Targeting alpha v beta 3 polypeptide nuclide probe as well as preparation method and application thereof

Abstract

The invention relates to the technical field of nuclide probes, and discloses an alpha v beta 3 targeted polypeptide nuclide probe and a preparation method and application thereof, and the alpha v beta 3 targeted polypeptide nuclide probe comprises a radionuclide labeled compound as shown in a formula I. The targeted alpha v beta 3 polypeptide nuclide probe provided by the invention can be used as a diagnosis and treatment reagent to be applied to tumors with high expression of alpha v beta 3 protein in human or animal bodies, and is especially suitable for tumor imaging and radionuclide treatment; animal experiments show that the nuclide probe has a high tumor / muscle uptake ratio and shows good application potential. Formula I.

Description

Technical Field

[0001] This invention relates to the field of radionuclide probe technology, and more specifically, to a radionuclide probe targeting αvβ3 polypeptides, its preparation method, and its application. Background Technology

[0002] Integrins are heterodimeric transmembrane glycoproteins composed of different α and β subunits, playing crucial roles in cell-cell and cell-matrix interactions. Among them, integrin αvβ3 and its role in angiogenesis and tumor metastasis are particularly noteworthy, acting by promoting the migration of endothelial cells and tumor cells. The increasing prevalence of targeted therapy has created an urgent need for imaging monitoring of tumor response to targeted therapy—because only a subset of patients respond positively to these highly specific drugs. However, since anti-angiogenic drugs work by inhibiting tumor progression rather than reducing tumor volume, methods for assessing tumor response based on tumor volume reduction are not applicable, and the assessment process can be very time-consuming. Therefore, there is an urgent need for imaging biomarkers that can predict early tumor responses to non-cytotoxic drugs to predict subsequent clinical efficacy.

[0003] Such biomarkers not only aid in clinical trials of new drugs but can also be used to assist in selecting the optimal treatment plan for individual patients (“personalized medicine”). Positron emission tomography (PET) utilizes tracers [ 18 F]FDG assesses glucose metabolism, [ 18 F]FLT assessment of proliferation or [ 68 [Ga] DOTATOC qualitative assessment of somatostatin receptor (SST receptor) expression has shown promising application prospects in clinical studies evaluating the efficacy of cytotoxic chemotherapy and peptide receptor radiotherapy. Similarly, targeting specific molecular markers of angiogenesis (such as integrin αvβ3) using PET imaging technology can be used to evaluate the efficacy of anti-angiogenic therapies. Since most published studies have focused on imaging integrin αvβ3, and αvβ3 is currently the only integrin successfully visualized in PET imaging, novel radionuclide probes targeting this target are being developed.

[0004] Several extracellular matrix (ECM) proteins, such as fibronectin, fibroinogen, and fibronectin, can interact with integrins via the arginine-glycine-aspartic acid (RGD) amino acid sequence in a single-letter code. Based on these findings, monomeric, multimeric linear peptides, and cyclic peptides containing the RGD sequence have been developed. This has become one of the most prominent lead compounds in the development of molecular imaging compounds for evaluating αvβ3 expression. To evaluate this method for the first time, researchers synthesized radioiodine-labeled RGD peptides that exhibited considerable affinity and selectivity for the lead compounds. In vivo experiments showed that these peptides underwent receptor-specific tumor uptake but were primarily cleared via the hepatobiliary pathway, resulting in high radioactive concentrations in the liver and intestines, which is detrimental to patient studies. Therefore, there is a need to develop radionuclide probes with advantages such as high active targeting, strong specificity, and good water solubility.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] To address the problems in related technologies, this invention proposes a targeting αvβ3 polypeptide radionuclide probe, its preparation method, and its application, in order to overcome the aforementioned technical problems existing in the existing related technologies.

[0007] This invention utilizes a strategy of enhancing tumor uptake with triglutamate and enhancing tumor penetration with the CRGDKGPDC amino acid sequence to obtain a novel αvβ3-targeting radioligand, which is then used for PET imaging. From its design, synthesis, and in vitro and in vivo evaluation, this radionuclide probe can specifically target αvβ3-overexpressing tumors, enabling non-invasive tumor diagnosis and monitoring.

[0008] Therefore, the specific technical solution adopted by the present invention is as follows: According to a first aspect of the present invention, a targeting αvβ3 polypeptide nuclide probe is provided, the targeting αvβ3 polypeptide nuclide probe comprising a radiolabeled compound of formula I:

[0009] Formula I; Wherein, the Y group can be either group I or group II. Linkage sites of representative groups:

[0010] Group I and Group II.

[0011] Furthermore, the radionuclides include 55 Co、 68 Ga、 64 Cu、 86 Y、 89Zr、 90 Y、 111 In、 177 Lu、 225 Any one of Ac, preferably 68 Ga.

[0012] Furthermore, the radiolabeled compound of formula I is either NY-αvβ3-R1 or NY-αvβ3-R2; The structural formula of NY-αvβ3-R1 is:

[0013] The structural formula of NY-αvβ3-R2 is: .

[0014] According to a second aspect of the present invention, a method for preparing a αvβ3 peptide-based nuclide probe is provided, the method comprising: S1. Synthesis begins from the rightmost end of the peptide DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-OH. FMOC-Cys-OH is coupled to the resin using condensation reagents DIEA and DCM as solvents. After reacting at room temperature, methanol and DCM solutions are added, followed by the addition of DIEA to block unreacted sites on the resin. The reaction formula is shown below: ; S2, FMOC removal: FMOC is removed using a DMF solution containing 20% ​​piperidine at room temperature. After removal, the resin is washed with DMF to obtain the resin peptide NH2-Cys-resin. The reaction formula is shown below: ; S3, FMOC-Asp-OH condensation: FMOC-Asp-OH and the resin peptide are dehydrated and condensed using DIC+HOBT and DMF as solvents, yielding FMOC-Asp-Cys-resin at room temperature. The reaction formula is shown below: ; S4. Repeat steps S2-S3 to sequentially condense the remaining amino acids to complete the synthesis of the DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide, where the reaction formula is shown below: ; S5. Peptide cleavage: The DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide was cleaved using a cleavage buffer. After cleavage, the cleavage liquid was filtered into ice-cold ether and lyophilized to obtain peptide PFFC. The peptide PFFC was then dissolved and lyophilized. The reaction formula is shown below: ; S6. Polycyclization of peptide disulfide bonds: The lyophilized peptide PFFC was dissolved in acetonitrile and water, and then the pH was adjusted to weakly alkaline with ammonium bicarbonate and stirred to form disulfide bonds. The formation of disulfide bonds was monitored by mass spectrometry. The reaction formula is shown below: ; S7. Radioactive Labeling: A sodium acetate solution, a compound solution according to Formula I, and a radionuclide solution are mixed and reacted to obtain the αvβ3-targeting polypeptide-like nuclide probe, wherein the reaction formula is shown below: .

[0015] Furthermore, in step S1, the reaction time at room temperature is 1.5 h, and the reaction time after adding DIEA is 20 min.

[0016] Furthermore, in step S2, the reaction time at room temperature is 20 minutes, the resin is washed 4 times, and each washing time is 1 minute.

[0017] Furthermore, in step S3, the reaction time at room temperature is 1 hour.

[0018] Furthermore, in step S5, the lysis solution is composed of 95% TFA, 1% H2O, 2% EDT and 2% TIS, and the lysis time is 2 hours.

[0019] Furthermore, in step S7: And / or, the volume ratio of sodium acetate solution to radioactive nuclide solution is 1:1; And / or, the concentration of the sodium acetate solution is 1~3 M, and the pH is 4; And / or, the concentration of the compound solution represented by Formula I is 5 × 10⁻⁶. -6 M; And / or, the radioactivity of the radionuclide solution is 1~10 mCi; And / or, the radiolabeling temperature is 85~95℃, and the radiolabeling time is 5~20 min.

[0020] According to a third aspect of the present invention, the use of the above-described αvβ3-targeting polypeptide nuclide probe or its racemic mixture, stereoisomer, or pharmaceutically acceptable salt in the preparation of a reagent for tumor imaging is provided. Among them, tumors include any one of triple-negative breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer, and glioblastoma.

[0021] According to a fourth aspect of the present invention, the use of the above-described αvβ3-targeting polypeptide nuclide probe or its racemic, stereoisomer, or pharmaceutically acceptable salt thereof in the preparation of a reagent for identifying αvβ3-overexpressing tumors is provided.

[0022] The beneficial effects of this invention are as follows: 1) This invention utilizes a solid-phase synthesis method to synthesize a series of radionuclide probes. The chelating agent and Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys are linked by a long chain of triglutamate. The final product not only has good water solubility and can be rapidly cleared in normal tissues, but also triglutamate can enhance the uptake of drugs by tumors, thereby quickly achieving the tumor background signal ratio that meets clinical needs.

[0023] 2) The specific targeting αvβ3 polypeptide nuclide probe synthesized in this invention binds to the integrin receptor specifically expressed by tumor vascular endothelial cells and is hydrolyzed into CRGDK / R. The exposed C-terminal CendR motif (R / KXXR / K) can specifically bind to neurociliary protein-1 (NRP-1). The bound NRP-1 can stimulate the permeability of tumor tissue and allow the chelating agent to penetrate into deep tumor tissue. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 High-performance liquid chromatography of NY-αvβ3-DOTA provided in Example 1; Figure 2 The mass spectrum of NY-αvβ3-DOTA provided in Example 1; Figure 3 The αvβ3 polypeptide-like nuclide probe provided in Example 1 68 A diagram illustrating the specific targeting effect of Ga-NY-αvβ3-DOTA on triple-negative breast cancer. Figure 4The αvβ3 polypeptide-like nuclide probe provided in Example 1 68 Tumor-to-muscle SUV ratio at different time points in triple-negative breast cancer (Ga-NY-αvβ3-DOTA); Figure 5 The αvβ3 polypeptide-like nuclide probe provided in Example 1 68 Organ distribution histogram of Ga-NY-αvβ3-DOTA. Detailed Implementation

[0026] Unless otherwise defined herein, the scientific and technical terms used in conjunction with this invention shall have the meanings commonly understood by one of ordinary skill in the art. The meaning and scope of terms shall be clear; however, in any case of potential ambiguity, the definitions provided herein shall prevail over any dictionary or foreign definitions. In this application, unless otherwise stated, the use of "or" means "and / or". Furthermore, the use of the term "comprising" and other forms is non-limiting.

[0027] It should be noted that specific details are set forth in the following description to provide a full understanding of the invention. However, the invention can be practiced in many ways other than those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] According to a first aspect of the present invention, a targeting αvβ3 polypeptide nuclide probe is provided, the targeting αvβ3 polypeptide nuclide probe comprising a radiolabeled compound of formula I:

[0030] Formula I; Wherein, the Y group can be either group I or group II. Linkage sites of representative groups:

[0031] Group I and Group II.

[0032] In this invention, a novel radionuclide probe with αvβ3 targeting capability was designed and synthesized. Using Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys as the recognition group, and linking triglutamate with a chelating agent Y (NOTA, DOTA), a novel radionuclide probe with αvβ3 targeting capability was constructed. This probe can specifically target and identify αvβ3-overexpressing tumors. The radionuclide probe obtained in this invention can specifically recognize αvβ3-overexpressing tumors and can be rapidly cleared in normal tissues, thereby quickly achieving a tumor background signal ratio (TBR>1.5) that meets clinical requirements for preoperative tumor PET imaging.

[0033] The specific targeting αvβ3 polypeptide nuclide probe synthesized in this invention binds to the integrin receptor specifically expressed by tumor vascular endothelial cells, and is hydrolyzed into CRGDK / R. The exposed C-terminal CendR motif (R / KXXR / K) can specifically bind to neurociliary protein-1 (NRP-1). The bound NRP-1 can stimulate the permeability of tumor tissue, allowing the chelating agent to penetrate into deep tumor tissue.

[0034] As an optional implementation, the radiolabeled compound of Formula I is either NY-αvβ3-R1 or NY-αvβ3-R2. The structural formula of NY-αvβ3-R1 is:

[0035] The structural formula of NY-αvβ3-R2 is: .

[0036] As an optional implementation, the radionuclide includes 55 Co、 68 Ga、 64 Cu、 86 Y、 89 Zr、 90 Y、 111 In、 177 Lu、 225 Any one of Ac.

[0037] In a preferred embodiment, the radionuclide is 68 Ga.

[0038] According to a second aspect of the present invention, a method for preparing a αvβ3 peptide-based nuclide probe is provided, the method comprising: S1. Synthesis begins at the rightmost end of the peptide DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-OH. 0.195 mmol (1.3 eq) FMOC-Cys-OH is coupled to the resin using 0.5 mmol DIEA (N,N-diisopropylethylamine) and 3 ml DCM as solvents. After reacting at room temperature for 1.5 h, 0.5 mmol methanol and 10 ml DCM solution are added, followed by the addition of DIEA and a 20 min reaction to block unreacted sites on the resin. The reaction formula is shown below: ; S2, FMOC removal: FMOC was removed using a DMF solution containing 20% ​​piperidine. The reaction was carried out at room temperature for 20 min. After removal, the resin was washed four times with DMF for 1 min each time to obtain the resin peptide NH2-Cys-resin. The reaction formula is shown below: ; S3, FMOC-Asp-OH condensation: 0.5 mmol FMOC-Asp-OH (3 eq) and the resin peptide were dehydrated and condensed using 0.5 mmol DIC (N,N'-diisopropylcarbodiimide) + 0.5 mmol HOBT (1-hydroxybenzotriazole) and 3 ml DMF as solvents. The reaction was carried out at room temperature for 1 h to obtain FMOC-Asp-Cys-resin. The reaction formula is shown below: ; S4. Repeat steps S2-S3 to sequentially condense the remaining amino acids (C-terminus to N-terminus) to complete the synthesis of the DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide, as shown in the following reaction formula: ; S5. Peptide lysis: The DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide was lysed using lysis buffer. After lysis, the lysate was filtered into ice-cold diethyl ether (anhydrous diethyl ether was pre-cooled at -20℃ for ≥2 hours, and 10 mL of diethyl ether was used to precipitate the peptide with 1 mL of cleavage reagent) and lyophilized to obtain peptide PFFC. The peptide PFFC was then dissolved and lyophilized. The reaction formula is shown below: ; The pyrolysis solution consisted of 95% TFA, 1% H2O, 2% EDT and 2% TIS, and the pyrolysis time was 2 hours. S6. Polycyclization of Disulfide Bonds in Peptides: The lyophilized peptide PFFC was dissolved in 10% acetonitrile and water at a concentration of 2 mg / ml. The pH was adjusted to approximately 8 with ammonium bicarbonate and stirred to form disulfide bonds. The completeness of disulfide bond formation was monitored by mass spectrometry. The reaction formula is shown below: ; S7. Radioactive Labeling: A sodium acetate solution, a compound solution according to Formula I, and a radionuclide solution are mixed and reacted to obtain the αvβ3-targeting polypeptide-like nuclide probe, wherein the reaction formula is shown below: .

[0039] As an optional implementation, the radioactive labeling includes the following steps: mixing a sodium acetate solution, a compound solution of Formula I, and a radionuclide [ 68 The Ga]GaCl3 solution was mixed and reacted to obtain the target αvβ3 polypeptide nuclide probe.

[0040] As an optional implementation, the volume ratio of the sodium acetate solution to the radionuclide solution is 1:1.

[0041] As an optional implementation, the concentration of the sodium acetate solution is 1~3 M, for example, it can be 1 M, 1.2 M, 1.5 M, 1.8 M, 2 M, 2.2 M, 2.5 M, 2.8 M, 3 M, etc., preferably 2 M, and the pH is 4.

[0042] As an optional implementation, the concentration of the compound solution represented by Formula I is 5 × 10⁻⁶. -6 M.

[0043] As an optional implementation, the radioactivity of the radionuclide solution is 1~10 mCi, for example, it can be 1 mCi, 2 mCi, 3 mCi, 4 mCi, 5 mCi, 6 mCi, 7 mCi, 8 mCi, 9 mCi, 10 mCi, etc., preferably 5 mCi.

[0044] As an optional implementation, the temperature of the radioactive labeling is 85~95℃, for example, it can be 85℃, 86℃, 87℃, 88℃, 89℃, 90℃, 91℃, 92℃, 93℃, 94℃, 95℃, etc., and the radioactive labeling time is 5~20min, for example, it can be 5 min, 6 min, 8 min, 10 min, 12 min, 14 min, 15 min, 16 min, 18 min, 20 min, etc.

[0045] In a preferred embodiment, the radioactive labeling specifically includes the following steps: Using a 5 mL EP tube as the reaction vessel, 1 mL of 2M sodium acetate solution (pH=4), 10 μg of the compound solution shown in Formula I, and 1 mL of […] were added sequentially. 68 A GaCl3 radionuclide solution (5 mCi) was used to heat the mixed leaves to 90°C and react for 10 min to obtain the target αvβ3 polypeptide-like nuclide probe. 68 Ga-NY-αvβ3-DOTA.

[0046] According to a third aspect of the invention, there is provided the use of a targeting αvβ3 polypeptide nuclide probe or its racemic, stereoisomer, or pharmaceutically acceptable salt as described in the first aspect in the preparation of a reagent for tumor imaging.

[0047] This invention relates to a radionuclide probe targeting αvβ3 polypeptides and its applications, specifically a compound of Formula I, or its precursor compound, isotopic compound, salt, or hydrate. This compound, when labeled with a radionuclide, yields a class of radionuclide probes targeting αvβ3 polypeptides. These probes can be used as diagnostic and therapeutic agents in lesions with high αvβ3 protein expression in humans or animals, particularly as tumor imaging agents and radionuclide therapeutic drugs. In animal experiments, the radiocomplex of this invention exhibits a high tumor / muscle ratio, demonstrating promising application prospects.

[0048] As an optional implementation, the tumor includes any one of triple-negative breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer, and glioblastoma.

[0049] As an optional implementation, the present invention provides a triple-negative breast cancer tumor imaging model and a method for establishing the model, which specifically includes the following steps: inoculating a triple-negative breast cancer cell line with high expression of αvβ3 into the axilla of a mouse, and injecting the αvβ3 nuclide probe described in the present invention via tail vein injection.

[0050] It is important to note that after the triple-negative breast cancer imaging model is established, small animal PET imaging equipment is used to visualize the small molecules in triple-negative breast cancer.

[0051] According to a fourth aspect of the invention, there is provided the use of a targeting αvβ3 polypeptide nuclide probe or its racemic, stereoisomer, or pharmaceutically acceptable salt as described in the first aspect in the preparation of a reagent for identifying αvβ3-overexpressing tumors.

[0052] To facilitate understanding of the above technical solutions of the present invention, the present invention will be further described below through embodiments. Unless otherwise specified, the materials in the embodiments are prepared according to existing methods or purchased directly from the market.

[0053] As mentioned in this invention, the term "pharmaceutically acceptable salt" means that the salt is not only physiologically acceptable to the subject, but also refers to a synthetic substance that has pharmaceutical value, such as a salt formed as an intermediate during chiral resolution, although such intermediate salt cannot be directly given to the subject, but can play a role in obtaining the end product of this invention.

[0054] As mentioned in this invention, a pharmaceutically acceptable salt of the compound represented by Formula I is a salt formed with an alkali or alkali metal. Acids that form pharmaceutically acceptable salts with the compound represented by Formula I include inorganic acids and organic acids. More specifically, alkali metals that form pharmaceutically acceptable salts with the compound represented by Formula I include, but are not limited to, lithium, sodium, potassium, magnesium, calcium, aluminum, zinc, etc.; bases that form pharmaceutically acceptable salts with the compound represented by Formula I include, but are not limited to, choline, diethanolamine, morpholine, etc.

[0055] Example 1 This embodiment provides a radionuclide probe targeting αvβ3 polypeptides, wherein the radionuclide probe targeting αvβ3 polypeptides is a radionuclide. 68 Ga-marked [ 68 The structural formula of Ga]Ga-NY-αvβ3-DOTA is shown below: .

[0056] The radionuclide 68 Ga-labeled NY-αvβ3-DOTA (denoted as Ga) 68 The synthesis route for Ga-NY-αvβ3-DOTA is shown below: 1. Synthesis began from the rightmost end of the peptide DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-OH. 0.195 mmol (1.3 eq) FMOC-Cys-OH was coupled to the resin using 0.5 mmol DIEA and 3 ml DCM as solvents. After reacting at room temperature for 1.5 h, 0.5 mmol methanol and 10 ml DCM solution were added, followed by the addition of DIEA and a 20 min reaction to block unreacted sites on the resin. The reaction formula is shown below: ; 2. FMOC Removal: FMOC was removed using a DMF solution containing 20% ​​piperidine. The reaction was carried out at room temperature for 20 min. After removal, the resin was washed four times with DMF for 1 min each time to obtain the resin peptide NH2-Cys-resin. The reaction formula is shown below: ; 3. FMOC-Asp-OH Condensation: 0.5 mmol FMOC-Asp-OH (3 eq) and the resin peptide were dehydrated and condensed using 0.5 mmol DIC + 0.5 mmol HOBT and 3 ml DMF as solvents. The reaction was carried out at room temperature for 1 h to obtain FMOC-Asp-Cys-resin. The reaction formula is shown below: ; 4. Repeat steps 2-3 to sequentially condense the remaining amino acids (C-terminus to N-terminus) to complete the synthesis of the DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide, as shown in the following reaction formula: ; 5. Peptide lysis: The DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide was lysed using a lysis buffer (the lysis buffer consisted of 95% TFA, 1% H2O, 2% EDT, and 2% TIS; the lysis time was 2 hours). After lysis, the lysate was filtered into ice-cold diethyl ether (anhydrous diethyl ether was pre-cooled at -20°C for ≥2 hours; 1 ml of cleavage reagent was used to precipitate the peptide in 10 mL of diethyl ether) and then lyophilized to obtain peptide PFFC. The peptide PFFC was then dissolved and lyophilized. The reaction formula is shown below: ; 6. Polycyclization of peptide disulfide bonds: The lyophilized peptide PFFC was dissolved in 10% acetonitrile and water at a concentration of 2 mg / ml. The pH was adjusted to approximately 8 with ammonium bicarbonate and stirred to form disulfide bonds. The formation of the DOTA-(γ-E)3-CRGDKGPDC-OHDisulfide Bridge (C1-C9) was monitored by mass spectrometry. The reaction formula is shown below: ; 7. Radioactive labeling: A sodium acetate solution, a compound solution according to Formula I, and a radionuclide solution are mixed and reacted to obtain the target αvβ3 polypeptide-like nuclide probe, wherein the reaction formula is shown below: .

[0057] The structure was characterized by high performance liquid chromatography and mass spectrometry, and the structural determination results are as follows: like Figure 1 As shown, the purity of NY-αvβ3-DOTA is 95.668%.

[0058] like Figure 2As shown, LCMS (ESI): m / z: Chemical Formula: C 66 H 104 N 20 O 30 S2, [M+2H]2H + Found 861.7, [M+3H]3H + Found 574.85, [M+4H]4H + Found 431.40.

[0059] like Figure 3 As shown, at different time points after injection, triple-negative breast cancer-bearing mice exhibited high radioactive signals in the tumor area, indicating that... 68 Ga-NY-αvβ3-DOTA exhibits good specificity in identifying tumors overexpressing αvβ3.

[0060] like Figure 4 As shown, the target-to-tumor ratio increases over time, proving... 68 Ga-NY-αvβ3-DOTA has a longer retention time in tumors and a cleaner background signal, showing promising clinical application prospects.

[0061] like Figure 5 As shown, 68 Ga-NY-αvβ3-DOTA's strong hydrophilic negative charge effectively prevents it from binding to proteins, promoting rapid clearance of the tracer via the kidneys, thereby achieving low liver background and high targeting signal-to-noise ratio.

[0062] Application Example 1 This application example demonstrates the use of an αvβ3-targeting polypeptide-based nuclide probe in the specific identification of triple-negative breast cancer. Triple-negative breast cancer cells with high αvβ3 expression were seeded under the armpit of Balb / c nude cells, and 3.33 MBq of the αvβ3-targeting polypeptide-based nuclide probe provided in Example 1 was injected via the tail vein. 68 The efficacy of Ga-NY-αvβ3-DOTA molecules in diagnosing breast cancer was evaluated using a small animal PET / MR in vivo imaging system.

[0063] Figure 3 The αvβ3 polypeptide-like nuclide probe provided in Example 1 68 A diagram illustrating the specific targeting effect of Ga-NY-αvβ3-DOTA on triple-negative breast cancer. (See diagram for reference.) Figure 3 As shown, at different time points after injection, triple-negative breast cancer-bearing mice exhibited high radioactive signals in the tumor area, indicating that... 68 Ga-NY-αvβ3-DOTA exhibits good specificity in identifying tumors overexpressing αvβ3.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A probe targeting an αvβ3 polypeptide nuclide, characterized in that, The targeting αvβ3 polypeptide nuclide probe comprises a radiolabeled compound of formula I: Formula I; Wherein, the Y group is either group I or group II: Group I and Group II; The radionuclides include 55 Co、 68 Ga、 64 Cu、 86 Y、 89 Zr、 90 Y、 111 In、 177 Lu、 225 Any one of Ac.

2. The αvβ3 polypeptide-based nuclide probe according to claim 1, characterized in that, The radionuclide-labeled compound represented by Formula I is either NY-αvβ3-R1 or NY-αvβ3-R2. The structural formula of NY-αvβ3-R1 is: The structural formula of NY-αvβ3-R2 is: 。 3. A method for preparing a αvβ3-targeting polypeptide-based nuclide probe, used to achieve the preparation of the αvβ3-targeting polypeptide-based nuclide probe according to any one of claims 1-2, characterized in that, The preparation method includes: S1. Synthesis begins from the rightmost end of the peptide DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-OH. FMOC-Cys-OH is coupled to the resin using condensation reagents DIEA and DCM as solvents. After reacting at room temperature, methanol and DCM solutions are added, followed by the addition of DIEA to block unreacted sites on the resin. The reaction formula is shown below: ； S2, FMOC removal: FMOC is removed using a DMF solution containing 20% ​​piperidine at room temperature. After removal, the resin is washed with DMF to obtain the resin peptide NH2-Cys-resin. The reaction formula is shown below: ； S3, FMOC-Asp-OH condensation: FMOC-Asp-OH and the resin peptide are dehydrated and condensed using DIC+HOBT and DMF as solvents, yielding FMOC-Asp-Cys-resin at room temperature. The reaction formula is shown below: ； S4. Repeat steps S2-S3 to sequentially condense the remaining amino acids to complete the synthesis of the DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide, where the reaction formula is shown below: ； S5. Peptide cleavage: The DOTA-Glu-Glu-Glu-Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys-resin peptide was cleaved using a cleavage buffer. After cleavage, the cleavage liquid was filtered into ice-cold ether and lyophilized to obtain peptide PFFC. The peptide PFFC was then dissolved and lyophilized. The reaction formula is shown below: ； S6. Polycyclization of peptide disulfide bonds: The lyophilized peptide PFFC was dissolved in acetonitrile and water, and then the pH was adjusted to weakly alkaline with ammonium bicarbonate and stirred to form disulfide bonds. The formation of disulfide bonds was monitored by mass spectrometry. The reaction formula is shown below: ； S7. Radioactive Labeling: A sodium acetate solution, a compound solution according to Formula I, and a radionuclide solution are mixed and reacted to obtain the αvβ3-targeting polypeptide-like nuclide probe, wherein the reaction formula is shown below: 。 4. The method for preparing a αvβ3-targeting polypeptide-based nuclide probe according to claim 3, characterized in that, In step S1, the reaction time at room temperature is 1.5 h, and the reaction time after adding DIEA is 20 min.

5. The method for preparing a αvβ3-targeting polypeptide-based nuclide probe according to claim 3, characterized in that, In step S2, the reaction time at room temperature is 20 min, the resin is washed 4 times, and each washing time is 1 min.

6. The method for preparing a αvβ3-targeting polypeptide-based nuclide probe according to claim 3, characterized in that, In step S3, the reaction time at room temperature is 1 hour.

7. The method for preparing a αvβ3-targeting polypeptide-based nuclide probe according to claim 3, characterized in that, In step S5, the lysis buffer is composed of 95% TFA, 1% H2O, 2% EDT and 2% TIS, and the lysis time is 2 hours.

8. The method for preparing a αvβ3-targeting polypeptide-based nuclide probe according to claim 3, characterized in that, In step S7: And / or, the volume ratio of sodium acetate solution to radioactive nuclide solution is 1:1; And / or, the concentration of the sodium acetate solution is 1~3 M, and the pH is 4; And / or, the concentration of the compound solution represented by Formula I is 5 × 10⁻⁶. -6 M; And / or, the radioactivity of the radionuclide solution is 1~10 mCi; And / or, the radiolabeling temperature is 85~95℃, and the radiolabeling time is 5~20 min.

9. The use of a targeting αvβ3 polypeptide radionuclide probe according to any one of claims 1 to 2, or its racemic mixture, stereoisomer, or pharmaceutically acceptable salt thereof, in the preparation of a reagent for tumor imaging; in, The tumors include any one of triple-negative breast cancer, ovarian cancer, non-small cell lung cancer, pancreatic cancer, and glioblastoma.

10. The use of a targeting αvβ3 polypeptide radionuclide probe according to any one of claims 1 to 2, or its racemic mixture, stereoisomer, or pharmaceutically acceptable salt thereof, in the preparation of a reagent for identifying αvβ3 overexpressing tumors.

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