzumab. In yet another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain sequence and the light chain sequence of trastuzumab. In some embodiments, the Ab unit of the ADC of the present disclosure comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 10 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 9, and preferably, wherein the CDRs are defined according to Kabat or IMGT or a combination thereof. In some embodiments, the Ab unit of the ADC of the present disclosure comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 6, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 7, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 8, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 3, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 4, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 5. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region, wherein the heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 10, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a light chain variable region, wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 9, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 10, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 9. In some embodiments, the Ab unit of the ADC of the present disclosure preferably further comprises an antibody heavy chain constant region and / or light chain constant region. Preferably, the heavy chain constant region is a heavy chain constant region derived from a human immunoglobulin. Preferably, the light chain constant region is a light chain constant region derived from a human immunoglobulin. In some aspects, the heavy chain constant region comprised in the Ab unit can be of any isotype or subtype, e.g., an IgG1, IgG2, IgG3, or IgG4 isotype heavy chain constant region, and preferably an IgG1, IgG2, or IgG4 heavy chain constant region, especially a human IgG1 heavy chain constant region. In further aspects, the light chain constant region comprised in the Ab unit can be a k light chain constant region or a X light chain constant region, especially a human k light chain constant region. In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human IgG1 heavy chain constant region. Preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 11, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 11, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 11. An exemplary amino acid sequence of a human IgG1 heavy chain constant region (SEQ ID NO: 11) ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSS GLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGG PSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYN STYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREE MTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRW QQGNVFSCSVMHEALHNHYTQKSLSLSPGK In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human k light chain constant region. Preferably, the light chain constant region comprises the amino acid sequence of SEQ ID NO: 12, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 12, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 12. An exemplary amino acid sequence of a human k light chain constant region (SEQ ID NO: 12) RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDS KDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC In some embodiments, the Ab unit of the ADC of the present disclosure is a full-length antibody comprising a heavy chain constant region and a light chain constant region. In some embodiments, the Ab unit is a tetrameric structure formed by two light chains and two heavy chains. In further embodiments, the Ab unit is an IgG antibody, especially an IgG1 antibody. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the heavy chain comprises the amino acid sequence shown in SEQ ID NO: 2, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof. In other preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the light chain comprises the amino acid sequence shown in SEQ ID NO: 1, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some more preferred embodiments, the Ab unit of the ADC of the present disclosure comprises: (a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 2, and (b) a light chain comprising the amino acid sequence of SEQ ID NO: 1. Ab Unit Targeting TROP2 In a particularly preferred embodiment, the antibody conjugates provided herein include an antibody or antigen-binding fragment that specifically binds to human TROP2 (anti-TROP2 antibody), i.e., the antibody portion specifically targets the tumor-associated antigen TROP2. Accordingly, in some aspects, the present disclosure provides an antibody-drug conjugate (ADC) comprising an antibody or antigen-binding fragment thereof that specifically binds TROP2 as the Ab unit of the ADC. Trophoblast cell surface antigen 2 (TROP2), also known as tumor-associated calcium signal transducer 2 (TACSTD2), is a type I transmembrane cell surface glycoprotein. The sequence of human TROP2 can be obtained from UniProtKB Accession No. P09758. It has been established that TROP2 is overexpressed in many solid tumors, including but not limited to various human epithelial cancers, e.g., cervical cancer, endometrial cancer, breast cancer, urothelial cancer, lung cancer, gastric cancer, prostate cancer, colorectal cancer, and pancreatic cancer. Moreover, TROP2 can play a role in tumor cell proliferation, invasion, migration, apoptosis, and therapeutic resistance by binding to or interacting with various molecules. These characteristics make TROP2 an attractive pan-cancer target for cancer therapy. Ying Wen et al., A literature review of the promising future of TROP2: a potential drug therapy target, Ann Transl Med. 2022 Dec; 10(24): 1403, doi: 10.21037 / atm-22-5976. Antibodies targeting human TROP2 useful in the ADCs of the present disclosure can be prepared using antibody preparation techniques known in the art. For example, anti-TROP2 antibodies can be obtained by immunizing animals with human TROP2 (UniProtKB Accession No. P09758) or a polypeptide comprising the amino acid sequence of the extracellular domain of TROP2, harvesting antibodies from the immunized animals, and purifying and preferably humanizing them. Furthermore, fully human sequence anti-human TROP2 antibodies can be obtained using yeast display libraries expressing human immunoglobulin sequences, transgenic animals, or the like. In some embodiments, the antibody or antibody fragment thereof (e.g., antigen-binding fragment) that specifically binds to human TROP2 can be selected from Sacituzumab, Datopotamab, or an antibody fragment thereof, or other anti-human TROP2 antibody that recognizes the same epitope or competitively binds to human TROP2. Sacituzumab, also known as sacituzumab, is a humanized form of the murine monoclonal antibody RS7 developed by Immunomedics, and is a humanized IgG1K monoclonal antibody targeting TROP2. This antibody can directly bind to TROP2-expressing cancer cells and trigger antibody internalization. The sequence of Sacituzumab can be found in US10179171B2. Datopotamab is an IgG1-type anti-TROP2 antibody. This antibody was generated by humanizing a mouse mAb that specifically binds to human TROP2. The sequence of Datopotamab can be found in Daisuke Okajima et al., Datopotamab Deruxtecan, a Novel TROP2-directed Antibody--drug Conjugate, Demonstrates Potent Antitumor Activity by Efficient Drug Delivery to Tumor Cells, Mol Cancer Ther (2021) 20 (12): 2329-2340. Exemplary antibodies targeting human TROP2 useful in the ADCs of the present disclosure can be antibodies or antigen-binding fragments comprising all 6 CDR sequences of an antibody selected from the group (preferably, comprising the heavy chain variable region and light chain variable region sequences of an antibody selected from the group): Sacituzumab and Datopotamab. The present disclosure also contemplates anti-human TROP2 antibodies disclosed in the following documents: WO2010089782A1; US 2021 / 0393792 A1; WO2008 / 144891, WO2011 / 145744, WO2011 / 155579, WO2013 / 077458, WO2003 / 074566, WO2011 / 068845, WO2013 / 068946, US 2023 / 0270870 A1. >Sacituzumab light chain amino acid sequence (SEQ ID NO: 13) DIQLTQSPSSLSASVGDRVSITCKASQDVSIAVAWYQQKPGKAPKLLIYSASYRYTGVPDRFS GSGSGTDFTLTISSLQPEDFAVYYCQQHYITPLTFGAGTKVEIK RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDS KDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC >Sacituzumab heavy chain amino acid sequence (SEQ ID NO: 14) QVQLQQSGSELKKPGASVKVSCKASGYTFTNYGMNWVKQAPGQGLKWMGWINTYTGEP TYTDDFKGRFAFSLDTSVSTAYLQISSLKADDTAVYFCARGGFGSSYWYFDVWGQGSLVTV SS ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGL YSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVF LFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYR VVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQ VSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVF SCSVMHEALHNHYTQKSLSLSPGK >Sacituzumab light chain LCDR1 sequence (SEQ ID NO: 15) KASQDVSIAVA >Sacituzumab light chain LCDR2 sequence (SEQ ID NO: 16) SASYRYT >Sacituzumab light chain LCDR3 sequence (SEQ ID NO: 17) QQHYITPLT >Sacituzumab heavy chain HCDR1 sequence (SEQ ID NO: 18) NYGMN >Sacituzumab heavy chain HCDR2 sequence (SEQ ID NO: 19) WINTYTGEPTYTDDFKG >Sacituzumab heavy chain HCDR3 sequence (SEQ ID NO: 20) GGFGSSYWYFDV >Sacituzumab light chain variable region VL (SEQ ID NO: 21) DIQLTQSPSSLSASVGDRVSITCKASQDVSIAVAWYQQKPGKAPKLLIYSASYRYTGVPDRFS GSGSGTDFTLTISSLQPEDFAVYYCQQHYITPLTFGAGTKVEIK >Sacituzumab heavy chain variable region VH (SEQ ID NO: 22) QVQLQQSGSELKKPGASVKVSCKASGYTFTNYGMNWVKQAPGQGLKWMGWINTYTGEP TYTDDFKGRFAFSLDTSVSTAYLQISSLKADDTAVYFCARGGFGSSYWYFDVWGQGSLVTV SS In one embodiment, the antibody portion used in the ADC of the present disclosure comprises all 6 CDR sequences of Sacituzumab or Datopotamab. In another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain variable region sequence and the light chain variable region sequence of Sacituzumab or Datopotamab. In yet another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain sequence and the light chain sequence of Sacituzumab or Datopotamab. In some embodiments, the Ab unit of the ADC of the present disclosure comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 22 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 21, and preferably, wherein the CDRs are defined according to Kabat or IMGT or a combination thereof. In some embodiments, the Ab unit of the ADC of the present disclosure comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 18, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 19, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 20, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 15, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 16, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 17. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region, wherein the heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 22, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a light chain variable region, wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 21, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 22, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 21. In some embodiments, the Ab unit of the ADC of the present disclosure preferably further comprises an antibody heavy chain constant region and / or light chain constant region. Preferably, the heavy chain constant region is a heavy chain constant region derived from a human immunoglobulin. Preferably, the light chain constant region is a light chain constant region derived from a human immunoglobulin. In some aspects, the heavy chain constant region comprised in the Ab unit can be of any isotype or subtype, e.g., an IgG1, IgG2, IgG3, or IgG4 isotype heavy chain constant region, and preferably an IgG1, IgG2, or IgG4 heavy chain constant region, especially a human IgG1 heavy chain constant region. In further aspects, the light chain constant region comprised in the Ab unit can be a k light chain constant region or a X light chain constant region, especially a human k light chain constant region. In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human IgG1 heavy chain constant region. Preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 23, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 23, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 23. An exemplary amino acid sequence of a human IgG1 heavy chain constant region (SEQ ID NO: 23) ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQ SSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGG PSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYN STYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEM TKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQ QGNVFSCSVMHEALHNHYTQKSLSLSPGK In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human k light chain constant region. Preferably, the light chain constant region comprises the amino acid sequence of SEQ ID NO: 12, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 12, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, the Ab unit of the ADC of the present disclosure is a full-length antibody comprising a heavy chain constant region and a light chain constant region. In some embodiments, the Ab unit is a tetrameric structure formed by two light chains and two heavy chains. In further embodiments, the Ab unit is an IgG antibody, especially an IgG1 antibody. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the heavy chain comprises the amino acid sequence shown in SEQ ID NO: 14, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof. In other preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the light chain comprises the amino acid sequence shown in SEQ ID NO: 13, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some more preferred embodiments, the Ab unit of the ADC of the present disclosure comprises: (a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 14, and (b) a light chain comprising the amino acid sequence of SEQ ID NO: 13. Cancers that can be treated with the TROP2-targeting ADCs of the present disclosure include, but are not limited to, adenocarcinoma, squamous cell carcinoma, non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC), colorectal cancer, gastric adenocarcinoma, esophageal cancer, hepatocellular carcinoma, ovarian epithelial cancer, breast cancer, metastatic breast cancer, triple-negative breast cancer (TNBC), prostate cancer, hormone-refractory prostate cancer, pancreatic ductal adenocarcinoma, head and neck cancer, renal cell carcinoma, bladder tumor, cervical cancer, endometrial cancer, uterine cancer, follicular thyroid cancer, glioblastoma multiforme. Ab Unit Targeting Claudin18.2 In a particularly preferred embodiment, the antibody conjugates provided herein include an antibody or antigen-binding fragment that specifically binds to human Claudin18.2 (anti-Claudin18.2 antibody), i.e., the antibody portion specifically targets the tumor-associated antigen Claudin18.2. Accordingly, in some aspects, the present disclosure provides an antibody-drug conjugate (ADC) comprising an antibody or antigen-binding fragment thereof that specifically binds Claudin18.2 as the Ab unit of the ADC. Claudin18.2 (also abbreviated as CLDN18.2) belongs to the Claudin family of tight junction membrane proteins. Sequences of human and various mammalian Claudin18.2 can be found in UniProtKB. For example, the human Claudin18.2 sequence can be found under UniProtKB Accession No. P56856-2. The expression of this protein in healthy tissues is mainly restricted to differentiated gastric mucosal epithelial cells, but it exhibits aberrant overexpression in a range of malignancies, particularly digestive system malignancies. Therefore, Claudin18.2 has been proposed as a promising target for developing antibody-based ADC cancer therapeutics. Daisuke Kyuno et al., Claudin-18.2 as a therapeutic target in cancers: cumulative findings from basic research and clinical trials, Tissue Barriers. 2022; 10(1): 1967080. doi: 10.1080 / 21688370.2021.1967080; Jinxia Chen, Targeting CLDN18.2 in cancers of the gastrointestinal tract: New drugs and new indications, Front Oncol. 2023; 13: 1132319, doi: 10.3389 / fonc.2023.1132319. Antibodies targeting human Claudin18.2 useful in the ADCs of the present disclosure can be prepared using antibody preparation techniques known in the art. For example, anti-Claudin18.2 antibodies can be obtained by immunizing animals with human Claudin18.2 (UniProtKB Accession No. P56856-2) or a polypeptide comprising the amino acid sequence of the extracellular domain of Claudin18.2, harvesting antibodies from the immunized animals, and purifying and preferably humanizing them. Furthermore, fully human sequence anti-human Claudin18.2 antibodies can be obtained using yeast display libraries expressing human immunoglobulin sequences, transgenic animals, or the like. In some embodiments, the antibody or antibody fragment thereof (e.g., antigen-binding fragment) that specifically binds to human Claudin18.2 can be selected from Zolbetuximab, Osemitamab (TST001), CMG901, ASKB589, ZL-1211, or an antibody fragment thereof, or other anti-human Claudin18.2 antibody that recognizes the same epitope or competitively binds to human Claudin18.2. Zolbetuximab (also known as GC-182, IMAB-362, IMAB362, claudiximab) is an IgG1 antibody derived from a murine monoclonal antibody and has been chimerized to display a human IgG1 constant region for clinical use. This antibody can directly bind to CLDN18.2-expressing cancer cells and trigger antibody internalization. The sequence of Zolbetuximab can be found in WO2007059997 and WO2016 / 165762. Osemitamab (TST001) is a high-affinity humanized anti-Claudin18.2 antibody. This antibody has enhanced antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), exhibiting potent anti-tumor activity in tumor xenograft models. The sequence of this antibody can be found in Inxight Drugs and INN (code 11927). CMG901, ASKB589, ZL-1211 are exemplary anti-human CLDN18.2 antibodies currently in clinical       trials.       See       DOI:       10.1200 / JCO.2023.41.4_suppl.352;       DOI: 10.1200 / JCO.2023.41.4_suppl.397; DOI: 10.1200 / JCO.2023.41.16_suppl.2537. Exemplary antibodies targeting human CLDN18.2 useful in the ADCs of the present disclosure can be antibodies or antigen-binding fragments comprising all 6 CDR sequences of an antibody selected from the group (preferably, comprising the heavy chain variable region and light chain variable region sequences of an antibody selected from the group): Zolbetuximab, Osemitamab (TST001), and CMG901. The present disclosure also contemplates anti-human Claudin18.2 antibodies disclosed in the following documents: WO2007059997A1, CN107667118A, WO2016 / 166122, US11555070B2, WO2020 / 135674,  WO2018 / 006882,  CN109762067,  WO2019 / 242505,  WO2020 / 038404, WO2020 / 043044,  WO2020 / 063988,  WO2020 / 082209,  WO2020 / 018852,  WO2020 / 023679, WO2020 / 135674,  WO2020 / 135201,  WO2020 / 139956,  WO2020 / 025792,  WO2020160560, CN111808194, and WO2020200196. > Zolbetuximab light chain amino acid sequence (SEQ ID NO: 24) DIVMTQSPSSLTVTAGEKVTMSCKSSQSLLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRE SGVPDRFTGSGSGTDFTLTISSVQAEDLAVYYCQNDYSYPFTFGSGTKLEIK RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDS KDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC > Zolbetuximab heavy chain amino acid sequence (SEQ ID NO: 25) QVQLQQPGAELVRPGASVKLSCKASGYTFTSYWINWVKQRPGQGLEWIGNIYPSDSYTNY NQKFKDKATLTVDKSSSTAYMQLSSPTSEDSAVYYCTRSWRGNSFDYWGQGTTLTVSS ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGL YSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVF LFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYR VVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQ VSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVF SCSVMHEALHNHYTQKSLSLSPGK > Zolbetuximab light chain LCDR1 sequence (SEQ ID NO: 26) KSSQSLLNSGNQKNYLT > Zolbetuximab light chain LCDR2 sequence (SEQ ID NO: 27) WASTRES > Zolbetuximab light chain LCDR3 sequence (SEQ ID NO: 28) QNDYSYPFT > Zolbetuximab heavy chain HCDR1 sequence (SEQ ID NO: 29) SYWIN > Zolbetuximab heavy chain HCDR2 sequence (SEQ ID NO: 30) NIYPSDSYTNYNQKFKD > Zolbetuximab heavy chain HCDR3 sequence (SEQ ID NO: 31) SWRGNSFDY > Zolbetuximab light chain variable region VL (SEQ ID NO: 32) DIVMTQSPSSLTVTAGEKVTMSCKSSQSLLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRE SGVPDRFTGSGSGTDFTLTISSVQAEDLAVYYCQNDYSYPFTFGSGTKLEIK > Zolbetuximab heavy chain variable region VH (SEQ ID NO: 33) QVQLQQPGAELVRPGASVKLSCKASGYTFTSYWINWVKQRPGQGLEWIGNIYPSDSYTNY NQKFKDKATLTVDKSSSTAYMQLSSPTSEDSAVYYCTRSWRGNSFDYWGQGTTLTVSS In one embodiment, the antibody portion used in the ADC of the present disclosure comprises all 6 CDR sequences of Zolbetuximab. In another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain variable region sequence and the light chain variable region sequence of Zolbetuximab. In yet another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain sequence and the light chain sequence of Zolbetuximab. In some embodiments, the Ab unit of the ADC of the present disclosure comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 33 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 32, and preferably, wherein the CDRs are defined according to Kabat or IMGT or a combination thereof. In some embodiments, the Ab unit of the ADC of the present disclosure comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 29, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 30, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 31, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 26, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 27, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 28. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region, wherein the heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 33, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a light chain variable region, wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 32, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 33, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 32. In some embodiments, the Ab unit of the ADC of the present disclosure preferably further comprises an antibody heavy chain constant region and / or light chain constant region. Preferably, the heavy chain constant region is a heavy chain constant region derived from a human immunoglobulin. Preferably, the light chain constant region is a light chain constant region derived from a human immunoglobulin. In some aspects, the heavy chain constant region comprised in the Ab unit can be of any isotype or subtype, e.g., an IgG1, IgG2, IgG3, or IgG4 isotype heavy chain constant region, and preferably an IgG1, IgG2, or IgG4 heavy chain constant region, especially a human IgG1 heavy chain constant region. In further aspects, the light chain constant region comprised in the Ab unit can be a k light chain constant region or a X light chain constant region, especially a human k light chain constant region. In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human IgG1 heavy chain constant region. Preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 34, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 34, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 34. An exemplary amino acid sequence of a human IgG1 heavy chain constant region (SEQ ID NO: 34) ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQS SGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPS VFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNST YRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTK NQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGN VFSCSVMHEALHNHYTQKSLSLSPGK In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human k light chain constant region. Preferably, the light chain constant region comprises the amino acid sequence of SEQ ID NO: 12, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 12, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, the Ab unit of the ADC of the present disclosure is a full-length antibody comprising a heavy chain constant region and a light chain constant region. In some embodiments, the Ab unit is a tetrameric structure formed by two light chains and two heavy chains. In further embodiments, the Ab unit is an IgG antibody, especially an IgG1 antibody. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the heavy chain comprises the amino acid sequence shown in SEQ ID NO: 25, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof. In other preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the light chain comprises the amino acid sequence shown in SEQ ID NO: 24, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some more preferred embodiments, the Ab unit of the ADC of the present disclosure comprises: (a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 25, and (b) a light chain comprising the amino acid sequence of SEQ ID NO: 24. Cancers that can be treated with the Claudin18.2-targeting ADCs of the present disclosure include, but are not limited to, various digestive tract cancers, such as gastric cancer (GC), gastroesophageal junction (GEJ) cancer, esophageal cancer, and pancreatic cancer. Ab Unit Targeting EGFR In a particularly preferred embodiment, the antibody conjugates provided herein include an antibody or antigen-binding fragment that specifically binds to human EGFR (anti-EGFR antibody), i.e., the antibody portion specifically targets the tumor-associated antigen EGFR. Accordingly, in some aspects, the present invention provides an antibody-drug conjugate (ADC) comprising an antibody or antigen-binding fragment thereof that specifically binds EGFR as the Ab unit of the ADC. Epidermal growth factor receptor, also abbreviated herein as EGFR, is a member of the epidermal growth factor receptor (HER) family, encoded by the c-erbB proto-oncogene (also known as HER-1 or Erb-B1). Sequences of human and various mammalian EGFR can be found in UniProtKB. For example, the human EGFR sequence can be found under UniProtKB Accession No. P00533. EGFR is overexpressed in many solid tumors, including lung cancer, head and neck cancer, breast cancer, kidney cancer, gastric cancer, colon cancer, pancreatic cancer, ovarian cancer, prostate cancer, and bladder cancer; and EGFR can induce tumor proliferation through homodimerization. Currently, EGFR has been proposed as a promising target for antibody-based cancer therapeutics. To date, five EGFR-targeting monoclonal antibodies have been approved for clinical cancer treatment, namely cetuximab (Erbitux®), panitumumab (Vectibix®), nimotuzumab (BIOMAB-EGFR®), necitumumab (Portrazza®), and amivantamab (amivantamab-vmjw; Rybrevant®). In addition, three EGFR-based ADC drugs are in clinical trials. However, no EGFR-based ADC has yet been approved for therapy. See Jinfeng Yu et al., Antibody-Drug Conjugates Targeting the Human Epidermal Growth Factor Receptor Family in Cancers, Front Mol Biosci. 2022; 9: 847835, doi: 10.3389 / fmolb.2022.847835. Various anti-EGFR monoclonal antibodies have been developed for binding to the extracellular domain of this receptor to block receptor-ligand interaction or its dimerization. These antibodies are all suitable for use in the present invention. Furthermore, antibodies targeting human EGFR useful in the ADCs of the present invention can also be prepared using antibody preparation techniques known in the art. For example, anti-EGFR antibodies can be obtained by immunizing animals with human EGFR (UniProtKB Accession No. P00533) or a polypeptide comprising the amino acid sequence of the extracellular domain of EGFR, harvesting antibodies from the immunized animals, and purifying and preferably humanizing them. Furthermore, fully human sequence anti-human EGFR antibodies can be obtained using yeast display libraries expressing human immunoglobulin sequences, transgenic animals, or the like. The antibody targeting human EGFR used in the ADCs of the present invention can be a monospecific antibody that binds EGFR. In some cases, the antibody targeting human EGFR used in the ADCs of the present invention can also be a multispecific antibody, especially a bispecific antibody, such as one targeting EGFR and MET; or one targeting MUC1 and EGFR. In some embodiments, the anti-human EGFR antibody or antibody fragment thereof (e.g., antigen-binding fragment) used in the ADCs of the present invention can be selected from cetuximab (Erbitux®), panitumumab (Vectibix®), nimotuzumab (BIOMAB-EGFR®), necitumumab (Portrazza®),    depatuxizumab    (ABT-806),    NECITUMUMAB,    IZALONTAMAB, BAFISONTAMAB, Petosemtamab, PIMURUTAMAB, FUTUXIMAB, MODOTUXIMAB (Zatuximab), or an antibody fragment thereof, or other anti-human EGFR antibody that recognizes the same epitope or competitively binds to human EGFR. The sequences of the aforementioned antibodies can be found in Inxight Drugs and International Nonproprietary Names (INN) codes 7906, 8499, 8545, 9083, 11030, 10263, 9083, 12022, 11851,11136,11309,9612,and 9613. Cetuximab (Erbitux®) is a recombinant chimeric human / murine IgG1 monoclonal antibody. This antibody binds to the extracellular domain of inactive EGFR with an affinity far greater than that of endogenous ligands, competitively blocking ligand-receptor binding, blocking the agonistic effect of ligands on the receptor, and can trigger EGFR internalization, downregulating EGFR expression levels on the cell membrane. Furthermore, this antibody can activate antibody-dependent cell-mediated cytotoxicity (ADCC), producing further cell-killing effects. The sequence of cetuximab can be found in WO2007092453 and INN code 7906. Panitumumab (Vectibix®) is a recombinant humanized IgG2 monoclonal antibody. Panitumumab specifically binds to EGFR on tumor cells and competitively inhibits the binding of EGFR ligands. Preclinical studies have shown that the binding of panitumumab to EGFR prevents ligand-induced receptor autophosphorylation and receptor-associated kinase activation, thereby inhibiting cell growth, inducing apoptosis, reducing the production of pro-inflammatory cytokines and vascular growth factors, and can induce EGFR internalization. The sequence of panitumumab can be found in INN code 8499. Exemplary antibodies targeting human EGFR useful in the ADCs of the present invention can be antibodies or antigen-binding fragments comprising all 6 CDR sequences of an antibody selected from the group (preferably, comprising the heavy chain variable region and light chain variable region sequences of an antibody selected from the group): cetuximab, panitumumab, nimotuzumab, necitumumab, depatuxizumab, NECITUMUMAB, IZALONTAMAB, BAFISONTAMAB, Petosemtamab, PIMURUTAMAB, FUTUXIMAB, and MODOTUXIMAB. The present invention also contemplates anti-human EGFR antibodies disclosed in the following documents: WO2023040941A1, WO2022271722A1, WO2022159576A1, WO2022128716A1, WO2022105878A1, WO2020233534A1, WO2019035630A2, WO2017214282A1, WO2017136581A1, WO2017008169A1, WO2014143765A8, WO2012143495A3. WO2021247798A1, WO2020130125A1, WO2019035630A3, WO2017214301A1, WO2017076492A1, WO2016065456A1, WO2014152199A1, WO2022104697A1, WO2019046858A1, WO2018098035A1, WO2017161206A1, WO2017060322A3, WO2015143382A1, WO2014094355A1, WO2021066869A1, WO2019046859A1, WO2017214233A1, WO2017139623A1, WO2017025458A1, WO2014143765A1, and WO2012143495A2, > Cetuximab light chain amino acid sequence (SEQ ID NO: 35) DILLTQSPVILSVSPGERVSFSCRASQSIGTNIHWYQQRTNGSPRLLIKYASESISGIPSRFSGSG SGTDFTLSINSVESEDIADYYCQQNNNWPTTFGAGTKLELK RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDS KDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC > Cetuximab heavy chain amino acid sequence (SEQ ID NO: 36) QVQLKQSGPGLVQPSQSLSITCTVSGFSLTNYGVHWVRQSPGKGLEWLGVIWSGGNTDYN TPFTSRLSINKDNSKSQVFFKMNSLQSNDTAIYYCARALTYYDYEFAYWGQGTLVTVSA ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGL YSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVF LFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYR VVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQ VSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVF SCSVMHEALHNHYTQKSLSLSPGK > Cetuximab light chain LCDR1 sequence (SEQ ID NO: 37) RASQSIGTNIH > Cetuximab light chain LCDR2 sequence (SEQ ID NO: 38) YASESIS > Cetuximab light chain LCDR3 sequence (SEQ ID NO: 39) QQNNNWPTT > Cetuximab heavy chain HCDR1 sequence (SEQ ID NO: 40) NYGVH > Cetuximab heavy chain HCDR2 sequence (SEQ ID NO: 41) VIWSGGNTDYNTPFTS > Cetuximab heavy chain HCDR3 sequence (SEQ ID NO: 42) ALTYYDYEFAY > Cetuximab light chain variable region VL (SEQ ID NO: 43) DILLTQSPVILSVSPGERVSFSCRASQSIGTNIHWYQQRTNGSPRLLIKYASESISGIPSRFSGSG SGTDFTLSINSVESEDIADYYCQQNNNWPTTFGAGTKLELK > Cetuximab heavy chain variable region VH (SEQ ID NO: 44) QVQLKQSGPGLVQPSQSLSITCTVSGFSLTNYGVHWVRQSPGKGLEWLGVIWSGGNTDYN TPFTSRLSINKDNSKSQVFFKMNSLQSNDTAIYYCARALTYYDYEFAYWGQGTLVTVSA In one embodiment, the antibody portion used in the ADC of the present invention comprises all 6 CDR sequences of Cetuximab. In another embodiment, the antibody portion used in the ADC of the present invention comprises the heavy chain variable region sequence and the light chain variable region sequence of Cetuximab. In yet another embodiment, the antibody portion used in the ADC of the present invention comprises the heavy chain sequence and the light chain sequence of Cetuximab. In some embodiments, the Ab unit of the ADC of the present invention comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 44 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 43, and preferably, wherein the CDRs are defined according to Kabat or IMGT or a combination thereof. In some embodiments, the Ab unit of the ADC of the present invention comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 40, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 41, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 42, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 37, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 38, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 39. In one embodiment, the Ab unit of the ADC of the present invention comprises a heavy chain variable region, wherein the heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 44, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In one embodiment, the Ab unit of the ADC of the present invention comprises a light chain variable region, wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 43, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some preferred embodiments, the Ab unit of the ADC of the present invention comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 44, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 43. In some embodiments, the Ab unit of the ADC of the present invention preferably further comprises an antibody heavy chain constant region and / or light chain constant region. Preferably, the heavy chain constant region is a heavy chain constant region derived from a human immunoglobulin. Preferably, the light chain constant region is a light chain constant region derived from a human immunoglobulin. In some aspects, the heavy chain constant region comprised in the Ab unit can be of any isotype or subtype, e.g., an IgG1, IgG2, IgG3, or IgG4 isotype heavy chain constant region, and preferably an IgG1, IgG2, or IgG4 heavy chain constant region, especially a human IgG1 heavy chain constant region. In further aspects, the light chain constant region comprised in the Ab unit can be a k light chain constant region or a X light chain constant region, especially a human k light chain constant region. In some embodiments, the Ab unit of the ADC of the present invention comprises a human IgG1 heavy chain constant region. Preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 34, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 34, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 34. In some embodiments, the Ab unit of the ADC of the present invention comprises a human k light chain constant region. Preferably, the light chain constant region comprises the amino acid sequence of SEQ ID NO: 12, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 12, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, the Ab unit of the ADC of the present invention is a full-length antibody comprising a heavy chain constant region and a light chain constant region. In some embodiments, the Ab unit is a tetrameric structure formed by two light chains and two heavy chains. In further embodiments, the Ab unit is an IgG antibody, especially an IgG1 antibody. In some preferred embodiments, the Ab unit of the ADC of the present invention comprises a heavy chain and a light chain, wherein: the heavy chain comprises the amino acid sequence shown in SEQ ID NO: 36, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof. In other preferred embodiments, the Ab unit of the ADC of the present invention comprises a heavy chain and a light chain, wherein: the light chain comprises the amino acid sequence shown in SEQ ID NO: 35, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some more preferred embodiments, the Ab unit of the ADC of the present invention comprises: (a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 36, and (b) a light chain comprising the amino acid sequence of SEQ ID NO: 35. Cancers that can be treated with the EGFR-targeting ADCs of the present disclosure include, but are not limited to, various primary and metastatic solid tumors, such as lung cancer (e.g., lung adenocarcinoma, lung squamous cell carcinoma, and non-small cell lung cancer), head and neck cancer (e.g., head and neck squamous cell carcinoma), nasopharyngeal cancer, esophageal cancer, biliary tract cancer, colon cancer, colorectal cancer, pancreatic cancer, gastric cancer, and glioblastoma. Ab Unit Targeting EGFR and MET In a particularly preferred embodiment, the antibody conjugates provided herein include an antibody or antigen-binding fragment that specifically binds to human EGFR and MET (also known as c-Met) (anti-EGFR / MET antibody), i.e., the antibody portion specifically targets the tumor-associated antigens EGFR and MET. Accordingly, in some aspects, the present disclosure provides an antibody-drug conjugate (ADC) comprising an antibody or antigen-binding fragment thereof that specifically binds EGFR and MET as the Ab unit of the ADC. Drug resistance is a major challenge for targeted cancer therapies. For example, MET amplification or protein overexpression has been identified as an important mechanism of clinical resistance to EGFR inhibitors. Similarly, emerging evidence suggests that activation of the EGFR pathway may lead to resistance to c-MET-targeted inhibitors. Benedettini, E., et al., Met activation in non-small cell lung cancer is associated with de novo resistance to EGFR inhibitors and the development of brain metastasis. The American journal of pathology, 2010. 177(1): p. 415-423. Bertotti, 2015 Bertotti, A. and F. Sassi, Molecular Pathways: Sensitivity and Resistance to Anti-EGFR Antibodies. Clinical Cancer Research, 2015. Furthermore, co-expression of cMet and EGFR has been observed in various cancers, including non-small cell lung cancer, pancreatic cancer, colorectal cancer, head and neck squamous cell carcinoma, breast cancer, and esophagogastric cancer. Therefore, drug molecules based on multispecific antibodies (such as bispecific antibodies) targeting EGFR and c-MET have been proposed as a promising therapeutic option for EGFR / cMET singlepositive and double-positive tumors. Examples of EGFR / cMET dual-targeting antibodies include, but are not limited to, Amivantamab, AZD9592, Pamvatamig (MCLA-129), Bafisontamab (EMB01), and LY-3164530, which are approved or in clinical development. In some embodiments, the antibody or antibody fragment thereof (e.g., antigen-binding fragment) that specifically binds to human EGFR and MET is selected from: Amivantamab, AZD9592, Pamvatamig (MCLA-129), Bafisontamab (EMB01), and LY-3164530, or an antibody fragment or site-specific mutant thereof, or other anti-human EGFR and MET antibody that recognizes the same epitope or competitively binds to human EGFR and MET. These antibodies can promote internalization at the relevant targets, enter tumor cells, and be degraded, and are therefore suitable drug delivery vehicles. Amivantamab, also known as JNJ-61186372, is an anti-EGFR-MET bispecific antibody. This antibody has an EGFR antibody arm composed of one heavy chain and one light chain, and a MET antibody arm composed of one heavy chain and one light chain, and is a 1+1-type asymmetric IgG-like structure. This antibody binds to EGFR and MET, acts as an EGFR antagonist and MET inhibitor, and induces internalization of EGFR and MET on the cell surface. Amivantamab is indicated for the treatment of various cancers, especially non-small cell lung cancer, with EGFR exon 20 insertion mutations. Patients with non-small cell lung cancer often develop resistance to drugs targeting EGFR and MET alone. The development of amivantamab, by targeting both EGFR and MET, reduces the likelihood of developing resistance and has shown superior efficacy in animal models and clinical trials compared to EGFR inhibitors and MET inhibitors alone. The FDA has approved this antibody for the treatment of patients with metastatic non-small cell lung cancer (NSCLC) harboring EGFR exon 20 insertion mutations who have progressed on or after platinum-based chemotherapy. The antibody sequence of Amivantamab can be found in US20230174677A1 and CAS No. 2171511-581. AZD9592 is currently in Phase 1 clinical studies as a drug molecule based on a MET-EGFR dual-target antibody, applicable to colorectal cancer, head and neck tumors, and non-small cell lung cancer. The bispecific antibody RAA22 / B09-57 targeting EGFR and cMet involved in this drug molecule simultaneously targets both EGFR and c-Met and is a 1+1-type asymmetric bispecific antibody. This antibody exerts its effect by inhibiting hepatocyte growth factor receptor MET and epidermal growth factor receptor EGFR. The antibody sequence of RAA22 / B09-57 can be found in US2023 / 0183358A1. Pamvatamig, also known as MCLA-129, is a 1+1-type asymmetric bispecific antibody. The construction of this bispecific antibody employs DEKK mutations to prevent heavy chain mispairing and uses a common light chain to prevent light chain mispairing. Functionally, MCLA-129 can not only inhibit the phosphorylation of cMet and EGFR in tumors but also reverse tumor resistance to erlotinib. This bispecific antibody is suitable for targeting advanced malignant solid tumors, colorectal cancer, esophageal squamous cell carcinoma, metastatic non-small cell lung cancer, head and neck squamous cell carcinoma, gastric cancer, and advanced non-small cell lung cancer with EGFR mutations. The antibody sequence of Pamvatamig is disclosed in US11773170B2 and CAS No. 2750004-05-6. Bafisontamab (EMB01) is an EGFR and cMet bispecific antibody constructed using the FIT-Ig® bispecific antibody platform. Structurally, EMB-01 is a 2+2-type symmetric bispecific antibody structure. EMB-01 induces significantly stronger antitumor activity in PDX and CDX tumor models than anti-EGFR or anti-c-Met monoclonal antibodies alone and exhibits significant antitumor activity in anti-EGFR monoclonal antibody-resistant tumor models. The antibody sequence of EMB-01 is disclosed in WO2017136820 (as molecule FIT013a) and INN code 11851. LY-3164530 is a bispecific antibody targeting c-MET / EGFR, constructed by fusing an scFv (cetuximab) to the N-terminus of the heavy chain of emibetuzumab (LY2875358), forming a 2+2 symmetric bispecific antibody. This antibody is of the IgG4 subtype and therefore has little or no relevant effector functions such as ADCC. In tumor mouse models, this bispecific antibody exhibits a certain effect in inhibiting tumor cell growth. The antibody sequence of LY-3164530 is disclosed under CAS 2069210-01-9. Exemplary antibodies targeting EGFR and MET useful in the ADCs of the present disclosure can be antibodies or antigen-binding fragments comprising all 6 CDR sequences of an antibody selected from the group that specifically binds EGFR and all 6 CDR sequences that specifically binds MET (preferably, comprising the anti-EGFR heavy and light chain variable region sequences and the anti-MET heavy and light chain variable region sequences of an antibody selected from the group): Amivantamab, AZD9592, Pamvatamig (MCLA-129), Bafisontamab (EMB01), and LY-3164530. The present disclosure also contemplates anti-EGFR and MET antibodies disclosed in the following documents: WO2019031965A1, WO2022104236A2, WO2023069888A1, WO2023122588A2, WO2023172133A1, WO2023172134A1, WO2024002938A1, and WO2024153168A2. > Amivantamab anti-EGFR heavy chain amino acid sequence (SEQ ID NO: 45) QVQLVESGGGVVQPGRSLRLSCAASGFTFSTYGMHWVRQAPGKGLEWVAVIWDDGSYKY YGDSVKGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCARDGITMVRGVMKDYFDYWGQG TLVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPA VLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPEL LGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREE QYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSR EEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFLLYSKLTVDKSR WQQGNVFSCSVMHEALHNHYTQKSLSLSPGK > Amivantamab anti-EGFR light chain amino acid sequence (SEQ ID NO: 46) AIQLTQSPSSLSASVGDRVTITCRASQDISSALVWYQQKPGKAPKLLIYDASSLESGVPSRFS GSESGTDFTLTISSLQPEDFATYYCQQFNSYPLTFGGGTKVEIKRTVAAPSVFIFPPSDEQLKS GTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYE KHKVYACEVTHQGLSSPVTKSFNRGEC > Amivantamab anti-MET heavy chain amino acid sequence (SEQ ID NO: 47) QVQLVQSGAEVKKPGASVKVSCETSGYTFTSYGISWVRQAPGHGLEWMGWISAYNGYTN YAQKLQGRVTMTTDTSTSTAYMELRSLRSDDTAVYYCARDLRGTNYFDYWGQGTLVTVSS ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGL YSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSVF LFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYR VVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQ VSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQQGNVFS CSVMHEALHNHYTQKSLSLSPGK > Amivantamab anti-MET light chain amino acid sequence (SEQ ID NO: 48) DIQMTQSPSSVSASVGDRVTITCRASQGISNWLAWFQHKPGKAPKLLIYAASSLLSGVPSRF SGSGSGTDFTLTISSLQPEDFATYYCQQANSFPITFGQGTRLEIKRTVAAPSVFIFPPSDEQLKS GTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYE KHKVYACEVTHQGLSSPVTKSFNRGEC > Amivantamab anti-EGFR heavy chain HCDR1 amino acid sequence (SEQ ID NO: 49) TYGMH > Amivantamab anti-EGFR heavy chain HCDR2 amino acid sequence (SEQ ID NO: 50) VIWDDGSYKYYGDSVKG > Amivantamab anti-EGFR heavy chain HCDR3 amino acid sequence (SEQ ID NO: 51) DGITMVRGVMKDYFDY > Amivantamab anti-EGFR light chain LCDR1 amino acid sequence (SEQ ID NO: 52) RASQDISSALV > Amivantamab anti-EGFR light chain LCDR2 amino acid sequence (SEQ ID NO: 53) DASSLES > Amivantamab anti-EGFR light chain LCDR3 amino acid sequence (SEQ ID NO: 54) QQFNSYPLT > Amivantamab anti-MET heavy chain HCDR1 amino acid sequence (SEQ ID NO: 55) SYGIS > Amivantamab anti-MET heavy chain HCDR2 amino acid sequence (SEQ ID NO: 56) WISAYNGYTNYAQKLQG > Amivantamab anti-MET heavy chain HCDR3 amino acid sequence (SEQ ID NO: 57) DLRGTNYFDY > Amivantamab anti-MET light chain LCDR1 amino acid sequence (SEQ ID NO: 58) RASQGISNWLA > Amivantamab anti-MET light chain LCDR2 amino acid sequence (SEQ ID NO: 59) AASSLLS > Amivantamab anti-MET light chain LCDR3 amino acid sequence (SEQ ID NO: 60) QQANSFPIT > Amivantamab anti-EGFR heavy chain variable region VH amino acid sequence (SEQ ID NO: 61) QVQLVESGGGVVQPGRSLRLSCAASGFTFSTYGMHWVRQAPGKGLEWVAVIWDDGSYKY YGDSVKGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCARDGITMVRGVMKDYFDYWGQG TLVTVSS > Amivantamab anti-EGFR light chain variable region VL amino acid sequence (SEQ ID NO: 62) AIQLTQSPSSLSASVGDRVTITCRASQDISSALVWYQQKPGKAPKLLIYDASSLESGVPSRFS GSESGTDFTLTISSLQPEDFATYYCQQFNSYPLTFGGGTKVEIK > Amivantamab anti-MET heavy chain variable region VH amino acid sequence (SEQ ID NO: 63) QVQLVQSGAEVKKPGASVKVSCETSGYTFTSYGISWVRQAPGHGLEWMGWISAYNGYTN YAQKLQGRVTMTTDTSTSTAYMELRSLRSDDTAVYYCARDLRGTNYFDYWGQGTLVTVSS > Amivantamab anti-MET light chain variable region VL amino acid sequence (SEQ ID NO: 64) DIQMTQSPSSVSASVGDRVTITCRASQGISNWLAWFQHKPGKAPKLLIYAASSLLSGVPSRF SGSGSGTDFTLTISSLQPEDFATYYCQQANSFPITFGQGTRLEIK In one embodiment, the antibody portion used in the ADC of the present invention comprises all 6 CDR sequences of the anti-EGFR arm and all 6 CDR sequences of the anti-MET arm of Amivantamab. In another embodiment, the antibody portion used in the ADC of the present invention comprises the heavy chain variable region sequence and light chain variable region sequence of the anti-EGFR arm and the heavy chain variable region sequence and light chain variable region sequence of the anti-MET arm of Amivantamab. In yet another embodiment, the antibody portion used in the ADC of the present invention comprises the anti-EGFR heavy chain sequence and light chain sequence and the anti-MET heavy chain sequence and light chain sequence of Amivantamab. In some embodiments, the Ab unit of the ADC of the present invention comprises a first set of complementarity determining regions that bind EGFR and a second set of complementarity determining regions that bind MET, wherein the first set of complementarity determining regions comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 61 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 62, and the second set of complementarity determining regions comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 63 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 64. Preferably, the CDRs are defined according to Kabat or IMGT or a combination thereof. In some embodiments, the Ab unit of the ADC of the present invention comprises a first set of complementarity determining regions that bind EGFR and a second set of complementarity determining regions that bind MET, wherein: The first set of complementarity determining regions comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 49, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 50, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 51, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 52, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 53, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 54; The second set of complementarity determining regions comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 55, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 56, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 57, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 58, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 59, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 60. In one embodiment, the Ab unit of the ADC of the present invention comprises a first heavy chain variable region and a first light chain variable region that bind EGFR and a second heavy chain variable region and a second light chain variable region that bind MET. In some embodiments, the first heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 61, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some embodiments, the first light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 62, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some embodiments, the second heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 63, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some embodiments, the second light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 64, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some embodiments, the Ab unit of the ADC of the present invention comprises a first heavy chain variable region and a first light chain variable region that bind EGFR and a second heavy chain variable region and a second light chain variable region that bind MET, wherein: the first heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 61, and the first light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 62; and the second heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 63, and the second light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 64. In some embodiments, the Ab unit of the ADC of the present disclosure preferably further comprises an antibody heavy chain constant region and / or light chain constant region. Preferably, the heavy chain constant region is a heavy chain constant region derived from a human immunoglobulin. Preferably, the light chain constant region is a light chain constant region derived from a human immunoglobulin. In some aspects, the heavy chain constant region comprised in the Ab unit can be of any isotype or subtype, e.g., an IgG1, IgG2, IgG3, or IgG4 isotype heavy chain constant region, and preferably an IgG1, IgG2, or IgG4 heavy chain constant region, especially a human IgG1 heavy chain constant region. In further aspects, the light chain constant region comprised in the Ab unit can be a k light chain constant region or a X light chain constant region, especially a human k light chain constant region. In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human IgG1 heavy chain constant region. Preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 65 or 66, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 65 or 66, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 65 or 66. An exemplary amino acid sequence of a human IgG1 heavy chain constant region (SEQ ID NO: 65) ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQS SGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPS VFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNST YRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTK NQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFLLYSKLTVDKSRWQQGN VFSCSVMHEALHNHYTQKSLSLSPGK An exemplary amino acid sequence of a human IgG1 heavy chain constant region (SEQ ID NO: 66) ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQS SGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPS VFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNST YRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTK NQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQQGN VFSCSVMHEALHNHYTQKSLSLSPGK In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human k light chain constant region. Preferably, the light chain constant region comprises the amino acid sequence of SEQ ID NO: 12, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 12, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, the Ab unit of the ADC of the present disclosure comprises or consists of a first heavy chain, a first light chain, a second heavy chain, and a second light chain, wherein from N-terminus to C-terminus: - the first heavy chain comprises an anti-EGFR heavy chain variable region and a first heavy chain constant region; - the first light chain comprises an anti-EGFR light chain variable region and a first light chain constant region; - the second heavy chain comprises an anti-MET heavy chain variable region and a second heavy chain constant region; - the second light chain comprises an anti-MET light chain variable region and a second light chain constant region. In some embodiments, the first and second heavy chain constant regions are heavy chain constant regions as defined above, preferably human IgG1 constant regions; the first and second light chain constant regions are light chain constant regions as defined above, preferably human k light chain constant regions. In some embodiments, the first heavy chain constant region comprises or consists of the amino acid sequence of SEQ ID NO: 65, and the second heavy chain constant region comprises or consists of the amino acid sequence of SEQ ID NO: 66. In some embodiments, the first and second light chain constant regions each comprise or consist of the amino acid sequence of SEQ ID NO: 12. In some embodiments, the Ab unit of the ADC of the present disclosure is a full-length antibody comprising a heavy chain constant region and a light chain constant region. In some embodiments, the Ab unit is a tetrameric structure formed by two light chains and two heavy chains. In further embodiments, the Ab unit is an IgG antibody, especially an IgG1 antibody. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a first heavy chain, a first light chain, a second heavy chain, and a second light chain, wherein: the first heavy chain comprises the amino acid sequence shown in SEQ ID NO: 45, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof; and the first light chain comprises the amino acid sequence shown in SEQ ID NO: 46, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto; the second heavy chain comprises the amino acid sequence shown in SEQ ID NO: 47, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof; and the second light chain comprises the amino acid sequence shown in SEQ ID NO: 48, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some more preferred embodiments, the Ab unit of the ADC of the present disclosure comprises: (a) an anti-EGFR heavy chain comprising the amino acid sequence of SEQ ID NO: 45 and an anti-EGFR light chain comprising the amino acid sequence of SEQ ID NO: 46, and (b) an anti-MET heavy chain comprising the amino acid sequence of SEQ ID NO: 47 and an anti-MET light chain comprising the amino acid sequence of SEQ ID NO: 48. Cancers that can be treated with the EGFR and MET-targeting ADCs of the present disclosure are EGFR and / or MET positive cancers, such as solid tumors and hematological tumors, including but not limited to: non-small cell lung cancer, breast cancer, lung cancer, colorectal cancer, pancreatic cancer, ovarian cancer, gastric cancer, prostate cancer, head and neck tumors, liver cancer, bladder cancer, melanoma, esophageal cancer, renal tumors, thyroid cancer, cervical cancer, lymphoma, uterine cancer, skin tumors, colon cancer, sarcoma, leukemia, glioblastoma, etc. Ab Unit Targeting Nectin4 In a particularly preferred embodiment, the antibody conjugates provided herein include an antibody or antigen-binding fragment that specifically binds to human Nectin-4 (anti-Nectin-4 antibody), i.e., the antibody portion specifically targets the tumor-associated antigen Nectin-4. Accordingly, in some aspects, the present disclosure provides an antibody-drug conjugate (ADC) comprising an antibody or antigen-binding fragment thereof that specifically binds Nectin-4 as the Ab unit of the ADC. Nectin-4 (Nectin cell adhesion molecule 4), also known as poliovirus receptor-related (PRR) protein, is a type I transmembrane cell adhesion molecule belonging to the Nectin family. Nectin-4 forms physical connections between adjacent cells and is essential for achieving intercellular communication, migration, and other important cellular processes. The Nectin-4 protein is specifically expressed in embryos and placentas, is expressed at low levels in only a few normal adult tissues (including skin), but is abnormally highly expressed in tumor tissues. The overexpression of Nectin-4 in various tumor cells serves as a marker for cancer recurrence and metastasis and is associated with poor prognosis in various cancers. Cancers overexpressing Nectin-4 include, for example, breast cancer, cervical cancer, ovarian cancer, gastric cancer, esophageal cancer, head and neck cancer, lung cancer, non-small cell lung cancer, melanoma, bladder cancer, thyroid cancer, as well as hepatocellular carcinoma and urothelial carcinoma. Due to the specific expression of the Nectin-4 target, Nectin-4 has become a potential biomarker and promising therapeutic target. See, e.g., Jeffrey L Wong et al., Expert Opin Biol Ther. 2021 May 24;21(7):863-873. doi: 10.1080 / 14712598.2021.1929168, "Targeting nectin-4 by antibody-drug conjugates for the treatment of urothelial carcinoma". Antibodies targeting human Nectin-4 useful in the ADCs of the present disclosure can be prepared using antibody preparation techniques known in the art. For example, anti-Nectin4 antibodies can be obtained by immunizing animals with human Nectin4 (UniProtKB Accession No. Q96NY8) or a polypeptide comprising the amino acid sequence of the extracellular domain of Nectin-4, harvesting antibodies from the immunized animals, and purifying and preferably humanizing them. Furthermore, fully human sequence anti-human Nectin4 antibodies can be obtained using yeast display libraries expressing human immunoglobulin sequences, transgenic animals, or the like. In some embodiments, the antibody or antibody fragment thereof (e.g., antigen-binding fragment) that specifically binds to human Nectin-4 can be selected from Enfortumab, LY4052031, 9MW2821, BAT8007, SBT6290, or an antibody fragment thereof, or other anti-human Nectin4 antibody that recognizes the same epitope or competitively binds to human Nectin4. Exemplary antibodies targeting human Nectin4 useful in the ADCs of the present disclosure can be antibodies or antigen-binding fragments comprising all 6 CDR sequences of an antibody selected from the group (preferably, comprising the heavy chain variable region and light chain variable region sequences of an antibody selected from the group): Enfortumab, LY4052031, 9MW2821, BAT8007, SBT6290. The present disclosure also contemplates anti-human Nectin4 antibodies disclosed in the following documents: WO2012047724, WO2022228406, WO2022228563, WO2024088390, WO2024012536,  WO2024038075,  WO2024017992,  US12049500B2,  US11179473B2, US11292837B2, US10675357B2, CN119013302A. Enfortumab is a monospecific bivalent IgG antibody that targets and binds Nectin4. This antibody can directly bind to Nectin4-expressing cancer cells and trigger antibody internalization. Its sequence can be found in NCATS Inxight Drugs, as well as FDA UNII U1HUE4W970 and CAS NO. 1448664-46-7. > Enfortumab light chain amino acid sequence (SEQ ID NO: 67) DIQMTQSPSSVSASVGDRVTITCRASQGISGWLAWYQQKPGKAPKFLIYAASTLQSGV PSRFSGSGSGTDFTLTISSLQPEDFATYYCQQANSFPPTFGGGTKVEIKRTVAAPSVFIFPPSD EQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLS KADYEKHKVYACEVTHQGLSSPVTKSFNRGEC > Enfortumab heavy chain amino acid sequence (SEQ ID NO: 68) EVQLVESGGGLVQPGGSLRLSCAASGFTFSSYNMNWVRQAPGKGLEWVSYISSSSSTI YYADSVKGRFTISRDNAKNSLSLQMNSLRDEDTAVYYCARAYYYGMDVWGQGTTVTVS SASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSG LYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKRVEPKSCDKTHTCPPCPAPELLGGPSV FLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTY RVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTK NQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQG NVFSCSVMHEALHNHYTQKSLSLSPGK >Enfortumab light chain LCDR1 sequence (SEQ ID NO: 69) RASQGISGWLA >Enfortumab light chain LCDR2 sequence (SEQ ID NO: 70) AASTLQS >Enfortumab light chain LCDR3 sequence (SEQ ID NO: 71) QQANSFPPT >Enfortumab heavy chain HCDR1 sequence (SEQ ID NO: 72) SYNMN >Enfortumab heavy chain HCDR2 sequence (SEQ ID NO: 73) YISSSSSTIYYADSVKG >Enfortumab heavy chain HCDR3 sequence (SEQ ID NO: 74) AYYYGMDV >Enfortumab light chain variable region VL (SEQ ID NO: 75) DIQMTQSPSSVSASVGDRVTITCRASQGISGWLAWYQQKPGKAPKFLIYAASTLQSGV PSRFSGSGSGTDFTLTISSLQPEDFATYYCQQANSFPPTFGGGTKVEIK >Enfortumab heavy chain variable region VH (SEQ ID NO: 76) EVQLVESGGGLVQPGGSLRLSCAASGFTFSSYNMNWVRQAPGKGLEWVSYISSSSSTI YYADSVKGRFTISRDNAKNSLSLQMNSLRDEDTAVYYCARAYYYGMDVWGQGTTVTVS S In one embodiment, the antibody portion used in the ADC of the present disclosure comprises all 6 CDR sequences of Enfortumab. In another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain variable region sequence and the light chain variable region sequence of Enfortumab. In yet another embodiment, the antibody portion used in the ADC of the present disclosure comprises the heavy chain sequence and the light chain sequence of Enfortumab. In some embodiments, the Ab unit of the ADC of the present disclosure comprises the three CDRs of the heavy chain variable region (VH) sequence of SEQ ID NO: 76 and the three CDRs of the light chain variable region (VL) sequence of SEQ ID NO: 75, and preferably, wherein the CDRs are defined according to Kabat or IMGT or a combination thereof. In some embodiments, the Ab unit of the ADC of the present disclosure comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: According to Kabat definition, HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 72, HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 73, HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 74, LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 69, LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 70, and LCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 71. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region, wherein the heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 76, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In one embodiment, the Ab unit of the ADC of the present disclosure comprises a light chain variable region, wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 75, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 76, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 75. In some embodiments, the Ab unit of the ADC of the present disclosure preferably further comprises an antibody heavy chain constant region and / or light chain constant region. Preferably, the heavy chain constant region is a heavy chain constant region derived from a human immunoglobulin. Preferably, the light chain constant region is a light chain constant region derived from a human immunoglobulin. In some aspects, the heavy chain constant region comprised in the Ab unit can be of any isotype or subtype, e.g., an IgG1, IgG2, IgG3, or IgG4 isotype heavy chain constant region, and preferably an IgG1, IgG2, or IgG4 heavy chain constant region, especially a human IgG1 heavy chain constant region. In further aspects, the light chain constant region comprised in the Ab unit can be a k light chain constant region or a X light chain constant region, especially a human k light chain constant region. In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human IgG1 heavy chain constant region. Preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 23, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 23, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 23. In some embodiments, the Ab unit of the ADC of the present disclosure comprises a human k light chain constant region. Preferably, the light chain constant region comprises the amino acid sequence of SEQ ID NO: 12, or an amino acid sequence comprising at least one, two, or three, but not more than 20, 10, or 5 amino acid changes relative to the amino acid sequence of SEQ ID NO: 12, or a sequence having at least 95-99% identity to the amino acid sequence of SEQ ID NO: 12. In some embodiments, the Ab unit of the ADC of the present disclosure is a full-length antibody comprising a heavy chain constant region and a light chain constant region. In some embodiments, the Ab unit is a tetrameric structure formed by two light chains and two heavy chains. In further embodiments, the Ab unit is an IgG antibody, especially an IgG1 antibody. In some preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the heavy chain comprises the amino acid sequence shown in SEQ ID NO: 68, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or consists thereof. In other preferred embodiments, the Ab unit of the ADC of the present disclosure comprises a heavy chain and a light chain, wherein: the light chain comprises the amino acid sequence shown in SEQ ID NO: 67, or an amino acid sequence having at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. In some more preferred embodiments, the Ab unit of the ADC of the present disclosure comprises: (a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 68, and (b) a light chain comprising the amino acid sequence of SEQ ID NO: 67. Cancers that can be treated with the Nectin-4-targeting ADCs of the present disclosure are Nectin4-positive cancers, including but not limited to breast cancer, cervical cancer, ovarian cancer, gastric cancer, esophageal cancer, head and neck cancer, lung cancer, non-small cell lung cancer, melanoma, bladder cancer, thyroid cancer, as well as hepatocellular carcinoma and urothelial carcinoma. Drug P Unit The drug P unit of the antibody-drug conjugate is also referred to herein as the payload of the ADC drug. In some embodiments, the drug P unit useful in the ADCs of the present disclosure is a KRas mutant inhibitor, including but not limited to inhibitors of G12C mutant, G12D mutant, G12V mutant, G12A mutant, G12R mutant, G12S mutant, and G13D mutant. In some embodiments, the drug P unit useful in the ADCs of the present disclosure is a KRas mutant inhibitor described in the applicant's previously filed PCT application PCT / CN2023 / 122129, more specifically the KRas mutant inhibitors defined below. In other embodiments, the drug P unit useful in the ADCs of the present disclosure is a pan-Ras inhibitor, which is capable of inhibiting almost all Ras isoforms regardless of mutation status, such as some of the drug P units exemplified or illustrated below, including but not limited to P8, P9, P12, P13, P16-23, P25-37, etc. Embodiment 1: The drug P unit useful in the ADCs of the present disclosure is specifically a compound of formula (I), a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, Rb Rc Ra 'n' (I) wherein: M is selected from N or C-Ri; M' is selected from N or C-R1'; Ri and Ri' are each independently selected from H, halogen, CN, -C1-6 alkyl optionally substituted by halogen, and -OC1-6 alkyl optionally substituted by halogen; Ra is selected from H, halogen, CN, -C1-6 alkyl optionally substituted by halogen, -C2-6 alkynyl optionally substituted by halogen, and -OC1-6 alkyl optionally substituted by halogen or deuterium; Rb and Rc together with the N atom to which they are attached form I        , wherein X is selected from CH2, N, and O; R2 and R2' are each independently selected from H, OH, or -C1-6 alkyl optionally substituted by halogen; or R2 and R2' attached to non-adjacent ring carbon atoms together form an intra-ring bridge -(CH2)i-2- or -CH2=CH2-; or R2 and R2' attached to the same ring carbon atom together with the ring carbon atom to which they are attached form a 4-6 membered spirocycloalkyl or a 4-6 membered spiroheterocycloalkyl containing 1 or 2 heteroatoms selected from N and O; Ar is selected from       v R3 is selected from H, -NH2, -NHC1-6 alkyl, -N(Ci-6 alkyl)2, and -OC1-6 alkyl; R4 is selected from -CN, halogen, -NO2, -C2-6 alkynyl optionally substituted by halogen, and -C1-6 alkyl optionally substituted by halogen; R5 is selected from H, -CN, halogen, -NO2, and halogen-substituted -C1-6 alkyl; R6 is selected from H, halogen, CN, -C1-6 alkyl, and -C2-6 alkynyl, wherein the -C1-6 alkyl and -C2-6 alkynyl are each independently optionally substituted by halogen; R7, R7', R8, and R8‘ are each independently selected from H, halogen, CN, -NO2, and -C1-6 alkyl optionally substituted by halogen; V and W are each independently selected from H, halogen, -C1-6 alkyl, OH, and NH2; Z is selected from O, N, and CH2; --(C)1.3 I R10 R is R9 and R10 are each independently selected from H, deuterium, -C1-6 alkyl, and -(CH2)n-C3-6 cycloalkyl, wherein the -C1-6 alkyl and -C3-6 cycloalkyl are each independently optionally substituted by deuterium, halogen, or -O-C1-6 alkyl, or R9 and R10 attached to the same carbon atom together with the carbon atom to which they are attached form a C3-4 cycloalkyl; R11 is selected from H, -C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, and -(CH2)n-C3-6 cycloalkyl, wherein the C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, or C3-6 cycloalkyl are each independently optionally substituted by deuterium, halogen, CN, or -O-C1-6 alkyl; R12 is selected from H, halogen, -CN, -OH, -NH2, -NHC1-6 alkyl, -N(Ci-6 alkyl)2, -O-C1-6 alkyl, -O-C3-6 cycloalkyl, -C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, -(CH2)n-C3-6 cycloalkyl, and =C(Rd)2, wherein Rd is each independently selected from H, halogen, and -C1-6 alkyl optionally substituted by halogen, wherein each occurrence of C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, or C3-6 cycloalkyl is each independently optionally substituted by halogen, CN, or -OC1-6 alkyl; R13 is selected from H, -C1-6 alkyl, and -(CH2)n-C3-6 cycloalkyl, wherein the -C1-6 alkyl and -C3-6 cycloalkyl are each independently optionally substituted by halogen or -O-C1-6 alkyl; k is selected from 0 or 1; m is selected from 0 to 6; and n is selected from 0 to 2; Thus, formula (I) can be specifically represented as: (Rl2)m Embodiment 1.1: The compound of formula (I) according to Embodiment 1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein M is C-R1. Embodiment 1.1.1: The compound of formula (I) according to Embodiment 1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri is H. Embodiment 1.1.2: The compound of formula (I) according to Embodiment 1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri is halogen, e.g., F, Cl. Embodiment 1.1.3: The compound of formula (I) according to Embodiment 1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri is CN. Embodiment 1.1.4: The compound of formula (I) according to Embodiment 1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R1 is -C1-6 alkyl optionally substituted by halogen, preferably -C1-3 alkyl optionally substituted by halogen, more preferably -C1-3 alkyl substituted by 1-3 halogens, most preferably -C1-3 alkyl substituted by 13 F, e.g., -CF3; examples of R1 include, but are not limited to -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2Cl, -CH2F, -CHF2, -CF3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5. Embodiment 1.1.5: The compound of formula (I) according to Embodiment 1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri is -OC1-6 alkyl optionally substituted by halogen, preferably -OC1-3 alkyl optionally substituted by halogen, e.g., -OC1-3 alkyl, such as -OCH3, -OCH2CH3. Embodiment 1.1.6: The compound of formula (I) according to Embodiment 1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri is selected from halogen and -C1-6 alkyl optionally substituted by halogen, preferably halogen and -C1-3 alkyl substituted by halogen, e.g., F, Cl, and -CF3. Embodiment 1.1.7: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is H. Embodiment 1.1.8: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is CN or halogen, e.g., F, Cl. Embodiment 1.1.9: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is -C1-6 alkyl optionally substituted by halogen, as generally or specifically defined in Embodiment 1.1.4. Embodiment 1.1.10: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is -C2-6 alkynyl optionally substituted by halogen, preferably -C2-4 alkynyl I|l £ optionally substituted by halogen, more preferably -C2-4 alkynyl, e.g., but not limited to, ■  ,   ।  . Embodiment 1.1.11: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is -OC1-6 alkyl optionally substituted by halogen or deuterium, preferably -OC1-3 alkyl optionally substituted by halogen or deuterium, more preferably -OC1-3 alkyl optionally substituted by deuterium, e.g., -OCH3, -OCD3, -OCH2CH3, most preferably -OCH3. Embodiment 1.1.12: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.11, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein M' is N. Embodiment 1.1.13: The compound of formula (I) according to any one of Embodiments 1.1 to 1.1.11, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein M' is C-R1'. Embodiment 1.1.14: The compound of formula (I) according to Embodiment 1.1.13, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R1' is selected from halogen, e.g., F, Cl, preferably F. Embodiment 1.1.15: The compound of formula (I) according to Embodiment 1.1.13, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R1' is CN. Embodiment 1.1.16: The compound of formula (I) according to Embodiment 1.1.13, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R1' is selected from -C1-6 alkyl optionally substituted by halogen and -OC1-6 alkyl optionally substituted by halogen, each as generally or specifically defined in Embodiments 1.1.4 and 1.1.5. Embodiment 1.2: The compound of formula (I) according to Embodiment 1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein M is N. Embodiment 1.2.1: The compound of formula (I) according to Embodiment 1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is H. Embodiment 1.2.2: The compound of formula (I) according to Embodiment 1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is CN, or Ra is halogen, e.g., F, Cl. Embodiment 1.2.3: The compound of formula (I) according to Embodiment 1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is -C1-6 alkyl optionally substituted by halogen, as generally or specifically defined in Embodiment 1.1.4. Embodiment 1.2.4: The compound of formula (I) according to Embodiment 1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is -C2-6 alkynyl optionally substituted by halogen, preferably -C2-4 alkynyl optionally substituted by halogen, more preferably -C2-4 alkynyl, e.g., but not limited to, ।  ,   ■  . Embodiment 1.2.5: The compound of formula (I) according to Embodiment 1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ra is -OC1-6 alkyl optionally substituted by halogen or deuterium, preferably -OC1-3 alkyl optionally substituted by halogen or deuterium, more preferably -OC1-3 alkyl optionally substituted by deuterium, e.g., -OCH3, -OCD3, -OCH2CH3, most preferably -OCH3. Embodiment 1.2.6: The compound of formula (I) according to any one of Embodiments 1.2 to 1.2.5, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein M' is N. Embodiment 1.2.7: The compound of formula (I) according to any one of Embodiments 1.2 to 1.2.5, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein M' is C-R1'. Embodiment 1.2.8: The compound of formula (I) according to Embodiment 1.2.7, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri' is selected from halogen, e.g., F, Cl, preferably F. Embodiment 1.2.9: The compound of formula (I) according to Embodiment 1.2.7, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri' is CN. Embodiment 1.2.10: The compound of formula (I) according to Embodiment 1.2.7, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ri' is selected from -C1-6 alkyl optionally substituted by halogen and -OC1-6 alkyl optionally substituted by halogen, each as generally or specifically defined in Embodiments 1.1.4 and 1.1.5. Embodiment 1.3: The compound of formula (I) according to Embodiment 1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein the structural fragment Ra , e.g., is Rl           or      Rl          . Specifically, M is C-R1, wherein Ri is selected from halogen (preferably F or Cl) or -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl substituted by halogen, more preferably -CF3), Ra is H, and M' is C-R1' and Ri' is halogen, preferably F; or M is N, Ra is selected from H, -C2-6 alkynyl (preferably -C2-4 alkynyl, more preferably -C=CH), and -OC1-6 alkyl (preferably -OC1-3 alkyl optionally substituted by deuterium, more preferably - OCH3, -OCD3, -OCH2CH3), and M' is C-R1' and Ri' is halogen, preferably F; Specific examples include, but are not limited to: Embodiment 2.1: The compound of formula (I) according to any one of Embodiments 1 to 1.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ar is       v Embodiment 2.1.1: The compound of formula (I) according to Embodiment 2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R3 is H; or R3 is selected from -NH2, -NHC1-6 alkyl, and N(C1-6 alkyl)2, preferably selected from -NH2, -NHC1-3 alkyl, and N(C1-3 alkyl)2, most preferably -NH2. Embodiment 2.1.2: The compound of formula (I) according to Embodiment 2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R3 is -OC1-6 alkyl, preferably -OC1-3 alkyl, e.g., -OCH3, -OCH2CH3. Embodiment 2.1.3: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R4 is CN. Embodiment 2.1.4: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R4 is halogen, selected from F, Cl, Br, I; or R4 is NO2. Embodiment 2.1.5: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R4 is -C2-6 alkynyl optionally substituted by halogen, preferably -C2-4 alkynyl optionally substituted by halogen, e.g., but not limited to, ■  ,   ■  . Embodiment 2.1.6: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R4 is -C1-6 alkyl optionally substituted by halogen, preferably -C1-3 alkyl optionally substituted by halogen, e.g., but not limited to, -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2Cl, -CH2F, -CHF2, -CF3, -CCl3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5. Embodiment 2.1.7: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R7 and R7' are each H; or R7 and R7' are each halogen, preferably F. Embodiment 2.1.8: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein one of R7 and R7' is H, and the other is selected from halogen, CN, and NO2, wherein the halogen is preferably F; e.g., R7 is H and R7' is halogen, preferably F, or R7' is H and R7 is halogen, preferably F. Embodiment 2.1.9: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein one of R7 and R7' is H, and the other is selected from -C1-6 alkyl optionally substituted by halogen, preferably -C1-3 alkyl optionally substituted by halogen, e.g., but not limited to, -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2Cl, -CH2F, -CHF2, -CF3, -CCl3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5. Embodiment 2.1.10: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.6, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein one of R7 and R7' is selected from halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen, wherein the -C1-6 alkyl optionally substituted by halogen is preferably -C1-3 alkyl optionally substituted by halogen, as specifically exemplified in Embodiment 2.1.9. Embodiment 2.1.11: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.10, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein V is H. Embodiment 2.1.12: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.10, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein V is -OH, or V is -NH2. Embodiment 2.1.13: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.10, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein V is halogen; or V is -C1-6 alkyl, preferably -C1-3 alkyl. Embodiment 2.1.14: The compound of formula (I) according to Embodiment 2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Ar is      OH , wherein R3 is H or halogen, R4 is selected from halogen, -C2-6 alkynyl OH (preferably -C2-4 alkynyl), and -C1-6 alkyl (preferably -C1-3 alkyl), e.g., but not limited to, OH , OH , OH , OH and OH Embodiment 2.1.15: The compound of formula (I) according to Embodiment 2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, R3 R4 wherein Ar is       v      , wherein R3 is selected from -NH2, -NHC1-6 alkyl, and N(Ci-6 alkyl)2, 10 preferably selected from -NH2, -NHC1-3 alkyl, and N(Ci-3 alkyl)2, most preferably -NH2; R4 is selected from -CN, halogen, -NO2, and -C2-6 alkynyl substituted by halogen; V is selected from H, -C1-6 alkyl (preferably -C1-3 alkyl), and halogen; R7 and R7' are each H, or each are halogen, or one of them is H and the other is halogen or halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), or one is halogen and the other is halogen-substituted C1-6 alkyl (preferably halogen-substituted -Ci-15   3 alkyl), wherein the halogen is preferably F; H2N CN 1 j r7'y'r7' Preferably, Ar is        v      , V is H, R7 and R7' are each H, or one of them is H and the other is halogen, wherein the halogen is preferably F; For example, but not limited to: Embodiment 2.1.16: The compound of formula (I) according to any one of Embodiments 2.1 to 2.1.15, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein the asterisk in       v can have axial chirality as appropriate (e.g., depending on the values of Ri and Ri'), including       v                   or V Embodiment 2.2: The compound of formula (I) according to any one of Embodiments 1 to 1.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, 10 wherein Ar is     w Embodiment 2.2.1: The compound of formula (I) according to Embodiment 2.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R5 is H; or R5 is halogen, selected from F, Cl, Br, I; preferably R5 is halogen, most preferably F; or R5 is NO2; or R5 is halogen-substituted -C1-3 alkyl. Embodiment 2.2.2: The compound of formula (I) according to Embodiment 2.2 or 2.2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R6 is H; or R6 is halogen, selected from F, Cl, Br, I. Embodiment 2.2.3: The compound of formula (I) according to Embodiment 2.2 or 2.2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R6 is -C1-6 alkyl optionally substituted by halogen, preferably -C1-3 alkyl optionally substituted by halogen, more preferably -C1-3 alkyl, e.g., but not limited to, -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2Cl, -CH2F, -CHF2, -CF3, -CCl3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5. Embodiment 2.2.4: The compound of formula (I) according to Embodiment 2.2 or 2.2.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R6 is -C2-6 alkynyl optionally substituted by halogen, preferably -C2-4 alkynyl optionally 1 IL substituted by halogen, more preferably -C2-4 alkynyl, e.g., but not limited to,      ,   ■  , preferably Embodiment 2.2.5: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R8 and R8' are each H; or R8 and R8' are each halogen, preferably F. Embodiment 2.2.6: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein one of R8 and R8' is H, and the other is selected from halogen, CN, and NO2, wherein the halogen is preferably F. Embodiment 2.2.7: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein one of R8 and R8' is H, and the other is selected from -C1-6 alkyl optionally substituted by halogen, preferably -C1-3 alkyl optionally substituted by halogen, as generally or specifically defined in Embodiment 2.1.9. Embodiment 2.2.8: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein one of R8 and R8' is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen, wherein the -C1-6 alkyl optionally substituted by halogen is preferably -C1-3 alkyl optionally substituted by halogen, as generally or specifically defined in Embodiment 2.1.9. Embodiment 2.2.9: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.8, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein W is -OH. Embodiment 2.2.10: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.8, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein W is -NH2. Embodiment 2.2.11: The compound of formula (I) according to Embodiment 2.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, R5 R6 wherein Ar is r8’ 0H , wherein R5 is H or halogen, R6 is selected from halogen, -C2-6 alkynyl, 10 and -C1-6 alkyl; Rs and Rs' are each H; or Rs and Rs' are each halogen; or one of Rs and Rs' is H and the other is selected from halogen, CN, and NO2; or one of Rs and Rs' is H and the other is selected from -C1-6 alkyl optionally substituted by halogen; or one of Rs and Rs' is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen; , wherein R5 is halogen, preferably F, R6 is selected from -C2-6 alkynyl (preferably -C2-4 alkynyl), Embodiment 2.2.12: The compound of formula (I) according to any one of Embodiments 2.2 to 2.2.11, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or R. solvate thereof, wherein * in     w the Definitions section. can have axial chirality as appropriate, as exemplified in Embodiment 3.1: The compound of formula (I) according to any one of Embodiments 1 to 2.2.12, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein in      I        formed by Rb and Rc together with the N atom to which they are attached, k is 0 and X is selected from CH2, N, and O, i.e., Rb and Rc together with the N atom to which they are attached form x / X / W                       sZWV ।             or           1           ; or k is 1 and X is selected from CH2, N, and O, i.e., Rb and Rc together with the N atom to which . 1                   . .     1     1                         jwv                            -jx / x / xr they are attached form       ■       ,        ।        or Embodiment 3.1.1: The compound of formula (I) according to Embodiment 3.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Rb and ^R2'     R2'\' J~R2' Rc together with the N atom to which they are attached form       1        or               , wherein R2 and R2' are each independently selected from H, OH, and -C1-6 alkyl optionally substituted by halogen, preferably OH and -C1-6 alkyl optionally substituted by halogen, more preferably selected from OH and -C1-3 alkyl; or R2 and R2' attached to the same ring carbon atom together with the ring carbon atom to which they are attached form a 4-6 membered spirocycloalkyl or a 4-6 membered spiroheterocycloalkyl containing 1 or 2 heteroatoms selected from N and O. Embodiment 3.1.1.1: The compound of formula (I) according to Embodiment 3.1.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R2 and R2' can each independently be attached to any ring carbon atom, preferably R2\ R2 k / N— R2 r2' , more preferably and , e.g., Further, one of R2 and R2' is -OH and the other is -C1-6 alkyl, preferably -C1-3 alkyl, more preferably methyl; or R2 and R2' together with the ring carbon atom to which they are attached form a 4-6 membered spirocycloalkyl or a 4-6 membered spiroheterocycloalkyl containing 1 or 2 heteroatoms selected from N and O; Further, where chemically feasible, substituents R2 and R2' can each be in stereoisomeric form, e.g., R or S configuration; Specific examples include, but are not limited to: Embodiment 3.1.2: The compound of formula (I) according to Embodiment 3.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Rb and Rc together with the N atom to which they are attached form      ।      , wherein R2 and R2', attached to non-adjacent ring carbon atoms together form an intra-ring bridge -CH2-, -CH2CH2-, or -CH2=CH2-; HHHHHHHHH Specific examples include     , preferably Embodiment 4.1: The compound of formula (I) according to any one of Embodiments 1 to 3.1.2, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein Z is O; or Z is N; or Z is CH2; preferably Z is O. Embodiment 5.1: The compound of formula (I) according to any one of Embodiments 1 to 4.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R is Embodiment 5.1.1: The compound of formula (I) according to any one of Embodiments 1 to 5.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R9 and R10 are both H; or one or both are deuterium. Embodiment 5.1.1.1: The compound of formula (I) according to any one of Embodiments 1 to 5.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R9 and R10 are each independently selected from H and -C1-6 alkyl, preferably -C1-3 alkyl, optionally substituted by deuterium, halogen, or -OC1-6 alkyl, e.g., one of them is H and the other is the defined alkyl, or both are the defined alkyl; examples of such alkyl include, but are not limited to, -CH3, -CD3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2-OCH3, -CH2-O-CH2CH3, -CH2CH2-O-CH3, -CH2CH2-O-CH2CH3, -CH2F, -CH2Cl, -CHF2, -CF3, -CCl3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3. Embodiment 5.1.1.2: The compound of formula (I) according to any one of Embodiments 1 to 5.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R9 and R10 are each independently selected from H and -(CH2)n-C3-6 cycloalkyl (preferably -C3-6 cycloalkyl), wherein the C3-6 cycloalkyl is optionally substituted by halogen or C1-6 alkoxy, e.g., one of them is H and the other is the defined cycloalkyl; examples include, but are not limited to, Embodiment 5.1.1.3: The compound of formula (I) according to any one of Embodiments 1 to 5.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R9 and R10 attached to the same carbon atom together with the carbon atom to which they are attached form a C3-4 cycloalkyl, e.g., cyclopropyl, cyclobutyl. Embodiment 5.1.2: The compound of formula (I) according to any one of Embodiments 1 to 5.1.1.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R11 is H. Embodiment 5.1.2.1: The compound of formula (I) according to any one of Embodiments 1 to 5.1.1.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R11 is -C1-6 alkyl, preferably -C1.3 alkyl, optionally substituted by deuterium, halogen, CN, or -C1-6 alkoxy, preferably optionally substituted by deuterium, halogen, or -C1-3 alkoxy; examples include, but are not limited to, -CH3, -CD3, -CH2CH3, -CH2CD3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2-OCH3, -CH2-O-CH2CH3, -CH2CH2-O-CH3, -CH2CH2-O-CH2CH3, -CH(CH3)CH2-OCH3, -CH2CH(CH3)-OCH3, -CH2F, - CH2Q, -CHF2, -CF3, -CH2CH2F, -CH2CHF2, -CH(CH3)F, -CH(CH3)CH2F, -CH2CH(CH3)F, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5, -CH2CN, -CH2CH2CN; More preferably, R11 is -C1-3 alkyl, wherein the hydrogen atom is optionally replaced by one or more isotope deuterium, e.g., -CH3, -CD3. Embodiment 5.1.2.2: The compound of formula (I) according to any one of Embodiments 1 to 5.1.1.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R11 is -C2-6 alkenyl or -C2-6 alkynyl, preferably -C2-4 alkenyl or -C2-4 alkynyl, optionally substituted by halogen, CN, or -C1-6 alkoxy; examples include, but are not limited to, ethenyl, propenyl, ethynyl, each optionally substituted by halogen or -C1-6 alkoxy. Embodiment 5.1.2.3: The compound of formula (I) according to any one of Embodiments 1 to 5.1.1.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R11 is -(CH2)n-C3-6 cycloalkyl, preferably -C3-6 cycloalkyl, wherein the -C3-6 cycloalkyl is optionally substituted by deuterium, halogen, CN, or -C1-6 alkoxy; examples include, but are not limited to Embodiment 5.1.3: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is H. Embodiment 5.1.3.1: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is halogen, e.g., F, Cl, Br, I, preferably F; or R12 is CN. Embodiment 5.1.3.2: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is -NH2, -NHC1-6 alkyl, -N(Ci-6 alkyl)2, wherein the -C1-6 alkyl is preferably -Ci-3 alkyl, optionally substituted by halogen, CN, or -OCi-6 alkyl. Embodiment 5.1.3.3: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is -OH; or R12 is -O-Ci-6 alkyl, preferably -O-C1-3 alkyl, wherein the alkyl is optionally substituted by halogen, CN, or -OCi-6 alkyl; examples include, but are not limited to, -O-CH3, -O-CH2CH3, -O-CH2CH2CH3, -O-CH(CH3)(CH3), -O-CH2CH2CH2CH3, -O-CH2CH(CH3)CH3, -O-C(CH3)3, -O-CH2Cl, -O-CH2CN, -O-CH2F, -O-CHF2, -O-CF3, -O-CCl3, -O-CH2CH2F, -o-CH2CH2CN, -O-CH2CHF2, -O-CH2CF3, -O-CH2CH2CH2F, -O-CH2CH2CHF2, -O-CH2CH2CF3, -o-C(CH3)2CF3, -O-C2F5, -O-CH2-OCH3, -O-CH2-O-CH2CH3, -O-CH2CH2-O-CH3, -O-CH2CH2-O-CH2CH3. Embodiment 5.1.3.4: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is -Ci-6 alkyl, preferably -C1-3 alkyl, optionally substituted by halogen, CN, or -OC1-6 alkyl, e.g., but not limited to, -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), - CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2-OCH3, -CH2-O-CH2CH3, -CH2CH2-O-CH3, -CH2CH2-O-CH2CH3, -CH(CH3)CH2-OCH3, -CH2CH(CH3)-OCH3, -CH2F, -CH2Cl, -CHF2, -CF3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5, -CH2CN, -CH2CH2CN. Embodiment 5.1.3.5: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is -O-C3-6 cycloalkyl, wherein the C3-6 cycloalkyl is optionally substituted by halogen, CN, or -O-Ci-6 alkyl; examples include, but are not limited to, ^^^,   0         , Embodiment 5.1.3.6: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is -(CH2)n-C3-6 cycloalkyl, preferably -C3-6 cycloalkyl, wherein the -C3-6 cycloalkyl is optionally substituted by halogen, CN, or -C1-6 alkoxy; as exemplified in Embodiment 5.1.2.3. Embodiment 5.1.3.7: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is -C2-6 alkenyl or -C2-6 alkynyl, preferably -C2-4 alkenyl or -C2-4 alkynyl, optionally substituted by halogen, CN, or -C1-6 alkoxy; examples include, but are not limited to, ethenyl, propenyl, ethynyl, each optionally substituted by halogen or -C1-6 alkoxy. Embodiment 5.1.3.8: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is =C(Rd)2, wherein Rd is each independently selected from H, F, Cl, Br, I, -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl); examples include, but are not limited to, =CH2, =CF2, =CHF, =CCl2, =C(CH3)2, =C(CF3)2. Embodiment 5.1.3.9: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F). Embodiment 5.1.3.10: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein m is 0, 1, or 2, preferably 1. Embodiment 5.1.3.11: The compound of formula (I) according to any one of Embodiments 1 to 5.1.2.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein the ring carbon atom to which R12 is attached can be chiral, having R configuration or S configuration. Embodiment 5.1.3.12: The compound of formula (I) according to any one of Embodiments 5.1.3.8 to 5.1.3.9, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein when R12 is =C(Rd)2, the double bond can have geometric isomers, including E and Z forms, preferably E isomer. Embodiment 5.1.4: The compound of formula (I) according to any one of Embodiments 1 to 5.1.3.12, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R13 is H. Embodiment 5.1.4.1: The compound of formula (I) according to any one of Embodiments 1 to 5.1.3.12, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R13 is halogen, preferably F. Embodiment 5.1.4.2: The compound of formula (I) according to any one of Embodiments 1 to 5.1.3.12, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R13 is -C1-6 alkyl, preferably -C1-3 alkyl, optionally substituted by halogen or -OC1-6 alkyl, e.g., but not limited to, -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)(CH3), -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -C(CH3)3, -CH2-OCH3, -CH2-O-CH2CH3, -CH2CH2-O-CH3, -CH2CH2-O- CH2CH3, -CH(CH3)CH2-OCH3, -CH2CH(CH3)-OCH3, -CH2F, -CHiCl, -CHF2, -CF3, -CH2CH2F, -CH2CHF2, -CH2CF3, -CH2CH2CH2F, -CH2CH2CHF2, -CH2CH2CF3, -C2F5. Embodiment 5.1.4.3: The compound of formula (I) according to any one of Embodiments 1 to 5.1.3.12, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R13 is -(CH2)n-C3-6 cycloalkyl, wherein the C3-6 cycloalkyl is optionally substituted by halogen or -OC1-6 alkyl; examples include, but are not limited Embodiment 5.1.4.4.: The compound of formula (I) according to any one of Embodiments 1 to 5.1.3.12, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R13 is -C1-6 alkyl, preferably -C1-3 alkyl, more preferably -CH3. Embodiment 5.2: The compound of formula (I) according to any one of Embodiments 1 to 5.1.4.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate , more preferably          Rl1 wherein R9 and R10 are both H, or one or both are deuterium; R11 is -C1-3 alkyl, wherein the hydrogen atom is optionally replaced by one or more isotope deuterium; R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F); R13 is -C1-6 alkyl (preferably -C1-3 alkyl); m is 1 or 2; Specifically, R is        Rl1         , wherein R11, R12, and m have the meanings defined, examples of R11 include, but are not limited to, methyl, ethyl, isopropyl, -CD3, -CH2CD3; and / or examples of R12 include, but are not limited to, fluoromethyl, difluoromethyl, methyl, fluoro methylene, difluoro methylene, methylene. Embodiment 5.3: The compound of formula (I) according to any one of Embodiments 1 to 5.1.4.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein R is         Ru , preferably         Rl1 , wherein R9 and R10 are both H, or one or both are deuterium; R11 is -C1-3 alkyl, wherein the hydrogen atom is optionally replaced by one or more isotope deuterium; R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F); R13 is -C1-6 alkyl (preferably -C1-3 alkyl); m is 1 or 2; (R12)m Specifically, R is        Rl1 , wherein R11, R12, and m have the meanings defined, examples of R11 include, but are not limited to, methyl, ethyl, isopropyl, -CD3, -CH2CD3; and / or examples of R12 include, but are not limited to, fluoromethyl, difluoromethyl, methyl, fluoro methylene, difluoro methylene, methylene. Embodiment 5.4: The compound of formula (I) according to any one of Embodiments 1 to 5.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein examples of R include, but are not limited to ^ < < ':>S I              \          CD3          cd3           |          | ,,,,  , Preferably Embodiment 6.1: The compound of formula (I) according to Embodiment 1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, having a subgeneral formula as shown in Table 1 below: (I-A-1'') (I-B-1'') (I-A-2) H (I-A-2') (I-B-2) H (I-A-2'') (I-B-2') H (I-B-2'') wherein each substituent has the meaning as generally or specifically defined in the respective corresponding embodiments above, and also encompasses any combination of the generally or specifically defined meanings of each substituent; Preferably, wherein when M is C-Ri, Ri is selected from halogen (preferably F or Cl) or -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl substituted by halogen, more preferably -CF3), Ra is H, and M' is C-Ri' and Ri' is halogen (preferably F); when M is N, Ra is selected from H, -C2-6 alkynyl (preferably -C2-4 alkynyl, more preferably -C=CH), and -OC1-6 alkyl (preferably -OC1-3 alkyl optionally substituted by deuterium, more preferably -OCH3, -OCD3, -OCH2CH3), and M' is C-R1' and R1' is halogen (preferably F); R2 and R2' attached to non-adjacent ring carbon atoms together form an intra-ring bridge -(CH2)1-2- or -CH2=CH2-; R3 is selected from -NH2, -NHC1-6 alkyl, and N(C1-6 alkyl)2 (preferably selected from -NH2, -NHC1-3 alkyl, and N(C1-3 alkyl)2, more preferably -NH2); R4 is selected from -CN, halogen, -NO2, and -C2-6 alkynyl substituted by halogen; V is selected from H, -C1-6 alkyl (preferably -C1-3 alkyl), and halogen; R7 and R7' are each H, or each are halogen, or one of them is H and the other is halogen or halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), or one is halogen and the other is halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), wherein the halogen is preferably F; Preferably, R3 is -NH2, R4 is -CN, V is H, R7 and R7' are each H, or one of them is H and the other is halogen (preferably F); R5 is H or halogen (preferably F); R6 is selected from halogen, -C2-6 alkynyl (preferably -C2-4 alkynyl), and -C1-6 alkyl (preferably -C1-3 alkyl); R8 and R8' are each H, or R8 and R8' are each halogen, or one of R8 and R8' is H and the other is selected from halogen, CN, and NO2, or one of R8 and R8' is H and the other is selected from -C1-6 alkyl optionally substituted by halogen, or one of R8 and R8' is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen; W is OH; Preferably, R5 is halogen (preferably F), R6 is selected from -C2-6 alkynyl (preferably -C2-4 alkynyl), R8 and R8' are each H, W is OH; Z is selected from O, N, and CH2; R9 and R10 are both H; or one or both are deuterium; R11 is -C1-6 alkyl (preferably -C1-3 alkyl), wherein the hydrogen atom is optionally replaced by one or more isotope deuterium; R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F); m is 0, 1, or 2 (preferably 1 or 2); R13 is -C1-6 alkyl (preferably -C1-3 alkyl, more preferably -CH3). Embodiment 6.2: The compound of formula (I) according to Embodiment 1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, having a subgeneral formula as shown in Table 2 below: (I-C) (I-D) (I-C-1) (I-D-1) (I-C-1') (I-D-1') (I-C-1'') (I-D-1'') wherein each substituent has the meaning as generally or specifically defined in the respective corresponding embodiments above, and also encompasses any combination of the generally or specifically defined meanings of each substituent; Preferably, wherein 5        when M is C-Ri, Ri is selected from halogen (preferably F or Cl) or -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl substituted by halogen, more preferably -CF3), Ra is H, and M' is C-Ri' and Ri' is halogen (preferably F); when M is N, Ra is selected from H, -C2-6 alkynyl (preferably -C2-4 alkynyl, more preferably -C=CH), and -OC1-6 alkyl (preferably -OC1-3 alkyl optionally substituted by deuterium, more 10   preferably -OCH3, -OCD3, -OCH2CH3), and M' is C-R1' and R1' is halogen (preferably F); the structural fragment I is selected from and wherein X is selected from C, N, and O; one of R2 and R2' is -OH and the other is -C1-6 alkyl, or R2 and R2' together with the ring carbon atom to which they are attached form a 4-6 membered spirocycloalkyl or a 4-6 membered spiroheterocycloalkyl containing 1 or 2 heteroatoms selected from N and O; Preferably, JWV I      is selected from and wherein one of R2 and R2' is -OH and the other is -C1-3 alkyl, preferably methyl, more preferably             and R3 is selected from -NH2, -NHC1-6 alkyl, and N(C1-6 alkyl)2 (preferably selected from -NH2, -NHC1-3 alkyl, and N(Ci-3 alkyl)2, more preferably -NH2); R4 is selected from -CN, halogen, -NO2, and -C2-6 alkynyl substituted by halogen; V is selected from H, -C1-6 alkyl (preferably -C1-3 alkyl), and halogen; R7 and R7' are each H, or each are halogen, or one of them is H and the other is halogen or halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), or one is halogen and the other is halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), wherein the halogen is preferably F; Preferably, R3 is -NH2, R4 is -CN, V is H, R7 and R7' are each H, or one of them is H and the other is halogen (preferably F); R5 is H or halogen (preferably F); R6 is selected from halogen, -C2-6 alkynyl (preferably -C2-4 alkynyl), and -C1-6 alkyl (preferably -C1-3 alkyl); R8 and R8' are each H, or R8 and R8' are each halogen, or one of R8 and R8' is H and the other is selected from halogen, CN, and NO2, or one of R8 and R8' is H and the other is selected from -C1-6 alkyl optionally substituted by halogen, or one of R8 and R8' is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen; W is OH; Preferably, R5 is halogen (preferably F), R6 is selected from -C2-6 alkynyl (preferably -C2-4 alkynyl), R8 and R8' are each H, W is OH; Z is selected from O, N, and CH2; R9 and R10 are both H; or one or both are deuterium; R11 is -C1-6 alkyl (preferably -C1-3 alkyl), wherein the hydrogen atom is optionally replaced by one or more isotope deuterium; R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F); 5         m is 0, 1, or 2 (preferably 1 or 2); R13 is -C1-6 alkyl (preferably -C1-3 alkyl, more preferably -CH3). Embodiment 6.3: A compound of formula (I'), a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, having a sub-general formula as shown in Table 2-1 below: 10 (I'-A-1) (I'-B-1) (I'-C-1) wherein (I'-A-2) (I'-B-2) (I'-C-2) M, M', X, Z, V, W, R1, Ri', R3, R4, R5, R6, R7, R7', R8, R«', R9, R10, R11, R12, R13, k, m, n are respectively as defined above for each embodiment of the compound of formula (I); __ R4 %Xa- IX Ry'^f R7' the structural fragment       v       is as defined above in any one of Embodiments 2.1 to 2.1.16 for formula (I); R5 |¥6 O^¥ xx RIT Rs' the structural fragment     w       is as defined above in any one of Embodiments 2.2 to 2.2.12 for formula (I); the structural fragment         Rl1         is as defined above in any one of Embodiments 5.1 to 5.4 for formula (I); Y is selected from -CH2-, -CH2CH2-, -CH2OCH2-, or is absent; R14 and R15 are each independently selected from H and -C1-6 alkyl. Embodiment 6.3.1: The compound of formula (I') according to Embodiment 6.3, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein, 1                                । in the fragment     M' N ^, when M is C-R1, Ri is selected from halogen (preferably F or Cl) or -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl substituted by halogen, more preferably -CF3), and M' is C-R1' and Ri' is halogen (preferably F); or when M is N, M' is C-R1' and Ri' is halogen (preferably F); in the fragment       R3 , both M are C-R1, or one M is N and the other M is C-R1, Ri are each independently selected from H, halogen (preferably F), and halogen-substituted -C1-6 alkyl (preferably -C1-3 alkyl substituted by one or more F, more preferably -CF3), preferably the M ortho to R3 is selected from N and C-R1 (preferably C-halogen, more preferably C-F), and the M ortho to R6 is C-R1 (preferably C-halogen-substituted -C1-3 alkyl, more preferably -C-CF3); R3 is selected from -NH2, -NHC1-6 alkyl, and N(Ci-6 alkyl)2 (preferably selected from -NH2, -NHC1-3 alkyl, and N(Ci-3 alkyl)2, more preferably -NH2); R5 is H or halogen (preferably F); R6 is selected from halogen (preferably Cl) and -C1-6 alkyl (preferably -C1-3 alkyl); __ r4 Sx XI in the fragment       v       , R3 is selected from -NH2, -NHC1-6 alkyl, and N(Ci-6 alkyl)2 (preferably selected from -NH2, -NHC1-3 alkyl, and N(Ci-3 alkyl)2, more preferably -NH2); R4 is selected from -CN, halogen, -NO2, and -C2-6 alkynyl substituted by halogen; V is selected from H, -C1-6 alkyl (preferably -C1-3 alkyl), and halogen; R7 and R7' are each H, or each are halogen, or one of them is H and the other is halogen or halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), or one is halogen and the other is halogen-substituted C1-6 alkyl (preferably halogensubstituted -C1-3 alkyl), wherein the halogen is preferably F; Preferably, R3 is -NH2, R4 is -CN, V is H, R7 and R7' are each H, or one of them is H and the other is halogen (preferably F); R5 X?6 (X v XX rX*8' in the fragment     w      , R5 is H or halogen (preferably F); R6 is selected from halogen, - C2-6 alkynyl (preferably -C2-4 alkynyl), and -C1-6 alkyl (preferably -C1-3 alkyl); R8 and R8' are each H, or R8 and R8' are each halogen, or one of R8 and R8' is H and the other is selected from halogen, CN, and NO2, or one of R8 and R8' is H and the other is selected from -C1-6 alkyl optionally substituted by halogen, or one of R8 and R8' is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen; W is OH; Preferably, R5 is halogen (preferably F), R6 is selected from -C2-6 alkynyl (preferably -C2-4 alkynyl), R8 and R81 are each H, W is OH; X is selected from O and NH; Y is selected from -CH2CH2- and is absent; Z is selected from O; R9 and R10 are both H; or one or both are deuterium; R11 is -C1-6 alkyl (preferably -C1-3 alkyl), wherein the hydrogen atom is optionally replaced by one or more isotope deuterium; R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F); m is 0, 1, or 2 (preferably 1 or 2); n and k are 0 or 1 (preferably 0); R13 is -C1-6 alkyl (preferably -C1-3 alkyl, more preferably -CH3); 5        R14 and R15 are H or -C1-3 alkyl, more preferably -CH3. Embodiment 6.4: The compound according to any one of Embodiments 6.1 to 6.3.1, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, 10 . ?9 i-(C)i.3 i R10 wherein the R fragment Embodiment 6.5: The compound according to any one of Embodiments 6.1 to 6.4, a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein the Ar moiety, i.e., the left-side fragment, optionally has axial chirality, as shown below: OH OH , e.g., 15 Embodiment 7: A KRas mutant inhibitor compound selected from the following compounds, stereoisomers, tautomers, stable isotopic variants, pharmaceutically acceptable salts, or solvates thereof: or a pharmaceutically acceptable salt or solvate thereof. 10        It should be noted that the KRas mutant inhibitor compounds defined above, which are suitable for the ADCs of the present disclosure, are bonded to the linker unit L of the ADC via the ring NH present in the      i        moiety thereof, and / or via the OH present on the side-chain naphthalene or benzothiophene ring. Embodiment 8: A Ras mutant inhibitor compound selected from the following compounds, 15 stereoisomers, tautomers, stable isotopic variants, pharmaceutically acceptable salts, or solvates thereof: wherein each Ras mutant inhibitor compound is linked to the linker unit L of the ADC via the -NH2, -NH-, N, or -OH present in its structure; or selected from Ras inhibitor compounds disclosed in 5 the following patent publications, with representative compounds as follows: 10 Ras protein degraders V’     V V. °H                  X,N                            o=) N'V         NcX / S            NH WO2024120424                                            I                      ,.. / A            „ / v /    h P VZ"                  W 'n^W Xy    N                    WO2023099620         \= / Q /                        spN OH Ras molecular glue %■■ Ov0 o           pAT0 o           %• Oy0 c 1 "AV      A XV      r° H AJI -v x VH       “V V nA h       -v X Xs h nV z^W^             HAppV /          nV / /    ___ / / || T                                  / / Y___P || T                                   / / Y___ / / (I T )= / W              ')= / N-VV               ')= / \XX / — N       (                               r- N       (                                  / —N       ( Cj   '               Cj   ^3              Cj   v N—N—                              N— /           WO2022060836                    /           WO2024008834                     /          WO2024067857 %-Op 0         pCX0 0          %-Q 0 1 hXy         r° H A7X         r° HX ■°>- A nA h v    -p X x h v “X A AsH nx LA^Vy        nV kvH         nV VyT7 / / yxji j                 ( / —AT J                  <z yTT J )= / \VX            \= / W         ho )=* w X) x          / <        p / < N—7                         0 N—7                            0 N—7 /           WO2024169914             x__ /          WO2024153208                  \__ /          WO2024060966 %-Oy° O          °Y Oy0 0            Pi ?o H V.          r° TLX        pXp0 o >4X“ / ~  > / A"Y  0 ? / ¼ o^=f '          pTxT A         O         V k / \                       XX                       N—' x /                                                         y 5         1         WO2024104364                        F     CN117534687                <(          WO2022212894 O. X ,N. ,O                             0. ,L ,N._ ,O X' N      0   ।                    X' N X 0   ।                    p\, r° H AnXX         H XxX     °yCvo r- “xX Ax -v x~X nH v0 A Tn-VX oATT x TAAA^xA ~x A As H ° O      1 C     A T-xu N— /                          CF3 n—                                         ( /           WO2024008610          3 /           WO2024211712                        \ WO2021091082 CY . C^N^y-0            A .F                °X         0 v w4 >xA / I । i / S                                        NX / XXXV        <XXTY / —\ L J                          X=* N-xx )=7 nVX                            , O )A         o O— /               WO2024208934                      /                 WO2024249299 Tri / tetracyclic Ras inhibitors CN / ...Tk                      f i|i °z                              f i|i °z H2N CN.. °\ / N                 XY nTyAn       I3       XX nTyAn       I3      H N XTa Tx Vxx V'''-XWO2024041573 XJ              OH $02024032703                   °H WO20240178313                F' I                P            u '■'p              °X‘‘ An^'V3 o । X X" V ; - rXXP Y Ax A'0 xx ° / XZXpY \= / nXA A              WO2023172940 0                p\ %XN'n y°0 I r- 1 VAW N- /                        ~N / / Y XT V                \ \= / nXA A             WO2023086341 °yO y°o yyy I / vjxxy^ xA v A nV WxV'V '— / (z Hl J )= / nY / C ) CF’ N—' Xf                         WO2022217053 M°      xAVi? x Ypxx0.....> oAtqA"7 US20210130303 / ■■"O           i11 )" x f cn , ? Y       X nYn / Axx wH W F        \ /               WO2024009191 WO2024041573 '—             OH WO2024032704 WO2023046135 Small molecule Ras inhibitors OH WO2024012519 OH WO2022132200 HO OH OH WO2023061294 OH WO2024119277 O OH WO2024046370                       WO2023173016 OH WO2024040109 WO2022248885 WO2024044667 5 OH WO2023143312 OH WO2023098425 OH WO2023098426 OH WO2023030495 OH WO2022227987 NH2 ON 115490709 OH CN115385938 WO2022061251 WO2023246903 ' , , WV4U44 I 341 JU NH2 WO2022192794 WO2022232332                 OH WO2022262686 OH WO2022232331 OH WO2022193871 OH   CN117586280 OH WO2024131827 OH WO2022194191 WO2022177917 W02022221386 WO2023015559 OH WO2022194192 OH WO2022194192 OH WO2023101928 NH2 WO2022161443 OH CN 115368383 OH WO2022066646 OH CN115385937 H Other types of small molecule Ras inhibitors WO2022206723 WO2021215544 It should be noted that the Ras mutant inhibitor compounds of the present disclosure encompass each of the above independent embodiments or each specific embodiment, and also encompass embodiments constituted by any combination or sub-combination of the above various embodiments or specific embodiments, and also encompass embodiments constituted by any combination of any of the above preferred or exemplified embodiments. It should be noted that the present disclosure encompasses ADC compounds formed by any of the above general, specific, or preferred Ras mutant inhibitor compounds with the linker units and antibodies defined herein. Linker Unit L In the ADCs described herein, the Ras inhibitor, e.g., KRas mutant inhibitor, is linked to the antibody or antigen-binding fragment via a linker unit. The linker unit connects the Ras inhibitor, e.g., KRas mutant inhibitor, to the antibody or antigen-binding fragment by forming a covalent bond with the Ras inhibitor, e.g., KRas mutant inhibitor, at one position thereof and forming a covalent bond with the antibody or antigen-binding fragment at another position thereof. The linker units can be monovalent with respect to the Ras inhibitor, e.g., KRas mutant inhibitor, such that they covalently link a single Ras inhibitor, e.g., KRas mutant inhibitor, to a single site on the antibody or fragment thereof, or they can be multivalent with respect to the Ras inhibitor, e.g., KRas mutant inhibitor, such that they covalently link more than one Ras inhibitor, e.g., KRas mutant inhibitor, to a single site on the antibody or fragment thereof. As used herein, the expression "linker unit" is intended to include un-conjugated, partially conjugated (i.e., coupled only to the Ras inhibitor, e.g., KRas mutant inhibitor, or only to Ab), and fully conjugated forms (i.e., coupled to both the Ras inhibitor, e.g., KRas mutant inhibitor, and Ab) of the linker unit. The number of Ras inhibitors, e.g., KRas mutant inhibitors, linked to the antibody or antigenbinding fragment of the ADC can vary (referred to as "drug-to-antibody ratio" or "DAR") and will be limited by the number of available linking sites on the antibody or antigen-binding fragment and the number of Ras inhibitors, e.g., KRas mutant inhibitors, attached to a single linker. In ADCs comprising multiple Ras inhibitors, e.g., KRas mutant inhibitors, each Ras inhibitor, e.g., KRas mutant inhibitor, may be the same or different. ADCs with a DAR of 10 or even higher are contemplated as long as the ADC does not exhibit unacceptable levels of aggregation under conditions of use and / or storage. In some embodiments, the ADCs described herein can have a DAR in the range of about 1 to 10, 1 to 9, 1 to 8, 1 to 7, 1 to 6, 1 to 5, or 1 to 4. In some embodiments, the ADCs described herein can have a DAR in the range of about 2 to 10, 2 to 9, 2 to 8, 2 to 7, 2 to 6, 2 to 5, or 2 to 4. In certain specific embodiments, the ADC can have a DAR of about 1, 2, 3, or 4. In other specific embodiments, the ADC can have a DAR of about 5, 6, 7, or 8. In some specific embodiments, the ADC can have a DAR of about 1. The linker unit L suitable for the ADC of the present disclosure can be any linker capable of coupling the drug of the present disclosure to the antibody. Suitably, the incorporation of the linker should ensure sufficient stability of the ADC of the present disclosure in the circulatory system, should not be cleaved prematurely in the circulation to trigger off-target toxicity, while allowing for rapid and effective release of the KRas mutant inhibitor at the target site (e.g., tumor cells or tumor environment). For example, the linker unit can be chemically stable to the extracellular environment and serum, or can include intentionally labile linker units and can release the Ras inhibitor, e.g., KRas mutant inhibitor, in the extracellular environment or tumor microenvironment. In some embodiments, the linker unit includes a bond designed to release the Ras inhibitor, e.g., KRas mutant inhibitor, after intracellular internalization of the ADC. In some specific embodiments, the linker unit includes a bond designed to be cleaved and / or digested intracellularly or otherwise specifically or non-specifically degraded. In some embodiments, the linker unit in the ADC of formula (X) of the present disclosure is a non-degradable linker. Examples of non-degradable linker units include, but are not limited to, thioether linkers, N-succinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC), and maleimidocaproyl (MC). Generally, such linkers are more stable, and ADCs containing such linkers must be internalized by cells, where intracellular lysosomal proteases degrade the antibody portion of the ADC to release the active drug molecule. In further embodiments, the linker unit in the ADC of formula (X) of the present disclosure is a degradable linker unit, which contains one or more chemically or enzymatically cleavable chemical bonds. Drug release from ADCs containing such linkers is triggered by the nature of the cleavage site in the linker. Therefore, the cleavage site of such linkers can be designed according to the characteristics of the target therapeutic site (e.g., tumor cell lysosomes and / or tumor environment). In some embodiments, the degradable linker unit contains a chemically labile group that exploits the differential properties between plasma and some cytoplasmic compartments, such as the acidic environment of endosomes or lysosomes or the high thiol concentration in the cytosol (e.g., glutathione); in some cases, the plasma stability of linkers containing chemically labile groups can be increased or decreased by using substituents to alter the steric hindrance around the group. In some embodiments, the chemically labile group of the degradable linker unit is an acid-labile group that can remain intact during circulation at neutral pH and hydrolyze under acidic conditions to release the Ras inhibitor, e.g., KRas mutant inhibitor, for example, in an acidic tumor environment or upon internalization into endosomal (pH 5.0-6.5) and lysosomal (pH 4.5-5.0) cellular compartments. This pH-dependent release mechanism can be optimized by chemical modification to finely tune the release of the Ras inhibitor, e.g., KRas mutant inhibitor, for a specific pH. Examples of such acid-labile groups include hydrazones, hydrazines, acetals, orthoesters, or imine groups. In some embodiments, the degradable linker unit contains a reducible group, such as a disulfide group. This group is reduced when the ADC is internalized into cells due to the more reducing environment provided by the cytosol (e.g., reductive glutathione) in cells, thereby releasing the drug. Irregular blood flow in tumor cells can induce hypoxic conditions, leading to increased reductase activity and elevated glutathione concentrations, which favors the selective release of drugs in tumor cells for linkers containing disulfide bonds. In some embodiments, the degradable linker unit is an enzyme-degradable linker unit and is more stable in plasma and extracellular environments than chemically labile linkers. Such linkers can be peptide-based or include a peptide region, or be non-peptide linkers, such as peptidomimetics, or sugars, esters, and amides. Such linkers can be cleaved by tumor-specific enzymes, for example, tumor-specific proteases with increased abundance in tumors and / or the tumor environment, including but not limited to lysosomal proteases, such as cathepsins (e.g., cathepsin B), legumain, MMP-2 / 9, plasmin, esterases, amidases, glutathione, etc. Generally, an enzyme-cleavable linker unit can be composed of a self-immolative linker, a cleavable linker, optionally a property-modulating unit, optionally a linker unit, and an antibody linker. The self-immolative linker connects the drug P to the cleavable linker, facilitating the release of the active drug molecule from the remainder of the ADC, such as p-aminobenzyl, p-hydroxybenzyl, p-aminobenzyloxycarbonyl, p-hydroxybenzyloxycarbonyl, etc.; the cleavable linker contains, under enzyme-based release mechanisms, peptides or peptide analogs, esters (e.g., carbamates, sulfates), amides, disulfide-containing moieties, sugars, etc., that can be recognized by enzymes; the addition of a property-modulating unit may be beneficial for improving the properties of the ADC, such as stability in the bloodstream, efficacy of the ADC at the target site, and optimizing the hydrophilicity of the ADC. For example, when the drug is highly hydrophobic, the addition of a moiety such as a PEG unit can be considered (but not required) to optimize the hydrophilicity of the ADC, e.g., reducing precipitation and aggregation; the antibody linker connects the antigen-targeting antibody or antigen-binding fragment to the remainder of the conjugate and has a functional group capable of forming a bond with a functional group on the antibody. In one aspect, the linker unit L in the ADC of formula (X) of the present disclosure has the structure of formula (II): -A(S)-B(D1)-D-E(D1)-G-                 (II), wherein A is a self-immolative linker; S is an optional solubilizing sugar unit; B is a cleavable linker, which is absent, or is selected from a peptide residue of 2-8 amino acids, preferably a dipeptide, tripeptide, or tetrapeptide; an amide bond-containing moiety; a carbamate-containing moiety; a thioether bond-containing moiety; D and D1 are each independently an optional property-modulating unit, which when present is selected from polyethylene glycol (PEG), hydrophilic peptide, cyclodextrin unit, polyamine, polyamide, polysaccharide, dendrimer, and bifunctional hydrocarbon chain; E is an optional present linker unit; G is an antibody linker connected to Ab. Accordingly, the composition of the ADC of the present disclosure can be represented as: [P-A(S)-B(D1)-D-E(D1)-G]q- Ab. In another aspect, the linker unit L in the ADC of formula (X) of the present disclosure has the structure of formula (II'): -J-B(D1)-D-E(D1)-G-                 (II’), wherein J is a self-immolative linker; B is a cleavable linker, which is absent, or is selected from a peptide residue of 2-8 amino acids, preferably a dipeptide, tripeptide, or tetrapeptide; an amide bond-containing moiety; a carbamate-containing moiety; a thioether bond-containing moiety; D and D1 are each independently an optional property-modulating unit, which when present is selected from polyethylene glycol (PEG), hydrophilic peptide, cyclodextrin unit, polyamine, polyamide, polysaccharide, dendrimer, and bifunctional hydrocarbon chain; E is an optional present linker unit; G is an antibody linker connected to Ab. Accordingly, the composition of the ADC of the present disclosure can be represented as: [P-J-B(D1)-D-E(D1)-G]q- Ab. General, specific, or preferred embodiments for each possible component of the linker unit L are described below. It should be noted that the present disclosure encompasses linker units L obtained by any combination of the general, specific, or preferred embodiments of each component with the general, specific, or preferred embodiments of any one or more of the remaining components; accordingly, the present disclosure encompasses ADC compounds obtained by any combination of the linker units obtained by said any combination with the general, specific, or preferred embodiments of the antibody and drug moieties defined herein. G—Antibody Linker The role of the antibody linker is to connect the antigen-targeting antibody or antigen-binding fragment to the remainder of the conjugate and has a functional group capable of forming a bond with a functional group on the antibody. In some embodiments, the antibody linker has a nucleophilic group capable of interacting with a reactive electrophilic group on the antibody to form a covalent bond between the antibody and the linker unit. The electrophilic group on the antibody includes, but is not limited to, aldehyde and ketone carbonyl groups, and the nucleophilic group on the antibody linker includes, but is not limited to, hydrazide, hydroxylamine, amino, hydrazine, thiosemicarbazone, carboxylic acid hydrazide, and aryl hydrazide. In other embodiments, the antibody linker has an electrophilic group capable of interacting with a reactive nucleophilic group on the antibody to form a covalent bond between the antibody and the linker unit. The nucleophilic group on the antibody includes, but is not limited to, thiol, hydroxyl, or amino functional groups, and the electrophilic group on the antibody linker includes, but is not limited to, maleimide, haloacetamide groups, activated disulfides, active esters such as NHS esters or HOBt esters, haloformates, acyl halides, alkyl halides, or benzyl halides such as haloacetamide. In some embodiments, the bond formed between the antibody linker and the antibody is a thioether, amide, ester, carbamate, carbonate, urea, disulfide, or ether. G in the linker unit L of formula (II) or (II') of the ADC of the present disclosure has the following structure: -G1-G2-G3-, wherein: G1 is a bonding atom from Ab, such as S, N, or C atom; G2 is selected from: • a 5-10 membered heterocyclyl group containing 1 or 2 heteroatoms selected from N, S, and O, wherein ring carbon atoms are optionally oxidized; ; • *---CH2--CONH--- *—s—e— ---CH2---C *^=N--NH- H *^=N--N C— wherein the left * indicates the point of attachment to G1, and the right of attachment to G3; indicates the point G3 is selected from a bond, -C1-10 alkylene-C(=O)-, -C3-10 alkynylene-C(=O)-, -C3-10 alkenylene- C(=O)-, -C1-10 heteroalkylene-C(=O)-, -C3-8 cycloalkylene-C(=O)-, -O-C1-10 alkylene-C(=O)-, -C6- 10 arylene-C(=O)-, -C1-10 alkylene-C6-io arylene-C(=O)-, -C6-10 arylene-Ci-10 alkylene-C(=O)-, -C1-10 alkylene-C3-8 cycloalkylene-C(=O)-, -C3-8 cycloalkylene-C1-10 alkylene-C(=O)-, -C3-8 heterocyclylene-C(=O)-, -C1-10 alkylene-C3-8 heterocyclylene-C(=O)-, -C3-8 heterocyclylene-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C3-10 alkynylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C3-10 alkenylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C1-10 heteroalkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C3-8 cycloalkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -O-C1-10 alkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C6-10 arylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C6-10 arylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C6-10 arylene-C1-10 alkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C3-8 cycloalkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C3-8 cycloalkylene-C1-10   alkylene-C(=O)-NH-C1-10   alkylene-O-C1-10   alkylene-C(=O)-,   -C3-8 heterocyclylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C3-8 heterocyclylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C3-8 heterocyclylene-C1-10 alkylene-C(=O)-NH-C1-10 alkylene-O-C1-10 alkylene-C(=O)-, -C1-10 alkylene-NH-, -C1-10 heteroalkylene-NH-, -C3-8 cycloalkylene-NH-, -O-C1-10 alkylene-NH-, -C6-10 arylene-NH-, -C1-10 alkylene-C6-10 arylene-NH-, -C6-10 arylene-C1-10 alkylene-NH-, -C1-10 alkylene-C3-8 cycloalkylene-NH-, -C3-8 cycloalkylene-C1-10 alkylene-NH-, -C3-8 heterocyclylene-NH-, -C1-10 alkylene-C3-8 heterocyclylene-NH-, and -C3-8 heterocyclylene-C1-10 alkylene-NH-, wherein each group attached to -C(=O)- or -NH- in G3 is optionally substituted by Bu, and G3 is connected via its -C(=O)- or -NH-to the linker unit E (when present), or the property-modulating unit D (when present and E is absent), or the cleavable linker B (when both E and D are absent), and the other end group is connected to G2. In some embodiments, each group attached to -C(=O)- or -NH- in G3 is optionally substituted by the following Bu group: H, deuterium, halogen, NO2, CN, -ORh, -ORh, -N(Rh)2, -CORh, -CO2 Rh, -C-(O)C(O)Rh, -C(O)CH2C(O)Rh, -S(O)Rh, -SO2Rh, C(O)N(Rh)2, -SO2N(Rh)2, -OC(O)Rh, - N(Rh)SO2Rh, and -C1-6 alkyl optionally substituted by the preceding groups, wherein Rh is H or -C1-6 alkyl optionally substituted by halogen, or wherein two Rh groups attached to the same N atom together with the nitrogen to which they are attached form a 4-7 membered heterocyclyl group. Preferably, the substituent on G3 is an aminoalkyl moiety, such as -(CH2)i—6NH2, -(CH2)i-6NHRh, or -(CH2)i-6N(Rh)2, or wherein two Rh groups attached to the same N atom together with the nitrogen to which they are attached form an azetidinyl, pyrrolidinyl, or piperidinyl group. In other embodiments, each group attached to -C(=O)- or -NH- in G3 is optionally substituted by the Bu group of formula (A):     0    '   / p      (A), wherein, T0 is -C1-6 alkylene-; T is selected from -C(Ra)2-, -O-, -NRa-, or is absent; Q is selected from -CO-, -O-, -NRa-, or is absent; U is selected from glycosyl or a derivative thereof, * , and a hydrophilic peptide comprising Ra is selected from H or -C1-6 alkyl, preferably H or -CH3; O R II / du the subunit     R'          is selected from natural amino acid residues and unnatural amino acid residues; p is an integer from 0 to 4, for example 0-2, 1-2, 2-4; t is an integer from 0 to 20, for example 0-8, 0-6, 0-4, 0-2, 1-20, 1-10, 2-10, 2-8, 2-6, 2-4, 4-14, 6-10, 6-12, 8-10, 8-14. The glycosyl or derivative thereof among the substituents carried by G3 of the antibody linker of the ADC of the present disclosure is selected from monosaccharide groups, disaccharide groups, oligosaccharide groups, or polysaccharide groups or derivatives thereof, preferably the monosaccharides or disaccharides or derivatives thereof as generally, specifically, or preferably defined in the "Linker Unit L" section herein for the solubilizing sugar unit S, more preferably the monosaccharides or disaccharide groups or derivatives thereof exemplified in Tables 3 and 4. In some embodiments, U is a monosaccharide or disaccharide or derivative thereof as defined herein and is linked via a glycosidic bond (-O-sugar residue); in other embodiments, U is an amino sugar or derivative thereof as defined herein and is linked via an amino group, preferably an amino sugar derivative of a monosaccharide or disaccharide; in other embodiments, U is a sugar acid or uronic acid or derivative thereof as defined herein and is linked via a carbonyl group. In the hydrophilic peptide carried by the ADC of the present disclosure, the amino acid residues as subunits can be the conventional 20 natural amino acids. Correspondingly, the combinations of values for R, R', R" in the repeating subunit -CO-CR'R"-NR- correspond to alanine (Ala), arginine (Arg), aspartic acid (Asp), asparagine (Asn), histidine (His), glycine (Gly), glutamic acid (Glu), glutamine (Gln), phenylalanine (Phe), lysine (Lys), leucine (Leu), serine (Ser), tyrosine (Tyr), threonine (Thr), isoleucine (Ile), proline (Pro), tryptophan (Trp), valine (Val), cysteine (Cys), methionine (Met). Preferred are polar natural amino acids, such as arginine, serine, threonine, tyrosine, cysteine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, histidine, glycine, tryptophan. The hydrophilic peptide can be a repeat of a single unit or a mixed repeat of different subunits. In the hydrophilic peptide carried by the ADC of the present disclosure, the amino acid residues as subunits can also be amino acids other than the conventional 20 natural amino acids, such as ornithine (Orn), p-alanine (p-Ala), citrulline (Cit), sarcosine (Sar), and those amino acids where R, R', R" in the repeating subunit -CO-CR'R"-NR- differ from the corresponding groups or moieties in the 20 natural amino acids. For example, R, R', R" are selected from alkyl, aryl, acyl, amido, ketone, azido, hydroxyl, mercapto, hydrazine, cyano, quaternary ammonium, halogen, hydrazide, alkenyl, alkynyl, ether, thiol, seleno, sulfonic acid, sulfate, borate, phosphono, phosphate, heterocycle, enone, imine, aldehyde, ester, thioacid, hydroxylamine, amino, etc., or any combination thereof, or groups containing alkyl, aryl, acyl, amido, ketone, azido, hydroxyl, mercapto, hydrazine, cyano, quaternary ammonium, halogen, hydrazide, alkenyl, alkynyl, ether, thiol, seleno, sulfonic acid, sulfate, borate, phosphono, phosphate, heterocycle, enone, imine, aldehyde, ester, thioacid, hydroxylamine, amino, etc. Preferred are those amino acids where R, R', and / or R" contain hydrophilic groups, such as R, R', R" each independently is carboxyl, sulfonic acid, sulfate, phosphate, amino, amido, quaternary ammonium, ether, mercapto, or hydroxyl, or is a group containing carboxyl, sulfonic acid, sulfate, phosphate, amino, amido, quaternary ammonium, ether, mercapto, and / or hydroxyl, such as alkyl or aryl, e.g., C1-6 alkyl. In some embodiments, the amino acid units of the hydrophilic peptide comprise natural amino acid repeating units, preferably selected from arginine, serine, threonine, tyrosine, cysteine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, histidine, glycine, tryptophan; in other embodiments, the hydrophilic peptide comprises amino acid repeating units other than the 20 natural amino acids listed above, such as ornithine (Orn), citrulline (Cit), sarcosine (Sar); in other embodiments, the hydrophilic peptide is a mixed hydrophilic peptide comprising said natural amino acids and said non-conventional amino acids. O     R II                       I In some embodiments, in the subunit     R' R , preferably R, R', R" are each independently H, -C1-6 alkyl, carboxyl, sulfonic acid, sulfate, phosphate, amino, amido, quaternary ammonium, ether, mercapto, or hydroxyl, or a group containing a hydrophilic group such as carboxyl, sulfonic acid, sulfate, phosphate, amino, amido, quaternary ammonium, ether, mercapto, and / or hydroxyl, such as aryl or C1-6 alkyl; more preferably R, R', R" are each independently H, -C1-6 alkyl, carboxyl, sulfonic acid, phosphate, amino, amido, quaternary ammonium, mercapto, or hydroxyl, or a group containing a hydrophilic group such as carboxyl, sulfonic acid, phosphate, amino, amido, quaternary ammonium, mercapto, and / or hydroxyl, such as aryl or C1-6 alkyl. In some embodiments, the G3 part of the antibody linker of the ADC of the present disclosure is substituted by a Bu group of formula (A), and wherein U in formula (A) is a hydrophilic peptide O R JUL comprising         R'               as generally or specifically defined above. In some embodiments, the hydrophilic peptide is linked via the carboxyl terminus, and in other embodiments, the hydrophilic peptide is linked via the amino terminus. It should be noted that the hydrophilic peptide is involved in the definition of multiple structural fragments throughout the present disclosure, and its definition herein applies to the definition given for the fragment of formula (A). For the ADC of the present disclosure, the hydrophilic peptide carried, for example but not linked via the carboxyl terminus or terminus, wherein R is as defined above, including but not limited to the amino residues of the various amino acids listed for the hydrophilic peptide herein, Ra is selected from H or -C1-6 alkyl, preferably H or -CH3; preferably comprising 4-14 units 10 of polysarcosine, polyarginine, or polyglycine, polysarcosine. more preferably comprising 6-12 units of It should be noted that each example of exemplified below for the hydrophilic peptide is Ra N  Y I                          II Ra    O - t Ra I Ra a specific example of the hydrophilic peptide, especially and Ra , wherein when Ra on the N 15 of the repeating unit is methyl, it represents the polysarcosine preferably carried by the ADC of the present disclosure. In some embodiments, U is selected from and the hydrophilic peptide linked Ra 0^        Ra via the amino terminus, e.g., ; in other embodiments, U is selected from , and the hydrophilic peptide linked via the carboxyl terminus, e.g., , wherein Ra is selected from H or -C1-6 alkyl, preferably H or - CH3. In some embodiments, To is -C1-4 alkylene-, preferably -C1-2 alkylene-, more preferably methylene. In some embodiments, in the fragment, T is -O-, e.g., ), or T is -C(Ra)2-, e.g., ), or T is -NRa-, e.g., T                                                              0               । ), , or T is absent, e.g., M 'P^ ,   ^p5 R       ,       / ^, In some embodiments, in the          ' p r  fragment, T is absent, p is 0-4, e.g., 0-2, and Q is -CO-, i.e., ; or T is -C(Ra)2-, p is 0-4, e.g., 0-2, and Q is -CO-, i.e., ; for example but not limited to 0 or <- r . Further, in such embodiments, U is preferably selected from               * and a hydrophilic peptide such as or an amino sugar or derivative thereof as defined herein linked via an amino group, preferably an amino sugar derivative of a monosaccharide or disaccharide, more preferably the amino sugar or derivative thereof shown in Table 3 or Table 4. In some embodiments, in the fragment, T is absent, p is 0-4, e.g., 0-2, and Q is Ra Ry RN / selected from -O- or-NRa-, i.e.,    ' 'P ,    ' 'P ; or T is -C(Ra)2-, p is 0-4, e.g., 0-2, and Q is selected from -O- and -NRa-, i.e., or ; for example but not limited to r' or7- r*. Further, in such embodiments, U is preferably selected from a sugar acid or derivative thereof as defined herein linked via a carbonyl group, preferably a sugar acid derivative of a monosaccharide or disaccharide, more preferably the sugar acid derivatives o shown in Table 3 or Table 4; 1 ; and a hydrophilic peptide such In some embodiments, Ra Q is Ra absent, and the fragment is selected from Ra ,                                   , H p , wherein p is 0-4, preferably 1-4, e.g., 1-2, such as or . Further, in such embodiments, U can be a glycosyl v°- or derivative thereof linked via a glycosidic bond, e.g., Sugar residue , where the sugar residue is linked via ethylene glycol; or U is an amino sugar or derivative thereof linked via an amino Sugar residue N‘ H group, e.g., In some embodiments, t is an integer from 1~20, e.g., 2-10, 2-8, 2-6, 2-4, 4-10, 4-14, 6-10, 612, 8-10, 8-14. In some embodiments, Gi is an S atom; in other embodiments, Gi is an N atom; in other embodiments, Gi is a C atom. In the ADC of the present disclosure, preferred Gi is a sulfur atom of Ab. In some embodiments, G2 is a 5-10 membered heterocyclyl group, preferably a 5-6 membered heterocyclyl group containing 1 or 2 heteroatoms selected from N, O, and S, wherein ring carbon atoms are optionally oxidized, for example but not limited to , wherein the left * indicates the point of attachment to Gi, and the right wavy line indicates the point of attachment to G3. In some embodiments, G2 is selected from which are the acid-amide moieties formed after partial hydrolysis of the succinimide moiety. In a preferred embodiment, G2 is a maleimidyl group . In another preferred In some embodiments, G2 is selected from 0 II *—ch2---c ; preferably selected from In some embodiments, G3 is selected from -C1-10 alkylene-C(=O)-, -C3-10 alkynylene-C(=O)-, -10   C3-10 alkenylene-C(=O)-, -C1-10 heteroalkylene-C(=O)-, -C3-8 cycloalkylene-C(=O)-, -O-C1-10 alkylene-C(=O)-, -C6-10 arylene-C(=O)-, -C1-10 alkylene-C6-10 arylene-C(=O)-, -C6-10 arylene-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C3-8 cycloalkylene-C(=O)-, -C3-8 cycloalkylene-C1-10 alkylene-C(=O)-, -C3-8 heterocyclylene-C(=O)-, -C1-10 alkylene-C3-8 heterocyclylene-C(=O)-, -C3-8 heterocyclylene-C1-10 alkylene-C(=O)-, -C1-10 alkylene-NH-, -C1-10 heteroalkylene-NH-, -C3-8 15   cycloalkylene-NH-, -O-C1-10 alkylene-NH-, -C6-10 arylene-NH-, -C1-10 alkylene-C6-10 arylene-NH-, -C6-10 arylene-C1-10 alkylene-NH-, -C1-10 alkylene-C3-8 cycloalkylene-NH-, -C3-8 cycloalkylene-C1-10 alkylene-NH-, -C3-8 heterocyclylene-NH-, -C1-10 alkylene-C3-8 heterocyclylene-NH-, and -C3-8 heterocyclylene-Ci-io alkylene-NH-; preferably selected from -C1-10 alkylene-C(=O)-, -C3-10 alkynylene-C(=O)-, -C3-10 alkenylene-C(=O)-, -C1-10 heteroalkylene-C(=O)-, -C1-10 alkylene-C6-10 arylene-C(=O)-, -C6-10 arylene-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C3-8 cycloalkylene-C(=O)-, -C3-8 cycloalkylene-C1-10 alkylene-C(=O)-, -C1-10 alkylene-C3-8 heterocyclylene-C(=O)-, -C3-8 5   heterocyclylene-C1-10 alkylene-C(=O)-; more preferably -C1-10 alkylene-C(=O)-; wherein each group attached to -C(=O)- or NH in G3 is optionally substituted by Bu as defined above for G3, and G3 is connected via its -C(=O)- or NH to the linker unit E (when present), or the property-modulating unit D (when present and E is absent), or the cleavable linker B (when both E and D are absent), and the other end group is connected to G2. 10        In some embodiments, G3 is -C1-10 alkylene-C(=O)-, preferably -C1-5 alkylene-C(=O)-, wherein the alkylene moiety is optionally substituted by the Bu moiety described above. In some embodiments, G3 is -C1-10 alkylene-NH, preferably -C1-5 alkylene-NH-, wherein the alkylene moiety is optionally substituted by the Bu moiety described above. In exemplary embodiments, -G2-G3- can be the following groups: 15 9 , wherein G3 and Bu are each as generally or preferably defined above; G3' and G3'' are each independently selected from -C1-10 alkylene, -C3-10 alkynylene, -C3-10 alkenylene, -C1-10 heteroalkylene, -C3-8 cycloalkylene, -C6-10 arylene, -C1-10 alkylene-C6-10 arylene, -C6-10 arylene-C1-10 alkylene, -C1-10 alkylene-C3-8 cycloalkylene, -C3-8 cycloalkylene-C1-10 alkylene, -C3-8 heterocyclylene, -C1-10 alkylene-C3-8 heterocyclylene, -C3-8 heterocyclylene-C1-10 alkylene; Preferably, G3' and G3'' are each independently selected from -C1-10 alkylene, -C3-10 alkynylene, -C3-10 alkenylene, -C1-10 heteroalkylene, -C1-10 alkylene-C6-10 arylene, -C6-10 arylene-C1-10 alkylene, -C1-10 alkylene-C3-8 cycloalkylene, -C3-8 cycloalkylene-C1-10 alkylene, -C1-10 alkylene-C3-8 heterocyclylene, -C3-8 heterocyclylene-C1-10 alkylene; More preferably, G3' is -C1-10 alkylene-, preferably -C1-5 alkylene-; G3'' is -C1-5 alkylene-, preferably -C1-2 alkylene-; wherein G3' and G3" are optionally substituted by the Bu moiety as generally or preferably defined above; wherein the left * indicates the point of attachment to G1, and the right indicates the point of attachment to E (when present), or the property-modulating unit D (when present and E is absent), or the cleavable linker B (when both E and D are absent). 0                        0 In some embodiments, -G2-G3- is           0                or         0                , wherein G3' is -C1-10 alkylene-, preferably -C1-5 alkylene-, Bu is absent or is a structural fragment of formula (A). In specific embodiments,    -G2-G3-    can 0                  , e.g.,             0 G3-  can be o fragment of formula (A) are respectively as generally or specifically defined above for formula (A). In further specific embodiments, OH To o * (CH2)0, (CH2)o.4 'p Q or NH , •w*g., -G2-G3- 0 OH T, wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is absent and p is 0-4 (e.g., 0-2) and Q is selected from -O- or -NRa-, or To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is -C(Ra)2-, p is 0-4 (e.g., 0-2) and Q is -NRa- or -O-, and U is preferably selected from a sugar acid (preferably a sugar acid of a monosaccharide or disaccharide) or derivative thereof linked 10 , , a hydrophilic peptide such as via a carbonyl group, ; or 15 wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is absent and p is 0-4 (e.g., 0-2) and Q is -CO-, or To is -C1.4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is -C(Ra)2-, p is 0-4 (e.g., 0-2) and Q is -CO-, and U is preferably selected from an amino sugar (preferably an amino monosaccharide or amino disaccharide) or derivative thereof linked via an amino group, , or a hydrophilic peptide such as wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is selected from -C(Ra)2-, -O-, -NRa -, or is absent, Q is absent, p is 0-4 (e.g., 0-2, 1-2), and U is preferably selected from a glycosyl (preferably a monosaccharide or disaccharide) or derivative thereof linked via a 5 glycosidic bond, or an amino sugar (preferably an amino monosaccharide or amino disaccharide) or derivative thereof linked via an amino group; wherein t is an integer from 1 to 20, e.g., 2-10, 2-8, 2-6, 2-4, 4-10, 4-14, 6-10, 6-12, 8-10, 8-14. In some embodiments, -G1-G2-G3- is selected from the following groups: 10 specifically 15 defined above; the left * indicates the point of attachment to the remainder of the antibody, and the right       indicates the point of attachment to the linker unit E (when present), or the property- modulating unit D (when present and E is absent), or the cleavable linker B (when both E and D are absent). 10 some embodiments,    -G1-G2-G3-    is In 0 or , wherein G3' is -C1-10 alkylene-, preferably -C1-5 alkylene-, Bu is absent or is a structural fragment of formula (A). Gi be In * —G-j G1-G2-G3- can be N--(CH2),5 specific embodiments,   -G1-G2-G3-   can OH T, , wherein To, T, Q, U, p, and the fragment of formula (A) are respectively as generally or specifically defined above for formula (A). * (CH2)0.4 or In further specific embodiments, -G1-G2-G3- is or e.g., or NH OH To / Q\ p u , wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is absent and p is 0-4 (e.g., 0-2) and Q is selected from -O- or -NRa-, or To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is -C(Ra)2-, p is 0-4 (e.g., 0-2) and Q is -NRa- or -O-, and U is preferably selected from a sugar acid (preferably a sugar acid of a monosaccharide or disaccharide) or derivative thereof linked via a carbonyl group, , a hydrophilic peptide such as wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is absent and p is 1-4 (e.g., 1-2) and Q is -CO-, or To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is - C(Ra)2-, p is 0-4 (e.g., 0-2) and Q is -CO-, and U is preferably selected from an amino sugar (preferably an amino monosaccharide or amino disaccharide) or derivative thereof linked via an amino group, 1 , or a hydrophilic peptide such as wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is selected from -C(Ra)2-, -O-, -NRa-,, or is absent, Q is absent, p is 0-4 (e.g., 0-2, 1-2), and U is preferably selected from a glycosyl (preferably a monosaccharide or disaccharide) or derivative thereof linked via a glycosidic bond, or an amino sugar (preferably an amino monosaccharide or amino disaccharide) or derivative thereof linked via an amino group; wherein t is an integer from 1~20, e.g., 2-10, 2-8, 2-6, 2-4, 4-10, 4-14, 6-10, 6-12, 8-10, 8-14. In exemplary embodiments, G (-G1-G2-G3-) in formula (II) or (II') of the present disclosure has the following structures: In some preferred embodiments, G in formula (II) or (II') of the present disclosure has the following structures: 10 , , s— and the respective fragments above maleimide *—s where the NH S--- HO O etc. E—Linker Unit The linker unit E in the linker unit L of formula (II) or (II') of the ADC of the present disclosure connects the antibody linker G to the property-modulating unit D, or when D is absent, connects the antibody linker G to the cleavable linker B, to add extra distance between the antibody linker and the cleavable linker B, potentially aiding in the activation of B. In some embodiments, the linker unit E is selected from a direct bond, -C1-5 alkylene-, -NH-, -NH-C1-5 alkylene-heteroaryl (such as a 5- or 6-membered nitrogen-containing heteroaryl, e.g., triazolyl), and the following groups: Rg               Rg . I                u N—Rf—O—Rf—N-^— H                                      । —C—R—O—Rf—N— Rg      Rg      Rg . I          I          u N—Rf—N—Rf—N^- O              Rg ,11                   I > C—Rf—N—Rf—N— wherein when present, E is connected via its -C(=O)- or -NH- end to the property-modulating unit D (when present) or the cleavable linker B as appropriate, and the other end is connected via -C(=O)- or -NH- to G3 as appropriate; Rg is each independently selected from H and -C1-6 alkyl, preferably H or -C1-3 alkyl; Rf is selected from -C1-6 alkylene-, -arylene-, -C1-10 heteroalkylene-, -C3-8 heterocyclylene-, -C1-10 alkylene-C6-10 arylene-, -C6-10 arylene-C1-10 alkylene-, -C1-10 alkylene-C3-8 cycloalkylene-, -C3-8 cycloalkylene-C1-10 alkylene-, -C1-10 alkylene-C3-8 heterocyclylene-, -C3-8 heterocyclylene-C1-10 alkylene-; It should be noted that, when present, each specific definition of E above can be repeated consecutively 1-10 times, preferably 1-4 times, in different head-to-tail orientations, such as 1, 2, 3, and 4 times. s II                                          I C—Rf—O—Rf—N^-In a specific embodiment, the linker unit E is                            ^, wherein Rf is each independently selected from -C1-6 alkylene-, preferably -C2-4 alkylene, Rg is H or C1-3 alkyl, e.g., , wherein the left wavy line is connected to the cleavable linker B, and the right wavy line is connected to the antibody linker G. In another specific embodiment, the linker unit E is a direct bond; in another specific embodiment, the linker unit E is -C1-4 alkylene-; in another specific embodiment, the linker unit E is -NH-. D and D1—Property-Modulating Unit The addition of the property-modulating unit D or D1 in the linker unit L of formula (II) or (II') of the ADC of the present disclosure may be beneficial for improving the properties of the ADC, such as stability in the bloodstream, improving hydrophilicity, leading to reduced clearance and increased exposure. However, increasing the number of D or D1 units can also lead to increased molecular weight and hydrodynamic radius of the ADC, which can reduce diffusion, and reduced diffusivity may decrease the ability of the ADC to penetrate tumors. Due to these two competing pharmacokinetic effects, a moderate amount of D or D1 is needed to reduce the clearance of the ADC, thereby increasing plasma exposure, but not so large as to reduce its diffusivity to the extent that it interferes with the ability of the ADC to reach the intended target cell population. Property-modulating unit D is present in the linker unit in a tandem manner, and D1 is present in a branched manner. D can be directly connected between B and E, or can be connected between B and E via an additional linking group, such as amino, carbonyl, alkylcarbonyl, amide, ester, urea, disulfide bridge, carbamate, hydrazone, imine, oxime, triazolyl, maleimidyl, alkenyl, alkynyl, or alkylene. For example, D can be connected to the cleavable linker B via -NH-, -C(=O)-, -C1-4 alkylene, -C1-4 alkylene-C(=O)-, -NH-C(=O)-(CH2OCH2)-C(=O)-, -C1-4 alkylene-NH-C(=O)-(CH2OCH2)-C(=O)-. In some embodiments, D or D1 is absent. In some embodiments, D or D1 is selected from polyamines, for example but not limited to polyethyleneimine, polylysine, spermine, dimeric polyamines, arginine, amidine, protamine, cationic lipids, cationic porphyrins, quaternary ammonium salts of polyamines, a-helical peptides. In some embodiments, D or D1 is selected from peptides, preferably hydrophilic peptides. In some embodiments, D or D1is a cyclodextrin unit. In some embodiments, D or D1 is a polyamide. In some embodiments, D or D1 is a polysaccharide, dendrimer, or bifunctional hydrocarbon chain. In some embodiments, D or D1 is PEG. In the embodiments of the present disclosure, polydisperse PEG (non-uniform mixture of sizes and molecular weights), monodisperse PEG (single chain length and molecular weight), and discrete PEG can be used as part of the property-modulating unit in the ADC of the present disclosure. Preferred PEG is discrete PEG, which are compounds synthesized in a stepwise manner rather than via a polymerization process, providing a single molecule with a defined chain length. The ADC of the present disclosure can contain one or more PEG chains consisting of at least two ethylene oxide (CH2CH2O) subunits. PEG chains can be linked together, for example, in a linear, branched, or star configuration. Typically, at least one PEG chain is functionalized so that it can be covalently linked to other components in the linker unit, with functionalization methods including, for example, via amine, thiol, NHS ester, maleimide, alkyne, azide, carbonyl, or other functional groups. For example, one end of a PEG chain can be functionalized to covalently attach to an appropriate site on the linker unit, and the other end (or multiple ends) can be free and unbound, i.e., not attached to other components in the ADC, and can take the form of methoxy, carboxylic acid, alcohol, or other suitable functional groups; alternatively, the PEG chain can be covalently linked in a tandem manner between two components of the linker unit, for example, between the linker unit E and the cleavable linker B. The linkage of the PEG chain to the components within the linker unit can be via cleavable bonds, which can be bonds that are substantially insensitive to cleavage during circulation in plasma but sensitive to cleavage in intracellular or intratumoral environments. Exemplary linkages include, but are not limited to, amide bonds, ether bonds, ester bonds, hydrazone bonds, oxime bonds, disulfide bonds, peptide bonds, or triazole bonds, etc. Methods for attaching PEG units to the linker unit of ADCs are well known to those skilled in the art. For example, PEG can be covalently bound to amino acid residues via reactive groups. Reactive groups are those to which an activated PEG molecule can bind, such as free amino or carboxyl groups, e.g., thiol groups on cysteine residues can also be used as reactive groups for linking PEG. In some embodiments, methoxylated PEG ("mPEG") with different reactive moieties can also be used to link PEG to amino groups. Non-limiting examples of such reactive moieties include succinimidyl succinate (SS), succinimidyl carbonate (SC), mPEG-imidate, p-nitrophenyl carbonate (NPC), succinimidyl propionate (SPA), and cyanuric chloride. Correspondingly, non-limiting examples of such mPEG include mPEG-succinimidyl succinate (mPEG-SS), mPEG-succinimidyl carbonate (mPEG-SC), mPEG-imidate, mPEG-p-nitrophenyl carbonate (mPEG-NPC), mPEG-succinimidyl propionate (mPEG-SPA), mPEG-N-hydroxy-succinimide (mPEG-NHS), mPEG-cyanuric chloride, mPEG2-lysinol-NPC, and mPEG2-Lys-NHS. In some embodiments, the PEG unit comprises one or more linear PEG chains, each PEG chain having 2-12 ethylene oxide (CH2CH2O) subunits, for example at least 2, at least 3, at least 4, at least 5, at least 6, at least 7, at least 8, at least 9, at least 10, at least 11, at least 12 ethylene oxide (CH2CH2O) subunits. In preferred embodiments, the PEG unit comprises at least 2, at least 4, at least 6, at least 8, at least 10, or at least 12 ethylene oxide (CH2CH2O) subunits, for example, the PEG unit comprises 2 to 12, 2 to 10, 2 to 8, 2 to 6, 2 to 4, 4 to 12, 4 to 10, 4 to 8, 4 to 6, 6 to 12, 6 to 10, 6 to 8, 8 to 12, or 8 to 10 subunits. Exemplary embodiments of the PEG moiety D linking the cleavable linker B and the linker unit E include, but are not limited to, the following: Exemplary embodiments of linear PEG units (i.e., one end linked to the linker unit, the other end being a cap) include: wherein the left wavy line indicates the point of attachment to E or G3 (or to E or B in the case of branched PEG as appropriate), the right wavy line indicates the point of attachment to B, and each subscript c is independently selected from integers 2-12. In some embodiments, c is 2, 4, 8, or 12. In some embodiments, c is 2. In some embodiments, c is 4. In some embodiments, c is 8. In some embodiments, c is 12. B—Cleavable Linker In one aspect, the cleavable linker B in the linker unit L o...

Claims

1. An antibody-drug conjugate of formula (X) or a pharmaceutically acceptable salt or solvate thereof:[P-L]q-Ab                  (X)wherein,Ab represents an antibody or antigen-binding fragment that binds to a target antigen;q represents the number of [P-L] units connected to Ab, which is an integer or non-integer of at least 1;L represents a linker unit connecting P to Ab;P represents a Ras mutant inhibitor compound.

2. The antibody-drug conjugate according to claim 1, wherein the Ras mutant inhibitor compound isa compound of formula (I):(Rl2>mor a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, prodrug, or solvate thereof,wherein:M is selected from N or C-Ri;M' is selected from N or C-Ri';Ri and Ri' are each independently selected from H, halogen, CN, -C1-6 alkyl optionally substituted by halogen, and -OC1-6 alkyl optionally substituted by halogen;Ra is selected from H, halogen, CN, -C1-6 alkyl optionally substituted by halogen, -C2-6 alkynyl optionally substituted by halogen, and -OC1-6 alkyl optionally substituted by halogen or deuterium;X is selected from CH2, N, and O;R2 and R2' are each independently selected from H, OH, or -C1.6 alkyl optionally substituted by halogen; or R2 and R2' attached to non-adjacent ring carbon atoms together form an intra-ring bridge -(CH2)1-2- or -CH2=CH2-; or R2 and R2' attached to the same ring carbon atom together with the ring carbon atom to which they are attached form a 4-6 membered spirocycloalkyl or a 4-6 membered spiroheterocycloalkyl containing 1 or 2 heteroatoms selected from N and O;R3 is selected from H, -NH2, -NHC1-6 alkyl, -N(Ci-6 alkyl)2, and -OC1-6 alkyl;R4 is selected from -CN, halogen, -NO2, -C2-6 alkynyl optionally substituted by halogen, and -C1-6 alkyl optionally substituted by halogen;R5 is selected from H, -CN, halogen, -NO2, and halogen-substituted -C1-6 alkyl;R6 is selected from H, halogen, CN, -C1-6 alkyl, and -C2-6 alkynyl, wherein the -C1-6 alkyl and -C2-6 alkynyl are each independently optionally substituted by halogen;R7, R7', R8, and R8' are each independently selected from H, halogen, CN, -NO2, and -C1-6 alkyl optionally substituted by halogen;V and W are each independently selected from H, halogen, -C1-6 alkyl, OH, and NH2;Z is selected from O, N, and CH2;R9 and R10 are each independently selected from H, deuterium, -C1-6 alkyl, and -(CH2)n-C3-6 cycloalkyl, wherein the -C1-6 alkyl and -C3-6 cycloalkyl are each independently optionally substituted by deuterium, halogen, or -O-C1-6 alkyl, or R9 and R10 attached to the same carbon atom together with the carbon atom to which they are attached form a C3-4 cycloalkyl;R11 is selected from H, -C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, and -(CH2)n-C3-6 cycloalkyl, wherein the C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, or C3-6 cycloalkyl are each independently optionally substituted by deuterium, halogen, CN, or -O-C1-6 alkyl;R12 is selected from H, halogen, -CN, -OH, -NH2, -NHC1-6 alkyl, -N(Ci-6 alkyl)2, -O-C1-6 alkyl, -O-C3-6 cycloalkyl, -C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, -(CH2)n-C3-6 cycloalkyl, and =C(Rd)2, wherein Rd is each independently selected from H, halogen, and -C1-6 alkyl optionally substituted by halogen, wherein each occurrence of C1-6 alkyl, -C2-6 alkenyl, -C2-6 alkynyl, or C3-6 cycloalkyl is each independently optionally substituted by halogen, CN, or -OC1-6 alkyl;R13 is selected from H, -C1-6 alkyl, and -(CH2)n-C3-6 cycloalkyl, wherein the -C1-6 alkyl and -C3-6 cycloalkyl are each independently optionally substituted by halogen or -O-C1-6 alkyl;k is selected from 0 or 1;m is selected from 0 to 6;n is selected from 0 to 2;wherein the compound of formula (I) is bonded to the linker unit L via the ring NH present inthe      ।         fragment thereof, and / or via the OH present on the side-chain naphthalene orbenzothiophene ring.

3. The antibody-drug conjugate according to claim 2, wherein the structural fragmentRaPreferably,in formula (I) isRRfRaor      RlM is C-R1 and M' is C-Ri', wherein Ri is selected from halogen or -Ci-6 alkyl optionally substituted by halogen, Ra is H, and Ri' is halogen; or M is N and M' is C-Ri', wherein Ra is selected from H, -C2-6 alkynyl, and -OC1-6 alkyl, and Ri' is halogen,More preferably,M is C-Ri and M' is C-Ri', wherein Ri is selected from F or Cl, or -Ci-3 alkyl substituted by halogen, Ra is H, and Ri' is F; or M is N and M' is C-Ri', wherein Ra is selected from H, -C2-4 alkynyl, and -OCi-3 alkyl optionally substituted by deuterium, and Ri' is F;and / orwherein in the structural fragment       v        in formula (I), R3 is selected from -NH2, -NHCi-6 alkyl, and N(Ci-6 alkyl)2; R4 is selected from -CN, halogen, -NO2, and -C2-6 alkynyl substituted by halogen; V is selected from H, -Ci-6 alkyl, and halogen; R7 and R7' are each H, or each are halogen, or one of them is H and the other is halogen or halogen-substituted Ci-6 alkyl, or one is halogen and the other is halogen-substituted Ci-6 alkyl,Preferably, the structural fragment       vis         v      , V is H, R7 and R7' areeach H, or one of them is H and the other is halogen, orR5i\R6n.rXt Rs'wherein in the structural fragment     w       in formula (I), W is OH; R5 is H or halogen;R6 is selected from halogen, -C2-6 alkynyl, and -Ci-6 alkyl; R8 and R8' are each H; or R8 and R8' are each halogen; or one of R8 and R8' is H and the other is selected from halogen, CN, and NO2; or one of R8 and R8' is H and the other is selected from -Ci-6 alkyl optionally substituted by halogen; or oneof R8 and R8‘ is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen,R.OHPreferably, the structural fragment     wis, wherein R5 is halogen, R6 isselected from -C2-6 alkynyl;and / orwherein the structural fragment       ।         in formula (I) is       ।       , wherein R2 andR2' attached to non-adjacent ring carbon atoms together form an intra-ring bridge -CH2-, -CH2CH2-,HNor -CH2=CH2-, preferablyand / or10wherein Z is O, and the structural fragment connected to Z isRl1 , more preferably          Rl1, preferably4. The antibody-drug conjugate according to claim 2 or 3, whereinR9 and R10 are both H, or one or both are deuterium; and / or15wherein R11 is -C1-6 alkyl, wherein the hydrogen atom is optionally replaced by one or more isotope deuterium; and / orwherein R12 is selected from -C1-6 alkyl optionally substituted by halogen and =C(Rd)2, wherein Rd is each independently selected from H and halogen, and m is 1 or 2; and / orwherein R13 is -C1-6 alkyl, preferably -C1-3 alkyl, more preferably -CH3.

5. The antibody-drug conjugate according to any one of claims 1 to 4, wherein the structuralRl1           is selected fromfragment5        6. The antibody-drug conjugate according to any one of claims 1 to 5, wherein the compound offormula (I) has any one of the following sub-general formulas:corresponding claims 1 to 11; preferablywhen M is C-Ri and M' is C-Ri', Ri is selected from F or Cl, or -Ci-3 alkyl substituted by halogen, Ra is H, and Ri' is F; or when M is N and M' is C-Ri', Ra is selected from H, -C2-4 alkynyl, and -OCi-5   3 alkyl optionally substituted by deuterium, and Ri' is F;R3 is -NH2, R4 is -CN, V is H, R7 and R7' are each H, or one of them is H and the other is halogen;R5 is halogen, R6 is selected from -C2-6 alkynyl, R8 and R8' are each H, W is OH;R9 and Rio are both H, or one or both are deuterium;Rii is -Ci-3 alkyl, wherein the hydrogen atom is optionally replaced by one or more isotope i0 deuterium;Ri2 is selected from -Ci-3 alkyl optionally substituted by halogen and =C(Rd)2, wherein Rd is each independently selected from H and halogen;m is i or 2;Ri3 is -Ci-3 alkyl.i5        7. The antibody-drug conjugate according to any one of claims i to 6, wherein the Ras inhibitorcompound is selected from:P1                          P2                         P3                          P4P5                                             P6                                         P7stereoisomers, tautomers, stable isotopic variants, pharmaceutically acceptable salts, or solvates thereof.5        8. The antibody-drug conjugate according to claim 1, wherein the Ras inhibitor compound hasany one of the following sub-general formulas:(I’-A-1)(I’-A-2)or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof,wherein M, M', X, Z, V, W, Ri, Ri', R3, R4, R5, R6, R7, R7', Rs, Rs', R9, R10, R11, R12, R13, k, m,n, the structural fragmentsIRl1          are respectivelyas defined in any one of claims 2 to 6;Y is selected from -CH2-, -CH2CH2-, -CH2OCH2-, or is absent;R14 and R15 are each independently selected from H and -C1-6 alkyl;Preferably,in thefragment, when M is C-R1, R1 is selected from halogen (preferably F or10Cl) or -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl substituted by halogen, more preferably -CF3), and M' is C-R1' and R1' is halogen (preferably F); or when M is N, M' is C-R1' and R1' is halogen (preferably F);in the       Rs     fragment, both M are C-R1, or one M is N and the other M is C-R1, R1 are15each independently selected from H, halogen (preferably F), and halogen-substituted -C1-6 alkyl (preferably -C1-3 alkyl substituted by one or more F, more preferably -CF3), preferably the M ortho to R3 is selected from N and C-R1 (preferably C-halogen, more preferably C-F), and the M ortho to R6 is C-R1 (preferably C-halogen-substituted -C1-3 alkyl, more preferably -C-CF3); R3 is selected from -NH2, -NHC1-6 alkyl, and N(C1-6 alkyl)2 (preferably selected from -NH2, -NHC1-3 alkyl, and N(C1-3 alkyl)2, more preferably -NH2); R5 is H or halogen (preferably F); R6 is selected from halogen(preferably Cl) and -C1-6 alkyl (preferably -C1-3 alkyl);r4sXa-XX R7"YR7'in the       v        fragment, R3 is selected from -NH2, -NHC1-6 alkyl, and N(Ci-6 alkyl)2(preferably selected from -NH2, -NHC1-3 alkyl, and N(Ci-3 alkyl)2, more preferably -NH2); R4 is selected from -CN, halogen, -NO2, and -C2-6 alkynyl substituted by halogen; V is selected from H, -C1-6 alkyl (preferably -C1-3 alkyl), and halogen; R7 and R7' are each H, or each are halogen, or one is H and the other is halogen or halogen-substituted C1-6 alkyl (preferably halogen-substituted -C1-3 alkyl), or one is halogen and the other is halogen-substituted C1-6 alkyl (preferably halogensubstituted -C1-3 alkyl), wherein the halogen is preferably F;Preferably, R3 is -NH2, R4 is -CN, V is H, R7 and R7' are each H, or one is H and the other is halogen (preferably F);R5i\R6QYrzrY1 R8’in the     w       fragment, R5 is H or halogen (preferably F); R6 is selected from halogen, -C2-6 alkynyl (preferably -C2.4 alkynyl), and -C1-6 alkyl (preferably -C1-3 alkyl); R8 and R8' are each H, or R8 and R8‘ are each halogen, or one of R8 and R8‘ is H and the other is selected from halogen, CN, and NO2, or one of R8 and R8‘ is H and the other is selected from -C1-6 alkyl optionally substituted by halogen, or one of R8 and R8‘ is selected from H, halogen, -NO2, CN, and -C1-6 alkyl optionally substituted by halogen, and the other is selected from -C1-6 alkyl optionally substituted by halogen; W is OH;Preferably, R5 is halogen (preferably F), R6 is selected from -C2-6 alkynyl (preferably -C2-4 alkynyl), R8 and R8' are each H, W is OH;X is selected from O and NH;Y is selected from -CH2CH2- and is absent;Z is selected from O;R9 and R10 are both H; or one or both are deuterium;R11 is -C1-6 alkyl (preferably -C1-3 alkyl), wherein the hydrogen atom is optionally replaced by one or more deuterium;R12 is selected from -C1-6 alkyl optionally substituted by halogen (preferably -C1-3 alkyl) and =C(Rd)2, wherein Rd is each independently selected from H and halogen (preferably F);m is 0, 1, or 2 (preferably 1 or 2);n and k are 0 or 1 (preferably 0);R13 is -Ci-6 alkyl (preferably -C1-3 alkyl, more preferably -CH3);R14 and R15 are H or -C1-3 alkyl (preferably -CH3).

9. The antibody-drug conjugate according to claim 1, wherein the Ras inhibitor compound is5 selected from:10N'°H       p37or stereoisomers,tautomers, stable isotopic5 variants, pharmaceutically acceptable salts, or solvates thereof.

10. The antibody-drug conjugate according to any one of claims 1 to 9, wherein the linker unit L has the structure:10wherein:(II-3)   or(II-5)Yi^, preferablyA is selected fromoand                H , wherein the end marked with * is connected to the drug P, and the N or Omarked with * is an atom from the drug P; Yi is each independently NH or O; R16 is H; R17 is H;S is selected from optionally present glucose, galactose, mannose, glucosamine, galactosamine, mannosamine, galacturonic acid, glucuronic acid, mannuronic acid, acetylgalactosamine, acetylglucosamine, acetylmannosamine, acetylgalactosaminuronic acid, acetylglucosaminuronic acid, acetylmannosaminuronic acid, glucosaminuronic acid, galactosaminuronic acid, mannosaminuronic acid; lactose, maltose, or their respective amino derivatives, acetamido derivatives, uronic acid derivatives, amino uronic acid derivatives, acetamido uronic acid derivatives; preferably S is selected from D-glucose, D-galactose, D-mannose, D-galacturonic acid, D-glucuronic acid, D-mannuronic acid, 2-acetamido-2-deoxy-D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-mannose, 2-acetamido-2-deoxy-D-galacturonic acid, 2-acetamido-2-deoxy-D-glucuronic acid, 2-acetamido-2-deoxy-D-mannuronic acid; D-lactose, D-maltose, D-sucrose, or their respective 2-acetamido and / or 6-carboxy derivatives;B is of formula (B-2): -(AA)d-, whereind is an integer from 2 to 12, preferably an integer from 2 to 4;AA is an amino acid selected from: alanine, glycine, asparagine, valine, phenylalanine, citrulline, glutamic acid; preferably -(AA)d- is the following polypeptide from C-terminus to N-terminus: Ala-Ala, Cit-Val, Ala-Val, Glu-Gly, Asn-Ala-Ala, Cit-Ala-Glu, Gly-Phe-Gly-Gly; wherein the N-terminus of the peptide is connected to the G part, and the C-terminus of the peptide is connected to the self-immolative linker A;G is selected fromandwherein the * endindicates the point of attachment to the antibody Ab, and the       end indicates the point ofattachment to B;Specifically, the linker unit L has the formula (II-3-1):(II-3-1)                                             (II-3-1’)and the corresponding general formula fragments where the maleimide moiety is0o     , wherein -O- in -O-S is O forming the glycosidic bond with the phenyl ring in thesolubilizing sugar unit, orSpecifically, when the solubilizing sugar unit S is absent, the linker unit L has the formula:5                            (II-4-1)                                             (II-4-1’)and the corresponding general formula fragments where the maleimide moiety is oo ; orthe linker unit L has the formula:(II-5-1), and the corresponding general formula fragments10owhere the maleimide moiety is         O11. The antibody-drug conjugate according to claim 10, wherein the solubilizing sugar unit in the linker unit is selected from:'^0 ^0H 0     1 OH OH    Glucose ^'0 J\ .'OH ° 1 ^^Aon OH OH     Galactose ^0 °Y>°H Y^^OH OH OH    Mannose ^0 ,xOH o y 0^J\ Y< y^oh OH OH D-glucuronic acid ' / '0 i      H Y\ 0      1       1 Y^OH OH OH 2-Acetamido-2-deoxy-D-glucose ^'0 । H Y\ .xN^ .0 0 y A 0^J\     । Y   oh OH OH 2-Acetamido-2-deoxy- D-glucuronic acid H 0       1         1 / y>°h OH OH 2-Acetamido-2-deoxy-D-galactose 'X? H / Y    .0 0 i Y pV^OH OH OH 2-Acetamido-2-deoxy- D-mannose YY H ° HO^'^Y^OH OH ^OH o^ y 1 OH HO Y HO^ HN. hAy” HO""" YY^OH OH Ra “Y^   OH 0— /   > OH Ra    0— / 0H oz T O   O I I J CO                                              1 1                                      ’ 1 °\ cu or Ra c / -S-N     OH 0— /   ) 0 Ra    0— / *—OH Ra e / i-N< *0H o— /   5 0 Ra    0— / *—OH Where Ra is H or C1-6 alkyl, e.g. methyl .'OH 0 1 <ytih OH 6 A '\0H ° 1 ^Y^OH OH OH Lactose ^0 .\0H o y Yy^oh OH 6 A H o y ^^OH OH OH Maltose y'9 H Y\ ,'IY / O 0       1        1 pV^o HO HO Y\ >\OH o y °Y / ^XY^*OH OH OH Maltose   derivative— acetamido         and carboxylic         acid derivative "9 H oY"Y° Y^Y^oh OH 0 <xOH o y Yy^oh OH OH Lactose    derivative— acetamido derivativewherein the wavy bond indicates the connection bond of the solubilizing sugar unit to the self-immolative linker A, the O attached is the O of the solubilizing sugar unit forming the glycosidic bond with the phenyl ring, and the dashed line at position 1 of the solubilizing sugar unit indicates that the configuration of the glycosidic bond can be a, P, or a mixture thereof.5        12. The antibody-drug conjugate according to any one of claims 10-11, wherein B in the linkerunit is selected from the following peptides:, wherein the left carbonyl group is connected to the self-immolative10linker A or the drug P, and the right N-terminus is connected to the G part.

13. The antibody-drug conjugate according to claim 1, wherein the [P-L] conjugation fragment has any one of the following general formulas:(III-A-1)(III-A-2)(AA)dJ---(CH2),.5---NHR11(III-A-1’)(III-A-2’)R11[B-G]>(III-B-2)(III-B-1)(III-B-1’)(III-B-2’)0and the corresponding general formula fragments where the maleimide moiety is         Oor a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein5         M, M', Ra, R3, R4, R5, R6, R7, R7', R8, R«', R9, Rio, R11, R12, R13, W, V, m, and the respectivestructural fragments in the drug P unit have the meanings defined in the corresponding claims 2-9, and A, S, B, G, AA, d in the linker unit L have the meanings defined in the corresponding claims 1012;the wavy line indicates the point of attachment to Ab; the atom marked with * is the attachment 10 site in the drug P unit for connection to the linker unit.

14. The antibody-drug conjugate according to claim 1, having any one of the following general formulas:15(X1-A-1)                                 (X1-A-2)(X1-A-1’)(X1-A-2’)(X1-B-1)                               (X1-B-2)(X1-B-1’)(X1-B-2’)0and the corresponding conjugates where the maleimide moiety is         Oor a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof, wherein:10M, M', Ra, R3, R4, R5, R6, R7, R7', R8, R8', R9, R10, R11, R12, R13, W, V, m, and the respective structural fragments in the drug P unit have the meanings defined in the corresponding claims 2-9, and A, S, B, G, AA, d in the linker unit L have the meanings defined in the corresponding claims 1012;the atom marked with * is the attachment site in the drug P unit for connection to the linker unit;q is an integer or non-integer from 1 to 10, or a range formed by any two values between 1 and 10; preferably q is from 1 to 8, or an average DAR value in a range formed by any two values between 1 and 8.

15. The antibody-drug conjugate according to any one of claims 1 to 9, wherein the linker unit L has the structure of formula (II’-3):wherein,J is selected from -J1-, -J2-, -J1-J2-, -J2-J1-, wherein-J1- is selected fromwherein the * indicatesthe point of attachment to drug P or to -J2-, and the wavy line indicates the point of attachment to the cleavable linker B;-J2- is selected fromRis         , wherein the * indicates the point of attachment to drugP or to -J1-, and the wavy line indicates the point of attachment to the cleavable linker B;each occurrence of X' is independently selected from CH or N;each occurrence of Y1' is independently selected from -NH-, -NC1-6 alkyl-, or -O-;each occurrence of R16‘ is independently selected from H and -C1-6 alkyl, preferably H or C1-3 alkyl, more preferably H;each occurrence of R17' is independently selected from H, -NO2, -NH2, -CF3, or a moiety of formula (A1):       ' p U;each occurrence of R18 is independently selected from -C1-6 alkyl, preferably C1-3 alkyl, more preferably methyl;T is selected from -C(Ra)2-, -O-, -NRa-, or is absent;T1 is selected from -C(Ra)2-, -O-, -NRa-;T2 is selected from -CRa- and -N-;T3 is a peptide of 2~6 amino acids linked via the carboxyl terminus to N;Q is selected from -CO-, -O-, -NRa-, or is absent;U is selected from glycosyl or a derivative thereof,the subunit, and a hydrophilic peptide comprisingO RO Ris selected from natural amino acid residues and unnatural aminoacid residues;Ra is each independently selected from H or -C1-6 alkyl, preferably H or -CH3;p is an integer from 0 to 4, for example 0-2, 1-4, 1-2, 2-4;t is an integer from 0 to 10, for example 0-8, 0-6, 0-4, 0-2, 1~10, 2~10, 2~8, 2~6, 2~4, 6~10, 8~10;B is of formula (B-2): -(AA)d-, wherein d is an integer from 2 to 12, preferably an integer from 2 to 4, preferably -(AA)d- is the following polypeptide from C-terminus to N-terminus: Ala-Ala, Cit-Val, Ala-Val, Glu-Gly, Asn-Ala-Ala, Cit-Ala-Glu, Gly-Phe-Gly-Gly, wherein the N-terminus of the peptide is connected to the G part of the linker unit, and the C-terminus of the peptide is connected to J;G is■G1N—G3'(Bu)orwherein Gi is the atom inAb responsible for attachment to L, G3' is -C1-10 alkylene-, preferably -C1-5 alkylene-, Bu is absent oris a structural fragment of formula (A), wherein T0 is -C1-6 alkylene-, preferably-C1-2 alkylene-, more preferably methylene, and p, Q, U are each as defined above.

16. The antibody-drug conjugate according to claim 15, wherein J is selected from:^18(J-3) or*X’(J-4);(J-6) or(J-11)(J-6’);(J-14)R189 Rib'(J-15)(J-16)(J-16’)rib            (J-17)(J-18)(J-20)(J-24)(J-25)wherein the * indicates the point of attachment to drug P, and the wavy line indicates the point of attachment to the remainder of the linker unit;each occurrence of X' is independently selected from -N- or -CH-;each occurrence of Yi' is independently selected from -NH- or -O-; wherein the Yi' attached to the six-membered aromatic ring is attached para or ortho to the other attachment point of the ring;each occurrence of R16' is independently selected from H or C1-3 alkyl, preferably H;each occurrence of R17' is independently selected from H or a fragment of formula (A1)each occurrence of R18 is independently selected from -C1-3 alkyl, preferably methyl;each occurrence of T is selected from -O-, -NRa-, or is absent;each occurrence of T1 is selected from -CH2-, -O-, -NCH3-;each occurrence of T2 is selected as -N-;each occurrence of T3 is a 2-4 peptide linked via the carboxyl terminus to N, selected from AlaAla, Cit-Val, Ala-Val, Glu-Gly, Asn-Ala-Ala, Cit-Ala-Glu, Gly-Phe-Gly-Gly;each occurrence of Q is absent or is -NRa- or -O-;0each occurrence of U is selected from* , a hydrophilic peptide such as, or a glycosyl (preferably a monosaccharide or disaccharide or uronic acidthereof) or derivative thereof, preferably a hydrophilic peptide, wherein t is 2-14, such as 4-14, 6-12, preferably 10;each occurrence of p is 0-4, preferably 0-2;For example, the self-immolative linker J is selected from:A-a ’ Il N-U I                            ■ 0 aoh o y °\ ^0H OH 6h H rr^ ■ YY Ar 1 A °      °'-A\                   0 । r j8 , Rl8                       Rl8                       | 18 I -■ : ■ j.....w.........x A                              L        Jl° Ay           , 0 .A0^yy o 5 o . Y .Z     0 Uax o .A-^vy o A IXoA^ 1^0 , H Y *        O ^-U. JJ 0    OH QH a     0.    Jk    A AH u     xz   \a H i i OH OH                        , H                                         ^18 / A                    । r ii                          / A o I J                 H I ।    ni i]     *AA CL           A _N.                      II      J l'              \ 1L    M ,      YA , A>........ / ,‘4 - ° Ra                             i, r i L Jl°         \ A        -A Y  N" \ II I O     Ra ,                         L            Jl0 , .......uY . lV a I I L         J10 , O ■Ayy o AX Uan1 0                                            I .Ya ° 'N / XXa^ Ian\ , 0 zVy\ o <V UY. o Jl I । L         J10 ,A.....a n •A-A Ax> 1 fl N 0 A. IJ ? A\ T. o Xj ' / TP HN\^\ jJO AX o Y  N Y 5                  ° 5                          L         J10     .

17. The antibody-drug o W             o *—II c j      N (CH2)-|.5---- O 0 *            y___ N । (Cl 12)0-4 To AA1 X T< ^Q' ' . .....k........cl-j A . i JL                            L A TA >r n                                                      >r n I I                                                                        J । L         J1°           ,                                                             L Jl0           , X 'Y o^ II             L              J8 O , ■    0                0 WuA 1 _ " * J 4.    • “Ai ? A J1—0 ^N.h ,                                                                                                            , H rr^ 4                                                                                                                                                    \              \ n A        / N\                 N X J -A . j.i................: MrA   ^"A-X A       I ,                           L           J10                 ,                          L          J10            , conjugate according to claim 15 or 16, wherein G is 0 0 A        HN--G3'(Bu)—|- 0 ,                                                                                                                                                                       , 0 II                                 0 0                                                                  II s Ll      / Gl"|    h— (CH2)0-4^ A_--0H To AA A / U              A      tA / [Tq^ or               0                      , wherein To is -C1-4alkylene- (e.g., -C1-2 alkylene-, such as methylene), T is absent or is -C(Ra)2-, p is 0-4 (e.g., 0-2) and Q is selected from -O- or -NRa-, and U is selected from a uronic acid (preferably a uronic acid of a0'monosaccharide or disaccharide) or derivative thereof linked via a carbonyl group,       L       Jt ,O RaO; or wherein To is -C1-4o"Jt , a hydrophilic peptide such asalkylene- (e.g., -C1-2 alkylene-, such as methylene), T is absent or is -C(Ra)2-, p is 0-4 (e.g., 0-2) andQ is -CO-, U is selected from an amino sugar (preferably an amino monosaccharide or aminodisaccharide) or derivative thereof linked via an amino group,* , or a hydrophilicRa O _       _ Rapeptide such as; or wherein To is -C1-4 alkylene- (e.g., -C1-2 alkylene-, such asmethylene), T is selected from -C(Ra)2-, -O-, -NRa-, or is absent, Q is absent, p is 0-4 (e.g., 0-2, 1-2), and U is selected from a glycosyl (preferably a monosaccharide or disaccharide) or derivative thereof linked via a glycosidic bond, or an amino sugar (preferably an amino monosaccharide or amino disaccharide) or derivative thereof linked via an amino group; wherein t is an integer from 1~20, e.g.,2-10, 2-8, 2-6, 2-4, 4-10, 4-14, 6-10, 6-12, 8-10, 8-14.

18. The antibody-drug conjugate according to any one of claims 15-17, wherein B is as defined in claim 12, and / orO     RII                       I /    QUthe subunit     R’           of the hydrophilic peptide corresponds to a residue of arginine,serine, threonine, tyrosine, cysteine, aspartic acid, asparagine, glutamic acid, glutamine, lysine, histidine, glycine, tryptophan, ornithine, citrulline, sarcosine, or R, R', R” are each independently additionally a group containing carboxyl, sulfonic acid, phosphate, amino, amido, quaternary ammonium, mercapto, and / or hydroxyl;preferably the hydrophilic peptide comprises 4-14 units of polysarcosine, polyarginine, or polyglycine, preferably 6-12 units of polysarcosine.

19. The antibody-drug conjugate according to any one of claims 1-9 and 15-18, wherein the linker unit has the formula:(II’-3’-1)(II’-3’-2)(II’-3’-3)(II’-3’-4)(II’-3’-5)For example, the linker unit L is selected from the structural fragments shown in Table 7 of the specification.

20. The antibody-drug conjugate according to claim 1, wherein the [P-L] conjugation fragment 5 has any one of the following general formulas:[P-J-B-G]—|—5 III'-1, wherein the -J-B-G- fragment is as defined in any one of claims 15-19, preferably as defined in claim 19, and the drug P unit is a Ras inhibitor compound as defined in any one of claims 1 to 9, preferably a Ras inhibitor compound as defined in claim 7 or 9, or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof;Preferably, the [P-L] conjugation fragment is a conjugation fragment as shown in Table 8-1 of the specification.

21. The antibody-drug conjugate according to claim 1, having a formula selected from:P---[J-B-G]--Abq (X2’),wherein the -J-B-G- fragment is as defined in any one of claims 15-19, preferably as defined in claim 19;the drug P unit is a Ras inhibitor compound as defined in any one of claims 1 to 9, preferably a Ras inhibitor compound as defined in claim 7 or 9, or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof;q is from 1 to 10, or an average DAR value in a range formed by any two values between 1 and 10, for example about 1-10, 1-8, 2-8, 3-10, 3-8, 4-10, 4-8, 6-8, or 6-10.

22. The antibody-drug conjugate according to any one of claims 1 to 21, wherein Ab is an antibody or antigen-binding fragment that binds to a tumor-specific antigen or tumor-associated antigen, wherein the tumor-specific antigen or tumor-associated antigen is selected from: HER2, Her3, HER1 (ErbB1), HER4 (ErbB4), TROP2, Nectin-4, tissue factor, PD-L1, PD-1, PD-L1 / PD-L2, MET, CLDN18.2, KIT, CTLA-4, RPR1, ephrin A2 receptor (EphA2), folate receptor (FRa), mesothelin, endothelin receptor, GCPII, IL-13Ra, BCMA, GD2, CLL-1, CA-IX, MUC1, 5T4, AOC3, ALK, AXL, C242, CA-125, CCL11, CCR5, CD2, CD3, CD4, CDS, CD15, CA15-3, CD16, CD18, CD19, CD20, CD21, CD22, CD25, CD30, CD32, CD33, CD37, CD38, CD44, CD52, CD56, CD64, CD66e, CD70, CD72, CD74, CD79a, CD79b, CD123, CD138, CD142, CD174, CD276, CDH3, CCD79b, CLDN9 / CLDN6, CA19-9, DPEP3, AGS-16, IGF1R, IGF2R, VEGFR1, VEGFR2, VEGFR3, PDGFR-a, PDGFR-p, EGFR, EGFRvIII, ENPP3, FcRH5, FRa, KAAG1, LIV-1, Mesothelin, cMet, ROR1, SLTRK6, TF, BMPR1B, E16, TOP1, STEAP1, 0772P, MUC16, Napi3b, Sema 5b, PSCA hIg, ETBR, RNF124, prostate cancer-associated gene 1, TrpM4, teratocarcinoma-derived growth factor 1, C3DR, FcRH2, NCA, MDP, IL20R-a, Brevican, EphB2R, ASLG659, prostate stem cell antigen precursor, GEDA, BAFF-R, CXCR5, HLA-DOB, P2X5, LY64, FcRH1, IRTA2, TENB2, integrin a5p6, integrin a4p7, FGF2, FGFR1, FGFR2, FGFR3, FGFR4, PSMA, Somatostatin receptor, RANK, SLAMF7, ITGB6, CEACAM5, CA9, EGFRvlll, IL2RA, AXL receptor tyrosine kinase, TGF-pR, TNFRSF8, cancer / testis-associated antigens, CLEC14A, GRP78, stem cell-specific antigens, ASG-5, PRR4, GUCY2C, SLC39A6, TPBG, tumor-associated antigen CA242, FOLR1, GPNMB, HAVCR1, prostate tumor target Mindin, VTCN1, PTK7 protein tyrosine kinase 7, macrophage stimulating 1 receptor, TACSTD2, CA6, DLL3, DLL4, EpCAM, FAP, DKK-1, Endoglin, VCAM1, GPC3, DR5, ASCT2, B7H1, B7H3, B7H4, or any combination thereof;Preferably, the tumor-specific antigen or tumor-associated antigen is selected from AXL, B7H1, B7H3, B7H4, BCMA, CD16, CD19, CD22, CD25, CD30, CD32, CD33, CD44, CD64, CD70, CD74, CD79, CD138, CD142, CD276, CDH3, CEACAM5, Claudin 18.2, CLDN9 / CLDN6, DPEP3, EGFR, ENPP3, EphA, FcRH5, FOLR1, FRa, GCPII, HER2, HER3, KAAG1, KIT, LIV-1, Mesothelin,cMet, MUC1, Nectin-4, PD-L1, PD-L1 / PD-L2, PSMA, ROR1, RPR1, TF, TOP1, TROP2, or any combination thereof;More preferably, the tumor-specific antigen or tumor-associated antigen is selected from HER2, Claudin 18.2, EGFR, TROP2, Nectin-4, or a combination of EGFR and Met.

23. The antibody-drug conjugate according to any one of claims 1 to 22, wherein:The Ab comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR) that specifically bind to HER2, wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 6,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 7,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 8,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 3,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 4, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 5;or the Ab comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR) that specifically bind to Trop2, wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 18,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 19,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 20,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 15,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 16, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 17;or the Ab comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR) that specifically bind to Claudin18.2, wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 29,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 30,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 31,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 26,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 27, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 28;or the Ab comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR) that specifically bind to EGFR, wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 40,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 41,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 42,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 37,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 38, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 39;or the Ab comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR) that specifically bind to Nectin4, wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 72,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 73,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 74,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 69,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 70, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 71,or the Ab comprises a first set of complementarity determining regions that specifically bind EGFR and a second set of complementarity determining regions that specifically bind MET, wherein,the first set of complementarity determining regions comprises 3 heavy chain complementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 49,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 50,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 51,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 52,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 53, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 54,the second set of complementarity determining regions comprises 3 heavy chaincomplementarity determining regions (HCDR) and 3 light chain complementarity determining regions (LCDR), wherein: according to Kabat definition,HCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 55,HCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 56,HCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 57,LCDR1 comprises or consists of the amino acid sequence of SEQ ID NO: 58,LCDR2 comprises or consists of the amino acid sequence of SEQ ID NO: 59, andLCDR3 comprises or consists of the amino acid sequence of SEQ ID NO: 60.

24. The antibody-drug conjugate according to any one of claims 1 to 22, wherein the Ab comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 10, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 9; orwherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 22, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 21; orwherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 33, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 32; orwherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 44, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 43; orwherein the heavy chain variable region comprises the amino acid sequence described in SEQ ID NO: 76, and wherein the light chain variable region comprises the amino acid sequence shown in SEQ ID NO: 75; orwherein the Ab comprises a first heavy chain variable region and a first light chain variable region, and a second heavy chain variable region and a second light chain variable region, wherein the first heavy chain variable region and first light chain variable region respectively comprise the amino acid sequences described in SEQ ID NO: 61 and SEQ ID NO: 62, and wherein the second heavy chain variable region and second light chain variable region respectively comprise the amino acid sequences described in SEQ ID NO: 63 and SEQ ID NO: 64.

25. The antibody-drug conjugate according to any one of claims 1 to 22, wherein the Ab comprises:(a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 2, and(b) a light chain comprising the amino acid sequence of SEQ ID NO: 1;or(a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 14, and(b) a light chain comprising the amino acid sequence of SEQ ID NO: 13;or(a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 25, and(b) a light chain comprising the amino acid sequence of SEQ ID NO: 24;or(a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 36, and(b) a light chain comprising the amino acid sequence of SEQ ID NO: 35;or(a) a heavy chain comprising the amino acid sequence of SEQ ID NO: 76, and(b) a light chain comprising the amino acid sequence of SEQ ID NO: 75,or(a) a first heavy chain comprising the amino acid sequence of SEQ ID NO: 45,(b) a first light chain comprising the amino acid sequence of SEQ ID NO: 46,(c) a second heavy chain comprising the amino acid sequence of SEQ ID NO: 47, and(d) a second light chain comprising the amino acid sequence of SEQ ID NO: 48.

26. The antibody-drug conjugate according to any one of claims 1 to 22, wherein the Ab is selected from Trastuzumab or an antibody fragment thereof, or another anti-human HER2 antibody that recognizes the same epitope or competitively binds to human HER2, preferably Trastuzumab; orwherein the Ab is selected from Sacituzumab or an antibody fragment thereof, or another antihuman TROP2 antibody that recognizes the same epitope or competitively binds to human TROP2, preferably Sacituzumab; orwherein the Ab is selected from Zolbetuximab or an antibody fragment thereof, or another antihuman Claudin18.2 antibody that recognizes the same epitope or competitively binds to human Claudin18.2, preferably Zolbetuximab; orwherein the Ab is selected from Cetuximab or an antibody fragment thereof, or another antihuman EGFR antibody that recognizes the same epitope or competitively binds to human EGFR, preferably Cetuximab; orwherein the Ab is selected from Enfortumab or an antibody fragment thereof, or another antihuman Nectin4 antibody that recognizes the same epitope or competitively binds to human Nectin4, preferably Enfortumab; orwherein the Ab is selected from Amivantamab or an antibody fragment thereof, or another antihuman EGFR and MET antibody that recognizes the same epitope or competitively binds to human EGFR and MET, preferably Amivantamab.

27. An antibody-drug conjugate selected from:ADC-1 o / o=\ ZI .....v= IZ zz    t .,,,. /             6 o >=o    < Y ■ Q o / Y y° fy ° oY o                       «. Her2 ADC-2 h2noc.                             o. IT         h : ? H ? ° yy X^yO^J O H * 0 H        y \     F                         ADC-2                         / -Her2 ADC-3 / Y       x h2noc                           0. IX          h " ? H ° o nay yyn'Y XNyO^iy o H 1 o H         Q \^F                 ADC-3                / ^-Her2 ADC-4 / 'Y         ' mYA^^^        H2NOC.                    °x f 1                H ° H ! 9        Y Yn^ny   ytny^n ^'tn'Y 4Y AYoju s h i s h \    )                       ADC-4                       X V-Her2ADC-5 HpNOC                           O. J!               H ° H °       YA O-NAN^ VcY 0r-° r r r" / \ F                            ADC-5                           / / -Her2 ADC-6 G>h2              \ /       ra CN y rCF3 nA         h2noc„                o h 1                  h ? V h ? 9         T> ° D NA <1 Yc.n^Ad   ^NyO.^   O H i 0 H         0, \      J                      ADC-6                     4 ^-Her2 ADC-7 - nYm             H2NOC. „ N N             2 i 0 -0        V^\ A?Vyf YrY-A^A > .. -Her2 ADC-8 - nY-m               H2NOC. N N                     -0 A?Vtf YaVA-A \HNY^NYyYJ 5 h t S h      y \                         ADC-8                     / -Her2ADC-9ADC-10ADC-11ADC-12ADC-13 H2NOC                           0- Y]             H " 9 H i 9      Y\- X      y Y°-Uq o H i O H       O \ YY         0       A lSNHAc \ f y„ / \                          OH OH                 ADC-13         / q -Her2 ADC-14 h2noc.

0. IT         H " 9 H = O     YX oYY  cYnY'^ VO; Y       "     / \                         OH OH               ADC-14         / q -Her2 ADC-15 <7^° / / z O ) oJ            § ZI                < .....X IZ 0=(^ / ZI TITI / 1" /     o o o o ° XO / --(      / --( T z iz o—< V'io—<   )—o *  % °Y o Yz <Y° PxY: o Xz=< ................A‘............... VHer2 ADC-16 / \ xxy                \ Y^yy                    ' Y Y Tjn h2noc                           0. 11            H    H H E H       Y yNy^Xyo H T o H o      oy,.oh F       YA \                                             OH \                             OH 6 \                       °^y'OH                      / \              YvYoh               / \                         OH OH                ADC-16       y / YHer2 0ADC-17 A o \ <4            £ zz                < ..... IZ ZT  < / TITI / "'■<      z   O    O   O O               / ---(       ' / ---( -r O '       /  \      /  \ I Z TZ   OA  V'lO—<   >—O £   °4 o A ^>o Af O V............. \\-Her2 0 ADC-18 /          H2NOC                         0- fl°        H " 9 H i 9     YA oAn^n^ hA1 Any°^X9o h o H       °y \A ° AC \                          OH OH               ADC-18          / q -Her2 ADC-19 m'-J' . A /           H2NOC                            0- T^O          H " 9 H = 9      T\ z r A AJ     ) \                         OH 6h              ADC-19         / / -Her2 ADC-20 ii         0                   h ? 9 h                    ° oAAa  ^ynAn K / A A¥o^yJ o H o   oXA V A \                      OH OH               ADC-20         / q Her2ADC-21 / HOm          \ JI        °                 H ?   ? H                  O 0 NAN^] h J s......?1.....1!............... \                      OH OH                ADC-21       / q ADC-22 / > : Ji JI                         H          II H                     9 yJ.  Xy ju o h X o Yy \     p                        ADC-22                    J ADC-23 / \ X II                   \ /       M-Jf        h2nto           \ F N                          rNH                       i N                                             c> II 1                            H ? V H                       O \            --0 y0-'^    ° H °      o^y / Her2 \                                  ADC-23                    / q ADC-24 / HOxn              \ UJ<Yy         h2n^o           \ /        j N                  rNH                \ 0               H ? 9 H                O O H JL 0      o^yHer2 \                           ADC-24                    JADC-25 M . ^=z   71     o .MW xP o O >       ZI o oM K      h"\ TZ    '--<    Z \   )=O V< x Xo '   ZT / Z -Her2 ADC-26 H2N^.O               \ F^Pm                   / NH               । T ?              r H       9 H                0 [TVN'^ PnQ<              o h >,o    oA / / \     F                         ADC-26                        / / -Her2 ADC-27 /       ClF YNH2                     \ yp          h2n^o          \ CN             J"              \ Jl YCF3                 1 N f                   / n J! A                   H - h H                9 D 9 N      fVYN KnWd 'U^ / J 0 H 0   Q.W / \ YO   0 \       F                      ADC-27                     4 Her2 ADC-28 /    HOX                            \ /      PPyXF         h2n^0           \ F-^                     , NH                 \ T ?              r JI                                   H ? H H                         / 9 \   ? N      crN^NMN9^^^NW o h      o \ LYF     0 \     F                         ADC-28                       / / Her2 ADC-29 /    HOx^X^\                                   \ Yj J I                 H      9 H      9 H              p oAAx  pyNY^YN^A^N'p^^X -f- ■- '■ j! ' •' \     p                        ADC-29                                   / qADC-31ADC-32ADC-33ADC-34ADC-36ADC-37ADC-38ADC-39 / H0^                              \ Xxf                \ /      AAFF                      \ A A                             \ Fi nVc     H2N0A o   - o    °V\ 11   [                      LI = H H ?    ||             T Aegfr 1    o A nA    AA       A^^nF- / \^^n W AYAU A । A   o \                0 \      F                             ADC-39                          / q ADC-40 N A<\A           - n II J                           H :    9 H                      P ANQ>                 O h o     qFFTEGFR A  ’Jz \                      OH OH               ADC-40        / q ADC-41 kXi FxJ^ ?F'           i " ' ! 0 n nA    AANY^'n'T NA^n'A^'0'^ w AyAJA " ‘ s H AA\A       0      A .'OH T                  o y F        aj A A   OH —                        OH OH            ADC-41    — H              9 r^^FFL^ 0      F-V 0 2                         / q ADC-42 i        a^o            । °A ■F IZ °F . . zi      q o z TZ o—    oA __ p o >° <A J° A      . FaF'     § 8 Fz=<z O—y ? VLL- 1______________aZ__________1 -Her2 qADC-44ADC-45ADC-46ADC-47 CY_ 0 ■Her2 q / Y ^CONH2 1           0                             1     •    0 u -    0 AyAYY o [VAV^ YY1 kYV s h t o h N^N                  1 Y --N,-'              ADC-47 ADC-48 o4 "Y IZ CM       \   - i°Y O   ZI '.....Y vO ° \ z—A z —O Vz y3ya 0 -Her2 — r l|^F .hk J ADC-48 q ADC-49 Yy ..F Y^                      xconh2 1           0                             I ;    0 H :    0 0.__ Ho'AA'"- AYAYiArA"n V ADC-49 0 Her2 ADC-50 — ^.CONIY Ox A F^ Y <Y               । Y YY Yi N i n N 1        o                        0 H        ° H YY9 Y50 NyN 0 -Her2 — <Y' ADC-50 q ADC-51 .-Y^ ^ / F Y^                            ,,,conh2 Ox fl HO"^^ F" 0 -VaVv YY"^ ^aYi m t ° N^N            H YY         ho F                            H0V hoJ ADC-51 'YYh HN V^o ■^OH 'OH — er2ADC-52 ho^, xxi AA'p F, A A n mA A, /        H2NOC „       „ 0,, Xi              h : 9 h : 9 'z 0 X'N A> -nA   'AV^A S h 1 S h 0 IX /      o   cr ]                    > 0 OH OH F _          ADC-52               1 OH OH                _ -Her2 q ADC-53 1                                   /                                                    1 -n— / '' O ■" A ^71 _ / ° >  Mm / A A / A / w      \X? ° \ A_A oA          T1 o A A? ~Z.—     IZ A A° — Z       ZI 2=0  o=^ IZ n z \ 1        °^A        1 -Her2 J q ADC-54 1                           /                                              1 / —z -n— / '   O ■"                T' O >                / \ X A °             )—(\ / )—C x> o=(        A O -A°^i O     IZ T -A O        ZI co IZ >° . °x , -Her2 q ADC-55 ,, F                       / CONH2           o 1     N H : ? vy Axe'ii" ’' • ’ 0 N-yN V F l[T _       A~A              ADC-55          _ Her2 qADC-56 1                                                                                                                                                                          ' IZ                      CO ~     \ -                         “? 5                     o n °=\                Q o   \                    < o zi ......V zvO / z \L / > |_______________x_________________________________| -Her2 q ADC-57 ^.F AJA                    / conh2      o C'P      1      0                 1   :  0 u -  0 V7 pAC-A   IJVN1 S H T I H 0 nYn ¥ _       A / '                ADC-57                   _ -Her2 q ADC-58 1                                    5                 1 \ o— ' '          Z—c v° o p >° ? Ch on           z / U co          / z A.....\ IZ   o >o2 , /    I ZI A ,        o£  , -Her2 q ADC-59 ^x^F A^^ A                                ^CONHj         0 hoAAAa a-A'Y'ii o pAnA"A^A fAv^ ^a-V "A H 0 N^N                 C aI      ,-Nl / T                                n           n F                                0    1         0 rr^F J L                                    ADC-59                         _| -Her2 q ADC-60 °A ZI . / ” TZ     ' O ' 8°n O   ZI   o '.....A A V   V       ° —Z    / —Z          <D \—(  \       d \   /         Q < °A o ■ o K Qy^-।_____I?_________________। -Her2 qADC-61 CXX AC F\ A A fy n-^v       h2nh°c> o H ? o°vv oFAa   F"? / N|F'X       X A^O^X 0 H * 0 M ° Y / Fv      o                  NH hovXh HO'Xoh _                        ADC-61       HO"           _ -Her2 q ADC-62 —      HO                                       - XXX F f A A Xi mAA         h2noc „       „ A^s N A 0          u    0 u - 0 AV o-XXN^  FrVAVAX o h o o hhnx ° ]                                  N V --^ o F                                                   1 0 _                               ADC-62       L     Jg           _ -Her2 q ADC-63 “    HO^                        “ XXX ~aFf f. A A Ai nXAa      H2Nh°f o h . oX oanXn^ Xnt°^X o H o hhnX ° X^Xs^x-F          o                  J     l0 X, 1                                                                0 F _                             ADC-63              8           _ -Her2 q ADC-64 XXX l'" \F F^ A A Fi »AA /       H?NOC n A o"         A    o     . o Va oanXn-. ^v^Xy^XXy W XV O s H ‘ s 0 ^XvF OH 0H° O <°          HO V F HO^I^A^J        hoA OH OH 1                HAF'r,u L                         ADC-64             OH      _ -Her2 qADC-65ADC-66ADC-67ADC-68ADC-69ADC-75 ,      ? 'C 1    A            / A Cl CF3 O""Yf N 0     >   0   < > U-Z A! A>=\ N h2n     f nA                           1 n—. .                            . [1 H rN-A^ )L „ 1 hn : 9 H > Ho\° 1           0 5 :     0 cr"7 — Her2 q f^O^ _             F              ADC-75                        _ ADC-76 .            0                                    1 1  A       A ci cf3 oYn o Z Z o < AAAzZ    a y>=Yn       Y- h2n      f n={      f                       ( o-y z / F N—' _              — /          ADC-76 [1 H □ L     „ 1 H^ : 9 H iT-nAy ° HoT, / A-nAy D 1           0 J5 A0 :     0 ^N-Y 0 - -Her2 - q ADC-77 ,          °                                1 J    A              / N. ci cf3        n o Yh  9  ii AA Yz-z CVAi hhn      Yn-t h2n f nA                           J °YAF __ / N            ADC-77 [1 H f^NA „ 1 HN ? 9 H ; <9 An^y 1 0 J5 Y --Her2 J q ADC-78 r                   u ? cr            ». o' hhnC ■ Z'.....CaA<A nh2     o                     n   y        n ,N=V / An           1° '    1? CAAb ( JL vo^Y Y T ci / AA A-A ]          ADC-95 _      ^AAA 5 0 'N^\_ Her2ADC-79 °Y o X .__+ .-                 CD A'-Z't.          h- u-—-< 1 /          d V-Y-- /        q / ----\ JI J. LL. ।____________________________________________________________________________________________________________________________________________________। [1 H ■nJ'n / -A" h n -nAa. 1 j J5 J^N 0 J- 0x D 0 -Her2 ■X ADC-80 XqJ^w^YVX o=( H      y— / ' J J                   f N-N 0- /        N (  >-\<       °x _       -- 0                  ADC-80 0L         1 1      -     0 0     1 A HN. J5 H : o 11 0 V 0 J5 A Her2 — q ADC-81 ff_XXs ° ,.                   a x" N—\ OHf )=^ CF3        ^^0 (  >— /  N=(                      J / N \— / ''       N—J p _°Ya "r N— __                 /                   ADC-81 4Ur 0L         1 H : 9 H rj 0     1 d N. J5 : 0 J- 3 TR0P2 q ADC-82 r° r°‘ >°' —z XJ °A o o     » <                  § o °A ZI / ~o « OQ) XT r n zvz ) O T       o r ■ I____________________________________________________________________________________________1_________________________________________________________________________________________________________________________________________________I "n^yY H 1 J ? n Y^V 1           0 J5 ’1 / 0 -Claudin 18.2 q ADC-83 rp—XXs °            । YCYAax a x" oA )= / CF3           '  0  N"^ ( X—1 nA >»                   A-n 3— / '-       n-A F -ovJa A" N— _               /                  ADC-83 4ar oL 1 ? H rX o 1 d N. J5 : 0 cY- 0 EGFR qADC-88ADC-89ADC-90ADC-91Her2ADC-91Preferably,the antibody indicated as Her2 is specifically Trastuzumab;the antibody indicated as CL18.2 is specifically Zolbetuximab;the antibody indicated as TROP2 is specifically Sacituzumab;the antibody indicated as EGFR is specifically Cetuximab;the antibody indicated as EGFR-Met is specifically Amivantamab;the antibody indicated as Nectin-4 is specifically Enfortumab;q represents 1 to 20, for example 1-10, 1-8, 2-8, 3-10, 3-8, 4-10, 4-8, 6-8, or 6-10;or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof;preferably the antibody-drug conjugate of Examples 1-94, or a stereoisomer, tautomer, stable isotopic variant, pharmaceutically acceptable salt, or solvate thereof.

28. A pharmaceutical composition comprising the antibody-drug conjugate according to any one of claims 1-27 and one or more pharmaceutically acceptable excipients.

29. The pharmaceutical composition according to claim 28, for administration intravenously, intratumorally, subcutaneously, intramuscularly, orally, intranasally, intrathecally, transdermally, or topically, preferably for administration intravenously, intraperitoneally, subcutaneously, or intramuscularly.

30. The antibody-drug conjugate according to any one of claims 1-27 or the pharmaceutical composition according to claim 28 or 29, for use in treating or preventing a disease mediated by a Ras mutant protein, such as a KRas mutant protein, specifically a KRas G12D mutant protein, preferably for use in treating or preventing a hyperproliferative disease, more preferably for use in treating or preventing a tumor.

31. Use of the antibody-drug conjugate according to any one of claims 1-27 or the pharmaceutical composition according to claim 28 or 29 in treating or preventing a disease mediated by a Ras mutant protein, such as a KRas mutant protein, specifically a KRas G12D mutant protein, preferably a hyperproliferative disease, more preferably a tumor.

32. Use of the antibody-drug conjugate according to any one of claims 1-27 or the pharmaceutical composition according to claim 28 or 29 in the manufacture of a medicament for treating or preventing a disease mediated by a Ras mutant protein, such as a KRas mutant protein, specifically a KRas G12D mutant protein, preferably a hyperproliferative disease, more preferably a tumor.

33. A method for treating or preventing a disease mediated by a Ras mutant protein, such as a KRas mutant protein, specifically a KRas G12D mutant protein, preferably a hyperproliferative disease, more preferably a tumor, comprising administering to a human or animal the antibody-drugconjugate according to any one of claims 1-27 or the pharmaceutical composition according to claim 28 or 29.

34. The antibody-drug conjugate or pharmaceutical composition according to claim 30, the use according to claim 31 or 32, or the method according to claim 33, wherein the hyperproliferative disease or tumor includes solid tumors and hematological tumors, and all precancerous cells and cancer cells and tissues, selected from lung adenocarcinoma, lung cancer (including squamous cell carcinoma and non-small cell lung cancer, small cell lung cancer), bone cancer, pancreatic cancer, pancreatic ductal adenocarcinoma, skin cancer, head and neck cancer (including head and neck squamous cell carcinoma), melanoma (including cutaneous or intraocular melanoma), squamous cell carcinoma, anal region cancer, testicular cancer, urethral cancer, ureteral cancer, penile cancer, prostate cancer (including hormone-refractory prostate cancer), bladder cancer, uterine cancer, ovarian cancer, ovarian epithelial cancer, fallopian tube cancer, endometrial cancer, cervical cancer, vaginal cancer, vulvar cancer, gastric cancer, gastric adenocarcinoma, colon cancer, rectal cancer, colorectal cancer, liver cancer, breast cancer (including metastatic breast cancer, triple-negative breast cancer (TNBC)), esophageal cancer, small intestine cancer, lip cancer, laryngeal cancer, nasopharyngeal cancer, oral cancer, salivary gland cancer, peritoneal cancer, gastrointestinal stromal tumor, gastroesophageal junction (GEJ) cancer, mesothelioma, biliary tract cancer, hepatocellular carcinoma, seminoma, soft tissue sarcoma, osteosarcoma, urothelial carcinoma, sweat gland carcinoma, endocrine system cancer, thyroid cancer, medullary thyroid cancer, follicular thyroid cancer, papillary thyroid cancer, parathyroid cancer, kidney cancer, renal parenchymal cancer, renal cell carcinoma, renal pelvic cancer, adrenal cancer, brain cancers such as glioblastoma, astrocytoma, meningioma, medulloblastoma, peripheral neuroectodermal tumors, glioblastoma (including glioblastoma multiforme), neuroblastoma; chronic or acute leukemias, Hodgkin's disease, lymphomas (including lymphocytic lymphoma, Hodgkin lymphoma, non-Hodgkin lymphoma, Burkitt lymphoma, adult T-cell lymphoma, diffuse large B-cell lymphoma (DLBCL), primary CNS lymphoma), acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CLL) and lymphocytic carcinoma, acute myeloid leukemia (AML), myeloid leukemia (chronic myeloid leukemia (CML)), central nervous system (CNS) tumors, spinal tumors, brainstem glioma, or pituitary adenoma.

35. The antibody-drug conjugate or pharmaceutical composition, use, or method according to claim 34, wherein the tumor is selected from lung cancer, lung adenocarcinoma, colon cancer, rectal cancer, pancreatic cancer, endometrial cancer, cholangiocarcinoma, leukemia, and ovarian cancer.

36. A compound fragment having any of the general formulas (ir-3'-1)~(H'-3'-12) and (II'-4'-1) as defined in claim 19, preferably a structural fragment as shown in Table 7 of the specification.

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