Methods and products for modelling immuno-oncology therapy ex vivo

Abstract

The field of the invention belongs to in vitro assays for producing an in vitro organ culture system, and the use of such an in vitro organ culture system for screening assays in the context of drug screening, patient selection, and personalized medicine. More specifically, the invention relates to an in vitro method of establishing tumor organoids from a cancer tissue sample obtained from a subject, to an in vitro method of providing autologous tumor organoid-activated immune cells, to a method of preparing an in vitro organ culture system for mimicking tumor interaction with an immune system of a subject, as well as to the in vitro organ culture system produced thereby, to a method for determining the responsiveness of a tumor to a treatment with at least one immune- oncologic drug applying said in vitro organ culture system, and a kit-in-parts for preparing an in vitro organ culture system mimicking tumor interaction with an immune system of a subject, as disclosed herein.

Description

[0001]METHODS AND PRODUCTS FOR MODELLING IMMUNO-ONCOLOGY THERAPYEXVIVOFIELD OF THE INVENTION The field of the invention belongs to in vitro assays for producing an in vitro organ culture system, and the use of such an in vitro organ culture system for screening assays in the context of drug screening, patient selection, and personal- ized medicine. More specifically, the invention relates to an in vitro method of es- tablishing tumor organoids from a cancer tissue sample obtained from a subject, to an in vitro method of providing autologous tumor organoid-activated immune cells, to a method of preparing an in vitro organ culture system for mimicking tumor in- teraction with an immune system of a subject, as well as to the in vitro organ culture system produced thereby, to a method for determining the responsiveness of a tu- mor to a treatment with at least one immune-oncologic drug applying said in vitro organ culture system, and a kit-in-parts for preparing an in vitro organ culture sys- tem mimicking tumor interaction with an immune system of a subject, as disclosed herein. BACKGROUND OF THE INVENTION Immunotherapies including immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment and changed disease management in several can- cer types. The anti-programmed death cell protein-1 (PD-1) or anti-cytotoxic T- lymphocyte associated antigen 4 (CTLA-4) are ICIs that can promote anti-tumor activity resulting in durable clinical benefits in various cancers. Albeit the long- term efficacy provided by immunotherapy, the overall response rates (ORR) to anti-PD-1 therapy in, e.g., first-line melanoma treatment range from 40-50 % and in second-line non-small-cell lung cancer (NSCLC) from 18-40 %. Currently, the success of immuno-oncology (IO) drugs is hampered by the lack of reliable biomarkers making it difficult to predict which patients will re- spond to the treatment. Although tumor PD-L1 expression guides the use of anti- PD-1 therapies in NSCLC and other cancers, the use of PDL-1 expression as a bi- omarker has been controversial due to its dynamic nature and poor predictive ca- pabilities. Beyond PD-1 / PD-L1 and CTLA-4, several other immune checkpoints such as lymphocyte activation gene-3 (LAG-3), T cell immunoglobulin and mucin- domain containing-3 (TIM-3), as well as cytokines contribute to immune-evasion and resistance to immunotherapy. There is a growing interest in combining ICIs as a way to overcome re- sistance to IO treatments. Combination strategies of ICIs have shown better out- comes in some cases but also resulted in some cases in high toxicity. Several clinical studies for IO combinations are currently underway, but they fail to keep up with the rapid development of new immunotherapeutic agents. As a result, there is an increasing need for sophisticated pre-clinical platforms that closely mimic the complexity of a patient’s tumor microenvironment (TME). Such a platform would enable clinicians to make more informed decisions regarding the use of costly IO-drugs, while also providing more accurate represen- tation of how the drugs might work in vivo. Current pre-clinical models for evaluating the efficacy of IO treatments have significant limitations. While patient tumor-derived 3D organoids lack the im- mune contexture, humanized mice are insufficient in terms of reproducibility cost. Recently, microfluidic systems have been developed to evaluate re- sponses to ICIs using tumor fragments (Jenkins et al., 2018). Although these plat- forms replicate some features of the patient’s TME, their applications are limited by the small size of tumor resections and the absence of systemic immune effects. Previous studies have established tumor-on-chip technology, but they are not personalized or systemic and cannot be utilized to screen for therapeutic options in different patients. Nguyen et al., 2018 developed a platform to screen for targeted therapy in breast cancer and study the effects of fibroblasts on tumor growth, treatment efficacy and immune cells. However, the platform consisted of commercial tumor and fibroblasts cell lines and immune cells were derived from unmatching healthy donors. Similarly, Ayuso et al., 2019 and 2021 developed a mi- crofluidic platform to study the systemic effects of NK-92 cell line in a breast cancer cell line in the presence of different antibodies. Although these approaches have successfully integrated the main features of the TME in their platforms, they are not personalized or systemic, and cannot be utilized to screen for therapeutic op- tions in different patients. Other approaches to study responses to IO drugs or for cell-based ther- apy rely on tumor-infiltrated lymphocytes (TIL) as a source of immune cells. This strategy has been successful in melanomas but remained limited in epithelial can- cers (Rosenberg et al., 2015). It has been shown that not all TILs are tumor-specific (Simoni et al., 2018). Moreover, some tumors have a low number of infiltrated T cells, or patient specimens obtained by biopsy are small hence, limited amount of immune cells, such as T cells, can be obtained. Other microfluidics-based approaches, which use inactivated or non- specifically activated peripheral blood mononuclear cells (PBMCs) or commer- cially available non-matching immune cell lines, also lack personalized tumor spe- cific T cells (Aung et al., 2020, Al-Samadi et al., 2019, De Haan et al., 2021). Cattaneo et al.2020 describes a method of activating PBMC with tumor organoid. However, Cattaneo et al. do not provide tumor organoid that comprise cells from different culture conditions. Moreover, Cattaneo also sets forth in the abstract that tumor reactive T-cells were obtained from ~33-50% of non-small cell lung cancer (NSCLC) and microsatellite instable (MSI) colorectal cancer (CRC) pa- tient samples”, which is significantly lower percentage compared to the over 80% success rate found with the method of the present disclosure. Moreover, Cattaneo et al. also did not include other cells, such as fibroblasts, into the organoids. Schuth et al. (2020) describes a three-dimensional organoid-fibroblast co-culture system and discuss the importance of creating heterotypic tumor organ- oid models that more accurately reflect the real-life tumors. Schuth et al. do not describe using 2D-culture to grow additional tumor epithelial cells to overcome the difficulty of obtaining enough cells from tumor samples and they do not combine their system with immune cells, systemic or otherwise, included into the tumor or- ganoid system. US Patent No.10,472,599 describes a 3D cell culture system in a micro- fluidic device using primary tumor cells that have been separated from the tumor samples by an enzymatic digestion and embedded into a matrix inside a microflu- idic chip to allow growth of primary tumor-originated spheroids, which do not in- clude fibroblasts or cells from a 2D culture. The use of autologous, primary tumor- activated systemic immune cells is not described. Maulana et al.2021 discusses immunocompetent cancer-on-chip mod- els to assess immuno-oncology therapy. While Maulana et al. appear to outline a desire to create systems to study drugs in a more realistic tumor microenviron- ment, they do not appear to describe a system that accomplishes this object. Gopal et al. 2021, describes a high throughput micropillar-microwell sandwich 3D cell culture platform. While the system described in Gopal et al., uses a co-culture of tumor spheroids and NK-cells, it does not disclose or suggest co- culture of tumor cells and primary tumor-activated systemic immune cells. Saraiva et al. August 2020 describe establishment of a 3D Co-culture with a breast cancer cell line and patient-derived Immune cells. Saraiva et al. do not describe using a combination of 3D and 2D cultures or adding additional cells into the system. The system of Saraiva et al. also does not include using microfluidic channels or a blood vessel-like structure between the tumor organoid or the added patient derived PBMCs. Still, there remains a need for a more sophisticated organ-on-chip plat- form that mimics the patient’s TME and includes personalized tumor-specific im- mune cells, including tumor-specific T cells, is urgently needed, which can be used for identifying effective IO drug combinations in a patient. BRIEF DESCRIPTION [DISCLOSURE] OF THE INVENTION To address the above challenges in the prior art, inventors have estab- lished an improved method for preparing tumor organoids. Using patient material to establish tumor organoids may be limited due to the small amount of tissue available, and some epithelial tumor cells may prefer growing in either 2D or 3D culture. The two-step tumor organoid establishment protocol combining 2D and 3D culture steps disclosed herein allows the successful generation of tumor and benign tissue organoids from more than 80 % of the specimens, including the iso- lation of cancer-associated fibroblasts from 45 % of the patients. The disclosed method also allows establishing tumor-matched cancer associated fibroblast (CAF) cell lines. In addition, the such prepared tumor organoids can be used to trigger and activate autologous (i.e. the same patients own) tumor-specific immune cells, such as tumor-specific T cells and NK cells. These all-autologous tumor organoids, CAFs and tumor-specific im- mune cells were then used to develop a personalized ex vivo microfluidic platform referred to herein as “Solid-IO”. Solid-IO is a unique platform that leverages pa- tient-matched tumor and immune cells to evaluate responses to IO drugs. The plat- form allows screening for different IO drug combinations while studying the sys- temic effect of the patient’s tumor specific immune cells. The platform can be used to screen for immunotherapy responses and discover immunotherapy biomarkers in tumors. The organ-on-a-chip platform consists of 3D tumor microenvironment, optionally separated by an endothelial barrier or tubule, and autologous tumor- specific immune cells, with or without stimulation with IO-drugs. Using the plat- form, inventors were able to model cancer primary resistance against checkpoint inhibitors ex vivo and identify individual ex vivo responders for combination of checkpoint inhibitors and chemotherapy. The platform allows, for example, screen- ing for and / or identifying IO-drug combination that are able to overcome drug re- sistance in a given patient. Vice versa, the platform can be used to identify patients who will benefit from a given IO-drug combination. Additionally, the platform al- lows identifying potential biomarker for responsiveness or non-responsiveness to a given IO-drug combination. Solid-IO platform is a high-throughput, easy-to-use tool that has the po- tential to significantly accelerate the discovery of new IO drugs and biomarkers. It has the potential to aid in clinical decision-making in IO treatments, leading to im- proved patient outcomes cost-efficiently. The challenges in the prior art are overcome by methods and an in vitro organ culture system which are characterized by what is stated in the independent claims. The preferred embodiments of the invention are disclosed in the dependent claims. More specifically, provided is an in vitro method of establishing tumor organoids from a cancer tissue sample obtained from a subject, the method com- prising the steps of (a) dissociating the cancer tissue sample into cells and fragments; (b) propagating a first portion of the cells and / or fragments obtained in step (a) in a first 3D-culturing step; (c) propagating a second portion of the cells and / or fragments obtained in step (a) in a 2D-culturing step such as to enrich epithelial tumor cells and option- ally fibroblasts; (d) combining the propagated cells and fragments obtained in step (b) with the propagated cells and fragments obtained in step (c), and propagating the combined cells and fragments in a second 3D-culturing step; thereby establishing tumor organoids from the cancer tissue sample, as further de- fined in the claims. Additionally provided is an in vitro method of providing autologous tu- mor organoid-activated immune cells, wherein the method comprises (a) establishing tumor organoids from a cancer tissue sample obtained from a subject according to the method disclosed herein; and (b) co-culturing the tumor organoids with immune cells obtained from said sub- ject; thereby providing autologous tumor organoid-activated immune cells, as further defined in the claims. Moreover, provided is a method of preparing an in vitro organ culture system for mimicking tumor interaction with an immune system of a subject, the method comprising: (i) providing a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which al- lows a cell to move from the first compartment to the second compartment; (ii) incorporating into the first compartment a three-dimensional tumor organ- oid established from a cancer tissue sample obtained from a subject, and a suitable tumor cell growth medium, and (iii) introducing into the second compartment autologous immune cells from said subject, which have been activated by co-culturing with said estab- lished tumor organoids, and a suitable immune cell growth medium; thereby providing the in vitro organ culture system, as further defined in the claims. The above methods result in the provision of an in vitro organ culture system for mimicking tumor interaction with an immune system of a subject, com- prising: (i) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second compartment; (ii) in the first compartment, a three-dimensional tumor organoid established from a cancer tissue sample obtained from the subject, and a suitable tumor cell growth medium, and (iii) in the second compartment, autologous immune cells from the subject, which have been activated by co-culturing with said established tumor or- ganoids, and a suitable immune cell growth medium; as further defined in the claims. Further provided are applications of the in vitro organ culture system, such as a method for determining the responsiveness of a tumor to a treatment with at least one immune-oncologic drug, comprising the steps of (a) preparing an in vitro organ culture system according to the method dis- closed herein or providing an in vitro organ culture system according to the present disclosure; (b) adding one or more, preferably at least two, immune-oncology drugs into the second compartment; and (c) determining the responsiveness of the in vitro organ culture system to the at least two immune-oncology drugs; as further defined in the claims. Finally, further contemplated is a kit for preparing an in vitro organ cul- ture system mimicking tumor interaction with an immune system of a subject, the kit comprising at least two, preferably at least three, more preferably at least four, even more preferably at least five, and most preferably all of the following: (a) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second compartment, in particu- lar wherein the physical boundary is selected from a membrane, a mechani- cal barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary; (b) a tumor cell growth medium comprising at least two, preferably all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT, preferably R-spondin 1; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF- 10; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190; (c) an immune cell culture medium a culture medium, comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2); (ii) an immune checkpoint inhibitor, preferably an immune checkpoint se- lected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 / PD-L1 antibody, in particular an anti-PD-1 / PD-L1 antibody selected from Nivolumab, Pembrolizumab, Cemi- plimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezolizumab, Durvalumab, and Avelumab, more preferably wherein the anti-PD-1 antibody is Nivolumab; (iii) nicotinamide; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. (d) a cell culture dish or cell culture container, which has been pre-coated with anti-CD28 antibody; (e) a container with IFN-ɣ; and / or (f) a container with an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. BRIEF DESCRIPTION OF THE DRAWINGS In the following the invention will be described in greater detail by means of preferred embodiments with reference to the attached [accompanying] drawings, in which Figure 1 provides a schematic overview of activating patient’s immune cells, including T cells, by co-culturing with tumor organoids established from a tumor of said patient. Figure 2: Co-culture does not significantly change the T cell subpopula- tions. Immune profiling by flow cytometry comparing the bulk percentage of CD3+ cells and sub-populations of CD4+ and CD8+ T cells before (Week 0) and after (Week 2) two-week stimulation with patient-matched tumor organoids. Two scat- ter plot dots of the same color represent biological replicates. Different colored scatter plot dots represent individual patients. The solid black line represents the mean. N / A = no clinically relevant mutation was found. Students t-test (unpaired). Figure 3: (A) Circulating T cells are activated by the stimulation with matching tumor organoids. Example flow cytometry plots showing CD8+ / IFNγ+ cells from 3 example patients. (B) Quantification of IFNγ production by reactive CD8+ T cells after two weeks of PBMC co-culture with matching tumor organoids. Bars in the graph represent the percentage of anti-IFNγ APC in CD8+ T cells relative to control. Bars in the graph represent values of one replicate. For ORG-35, ORG- 54, and LUNG-19, an average of two biological replicates is shown in each bar. Figure 4: IFNγ production by reactive CD8+ T cells in two patients at the baseline (Week 0), after one day of stimulation with new organoids (Week 1), and after two weeks of co-culture with organoids (Week 2). Figure 5: Tumor organoids (ORG-55) killing by baseline PBMCs or stim- ulated immune cells in three conditions (control, Nivolumab, Nivolumab and chem- otherapy combination). The bars indicate log2 fold change of luminescence signal of Cleaved Caspase-3 / 7 after 48 h of co-culture. Figure 6: The Solid-IO design in the AIM or Mimetas 3-lane microfluid- ics. Each device contains a middle channel (the tumor site) where tumor organoids are seeded in Matrigel (extracellular matrix) and separated from two side media channels (the circulation), where activated immune cells and selected drugs are added. A bright-field image (from the AIM chip) acquired by Nikon eclipse micro- scope shows immune cells trafficking and infiltrating to the tumor site surrounding the organoids after 24 h of seeding. Figure 7: Expression of the tumor cell surface immune checkpoint PD- L1 from tumor resections or biopsies provided by HUS pathology-lab. Bars in the graph represent the percentage of tumor cells expressing PD-L1. Figure 8: Quantification of live / dead images after 48 h of co-culture in the Solid-IO platform. Scatter plots of the same color represent technical replicates (except for LUNG-19, two technical replicates from each of two biological replicates are shown). Unpaired t-test was performed to assess differences in responses be- tween conditions with and without immune cells. P values are shown in the graph. The mutational status of every patient is displayed to the right of the graph; N / A = not available. The solid black line represents the mean of values in each condition. Figure 9: Live (AO = white box) and dead (PI = grey box) quantification of LUNG-19 after 48 h of co-culture in the Solid-IO platform. Bars represent the mean of two biological replicates and error bars represent their variance. Unpaired t-test was performed, * = P<0.05, ** = P<0.01, *** = P<0.001, ns = not significant. Bars represent the percentage of live / dead cell area. Figure 10: Advanced set-up of the Solid-IO showing tumor-on-a-chip including the tumor microenvironment (TME) middle channel containing tumor organoids and matched tumor-associated fibroblasts separated from the circula- tion side-channels by an endothelial tubule. In the top-side channel, an endothelial tubule is formed. Immune cells and drugs are injected into the endothelial tubule followed by infiltration of the immune cells to the TME channel. A bright-field im- age (from the Mimetas chip) acquired by Nikon eclipse microscope shows the en- dothelial tubule in the top channel and the TME in the channel below. Figure 11: (A) Live (AO = left column) and dead (PI = right column) quantification of tumor organoids after 48 h of co-culture where tumor site sepa- rated from adjacent channel by a endothelial tubule in the advanced Solid-IO. The quantification is done to two conditions control and chemotherapy that been in- jected to the tubule and needed to diffuse to the tumor site. Bars represent the percentage of live / dead area of tumor organoids. (B) Live (AO = left column) and dead (PI = right column) quantification of the HUVECs cells that form the endothe- lial tubule. Quantification is done to assess the HUVECs cells viability after 4 days for tubule formation and two more days when control or chemotherapy were in- jected in the tubule. Bars represent the live / dead area percentage of HUVECs cells in the tubule channel. Figure 12: Alternative design of the Solid-IO showing tumor-on-a-chip including the tumor microenvironment (TME) middle channel containing tumor organoids and matched tumor-associated fibroblasts separated from the circula- tion side-channels by an endothelial tubule. Figure 13: Different patients have multiple shared as well as individual genes upregulated in the CD4+ (helper) and CD8+ (cytotoxic) T cells after the PBMC / tumor co-culture protocol. DETAILED DESCRIPTION OF THE INVENTION ICIs targeting PD-1 / PD-L1 have shown promise in cancer treatment, but only a small percentage of patients benefit from the current ICIs. Therefore, there is a critical need for more efficient and accurate IO drug testing, as well as lack of pre-clinical models that can accurately predict which patients will benefit from IO treatments. Current 2D and 3D cell models lack the immune contexture and tumor microenvironment, and do not accurately capture the patient antitumor immunity and the complex tumor microenvironment. To address this issue, the methods and devices were developed to include patient-matched tumor and im- mune cells, with the possibility of adding personalized TME components such as fibroblasts and endothelial cells. The platform was designed to be easy-to-use and compatible with high-throughput testing. Using patient material to establish tumor organoids may be limited due to the small amount of tissue available, and some epithelial tumor cells may prefer growing in either 2D or 3D culture. Nevertheless, the presently disclosed two-step organoid establishment protocol allows the successful generation of tumor and be- nign tissue organoids from more than 80 % of the specimens, including the isola- tion of cancer-associated fibroblasts from 45 % of the patients. This straightfor- ward method is mainly dependent on epithelial-to-fibroblast ratios, enriching for either cell type with no need for bead- or flow cytometer-based separation which typically leads to loss of cells and poor cell viability. Moreover, the new 3D / 2D-culture system used in growing the tumor organoids from the patient sample, enables a much more reliable cell proliferation and isolation method to obtain both tumor cells and fibroblasts from the patient both in the context of both resection samples and biopsy samples compared to only using a 3D-culture systems used to grow tumor organoids in prior art references. The heterotypic tumor organoids provide an improved tumor model for the screening system incorporating not only tumor cells but also tumor-associated fi- broblasts. In sum, the presently disclosed method overcomes the disadvantage in the prior art that not all samples grow directly from 3D-organoids. The presently disclosed method is faster than prior art methods in generating more cells, such that drug efficacy tests can be carried out quicker, and the method allows to grow out also matching fibroblast populations. Furthermore, the inventors’ preliminary data shows that the presently disclosed method is particularly useful in preserving cancer mutations in comparison to the prior art. In more generic terms, provided is an in vitro method of establishing tumor organoids from a cancer tissue sample obtained from a subject, the method comprising the steps of (a) dissociating the cancer tissue sample into cells and fragments; (b) propagating a first portion of the cells and / or fragments obtained in step (a) in a first 3D-culturing step; (c) propagating a second portion of the cells and / or fragments obtained in step (a) in a 2D-culturing step such as to enrich epithelial tumor cells and optionally fibroblasts; (d) combining the propagated cells and fragments obtained in step (b) with the propagated cells and fragments obtained in step (c), and propagating the combined cells and fragments in a second 3D-cultur- ing step; thereby establishing tumor organoids from the cancer tissue sample. The cancer tissue sample may be a sample obtained from a tissue se- lected from the group comprising, preferably consisting of, lung, bronchus, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, renal pelvis, uterine cor- pus, oral cavity, or ovarian tissue. However, the sample may also be obtained from a tissue other than the above exemplified. The cancer tissue sample obtained from said tissue may originate from the same type of tissue, or may be a cancer tissue originating from another type of tissue. The cancer tissue sample may be a cancer tissue sample from a benign tu- mor, or from a malignant cancer tumor. The term “malignant” in this respect, means that the tumor has cells that grow uncontrollably and may spread locally and / or to distant sites. Hence, malignant cancer tumor also encompasses meastatic cancer tumor. In case of a malignant tumor, the cancer may, for example, be selected from the group consisting of lung, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, renal, epithelial, or ovarian cancer. Alternatively, or in addition, the cancer tissue sample is a cancer tissue sample from an adenocarcinoma, epider- moid carcinoma, and / or colorectal cancer. However, the sample may also be ob- tained from a cancer other than the above exemplified. In certain embodiments, the method may also be carried out in parallel using non-tumor tissue sample or a healthy sample from the subject or a healthy donor, preferably from the subject, with the aim to provide “non-tumor”-organoids, which can be used as a control in the methods disclosed herein below. For best comparison, the non-tumor or healthy tissue is from the same type of tissue than the cancer tissue sample. While the method is exemplified herein below for use with humans, the system may also be used in the context of subjects other than human. This may be relevant in the context of animal cancer models, including animal models in which human cancer cells have been injected into the animal. Accordingly, the subject may be a mammal; preferably a primate, such as a human; or, without being limit- ing, a rodent such as a mouse, a rat, hamster or a guinea pig; or a cat, dog, sheep, horse or cow. Still, since ‘personalized medicine’ is currently mainly developed for humans, the subject is preferably a human. One particularly advantage of the disclosed method is that it allows to better retain the genetic identity of the cancer tissue in the tumor organoids. This is of particular relevance when testing for personalized immune-oncology drug combinations intended to overcome resistance towards a drug monotherapy. Therefore, the presently disclosed method is particularly advantageous in cases wherein the cancer tissue sample is a cancer tissue sample from a cancer compris- ing at least one mutation in a gene, optionally a gene associated with tumor re- sistance. Some prominent examples for such a mutation is a cancer wherein the at least one mutation is a mutation in a gene selected from the group of genes comprising KRAS, EGFR, KEAP1, ALK, STK11, MET, TP53, ROS1, RB1, NOTCH1, NOTCH2, BRAF, NTRFK1 / 2 / 3, RET, ERBB2, HRAS, NRAS, ASCL1, NF1, PI3CA, FGFR1 / 2, MAP2K1, in particular from the group of genes consisting of KRAS, EGFR, KEAP1, ALK, and STK11. As demonstrated in the Examples, the at least one mutation may, for ex- ample, be a mutation in KRAS. In particular in embodiments wherein the subject is a human, the at least one mutation in KRAS may, for example, be a mutation at po- sition Gly12 and / or Gln61, more specifically at least one mutation in KRAS selected from GL12Ala, Gly12ASP, Gly12Val, Gly12Cys, and Gln61His. In step (a) the cancer tissue sample is dissociated into cells and frag- ments. That is, unlike in organoid-establishment protocols of the prior art, undi- gested tissue fragments are not filtered out, limiting the possibility of losing tumor cell mass or rare tumor cell populations. Having a reliable source of tumor organoid cells is important because the tumor organoids in the described system are used both to activate the immune cells and in the screening system. Step (a) may nevertheless comprise the use of mechanical and / or enzy- matic means for dissociating the cancer tissue sample. For example, the cancer tis- sue sample is minced, for example, into fragments of 1-2 mm3. In addition, or alter- natively, the cancer tissue sample may be treated with enzymes, such as with en- zymes selected from the group consisting of collagenase, thermolysin, trypsin, hy- aluronidase and papain. In particular the use of collagenase has been found useful in this respect. Such enzymes are commercially available, and usually distributed by commercial manufacturers along with protocols for their use. The system with its two-stage (2D / 3D) cell proliferation approach al- lows a much more reliable production of sufficient numbers of tumor cells from patient’s tumor sample compared to prior art methods, whether the sample is a biopsy or a resection, for establishing tumor organoid structures. In contrast to the 2D-culturing step (c), the 3D culturing step (b) is typ- ically carried out in an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. Commerically available examples for such an extracellular matrix gel are Matrigel or Cultrex or Collagen. As exemplified in the experimental section herein below, step (b) typically further comprises propa- gation of the cells and fragmens within the extracellular matrix gel in a culture me- dium comprising at least two or more, preferably all, of the following (i)-(vii): (i) an inducer of the WNT / β catenin signalling pathway, such as R-spondin and / or WNT; for example R-spondin 1. R-spondin, such as R-spondin-1, may for example be present in an effective amount within a typical range of 1-10 000 ng / ml. Preferably, it may be present in a range of 10-5000 ng / ml, more preferably in a range of 100-2000 ng / ml, and even more preferably in a range of 250-1000 ng / ml. As exemplified in the experimental section, it may be present in an amount of about 500 ng / ml. (ii) FGF, for example FGF-7 and / or FGF-10, preferably both FGF-7 and FGF-10. Effective amounts for FGF-7 can be easily determined, and are typically in a range of 0.1-1000 ng / ml, in particular in a range of 1-500 ng / ml, more par- ticularly in a range of 5-200 ng / ml, even more particularly in a range of 10- 100 ng / ml, such as in a range of 15-50 ng / ml. As exemplified in the experi- mental section, FGF-7 may, for example, be present in an amount of about 25 ng / ml. Similarly, typical effective amounts of FGF-10 are in a range of 1- 10000 ng / ml, in particular in a range of 10-5000 ng / ml, more particularly in a range of 25-1000 ng / ml, such as in a range of 50-500 ng / ml. As exem- plified in the experimental section, FGF-10 may, for example, be present in an amount of about 100 ng / ml. (iii) a bone morphogenetic protein (BMP) antagonist. An example of such an an- tagonist is Noggin, and effective amounts of Noggin are typically in a range of 10-1000 ng / ml, in particular in a range of 25-500 ng / ml, more particu- larly in a range of 50-250 ng / ml. As exemplified in the experimental section, an effective amount may be, for example, at about 100 ng / ml. (iv) an ALK5 inhibitor. One example of anALK5 inhibitor is A83-01, which is typ- ically effective in a range of 1-10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, for example in a range of 100-1000 nM. As exemplified in the experimental section, an effective amount may be, for example, at about 500 nM. (v) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y- 27632. Typically, Y-27632 is effectively applied in a range of 0.01-50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM. As exemplified in the experimental section, an effective amount may be, for example, at about 5 µM. (vi) a p38 MAPK inhibitor. One example of a suitable p38 MAPK inhibitor is SB202190, which may be effectively applied in a range range of 1- 10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, such as in a range of 100-1000 nM. As exemplified in the experimental section, an effective amount may be, for example, at about 500 nM. (vii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM. As exemplified in the experimental section, a suitable amount may be, for example, at about 5 mM. Optionally, the medium may additionally contain B27 supplement and N-acetylcysteine, such as about 1.25 mM N-acetylcysteine. Similarly, step (c) of the above method typically comprises propagation in a culture medium comprising at least two or more, preferably all, of the following (i)-(iii): (i) FGF, such as FGF-basic. Typically, effective amounts of FGF-basic are in a range of 0.1 – 10000 ng / ml, in particular in a range of 0.5-5000 ng / ml, more particularly in a range of 1-1000 ng / ml, even more particularly in a range of 5-500 ng / ml, such as in a range of 10-50 ng / ml. As exemplified in the experimental section, a suitable amount may be, for example, at about 20 ng / ml. (ii) EGF, wherein suitable amounts of EGF are typically in a range 0.1- 10000 ng / ml, in particular in a range of 0.5-5000 ng / ml, more particularly in a range of 1-2000 ng / ml, even more particularly in a range of 2-1000 ng / ml, still even more particularly in a range of 5-500 ng / ml, such as in a range of 10-100 mg / ml. As exemplified in the experimental section, a suitable amount may be, for example, at about 50 ng / ml. (iii) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y- 27632. Effective amounts of Y-27632 are typically in a range of 0.01-50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM, such as at about 5 µM. Typically, step (c) is carried out for at least 2-6 days, such as for at least 4-6 days. In addition or alternatively, step (d) is carried out no later than at passage 3, in particular no later than at passage 2, more particularly no later than at passage 1, such as at passage 0 of the epithelial tumor cells. Step (c) may further comprise steps of collecting and propagating can- cer-associated fibroblasts, preferably in the same culture medium than the culture medium used in step (c). This allows culture and inclusion of autologous fibroblasts into the tumor organoid structure, thereby providing heterotypic tumor organoids that more accurately reflect the real-life tumors. Similar to step (b), step (d) is usually carried out in an extracellular ma- trix gel, comprising extracellular matrix proteins, such as laminin and collagen. For example, step (d) may be carried out in Matrigel or Cultrex. As exemplified in the experimental section herein below, step (d) typically further comprises propaga- tion in a culture medium, which is the same or similar to the culture medium used in step (b). Accordingly, in embodiments, it comprises at least two or more, prefer- ably all, of the following (i)-(vii): (i) an inducer of the WNT / β catenin signalling pathway, such as R-spondin and / or WNT; for example R-spondin 1. R-spondin, such as R-spondin-1, may for example be present in an effective amount within a typical range of 1-10 000 ng / ml. Preferably, it may be present in a range of 10-5000 ng / ml, more preferably in a range of 100-2000 ng / ml, and even more preferably in a range of 250-1000 ng / ml. As exemplified in the experimental section, it may be present in an amount of about 500 ng / ml. (ii) FGF, for example FGF-7 and / or FGF-10, preferably both FGF-7 and FGF-10. Effective amounts for FGF-7 can be easily determined, and are typically in a range of 0.1-1000 ng / ml, in particular in a range of 1-500 ng / ml, more par- ticularly in a range of 5-200 ng / ml, even more particularly in a range of 10- 100 ng / ml, such as in a range of 15-50 ng / ml. As exemplified in the experi- mental section, FGF-7 may, for example, be present in an amount of about 25 ng / ml. Similarly, typical effective amounts of FGF-10 are in a range of 1- 10000 ng / ml, in particular in a range of 10-5000 ng / ml, more particularly in a range of 25-1000 ng / ml, such as in a range of 50-500 ng / ml As exempli- fied in the experimental section, FGF-10 may, for example, be present in an amount of about 100 ng / ml. (iii) a bone morphogenetic protein (BMP) antagonist. An example of such an an- tagonist is Noggin, and effective amounts of Noggin are typically in a range of 10-1000 ng / ml, in particular in a range of 25-500 ng / ml, more particu- larly in a range of 50-250 ng / ml. As exemplified in the experimental section, an effective amount may be, for example, at about 100 ng / ml. (iv) an ALK5 inhibitor. One example of anALK5 inhibitor is A83-01, which is typ- ically effective in a range of 1-10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, for example in a range of 100-1000 nM. As exemplified in the experimental section, an effective amount may be, for example, at about 500 nM. (v) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y- 27632. Typically, Y-27632 is effectively applied in a range of 0.01-50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM. As exemplified in the experimental section, an effective amount may be, for example, at about 5 µM. (vi) a p38 MAPK inhibitor. One example of a suitable p38 MAPK inhibitor is SB202190, which may be effectively applied in a range range of 1- 10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, such as in a range of 100-1000 nM. As exemplified in the ex- perimental section, an effective amount may be, for example, at about 500 nM. (vii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM. As exemplified in the experimental section, a suitable amount may be, for example, at about 5 mM. Optionally, the medium may additionally contain B27 supplement and N-acetylcysteine, such as about 1.25 mM N-acetylcysteine. Because of the medium used in growing the tumor organoids, substantially all tumor-associated immune cells are removed from the organoid. Further contemplated is the direct product of the above method, an ex vivo tumor organoid, obtained by the above-described method. Consequently, such a tumor organoid is characterized in that it is established from a cancer tissue sam- ple obtained from a tissue selected from the group consisting of lung, bronchus, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, renal pelvis, uterine corpus, oral cavity, or ovarian tissue. The tumor organoid may be established from a benign tumor, or a malignant cancer tumor. Wherein the tumor organoid is es- tablished from a malignant cancer tumor, the cancer may, for example, be selected from the group consisting of lung, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, renal, epithelial, or ovarian cancer. The tumor organoid may, in embodiments, be established from an adenocarcinoma, epidermoid carcinoma, and / or colorectal cancer. However, the sample may also be obtained from a cancer or from a tissue other than the above exemplified. In embodiments, the tumor or- ganoid is established from a subject, wherein the subject is a mammal; preferably a primate, such as a human; or a rodent such as a mouse, a rat, hamster or a guinea pig; or a cat, dog, sheep, horse or cow. In embodiments, the tumor organoid com- prises at least one mutation in a gene, optionally a gene associated with tumor resistance, in particular wherein the at least one mutation is a mutation in a gene selected from the group of genes comprising KRAS, EGFR, KEAP1, ALK, STK11, MET, TP53, ROS1, RB1, NOTCH1, NOTCH2, BRAF, NTRFK1 / 2 / 3, RET, ERBB2, HRAS, NRAS, ASCL1, NF1, PI3CA, FGFR1 / 2, MAP2K1, in particular from the group of genes con- sisting of KRAS, EGFR, KEAP1, ALK, and STK11. For example, the at least one muta- tion may be a mutation in KRAS. In case the subject is a human, the at least one mutation in KRAS may be a mutation at position Gly12 and / or Gln61, more specif- ically the at least one mutation may be a mutation in KRAS selected from GL12Ala, Gly12ASP, Gly12Val, Gly12Cys, and Gln61His. While tumor infiltrating lymphocytes (TILs) directly from surgical tis- sues have been previously used to study anti-tumor immunity, this does not ac- count for the systemic immune response and may miss critical interactions be- tween tumor cells and the immune system, thus not providing a complete picture of systemic immunotherapy responses. This obstacle is overcome in that the tumor organoids obtained after step (d) usually comprise substantially no tumor infiltrat- ing leukocytes. Instead, the tumor organoids can be used for mimicking activation of a systemic immune response. Simultaneously, the method uses tumor activated peripheral immune cells to provide enough relevant immune cells for a robust and repeatable screening system. Accordingly, further provided is an in vitro method of providing autolo- gous tumor organoid-activated immune cells, wherein the method comprises (a) establishing tumor organoids from a cancer tissue sample obtained from a subject according to the method as disclosed herein above; and (b) co-culturing the tumor organoids with immune cells obtained from said subject; thereby providing autologous tumor organoid-activated immune cells. Step (a) typically comprises isolating the tumor organoids from an ex- tracellular matrix gel comprising extracellular matrix proteins, such as laminin and collagen (e.g. as used in step (d) of the above-disclosed method). The tumor organ- oids are typically cultured in a culture medium, similar or identical to the medium used in the above-disclosed method for establishing tumor organoids. Accordingly, said culture medium preferably comprises at least two or more, preferably all, of the following (i)-(vii): (i) an inducer of the WNT / β catenin signalling pathway, such as R-spondin and / or WNT; for example R-spondin 1. R-spondin, such as R-spondin-1, may for example be present in an effective amount within a typical range of 1-10 000 ng / ml. Preferably, it may be present in a range of 10-5000 ng / ml, more preferably in a range of 100-2000 ng / ml, and even more preferably in a range of 250-1000 ng / ml. As exemplified in the experimental section, it may be present in an amount of about 500 ng / ml. (ii) FGF, for example FGF-7 and / or FGF-10, preferably both FGF-7 and FGF-10. Effective amounts for FGF-7 can be easily determined, and are typically in a range of 0.1-1000 ng / ml, in particular in a range of 1-500 ng / ml, more par- ticularly in a range of 5-200 ng / ml, even more particularly in a range of 10- 100 ng / ml, such as in a range of 15-50 ng / ml. As exemplified in the experi- mental section, FGF-7 may, for example, be present in an amount of about 25 ng / ml. Similarly, typical effective amounts of FGF-10 are in a range of 1- 10000 ng / ml, in particular in a range of 10-5000 ng / ml, more particularly in a range of 25-1000 ng / ml, such as in a range of 50-500 ng / ml As exempli- fied in the experimental section, FGF-10 may, for example, be present in an amount of about 100 ng / ml. (iii) a bone morphogenetic protein (BMP) antagonist. An example of such an an- tagonist is Noggin, and effective amounts of Noggin are typically in a range of 10-1000 ng / ml, in particular in a range of 25-500 ng / ml, more particu- larly in a range of 50-250 ng / ml. As exemplified in the experimental section, an effective amount may be, for example, at about 100 ng / ml. (iv) an ALK5 inhibitor. One example of anALK5 inhibitor is A83-01, which is typ- ically effective in a range of 1-10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, for example in a range of 100-1000 nM. As exemplified in the experimental section, an effective amount may be, for example, at about 500 nM. (v) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y- 27632. Typically, Y-27632 is effectively applied in a range of 0.01-50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM. As exemplified in the experimental section, an effective amount may be, for example, at about 5 µM. (vi) a p38 MAPK inhibitor. One example of a suitable p38 MAPK inhibitor is SB202190, which may be effectively applied in a range range of 1- 10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, such as in a range of 100-1000 nM. As exemplified in the ex- perimental section, an effective amount may be, for example, at about 500 nM. (vii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM. As exemplified in the experimental section, a suitable amount may be, for example, at about 5 mM. Optionally, the medium may additionally contain B27 supplement and N-acetylcysteine, such as about 1.25 mM N-acetylcysteine. One important aspect of the presently disclosed method vis-á-vis the prior art is that the immune cells applied in step (b) are obtained from the same subject from which the tumor organoids are established. Hence, tumor organoids and immune cells are autologous to each other. For example, the immune cells are isolated from whole blood, peripheral blood mononuclear cells (PBMCs), spleen, lymph nodes, buffy coats, pleural fluid, bone marrow aspirates, tumor and / or de- rived from induced pluripotent stem cells. In particular embodiments, the immune cells are peripheral immune cells, and in preferred embodiments the immune cells are PBMCs. Advantageously, the tumor organoids of step (a) are stimulated prior to step (b) such as to enhance antigen presentation. For example, this can e achieved by pre-cultivation in medium comprising type-II interferon, preferably IFN-ɣ. Typ- ically, type-II interferon, such as IFN-ɣ, is added in a range of 1 – 100000 ng / ml, in particular in a range of 10-10000 ng / ml, more particularly in a range of 50-5000 ng / ml, even more particularly in a range of 100-1000 ng / ml, such as in a range of 150-500 ng / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 200 ng / ml. Co-culturing in step (b) may comprise culturing in a culture medium, the culture medium comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2). The T cell growth fac- tor, such as IL-2, is typically added in a range of 1-100000 U / ml, in particu- lar in a range of 10-50000 U / ml, more particularly in a range of 50-10000 U / ml, still more particularly in a range of 100-1000 U / ml, such as in a range of 200-500 U / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 300 U / ml. (ii) an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 antibody. In embodiments, the anti-PD-1 / PD-L1 anti- body is selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezolizumab, Durvalumab, and Avelumab. In a particular em- bodiment exemplified herein below, the anti-PD-1 antibody is Nivolumab. Such an antibody may typically be added in a range of 0.1 – 1000 µg / ml, in particular in a range of 1-500 µg / ml, more particularly in a range of 5-250 µg / ml, even more particularly in a range of 10-100 µg / ml, such as in a range of 20-50 µg / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 40 µg / ml; and / or (iii) a T cell activating agent binding to CD28. For example, the medium may comprise an anti-CD28 antibody. Alternatively, stimulation by the anti-CD28 antibody may also be provided by pre-coating the anti-CD28 antibody to a surface of a cell culture vessel, such as a cell culture dish, a cell culture flask, or a cell culture bag, in which the culture medium is received, i.e. in which the co-culturing step is carried out. In step (b), dissociated tumor organoids and immune cells are typically combined in a ratio of tumor organoids : immune cells of 20:1, preferably added in equal volumes. Generally, step (b) is carried out for at least 5 days, preferably at least 7 days, more preferably at least 10 days. In particular embodiments, step (b) may be carried out for 14 days or more. In particular in the latter embodiment, tumor organoids are replaced with fresh tumor organoids after 5-7 days of co-cul- turing. As a result, the method of the present disclosure allows to produce autolo- gous activated immune cells, immune cells originating from the very same tumor patient, in an amount sufficient for a large-scale IO-drug screening system. As an intermediate product of the above method, further provided is an in vitro cell co-culture composition, comprising a tumor organoid established from a cancer tissue sample obtained from a subject as further disclosed herein above, and immune cells obtained from said subject. The immune cells may be immune cells isolated from peripheral blood mononuclear cells (PBMC), spleen, buffy coats, pleural fluid, bone marrow aspi- rates, tumor, and / or derived from stem cells preferably wherein the immune cells are peripheral immune cells, more preferably wherein the immune cells are PBMC. The co-culture typically further comprises a culture medium, comprising at least two or more, preferably all, of the following (i)-(iii): (i) a T cell growth factor, preferably interleukin 2 (IL-2). The T cell growth fac- tor, such as IL-2, is typically added in a range of 1-100000 U / ml, in particu- lar in a range of 10-50000 U / ml, more particularly in a range of 50-10000 U / ml, still more particularly in a range of 100-1000 U / ml, such as in a range of 200-500 U / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 300 U / ml. (ii) an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 antibody. In embodiments, the anti-PD-1 / PD-L1 anti- body is selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezolizumab, Durvalumab, and Avelumab. In a particular em- bodiment exemplified herein below, the anti-PD-1 antibody is Nivolumab. Such an antibody may typically be added in a range of 0.1 – 1000 µg / ml, in particular in a range of 1-500 µg / ml, more particularly in a range of 5-250 µg / ml, even more particularly in a range of 10-100 µg / ml, such as in a range of 20-50 µg / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 40 µg / ml. (iii) a T cell activating agent binding to CD28, preferably an anti-CD28 antibody. Alternatively, stimulation by the anti-CD28 antibody may also be provided by pre-coating the anti-CD28 antibody to a surface of a cell culture vessel, such as a cell culture dish, a cell culture flask, or a cell culture bag, in which the culture medium is received, i.e. in which the co-culture is present. The cell co-culture composition may comprise dissociated tumor organ- oids and immune cells in a ratio of tumor organoids:immune cells of 20:1. The present disclosure addresses the need for more real-life reflecting personalized human systemic immune cell context. Most prior models rely on tu- mor cell organoids without additional cells, tumor cell organoids with tumor-asso- ciated immune cells or non-autologous immune cells, mouse models that are not human and that are expensive as screening tools, and do not incorporate a blood vessel barrier into the system between the immune cells and the tumor organoids. In contrast, the system described herein includes tumor organoid -activated autol- ogous immune cells to mimic the patient’s systemic immune system; and also al- lows incorporation of blood vessel like structures between the organoids and the immune cells. To the knowledge of the present inventors, the present disclosure is the first one to combine a tumor organoid culture, for example a heterotypic tumor organoid comprising autologous fibroblasts, with autologous tumor organoid acti- vated immune cells, wherein the system can further include a blood-vessel mimicking barrier grown between the tumor organoids and the activated periph- eral immune cells. In certain embodiment, said physical boundary can also be made from autologous cells. The system is incorporated into a microfluidic context which allows easy, parallel measuring system for chemotaxis, tumor cell killing and im- mune cell activity status (e.g., by assaying cytokines or by flow cytometry). Accordingly, further provided is a method of preparing an in vitro organ culture system for mimicking tumor interaction with an immune system of a sub- ject, the method comprising: (i) providing a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which al- lows a cell to move from the first compartment to the second compartment; (ii) incorporating into the first compartment a three-dimensional tumor organ- oid established from a cancer tissue sample obtained from a subject, and a suitable tumor cell growth medium, and (iii) introducing into the second compartment autologous immune cells from said subject, which have been activated by co-culturing with said estab- lished tumor organoids, and a suitable immune cell growth medium; thereby providing the in vitro organ culture system. The physical boundary may, for example, be selected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary. For example, suitable examples of microfluidic chips providing such a boundary are described in WO 2022 / 167647. In a preferred em- bodiment, the tumor organoid was established from a cancer tissue sample ob- tained from a subject according to the method as described in detail herein above. Likewise, in a preferred embodiment, said autologous immune cells from said sub- ject have been activated by co-culturing with said established tumor organoids ac- cording to the method described herein above. The suitable tumor cell growth medium in step (ii) may be any suitable tumor cell growth medium. In preferred embodiments, however, it is a culture me- dium, which is suitable for culturing of tumor organoids, as described herein above. Hence, said medium comprises at least two or more, preferably all, of the following (i)-(vii): (i) an inducer of the WNT / β catenin signalling pathway, such as R-spondin and / or WNT; for example R-spondin 1. R-spondin, such as R-spondin-1, may for example be present in an effective amount within a typical range of 1-10 000 ng / ml. Preferably, it may be present in a range of 10-5000 ng / ml, more preferably in a range of 100-2000 ng / ml, and even more preferably in a range of 250-1000 ng / ml. As exemplified in the experimental section, it may be present in an amount of about 500 ng / ml. (ii) FGF, for example FGF-7 and / or FGF-10, preferably both FGF-7 and FGF-10. Effective amounts for FGF-7 can be easily determined, and are typically in a range of 0.1-1000 ng / ml, in particular in a range of 1-500 ng / ml, more par- ticularly in a range of 5-200 ng / ml, even more particularly in a range of 10- 100 ng / ml, such as in a range of 15-50 ng / ml. As exemplified in the experi- mental section, FGF-7 may, for example, be present in an amount of about 25 ng / ml. Similarly, typical effective amounts of FGF-10 are in a range of 1- 10000 ng / ml, in particular in a range of 10-5000 ng / ml, more particularly in a range of 25-1000 ng / ml, such as in a range of 50-500 ng / ml. As exem- plified in the experimental section, FGF-10 may, for example, be present in an amount of about 100 ng / ml. (iii) a bone morphogenetic protein (BMP) antagonist. An example of such an an- tagonist is Noggin, and effective amounts of Noggin are typically in a range of 10-1000 ng / ml, in particular in a range of 25-500 ng / ml, more particu- larly in a range of 50-250 ng / ml. As exemplified in the experimental section, an effective amount may be, for example, at about 100 ng / ml. (iv) an ALK5 inhibitor. One example of anALK5 inhibitor is A83-01, which is typ- ically effective in a range of 1-10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, for example in a range of 100-1000 nM. As exemplified in the experimental section, an effective amount may be, for example, at about 500 nM. (v) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y- 27632. Typically, Y-27632 is effectively applied in a range of 0.01-50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM. As exemplified in the experimental section, an effective amount may be, for example, at about 5 µM. (vi) a p38 MAPK inhibitor. One example of a suitable p38 MAPK inhibitor is SB202190, which may be effectively applied in a range range of 1- 10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, such as in a range of 100-1000 nM. As exemplified in the ex- perimental section, an effective amount may be, for example, at about 500 nM. (vii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM. As exemplified in the experimental section, a suitable amount may be, for example, at about 5 mM. Optionally, the medium may additionally contain B27 supplement and N-acetylcysteine, such as about 1.25 mM N-acetylcysteine. Typically, the tumor or- ganoids are incorporated in step (ii) using an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. Usually, the tumor or- ganoids are incorporated in step (ii) by seeding tumor cells in a density of 0.01- 50 x 103cells / µl, preferably in a range of 1-15 x 103cells / µl, more preferably in a range of 1-10 x 103cells / µl. In one advantageous embodiment, step (ii) further comprises incorpo- rating cancer-associated fibroblasts (CAF) obtained from said subject. For example, said fibroblasts may be seeded in a ratio tumor cells:CAF of about 1-8 : 1, preferably in a ratio of about 1-4 : 1. For example, they can be seeded at a density of 0.1-10 x 103cells / µl, such as at a density of about 0.5-2.5 x 103cells / µl. In one embodiment, after step (ii) autologous or non-autologous endo- thelial cells are incorporated on the tumor organoids, such as to mimick an endo- thelial blood vessel barrier. Suitable autologous endothelial cells are derived from the matching patient’s tumor, artery or veins, and suitable non-autologous endo- thelial cells are Human umbilical vein endothelial cells (HUVEC), Human lung mi- crovascular endothelial cells (HLMVEC), Human Pulmonary Microvascular endo- thelial cells (HPMEC), Human intestinal microvascular cells (HIMEC),. For example, the endothelial cells may be seeded in a density of 1-50 x 103cells / µl, such as at a density of about 7.5-10 x 103cells / µl. The immune cells are incorporated in step (iii) by seeding the immune cells in a density of 0.01-50 x 103 / µl, preferably in a range of 0.75-2 x 103cells / µl. As a result of the above method, further provided is an in vitro organ culture system for mimicking tumor interaction with an immune system of a sub- ject, comprising: (i) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second compartment; (ii) in the first compartment, a three-dimensional tumor organoid established from a cancer tissue sample obtained from the subject, and a suitable tumor cell growth medium, and (iii) in the second compartment, autologous immune cells from the subject, which have been activated by co-culturing with said established tumor or- ganoids, and a suitable immune cell growth medium. The physical boundary may, for example, be selected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based bound- ary, a basal membrane-based boundary, or a net-based boundary. In a preferred embodiment, the tumor organoid was established from a cancer tissue sample ob- tained from a subject according to the method as described in detail herein above. Likewise, in a preferred embodiment, said autologous immune cells from said sub- ject have been activated by co-culturing with said established tumor organoids ac- cording to the method described herein above. The suitable tumor cell growth medium may be any suitable tumor cell growth medium. In preferred embodiments, however, it is a culture medium, which is suitable for culturing of tumor organoids, as described herein above. Hence, said medium comprises at least two or more, preferably all, of the following (i)-(vii): (i) an inducer of the WNT / β catenin signalling pathway, such as R-spondin and / or WNT; for example R-spondin 1. R-spondin, such as R-spondin-1, may for example be present in an effective amount within a typical range of 1-10 000 ng / ml. Preferably, it may be present in a range of 10-5000 ng / ml, more preferably in a range of 100-2000 ng / ml, and even more preferably in a range of 250-1000 ng / ml. As exemplified in the experimental section, it may be present in an amount of about 500 ng / ml. (ii) FGF, for example FGF-7 and / or FGF-10, preferably both FGF-7 and FGF-10. Effective amounts for FGF-7 can be easily determined, and are typically in a range of 0.1-1000 ng / ml, in particular in a range of 1-500 ng / ml, more par- ticularly in a range of 5-200 ng / ml, even more particularly in a range of 10- 100 ng / ml, such as in a range of 15-50 ng / ml. As exemplified in the experi- mental section, FGF-7 may, for example, be present in an amount of about 25 ng / ml. Similarly, typical effective amounts of FGF-10 are in a range of 1- 10000 ng / ml, in particular in a range of 10-5000 ng / ml, more particularly in a range of 25-1000 ng / ml, such as in a range of 50-500 ng / ml As exempli- fied in the experimental section, FGF-10 may, for example, be present in an amount of about 100 ng / ml. (iii) a bone morphogenetic protein (BMP) antagonist. An example of such an an- tagonist is Noggin, and effective amounts of Noggin are typically in a range of 10-1000 ng / ml, in particular in a range of 25-500 ng / ml, more particularly in a range of 50-250 ng / ml. As exemplified in the experimental section, an effective amount may be, for example, at about 100 ng / ml. (iv) an ALK5 inhibitor. One example of anALK5 inhibitor is A83-01, which is typ- ically effective in a range of 1-10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, for example in a range of 100-1000 nM. As exemplified in the experimental section, an effective amount may be, for example, at about 500 nM. (v) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y- 27632. Typically, Y-27632 is effectively applied in a range of 0.01-50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM. As exemplified in the experimental section, an effective amount may be, for example, at about 5 µM. (vi) a p38 MAPK inhibitor. One example of a suitable p38 MAPK inhibitor is SB202190, which may be effectively applied in a range range of 1- 10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, such as in a range of 100-1000 nM. As exemplified in the ex- perimental section, an effective amount may be, for example, at about 500 nM. (vii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM. As exemplified in the experimental section, a suitable amount may be, for example, at about 5 mM. Optionally, the medium may additionally contain B27 supplement and N-acetylcysteine, such as about 1.25 mM N-acetylcysteine. Typically, the tumor or- ganoids are incorporated in step (ii) using an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. In embodiments, the first compartment further comprises cancer-asso- ciated fibroblasts (CAF) obtained from said subject. In further embodiments, the first compartment further comprises autologous or non-autologous endothelial cells, preferably wherein the the autologous endothelial cells are derived from the matching patient’s tumor, artery or veins, and preferably wherein the non-autolo- gous endothelial cells are Human umbilical vein endothelial cells (HUVEC), Human lung microvascular endothelial cells (HLMVEC), Human Pulmonary Microvascular endothelial cells (HPMEC), Human intestinal microvascular cells (HIMEC). In embodiments, the organ culture system comprises a microfluidic de- vice with at least two microfluidic channels, wherein each microfluidic channel comprises a different tumor organoid originating from different tumors in the same subject, and / or wherein at least one microfluidic channel comprises a second compartment without activated immune cells as a control. Typically, the first com- partment has a volume of 0.7 to 100 µl, preferably 0.7 to 80 µl, more preferably 0.7 to 50 µl, and even more preferably 0.7 to 10 µl, and most preferably 0.7 to 2 µl. Usually, the second compartment has a volume of 20 to 200 µl, preferably 20 to 100 µl, more preferably 20 to 50 µl, and most preferably 20 to 40 µl. The microfluidic channel may further comprise a media reservoir. During its application, the organ culture system may additionally com- prise one or more, preferably a combination of at least two immune-oncology drugs in the second compartment. In embodiments, at least one of the drugs is an immune checkpoint in- hibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD- L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 / PD-L1 anti- body. For example, an anti-PD-1 / PD-L1 antibody may be selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripal- imab, INCMGA00012, AMP-224, AMP-514, and Acrixolimab, Atezolizumab, Durval- umab, and Avelumab. For example, the anti-PD-1 antibody may be Nivolumab, as illustrated in the experimental section. The antibody may be added in typical amounts in a range of 0.1 – 1000 µg / ml, in particular in a range of 1-500 µg / ml, more particularly in a range of 5-250 µg / ml, even more particularly in a range of 10-150 µg / ml, such as at about 100 µg / ml. In further embodiments, at least one of the drugs is a chemotherapeutic agent and / or a small molecule. For example, the chemotherapeutic agent and / or small molecule may be selected from the group consisting of a EGFR tyrosine ki- nase inhibitor, a RAS GTPase inhibitor, a Lymphocyte activation gene-3 inhibitor, a folate antimetabolite, a TIM3 inhibitor, and a STING agonist. The EGFR tyrosine kinase inhibitor may be selected from the group con- sisting of Osimertinib, Gefitinib, Erlotinib, Afatinib, and EAI045, more particularly wherein the EGFR tyrosine kinase inhibitor is Osimertinib. Typically, the inhibitor is in an amount of 1-1000 nM, in particular in an amount of 10-500 nM, more par- ticularly in an amount of 50-250 nM, such as at about 100 nM. The RAS GTPase inhibitor may, for example, be selected from the group consisting of Sotorasib, Adagrasib, MRTX1133, MRTX849, RSC-1255, BI-1701963. For example, the RAS GTPase inhibitor may be Sotorasib. The inhibitor is typically applied in an amount of 1-1000 nM, in particular in an amount in the range of 100- 500 nM, such as at about 250 nM. An example for the Lymphocyte activation gene-3 inhibitor is Relat- limab. It may be added in an amount of 1-1000 µg / ml, in particular in a range of 5- 500 µg / ml, more particularly in a range of 10-100 µg / ml, such as at about 30 µg / ml. The folate antimetabolite can be selected from the group consisting of Pemetrexed and Methotrexate. For example, the folate antimetabolite may be Pemetrexed. It can be added in a typical amount of 0.1-100 µM, in particular in an amount of 0.5-50 µM, more particularly in an amount of 1-25 µM, such as in an amount of 2-10 µM. As exemplified in the experimental section, it may be added, for example, in an amount of about 2.5 µM. The chemotherapeutic agent may also be selected from the group con- sisting of Carboplatin, cis-platin, gemcitabine, nab-paclitaxel, paclitaxel, FOLFOX, and FOLFIRI. In embodiments, the chemotherapeutic agent is Carboplatin. The chemotherapeutic agent, such as carboplatin, can be added in a typical amount of 10-10000 µM, in particular in an amount of 50-5000 µM, such as in an amount of 100-500 µM. As exemplified in the experimental section, a suitable amount may be about 375 µM. The TIM3 inhibitor may, for example, be selected from Sabatolimab (MBG453), TSR022, Sym023, BGB-A425, AZD7789, RO7121661; and the STING ag- onist may be, for example, selected from DMXAA (Vadimezan), ADU-S100 (MIW815), Ulevostinag (MK-1454), BMS-986301, E7766, GSK3745417, and SB11285. Since the methods for establishing the tumor organoids and the autolo- gous tumor organoid activated immune cells allows the cells and organoids to be produced in high amounts, the methods advantageously allow to provide the iden- tical organ culture system to be provided in an increased quantity. Hence, in com- parison to the prior art, the present disclosure provides for the first time a plurality of the organ culture system as disclosed herein above, wherein said plurality com- prises at least 5, more preferably at least 10, even more preferably at least 20 organ culture systems. The plurality of the organ culture system allows conducting screening assays in large or larger scale. In accordance with the foregoing, further provided is a method for de- termining the responsiveness of a tumor to a treatment with at least one immune- oncologic drug, comprising the steps of (a) preparing an in vitro organ culture system according to the method as dis- closed herein above, or providing an in vitro organ culture system as dis- closed herein above; (b) adding one or more, preferably at least two immune-oncology drugs into the second compartment; and (c) determining the responsiveness of the in vitro organ culture system to the at least two immune-oncology drugs. For example, step c) may comprise determining the tumor cell growth and / or determining the viability of the tumor organoid cells in the first compart- ment, wherein a decreased tumor cell growth and / or a decreased viability is indic- ative for an effective response of the tumor to the treatment with said one or more immune-oncology drug. In embodiments, the tumor cell growth and / or determin- ing the viability of the tumor organoid cells in the first compartment is compared to the tumor cell growth and / or viability of the tumor organoid cells prior to step (b). Alternatively, the tumor cell growth and / or determining the viability of the tu- mor organoid cells in the first compartment may be compared to a control, in which control the immune cells are replaced by medium. Moreover, step (c) may also in- clude single cell sequencing to reveal which tumor cells have survived T cell medi- ated killing with the aid of immunotherapy. This would have the potential to accel- erate IO-drug development and guide treatment selection in the clinic. The analysis of the effects can readily be automated due to the microfluidic system. Accordingly, in one advantageous application, the method is repeated with a plurality of the same in vitro organ culture system as disclosed above for different immune-oncology drugs or combinations of different immune-oncology drugs, thereby identifying a personalized effective immune-oncology therapy for a patient. In addition or alternatively, the method is repeated with a plurality of the same in vitro organ culture system as disclosed herein above for different treat- ment regimens of an immune-oncology drug or drug combination, thereby identi- fying an effective treatment regimen. In another advantageous application, the method is repeated with a plu- rality of different in vitro organ culture system as further disclosed herein above for the same immune-oncology drug or with the same combination of immune-on- cology drugs, thereby identifying patient candidates who can benefit from treat- ment with said immune-oncology drug or said combination of immune-oncology drugs. In embodiments, at least one of the drugs in step (b) is an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 / PD- L1 antibody. For example, an anti-PD-1 / PD-L1 antibody may be selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripal- imab, INCMGA00012, AMP-224, AMP-514, and Acrixolimab, Atezolizumab, Durval- umab, and Avelumab. For example, the anti-PD-1 antibody may be Nivolumab, as illustrated in the experimental section. The antibody may be added in typical amounts in a range of 0.1 – 1000 µg / ml, in particular in a range of 1-500 µg / ml, more particularly in a range of 5-250 µg / ml, even more particularly in a range of 10-150 µg / ml, such as at about 100 µg / ml. In further embodiments, at least one of the drugs in step (b) is a chemo- therapeutic agent and / or a small molecule. For example, the chemotherapeutic agent and / or small molecule may be selected from the group consisting of a EGFR tyrosine kinase inhibitor, a RAS GTPase inhibitor, a Lymphocyte activation gene-3 inhibitor, a folate antimetabolite, a TIM3 inhibitor, and a STING agonist. The EGFR tyrosine kinase inhibitor may be selected from the group con- sisting of Osimertinib, Gefitinib, Erlotinib, Afatinib, and EAI045, more particularly wherein the EGFR tyrosine kinase inhibitor is Osimertinib. Typically, the inhibitor is in an amount of 1-1000 nM, in particular in an amount of 10-500 nM, more par- ticularly in an amount of 50-250 nM, such as at about 100 nM. The RAS GTPase inhibitor may, for example, be selected from the group consisting of Sotorasib, Adagrasib, MRTX1133, MRTX849, RSC-1255, BI-1701963. For example, the RAS GTPase inhibitor may be Sotorasib. The inhibitor is typically applied in an amount of 1-1000 nM, in particular in an amount in the range of 100- 500 nM, such as at about 250 nM. An example for the Lymphocyte activation gene-3 inhibitor is Relat- limab. It may be added in an amount of 1-1000 µg / ml, in particular in a range of 5- 500 µg / ml, more particularly in a range of 10-100 µg / ml, such as at about 30 µg / ml. The folate antimetabolite can be selected from the group consisting of Pemetrexed and Methotrexate. For example, the folate antimetabolite may be Pemetrexed. It can be added in a typical amount of 0.1-100 µM, in particular in an amount of 0.5-50 µM, more particularly in an amount of 1-25 µM, such as in an amount of 2-10 µM. As exemplified in the experimental section, it may be added, for example, in an amount of about 2.5 µM. The chemotherapeutic agent may also be selected from the group con- sisting of Carboplatin, cis-platin, gemcitabine, nab-paclitaxel, paclitaxel, FOLFOX, and FOLFIRI. In embodiments, the chemotherapeutic agent is Carboplatin. The chemotherapeutic agent, such as carboplatin, can be added in a typical amount of 10-10000 µM, in particular in an amount of 50-5000 µM, such as in an amount of 100-500 µM. As exemplified in the experimental section, a suitable amount may be about 375 µM. The TIM3 inhibitor may, for example, be selected from Sabatolimab (MBG453), TSR022, Sym023, BGB-A425, AZD7789, RO7121661; and the STING ag- onist may be, for example, selected from DMXAA (Vadimezan), ADU-S100 (MIW815), Ulevostinag (MK-1454), BMS-986301, E7766, GSK3745417, and SB11285. The Solid-IO platform also allows detecting biomarkers, such as cyto- kines, that promote or inhibit responses to drug combinations. Therefore, in em- bodiments, the method further comprises the step of comparing tumor organoids and / or culture medium in the first compartment of a responsive treatment to tu- mor organoids and / or culture medium in the first compartment of a non-respon- sive treatment, thereby identifying a biomarker for responsive or non-responsive treatment. For example, the comparison of phenotypic changes may comprise a comparison of cytokine levels in culture medium between a responsive treatment and a non-responsive treatment, in particular, wherein said biomarker is indicative for (i) a personalized effective or non-effective immune-oncology therapy for a pa- tient, (ii) an effective or non-effective treatment regimen, and / or (iii) a patient can- didate who can or cannot benefit from treatment with said immune-oncology drug or said combination of immune-oncology drugs, as outlined herein above. Finally, the present disclosure also provides a kit suitable for use in the above disclosed methods, such as a kit for preparing an in vitro organ culture sys- tem mimicking tumor interaction with an immune system of a subject. In embodi- ments, the kit comprising at least two, in particular at least three, more particularly at least four, even more particularly at least five, such as all of the following: (a)- : (a) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second compartment, as further disclosed herein above. In particular embodiments, the physical boundary is selected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary. (b) a tumor cell growth medium comprising at least two, preferably all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT; for example R-spondin 1. R-spondin, such as R-spon- din-1, may for example be present in an effective amount within a typi- cal range of 1-10000 ng / ml. Preferably, it may be present in a range of 10-5000 ng / ml, more preferably in a range of 100-2000 ng / ml, and even more preferably in a range of 250-1000 ng / ml. As exemplified in the experimental section, it may be present in an amount of about 500 ng / ml. (ii) FGF, for example FGF-7 and / or FGF-10, preferably both FGF-7 and FGF-10. Effective amounts for FGF-7 can be easily determined, and are typically in a range of 0.1-1000 ng / ml, in particular in a range of 1-500 ng / ml, more particularly in a range of 5-200 ng / ml, even more partic- ularly in a range of 10-100 ng / ml, such as in a range of 15-50 ng / ml. As exemplified in the experimental section, FGF-7 may, for example, be present in an amount of about 25 ng / ml. Similarly, typical effective amounts of FGF-10 are in a range of 1-10000 ng / ml, in particular in a range of 10-5000 ng / ml, more particularly in a range of 25-1000 ng / ml, such as in a range of 50-500 ng / ml As exemplified in the exper- imental section, FGF-10 may, for example, be present in an amount of about 100 ng / ml. (iii) a bone morphogenetic protein (BMP) antagonist. An example of such an antagonist is Noggin, and effective amounts of Noggin are typically in a range of 10-1000 ng / ml, in particular in a range of 25-500 ng / ml, more particularly in a range of 50-250 ng / ml. As exemplified in the ex- perimental section, an effective amount may be, for example, at about 100 ng / ml. (iv) an ALK5 inhibitor. One example of anALK5 inhibitor is A83-01, which is typically effective in a range of 1-10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, for exam- ple in a range of 100-1000 nM. As exemplified in the experimental sec- tion, an effective amount may be, for example, at about 500 nM. (v) a Rho kinase inhibitor. One example of a suitable Rho kinase inhibitor is Y-27632. Typically, Y-27632 is effectively applied in a range of 0.01- 50 µM, in particular in a range of 0.1-25 µM, more particularly in a range of 1-10 µM. As exemplified in the experimental section, an effec- tive amount may be, for example, at about 5 µM. (vi) a p38 MAPK inhibitor. One example of a suitable p38 MAPK inhibitor is SB202190, which may be effectively applied in a range range of 1- 10000 nM, in particular in a range of 10-5000 nM, more particularly in a range of 50-2500 nM, such as in a range of 100-1000 nM. As exempli- fied in the experimental section, an effective amount may be, for exam- ple, at about 500 nM. (c) an immune cell culture medium a culture medium, comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2). The T cell growth factor, such as IL-2, is typically added in a range of 1-100000 U / ml, in particular in a range of 10-50000 U / ml, more particularly in a range of 50-10000 U / ml, still more particularly in a range of 100- 1000 U / ml, such as in a range of 200-500 U / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 300 U / ml. (ii) an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 antibody. In embodiments, the anti-PD-1 / PD-L1 antibody is selected from Nivolumab, Pembroli- zumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spar- talizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezolizumab, Dur- valumab, and Avelumab. In a particular embodiment exemplified herein below, the anti-PD-1 antibody is Nivolumab. Such an antibody may typically be added in a range of 0.1 – 1000 µg / ml, in particular in a range of 1-500 µg / ml, more particularly in a range of 5-250 µg / ml, even more particularly in a range of 10-100 µg / ml, such as in a range of 20-50 µg / ml. As exemplified in the experimental section, suitable amounts may be, for example, at about 40 µg / ml. (iii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM. As exemplified in the experimental section, a suitable amount may be, for example, at about 5 mM. (d) a cell culture dish or cell culture container, which has been pre-coated with anti-CD28 antibody; (e) a container with IFN-ɣ; and / or (f) a container with an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. Further disclosed are the following embodiments: 1. An in vitro method of establishing tumor organoids from a cancer tissue sample obtained from a subject, the method comprising the steps of (a) dissociating the cancer tissue sample into cells and fragments; (b) propagating a first portion of the cells and / or fragments obtained in step (a) in a first 3D-culturing step; (c) propagating a second portion of the cells and / or fragments obtained in step (a) in a 2D-culturing step such as to enrich epithelial tumor cells and optionally fibroblasts; (d) combining the propagated cells and fragments obtained in step (b) with the propagated cells and fragments obtained in step (c), and propagating the combined cells and fragments in a second 3D-cultur- ing step; thereby establishing tumor organoids from the cancer tissue sample. 2. The method of embodiment 1, wherein the cancer tissue sample is a tissue sample obtained from a tissue selected from the group consisting of lung, bronchus, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, re- nal pelvis, uterine corpus, oral cavity, or ovarian tissue. 3. The method of embodiment 1 or 2, wherein the cancer tissue sample is a cancer tissue sample from a benign tumor. 4. The method of embodiment 1 or 2, wherein the cancer tissue sample is a cancer tissue sample from a malignant cancer tumor, in particular wherein the cancer is selected from the group consisting of lung, colon, rectal, pros- tate, breast, urinary bladder, thyroid, kidney, renal, epithelial, or ovarian cancer. 5. The method of any preceding embodiment, wherein the cancer tissue sam- ple is a cancer tissue sample from an adenocarcinoma, epidermoid carci- noma, and / or colorectal cancer. The method of any preceding embodiment, wherein the cancer tissue sam- ple is a cancer tissue sample from a cancer comprising at least one mutation in a gene, optionally a gene associated with tumor resistance, in particular wherein the at least one mutation is a mutation in a gene selected from the group of genes consisting of KRAS, EGFR, KEAP1, ALK, STK11, MET, TP53, ROS1, RB1, NOTCH1, NOTCH2, BRAF, NTRFK1 / 2 / 3, RET, ERBB2, HRAS, NRAS, ASCL1, NF1, PI3CA, FGFR1 / 2, MAP2K1, in particular from the group of genes consisting of KRAS, EGFR, KEAP1, ALK, and STK11. The method of embodiment 6, wherein the at least one mutation is a muta- tion in KRAS, in particular wherein the subject is a human and the at least one mutation in KRAS is a mutation at position Gly12 and / or Gln61, more specifically wherein the at least one mutation is a mutation in KRAS selected from GL12Ala, Gly12ASP, Gly12Val, Gly12Cys, and Gln61His. The method of any preceding embodiment, wherein the subject is a mam- mal; preferably a primate, such as a human; or a rodent such as a mouse, a rat, hamster or a guinea pig; or a cat, dog, sheep, horse or cow. The method of any preceding embodiment, wherein step (a) comprises us- ing mechanical and / or enzymatic means for dissociating the cancer tissue sample, in particular wherein the cancer tissue sample is minced, preferably into fragments of 1-2 mm3, and / or treated with enzymes, preferably with enzymes selected from the group consisting of collagenase, thermolysin, trypsin, hyaluronidase and papain, most preferably wherein the enzyme is collagenase. The method of any preceding embodiment, wherein step (b) is carried out in an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen, preferably wherein step (b) is carried out in Matrigel or Cultrex or Collagen. The method of any preceding embodiment, wherein step (b) comprises propagation in a culture medium comprising at least two or more, prefera- bly all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT, preferably R-spondin 1, in particular in a range of 1-10000 ng / ml, more preferably in a range of 10-5000 ng / ml, even more preferably in a range of 100-2000 ng / ml, still more preferably in a range of 250-1000 ng / ml, most preferably at about 500 ng / ml; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10, in particular wherein FGF-7 is in a range of 0.1-1000 ng / ml, more preferably in a range of 1-500 ng / ml, even more preferably in a range of 5-200 ng / ml, more preferably in a range of 10-100 ng / ml, still more preferably in a range of 15-50 ng / ml, and most preferably at about 25 ng / ml and / or in particular wherein FGF-10 is in a range of 1-10000 ng / ml, preferably in a range of 10-5000 ng / ml, even more preferably in a range of 25-1000 ng / ml, still more preferably in a range of 50-500 ng / ml, and most preferably at about 100 ng / ml; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin, in particular wherein Noggin is in a range of 10-1000 ng / ml, preferably in a range of 25-500 ng / ml, still more preferably in a range of 50-250 ng / ml, such as at about 100 ng / ml; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01, in particular wherein A83-01 is in a range 1-10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more preferably in a range of 1-10 µM, such as at about 5 µM; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190, in particular wherein SB202190 is in a range of 1- 10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (vii) nicotinamide, in particular in a range 0.1-100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM, such as at about 5 mM; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. The method of any preceding embodiment, wherein step (c) comprises propagation in a culture medium comprising at least two or more, prefera- bly all, of the following (i) FGF, preferably FGF-basic, in particular wherein FGF-basic is in a range of 0.1 – 10000 ng / ml, preferably in a range of 0.5-5000 ng / ml, even more preferably in a range of 1-1000 ng / ml, more preferably in a range of 5-500 ng / ml, still more preferably in a range of 10-50 ng / ml, and most preferably at about 20 ng / ml; (ii) EGF, in particular wherein EGF is in a range 0.1- 10000 ng / ml, pref- erably in a range of 0.5-5000 ng / ml, even more preferably in a range of 1-2000 ng / ml, even more preferably in a range of 2-1000 ng / ml, even more preferably in a range of 5-500 ng / ml, still more preferably in a range of 10-100 mg / ml, such as at about 50 ng / ml; (iii) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more preferably in a range of 1-10 µM, such as at about 5 µM; 13. The method of any preceding embodiment, wherein step (c) is carried out for at least 2-6 days, in particular for at least 4-6 days, and / or wherein step (d) is carried out no later than at passage 3, more particularly no later than at passage 2, in particular no later than at passage 1, such as at passage 0 of the epithelial tumor cells. 14. The method of any preceding embodiment, wherein step (c) further com- prises collecting and propagating cancer-associated fibroblasts, preferably in the same culture medium than the culture medium used in step (c). 15. The method of any preceding embodiment, wherein step (d) is carried out in an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen, preferably wherein step (d) is carried out in Matrigel or Cultrex. 16. The method of any preceding embodiment, wherein step (d) comprises propagation in a culture medium comprising at least two or more, prefera- bly all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT, preferably R-spondin 1, in particular in a range of 1-10000 ng / ml, more preferably in a range of 10-5000 ng / ml, even more preferably in a range of 100-2000 ng / ml, still more preferably in a range of 250-1000 ng / ml, most preferably at about 500 ng / ml; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10, in particular wherein FGF-7 is in a range of 0.1-1000 ng / ml, more preferably in a range of 1-500 ng / ml, even more preferably in a range of 5-200 ng / ml, more preferably in a range of 10-100 ng / ml, still more preferably in a range of 15-50 ng / ml, and most preferably at about 25 ng / ml and / or in particular wherein FGF-10 is in a range of 1-10000 ng / ml, preferably in a range of 10-5000 ng / ml, even more preferably in a range of 25-1000 ng / ml, still more preferably in a range of 50-500 ng / ml, and most preferably at about 100 ng / ml; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin, in particular wherein Noggin is in a range of 10-1000 ng / ml, preferably in a range of 25-500 ng / ml, still more preferably in a range of 50-250 ng / ml, such as at about 100 ng / ml; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01, in particular wherein A83-01 is in a range 1-10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more preferably in a range of 1-10 µM, such as at about 5 µM; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190, in particular wherein SB202190 is in a range of 1- 10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (vii) nicotinamide, in particular in a range of 0.1 – 100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM, such as at about 5 mM; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. 17. The method of any preceding embodiment, wherein step (d) comprises propagation in a culture medium which is the same than the culture me- dium used in step (b). 18. The method of any preceding step, wherein the tumor organoids obtained after step (d) comprise substantially no tumor infiltrating leukocytes. An in vitro method of providing autologous tumor organoid-activated im- mune cells, wherein the method comprises (a) establishing tumor organoids from a cancer tissue sample obtained from a subject according to the method of any one of embodiments 1-19; and (b) co-culturing the tumor organoids with immune cells obtained from said subject; thereby providing autologous tumor organoid-activated immune cells. The method of embodiment 19, wherein step (a) comprises isolating the tu- mor organoids from an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. The method of embodiment 19 or embodiment 20, wherein step (a) com- prises culturing the tumor organoids in a culture medium, comprising at least two or more, preferably all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT, preferably R-spondin 1, in particular in a range of 1-10000 ng / ml, more preferably in a range of 10-5000 ng / ml, even more preferably in a range of 100-2000 ng / ml, still more preferably in a range of 250-1000 ng / ml, most preferably at about 500 ng / ml; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10, in particular wherein FGF-7 is in a range of 0.1-1000 ng / ml, more preferably in a range of 1-500 ng / ml, even more preferably in a range of 5-200 ng / ml, more preferably in a range of 10-100 ng / ml, still more preferably in a range of 15-50 ng / ml, and most preferably at about 25 ng / ml and / or in particular wherein FGF-10 is in a range of 1-10000 ng / ml, preferably in a range of 10-5000 ng / ml, even more preferably in a range of 25-1000 ng / ml, still more preferably in a range of 50-500 ng / ml, and most preferably at about 100 ng / ml; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin, in particular wherein Noggin is in a range of 10-1000 ng / ml, preferably in a range of 25-500 ng / ml, still more preferably in a range of 50-250 ng / ml, such as at about 100 ng / ml; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01, in particular wherein A83-01 is in a range 1-10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more preferably in a range of 1-10 µM, such as at about 5 µM; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190, in particular wherein SB202190 is in a range of 1- 10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (vii) nicotinamide, in particular in a range of 0.1 – 100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM, such as at about 5 mM; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. 22. The method of any one of embodiments 19-21, wherein the immune cells are immune cells isolated from whole blood, peripheral blood mononuclear cells (PBMCs), spleen, lymph nodes, buffy coats, pleural fluid, bone marrow aspirates, tumor, and / or derived from induced pluripotent stem cells, pref- erably wherein the immune cells are peripheral immune cells, more prefera- bly wherein the immune cells are PBMCs. 23. The method of any one of embodiments 19-22, wherein the tumor organ- oids of step (a) are stimulated prior to step (b) such as to enhance antigen presentation, in particular by pre-cultivation in medium comprising type-II interferon, preferably IFN-ɣ, preferably added in a range of 1 – 100000 ng / ml, more preferably in a range of 10-10000 ng / ml, even more prefera- bly in a range of 50-5000 ng / ml, still more preferably 100-1000 ng / ml, still even more preferably 150-500 ng / ml, such as at about 200 ng / ml. 24. The method of any one of embodiments 19-23, wherein step (b) comprises co-culturing in a culture medium, the culture medium comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2), preferably added in a range of 1-100000 U / ml, more preferably in a range of 10-50000 U / ml, even more preferably in a range of 50-10000 U / ml, still more preferably in a range of 100-1000 U / ml, still even more preferably in a range of 200-500 U / ml, such as at about 300 U / ml; and / or (ii) an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 antibody, anti-CTLA4 antibody, more preferably anti PD-1 antibody, in particular an anti-PD-1 anti- body selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camreli- zumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP- 224, AMP-514, Acrixolimab, Atezolizumab, Durvalumab, and Avelumab, more preferably wherein the anti-PD-1 antibody is Nivolumab, in particular added in a range of 0.1 – 1000 µg / ml, pref- erably in a range of 1-500 µg / ml, more preferably in a range of 5-250 µg / ml, still even more preferably in a range of 10-100 µg / ml, even more preferably in a range of 20-50 µg / ml, such as at about 40 µg / ml; and / or (iii) a T cell activating agent binding to CD28, preferably an anti-CD28 an- tibody, or wherein the anti-CD28 antibody has been pre-coated to a surface of a cell culture vessel in which the culture medium is received. 25. The method of any one of embodiments 19-24, wherein in step (b) dissoci- ated tumor organoids and immune cells are combined in a ratio of tumor or- ganoids:immune cells of 20:1, preferably added in equal volumes. 26. The method of any one of embodiments 19-25, wherein step (b) is carried out for at least 5 days, preferably at least 7 days, more preferably at least 10 days, and in particular for 14 days or more. 27. The method of any one of embodiments 19-26, wherein in step (b) tumor organoids are replaced with fresh tumor organoids after 5-7 days of co-cul- turing. 28. A method of preparing an in vitro organ culture system for mimicking tumor interaction with an immune system of a subject, the method comprising: (i) providing a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second compartment in particular wherein the physical boundary is selected from a mem- brane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary; (ii) incorporating into the first compartment a three-dimensional tumor organoid established from a cancer tissue sample obtained from a subject, and a suitable tumor cell growth medium, and (iii) introducing into the second compartment autologous immune cells from said subject, which have been activated by co-culturing with said established tumor organoids, and a suitable immune cell growth medium; thereby providing the in vitro organ culture system. The method of embodiment 28, wherein the tumor organoid was estab- lished from a cancer tissue sample obtained from a subject according to the method of any one of embodiments 1-19. The method of embodiment 28 or embodiment 29, wherein the suitable tu- mor cell growth medium in step (ii) comprises at least two or more, prefera- bly all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT, preferably R-spondin 1, in particular in a range of 1-10000 ng / ml, more preferably in a range of 10-5000 ng / ml, even more preferably in a range of 100-2000 ng / ml, still more preferably in a range of 250-1000 ng / ml, most preferably at about 500 ng / ml; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10, in particular wherein FGF-7 is in a range of 0.1-1000 ng / ml, more preferably in a range of 1-500 ng / ml, even more preferably in a range of 5-200 ng / ml, more preferably in a range of 10-100 ng / ml, still more preferably in a range of 15-50 ng / ml, and most preferably at about 25 ng / ml and / or in particular wherein FGF-10 is in a range of 1-10000 ng / ml, preferably in a range of 10-5000 ng / ml, even more preferably in a range of 25-1000 ng / ml, still more preferably in a range of 50-500 ng / ml, and most preferably at about 100 ng / ml; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin, in particular wherein Noggin is in a range of 10-1000 ng / ml, preferably in a range of 25-500 ng / ml, still more preferably in a range of 50-250 ng / ml, such as at about 100 ng / ml; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01, in particular wherein A83-01 is in a range 1-10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more preferably in a range of 1-10 µM, such as at about 5 µM; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190, in particular wherein SB202190 is in a range of 1- 10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (vii) nicotinamide, in particular in a range of 0.1 – 100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM, such as at about 5 mM; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. 31. The method of any one of embodiments 28-30, wherein the tumor organ- oids are incorporated in step (ii) using an extracellular matrix gel, compris- ing extracellular matrix proteins, such as laminin and collagen. 32. The method of any one of embodiments 28-31, wherein the tumor organ- oids are incorporated in step (ii) by seeding tumor cells in a density of 0.01- 50 x 103cells / µl, preferably in a range of 1-15 x 103cells / µl, more prefera- bly in a range of 1-10 x 103cells / µl. 33. The method of any one of embodiments 28-32, wherein said autologous im- mune cells from said subject have been activated by co-culturing with said established tumor organoids according to the method of any one of embodi- ments 20-27. 34. The method of any one of embodiments 28-33, wherein the immune cells are incorporated in step (iii) by seeding the immune cells in a density of 0.01-50 x 103 / µl, preferably in a range of 0.75-2 x 103cells / µl. 35. The method of any one of embodiments 28-34, wherein step (ii) further comprises incorporating cancer-associated fibroblasts (CAF) obtained from said subject, preferably wherein said fibroblasts are seeded in a ratio tumor cells:CAF of about 1-8 : 1, preferably in a ratio of about 1-4 : 1, more prefera- bly at a density of 0.1-10 x 103cells / µl, such as at a density of about 0.5-2.5 x 103cells / µl. 36. The method of any one of embodiments 28-35, wherein after step (ii) autol- ogous or non-autologous endothelial cells are incorporated on the tumor or- ganoids, preferably wherein the autologous endothelial cells are derived from the matching patient’s tumor, artery or veins, and non-autologous en- dothelial cells are Human umbilical vein endothelial cells (HUVEC), Human lung microvascular endothelial cells (HLMVEC), Human Pulmonary Micro- vascular endothelial cells (HPMEC), Human intestinal microvascular cells (HIMEC), more preferably wherein the endothelial cells are seeded in a den- sity of 1-50 x 103cells / µl, such as at a density of about 7.5-10 x 103cells / µl. 37. An ex vivo tumor organoid, obtained by the method according to embodi- ments 1-18. 38. The tumor organoid of embodiment 37, wherein the tumor organoid is es- tablished from a cancer tissue sample obtained from a tissue selected from the group consisting of lung, bronchus, colon, rectal, prostate, breast, uri- nary bladder, thyroid, kidney, renal pelvis, uterine corpus, oral cavity, or ovarian tissue. 39. The tumor organoid of embodiment 37 or 38, wherein the tumor organoid is established from a benign tumor. 40. The tumor organoid of embodiment 37 or 38, wherein the tumor organoid is established from a malignant cancer tumor, in particular wherein the cancer is selected from the group consisting of lung, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, renal, epithelial, or ovarian cancer. 41. The tumor organoid of embodiment 37-40, wherein the tumor organoid is established an adenocarcinoma, epidermoid carcinoma, and / or colorectal cancer. 42. The tumor organoid of embodiment 37-41, wherein the tumor organoid comprises at least one mutation in a gene, optionally a gene associated with tumor resistance, in particular wherein the at least one mutation is a muta- tion in a gene selected from the group of genes consisting of KRAS, EGFR, KEAP1, ALK, and STK11. 43. The tumor organoid of embodiment 42, wherein the at least one mutations is a mutation in KRAS, in particular wherein the subject is a human and the at least one mutation in KRAS is a mutation at position Gly12 and / or Gln61, more specifically wherein the at least one mutation is a mutation in KRAS se- lected from GL12Ala, Gly12ASP, Gly12Val, Gly12Cys, and Gln61His. The tumor organoid of embodiment 37-42, wherein the tumor organoid is established from a subject, wherein the subject is a mammal; preferably a primate, such as a human; or a rodent such as a mouse, a rat, hamster or a guinea pig; or a cat, dog, sheep, horse or cow. An in vitro cell co-culture composition, comprising a tumor organoid estab- lished from a cancer tissue sample obtained from a subject as further de- fined in any one of embodiments 37-44, and immune cells obtained from said subject. The cell co-culture composition of embodiment 45, wherein the immune cells are immune cells isolated from peripheral blood mononuclear cells (PBMC), spleen, buffy coats, pleural fluid, bone marrow aspirates, tumor, and / or derived from induced pluripotent stem cells, preferably wherein the immune cells are peripheral immune cells, more preferably wherein the im- mune cells are PBMC. The cell co-culture composition of embodiment 45 or 46, further comprising a culture medium, comprising at least two or more, preferably all, of the fol- lowing (i) a T cell activating agent binding to CD28, preferably an anti-CD28 an- tibody; (ii) a T cell growth factor, preferably interleukin 2 (IL-2), preferably added in a range of 1-100000 U / ml, more preferably in a range of 10-50000 U / ml, even more preferably in a range of 50-10000 U / ml, still more preferably in a range of 100-1000 U / ml, still even more preferably in a range of 200-500 U / ml, such as at about 300 U / ml; and / or (iii) an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 / PD-L1 antibody, in particular an anti-PD-1 / PD-L1 antibody selected from Nivolumab, Pembroli- zumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spar- talizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, and Acrixolimab, more prefera- bly wherein the anti-PD-1 antibody is Nivolumab, in particular added in a range of 0.1 – 1000 µg / ml, preferably in a range of 1-500 µg / ml, more preferably in a range of 5-250 µg / ml, still even more preferably in a range of 10-100 µg / ml, even more preferably in a range of 20-50 µg / ml, such as at about 40 µg / ml. The cell co-culture composition of any one of embodiments 45-47, compris- ing dissociated tumor organoids and immune cells in a ratio of tumor organ- oids:immune cells of 20:1. An in vitro organ culture system for mimicking tumor interaction with an immune system of a subject, comprising: (i) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second com- partment, in particular wherein the physical boundary is selected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary; (ii) in the first compartment, a three-dimensional tumor organoid estab- lished from a cancer tissue sample obtained from the subject, and a suitable tumor cell growth medium, and (iii) in the second compartment, autologous immune cells from the sub- ject, which have been activated by co-culturing with said established tumor organoids, and a suitable immune cell growth medium. The organ culture system of embodiment 49, wherein the tumor organoid is a tumor organoid according to embodiments 37-44. The organ culture system of embodiment 49 or 50, wherein the suitable tu- mor cell growth medium in step (ii) comprises at least two or more, prefera- bly all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spon- din and / or WNT, preferably R-spondin 1, in particular in a range of 1-10000 ng / ml, more preferably in a range of 10-5000 ng / ml, even more preferably in a range of 100-2000 ng / ml, still more preferably in a range of 250-1000 ng / ml, most preferably at about 500 ng / ml; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10, in particular wherein FGF-7 is in a range of 0.1-1000 ng / ml, more preferably in a range of 1-500 ng / ml, even more preferably in a range of 5-200 ng / ml, more preferably in a range of 10-100 ng / ml, still more preferably in a range of 15-50 ng / ml, and most preferably at about 25 ng / ml and / or in particular wherein FGF-10 is in a range of 1-10000 ng / ml, preferably in a range of 10-5000 ng / ml, even more preferably in a range of 25-1000 ng / ml, still more preferably in a range of 50-500 ng / ml, and most preferably at about 100 ng / ml; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin, in particular wherein Noggin is in a range of 10-1000 ng / ml, preferably in a range of 25-500 ng / ml, still more preferably in a range of 50-250 ng / ml, such as at about 100 ng / ml; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01, in particular wherein A83-01 is in a range 1-10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more preferably in a range of 1-10 µM, such as at about 5 µM; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190, in particular wherein SB202190 is in a range of 1- 10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (vii) nicotinamide, in particular in a range of 0.1 – 100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM, such as at about 5 mM; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. 52. The organ culture system of any one of embodiment 49-51, wherein the tu- mor organoids are incorporated in an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. 53. The organ culture system of any one of embodiment 49-52, wherein the first compartment further comprises cancer-associated fibroblasts (CAF) ob- tained from said subject. 54. The organ culture system of any one of embodiment 49-53, wherein the first compartment further comprises an endothelial tubule formed by autologous or non-autologous endothelial cells, preferably wherein the autologous en- dothelial cells are derived from the matching patient’s tumor, artery or veins, and preferably wherein the non-autologous endothelial cells are Hu- man umbilical vein endothelial cells (HUVEC), Human lung microvascular endothelial cells (HLMVEC), Human Pulmonary Microvascular endothelial cells (HPMEC), Human intestinal microvascular cells (HIMEC). 55. The organ culture system of any one of embodiment 49-54, comprising a mi- crofluidic device with at least two microfluidic channels, wherein each mi- crofluidic channel comprises a different tumor organoid originating from different tumors in the same subject, and / or wherein at least one microflu- idic channel comprises a second compartment without activated immune cells as a control. 56. The organ culture system of any one of embodiment 49-55, wherein the first compartment has a volume of 0.7 to 100 µl, preferably 0.7 to 80 µl, more preferably 0.7 to 50 µl, and even more preferably 0.7 to 10 µl, and most pref- erably 0.7 to 2 µl. 57. The organ culture system of any one of embodiment 49-56, wherein the sec- ond compartment has a volume of 20 to 200 µl, preferably 20 to 100 µl, more preferably 20 to 50 µl, and most preferably 20 to 40 µl. 58. The organ culture system of any one of embodiment 49-57, wherein the mi- crofluidic channel further comprises a media reservoir. 59. The organ culture system of any one of embodiment 49-58, wherein the sec- ond compartment additionally comprises one or more, preferably at least two immune-oncology drugs. 60. The organ culture system of embodiment 59, wherein at least one of the drugs is an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 anti- body, more preferably anti PD-1 / PD-L1 antibody, in particular an anti-PD- 1 / PD-L1 antibody selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, and Acrixolimab, Atezolizumab, Durvalumab, and Avelumab, more prefera- bly wherein the anti-PD-1 antibody is Nivolumab, in particular added in a range of 0.1 – 1000 µg / ml, preferably in a range of 1-500 µg / ml, more pref- erably in a range of 5-250 µg / ml, even more preferably in a range of 10-150 µg / ml, such as at about 100 µg / ml. The organ culture system of embodiment 59 or 60, wherein at least one of the drugs is a chemotherapeutic agent and / or a small molecule, preferably wherein the chemotherapeutic agent and / or small molecule is selected from the group consisting of a EGFR tyrosine kinase inhibitor, a RAS GTPase inhibitor, a Lymphocyte activation gene-3 inhibitor, a folate an- timetabolite, a TIM3 inhibitor, and a STING agonist; in particular wherein the EGFR tyrosine kinase inhibitor is selected from the group consisting of Osimertinib, Gefitinib, Erlotinib, Afatinib, and EAI045, more particularly wherein the EGFR tyrosine kinase inhibitor is Osimer- tinib, even more particularly in an amount of 1-1000 nM, preferably in an amount of 10-500 nM, more preferably in an amount of 50-250 nM, such as at about 100 nM; and / or in particular wherein the RAS GTPase inhibitor is selected from the group consisting of Sotorasib, Adagrasib, MRTX1133, MRTX849, RSC-1255, BI- 1701963, more particularly wherein the RAS GTPase inhibitor is Sotorasib, even more particularly added in an amount of 1-1000 nM, preferably 100- 500 nM, such as at about 250 nM; and / or in particular wherein the Lymphocyte activation gene-3 inhibitor is Relat- limab, even more particularly in an amount of 1-1000 µg / ml preferably in a range of 5-500 µg / ml, more preferably in a range of 10-100 µg / ml, such as at about 30 µg / ml; and / or in particular wherein the folate antimetabolite is selected from the group consisting of Pemetrexed and Methotrexate, more particularly wherein the folate antimetabolite is Pemetrexed, even more particularly added in an amount of 0.1-100 µM, preferably in an amount of 0.5-50 µM, more prefera- bly in an amount of 1-25 µM, even more preferably in an amount of 2-10 µM, such as at about 2.5 µM; and / orin particular wherein the chemotherapeutic agent is selected from the group consisting of Carboplatin, cis-platin, gem- citabine, nab-paclitaxel, paclitaxel, FOLFOX, and FOLFIRI, more particularly wherein the chemotherapeutic agent is Carboplatin, even more particularly added in an amount of 10-10000 µM, preferably in an amount of 50-5000 µM, more preferably in an amount of 100-500 µM, such as at about 375 µM; in particular wherein the TIM3 inhibitor is selected from Sabatolimab (MBG453), TSR022, Sym023, BGB-A425, AZD7789, RO7121661; and in particular wherein the STING agonist is selected from DMXAA (Va- dimezan), ADU-S100 (MIW815), Ulevostinag (MK-1454), BMS-986301, E7766, GSK3745417, and SB11285. 62. A plurality of the organ culture system according to any one of embodi- ments 49-61, preferably according to embodiments 49 to 58, wherein said plurality comprises at least 5, more preferably at least 10, even more prefer- ably at least 20 organ culture system according to any one of embodiments 49-61, preferably according to embodiments 49 to 58. 63. A method for determining the responsiveness of a tumor to a treatment with at least one immune-oncologic drug, comprising the steps of (a) preparing an in vitro organ culture system according to the method of any one of embodiments 28-36, or providing an in vitro organ culture system according to any one of embodiments 49-58; (b) adding one or more, preferably at least two immune-oncology drugs into the second compartment; and (c) determining the responsiveness of the in vitro organ culture system to the at least two immune-oncology drugs. 64. The method of embodiment 63, wherein step c) comprises determining the tumor cell growth and / or determining the viability of the tumor organoid cells in the first compartment, wherein a decreased tumor cell growth and / or a decreased viability is indicative for an effective response of the tu- mor to the treatment with said one or more immune-oncology drug. 65. The method of embodiment 64, wherein the tumor cell growth and / or de- termining the viability of the tumor organoid cells in the first compartment is compared to the tumor cell growth and / or viability of the tumor organoid cells prior to step (b); or wherein the tumor cell growth and / or determining the viability of the tu- mor organoid cells in the first compartment is compared to a control, in which control the immune cells are replaced by medium. 66. The method of any one of embodiments 63-65, wherein the method is re- peated with a plurality of the same in vitro organ culture system according to any one of embodiments 49-58 for different immune-oncology drugs or combinations of different immune-oncology drugs, thereby identifying a personalized effective immune-oncology therapy for a patient. 67. The method of any one of embodiments 63-65, wherein the method is re- peated with a plurality of the same in vitro organ culture system according to any one of embodiments 49-58 for different treatment regimens of an im- mune-oncology drug or drug combination, thereby identifying an effective treatment regimen. 68. The method of any one of embodiments 63-65, wherein the method is re- peated with a plurality of different in vitro organ culture system according to any one of embodiments 49-58 for the same immune-oncology drug or with the same combination of immune-oncology drugs, thereby identifying patient candidates who can benefit from treatment with said immune-oncol- ogy drug or said combination of immune-oncology drugs. 69. The method of any one of embodiments 63-68, wherein at least one of the drugs of step (b) is an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti- CTLA4 antibody, more preferably anti PD-1 / PD-L1 antibody, in particular an anti-PD-1 / PD-L1 antibody selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP- 224, AMP-514, and Acrixolimab, Atezolizumab, Durvalumab, and Avelumab, more preferably wherein the anti-PD-1 antibody is Nivolumab, in particular added in a range of 0.1 – 1000 µg / ml, preferably in a range of 1-500 µg / ml, more preferably in a range of 5-250 µg / ml, even more preferably in a range of 10-150 µg / ml, such as at about 100 µg / ml. 70. The method of any one of embodiments 63-69, wherein at least one of the drugs is a chemotherapeutic agent, a small molecule, and / or an anti-cancer agent, other than an immune checkpoint inhibitor, preferably wherein the chemotherapeutic agent and / or small molecule is selected from the group consisting of a EGFR tyrosine kinase inhibitor, a RAS GTPase inhibitor, a Lymphocyte activation gene-3 inhibitor, a folate an- timetabolite, a TIM3 inhibitor, and a STING agonist; in particular wherein the EGFR tyrosine kinase inhibitor is selected from the group consisting of Osimertinib, Gefitinib, Erlotinib, Afatinib, and EAI045, more particularly wherein the EGFR tyrosine kinase inhibitor is Osimer- tinib, even more particularly in an amount of 1-1000 nM, preferably in an amount of 10-500 nM, more preferably in an amount of 50-250 nM, such as at about 100 nM; and / or in particular wherein the RAS GTPase inhibitor is selected from the group consisting of Sotorasib, Adagrasib, MRTX1133, MRTX849, RSC-1255, BI- 1701963, more particularly wherein the RAS GTPase inhibitor is Sotorasib, even more particularly added in an amount of 1-1000 nM, preferably 100- 500 nM, such as at about 250 nM; and / or in particular wherein the Lymphocyte activation gene-3 inhibitor is selected from the group consisting of Relatlimab, [please extend, if useful], more par- ticularly wherein the Lymphocyte activation gene-3 inhibitor is Relatlimab, even more particularly in an amount of 1-1000 µg / ml such as at about 30 µg / ml; and / or in particular wherein the folate antimetabolite is selected from the group consisting of Pemetrexed and Methotrexate, more particularly wherein the folate antimetabolite is Pemetrexed, even more particularly added in an amount of 0.1-100 µM, preferably in an amount of 0.5-50 µM, more prefera- bly in an amount of 1-25 µM, even more preferably in an amount of 2-10 µM, such as at about 2.5 µM; and / or in particular wherein the chemotherapeutic agent is selected from the group consisting of Carboplatin, cis-platin, gemcitabine, nab-paclitaxel, paclitaxel, FOLFOX, and FOLFIRI, more particularly wherein the chemotherapeutic agent is Carboplatin, even more particularly added in an amount of 10-10 000 µM, preferably in an amount of 50-5000 µM, more preferably in an amount of 100-500 µM, such as at about 375 µM; in particular wherein the TIM3 inhibitor is selected from Sabatolimab (MBG453), TSR022, Sym023, BGB-A425, AZD7789, RO7121661; and in particular wherein the STING agonist is selected from DMXAA (Va- dimezan), ADU-S100 (MIW815), Ulevostinag (MK-1454), BMS-986301, E7766, GSK3745417, and SB11285. The method of any one of embodiments 63-70, further comprising the step of comparing tumor organoids and / or culture medium in the first compart- ment of a responsive treatment to tumor organoids and / or culture medium in the first compartment of a non-responsive treatment, thereby identifying a biomarker for responsive or non-responsive treatment. The method of embodiment 71, wherein the comparison of phenotypic changes comprises a comparison of cytokine levels in culture medium be- tween a responsive treatment and a non-responsive treatment, in particular, wherein said biomarker is indicative for (i) a personalized effective or non- effective immune-oncology therapy for a patient, (ii) an effective or non-ef- fective treatment regimen, and / or (iii) a patient candidate who can or cannot benefit from treatment with said immune-oncology drug or said combination of immune-oncology drugs. A kit for preparing an in vitro organ culture system mimicking tumor inter- action with an immune system of a subject, the kit comprising at least two, preferably at least three, more preferably at least four, even more preferably at least five, and most preferably all of the following: (a) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second com- partment, in particular wherein the physical boundary is selected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary; (b) a tumor cell growth medium comprising at least two, preferably all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R- spondin and / or WNT, preferably R-spondin 1, in particular in a range of 1-10000 ng / ml, more preferably in a range of 10-5000 ng / ml, even more preferably in a range of 100-2000 ng / ml, still more preferably in a range of 250-1000 ng / ml, most preferably at about 500 ng / ml; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10, in particular wherein FGF-7 is in a range of 0.1- 1000 ng / ml, more preferably in a range of 1-500 ng / ml, even more preferably in a range of 5-200 ng / ml, more preferably in a range of 10-100 ng / ml, still more preferably in a range of 15-50 ng / ml, and most preferably at about 25 ng / ml and / or in partic- ular wherein FGF-10 is in a range of 1-10000 ng / ml, preferably in a range of 10-5000 ng / ml, even more preferably in a range of 25-1000 ng / ml, still more preferably in a range of 50-500 ng / ml, and most preferably at about 100 ng / ml; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin, in particular wherein Noggin is in a range of 10-1000 ng / ml, preferably in a range of 25-500 ng / ml, still more preferably in a range of 50-250 ng / ml, such as at about 100 ng / ml; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01, in particular wherein A83-01 is in a range of 1-10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100- 1000 nM, such as at about 500 nM; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase in- hibitor is Y-27632, in particular wherein Y-27632 is in a range of 0.01-50 µM, preferably in a range of 0.1-25 µM, more prefera- bly in a range of 1-10 µM, such as at about 5 µM; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhib- itor is SB202190, in particular wherein SB202190 is in a range of 1- 10000 nM, preferably in a range of 10-5000 nM, more preferably in a range of 50-2500 nM, still more preferably in a range of 100-1000 nM, such as at about 500 nM; (c) an immune cell culture medium a culture medium, comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2), preferably added in a range of 1-100000 U / ml, more preferably in a range of 10-50000 U / ml, even more preferably in a range of 50-10000 U / ml, still more preferably in a range of 100-1000 U / ml, still even more preferably in a range of 200-500 U / ml, such as at about 300 U / ml; (ii) an immune checkpoint inhibitor, preferably an immune check- point inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 / PD-L1 anti- body, in particular an anti-PD-1 / PD-L1 antibody selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Retifan- limab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezolizumab, Durvalumab, and Avelumab, more preferably wherein the anti-PD-1 antibody is Nivolumab, in par- ticular added in a range of 0.1 – 1000 µg / ml, preferably in a range of 1-500 µg / ml, more preferably in a range of 5-250 µg / ml, still even more preferably in a range of 10-100 µg / ml, even more preferably in a range of 20-50 µg / ml, such as at about 40 µg / ml; (iii) nicotinamide, in particular in a range of 0.1 – 100 mM, preferably in a range of 0.5 – 50 mM, more preferably in a range of 1-25 mM, even more preferably in a range of 2-10 mM, such as at about 5 mM; and optionally B27 supplement and N-acetylcysteine, preferably about 1.25 mM N-acetylcysteine. (d) a cell culture dish or cell culture container, which has been pre-coated with anti-CD28 antibody; (e) a container with IFN-ɣ; and / or (f) a container with an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen. EXAMPLES Example 1 – Tumor organoid establishment and culture To be able to study the antitumor immunity, inventors first generated a living biobank of lung tumor and benign tissue 3D organoids. Specifically, patient tumor and blood samples were collected in accord- ance with the Declaration of Helsinki from consented lung cancer patients with concurrent BioBank deposit. For the study, Helsinki University Hospital (HUS) IRB has been granted (HUS / 237 / 2021) with a statement from the institutional ethical board HUS / 970 / 2021. Lung tumor resections and biopsies were stored in wash medium (Ad- vanced DMEM / F12 reduced serum + 1% Glutamax + 1% Hepes buffer + 1% Pen / Strep) and delivered to the laboratory within an hour since the tissue was col- lected. Upon arrival, a small piece of the tissue was cut and quickly put into a freez- ing tube to be stored at -80 °C for future sequencing if required. The rest of the tissue was minced using surgical scalpels to 1-2 mm3fragments and further disso- ciated with digestion medium (Advanced DMEM / F12 supplemented with 1% Ul- traglutamine I, 1% Penicillin / Streptomycin, and 1.5 mg / ml Collagenase II) on a shaker at 37 °C for 2 hours for biopsies and overnight for resection samples. The digestion was stopped by one wash with 20% FBS in cold DMEM and followed by two washes with PBS. To increase the chance of successfully establish tumor organoids from most of the patients and be able to isolate tumor cells and fibroblasts inventors developed a two-step establishment culture system. First, inventors embedded half of the cells / fragments into 3D culture using Matrigel.30 minutes after embedding Matrigel solidified and special organ- oid medium (Advanced DMEM / F12 supplemented with 500 ng / ml R-spondin 1 (PeproTech), 25 ng / ml FGF-7 (PeproTech), 100 ng / ml FGF-10 (PeproTech), 100 ng / ml Noggin (PeproTech), 500 nM A83-01 (an ALK5 inhibitor, Merck), 5µM Y- 27632 (a Rho-kinase inhibitor; Selleckchem), 500 nM SB202190 (a p38MAPK in- hibitor, MedChemExpress), 1x B27 supplement, 1.25 mM N-acetylcysteine, 5 mM Nicotinamide, 1% Ultraglutamine I, Hepes buffer 10 mM, 1% Penicillin / Streptomy- cin, and 50 µg / ml Primocin (a broad-spectrum antibiotic formulation) was added. Second, the other half of cells / fragments were established as 2D cul- tures by resuspension with standard medium (Advanced DMEM / F12 supple- mented 1% Ultraglutamine (Lonza), 1% Penicillin / Streptomycin, 20 ng / ml FGF- basic (R & D systems), 50 ng / ml EGF (Invitrogen), 5µM Y-27632 (a Rho-kinase in- hibitor; Selleckchem)) then plated in two wells of tissue treated 6-well plate. After two-to-six days and based on cells status following the 2D culture initiation, every well was resuspended, and suspension was transferred to the adjacent well while the original wells were supplemented with more media. This step was repeated after two days with the new well ending up with six or more wells per sample. This allows for enrichment of epithelial tumor cells or fibroblasts in different wells. Fi- broblasts are then collected and expanded in standard medium (composition as described above). Meanwhile, confluent epithelial cells at passage zero to two were col- lected and embedded in Matrigel allowing organoids formation, or directly mixed with the 3D cells. Organoid growth was assessed by Nikon Eclipse TS100 micro- scope. Based on their growth, organoids were passaged once every 0.5-2 weeks at a 1:2 split ratio. Organoids obtained from the 2D culture step and the 3D culture step were dissociated with pre-warmed TrypLE express for 5-10 minutes at 37 °C. To stop TrypLE express effect, cold 20% FBS in DMEM / F12 was added then samples were centrifuged (300 x g for 5 minutes at 4 °C), this was followed by a wash with cold advanced DMEM / F12. At this step, organoids were broken to sin- gle cells or an aggregate of 2-5 or 3-5 cells which were resuspended with Matrigel and domed then solidified at 37 °C for 30 minutes then overlaid with special organ- oids medium (composition as described above). Using the two-step organoid establishment system of the present dis- closure, inventors successfully established 3D tumor tissue organoids from 85 % (23 / 27) of patient tumor samples and 92 % (26 / 28) of benign tissue samples. Matching fibroblast cell lines were also established from 48 % (13 / 27) of the sam- ples. The following table shows patient characteristics including mutation profiling, mutant allele frequencies and PDL-1 expression of the samples. Patient Sex Age Smoking Tumor Mutation Allele PD-L1 frequency expres- (%) sion (%) ORG-2 59 M C Adeno- KRAS 74 15 carci- (Gly12Cys) 69 noma KEAP1 28 ALK ORG- 72 F N Adeno- EGFR 21 0 18T carci- noma ORG-29 66 F E Adeno- EGFR 55 <5 carci- noma ORG-35 69 F N Adeno- N / A N / A N / A carci- noma ORG-36 81 M E Adeno- KRAS 19 0 carci- (Gln61His) 26 noma ORG-39 66 M E Adeno- N / A N / A 0 carci- noma ORG-43 79 M E Adeno- EGFR 22 0 carci- noma ORG-64 61 M E Epider- N / A N / A N / A moid car- cinoma ORG-65 52 M C Epider- N / A N / A N / A moid car- cinoma ORG-54 79 F E Adeno- N / A N / A N / A carci- noma me- tastasis ORG-55 64 F E Adeno- KRAS 59 100 in the carci- (Gly12Cys) surgical noma sample, 5 in biopsy Lung-4 77 M E Adeno- KRAS N / A 0 carci- (Gly12Asp) noma Lung-19 60 F C Adeno- KRAS 17 0 carci- (Gly12Ala) 28 noma STK11 Lung-24 59 F C Adeno- N / A N / A N / A carci- noma me- tastasized from col- orectal cancer Lung-25 74 F N / A Adeno- KRAS 10 2 carci- (Gly12Val) noma Lung-35 65 M N / A Adeno- EGFR 48 0 carci- noma F, female; M, male; C, current smoker; E, ex-smoker; N, never-smoker; and N / A, not-applicable. Example 2 – Generation of autologous reactive immune cells To study the systemic immune effects and achieve tumor-specific im- mune responses, we isolated circulating peripheral blood mononuclear cells (PBMCs) from the patient blood and mimicked the systemic antitumor activation by co-culturing the cells with autologous MHC-I proficient tumor organoids (see also Figure 1). As noted in Example 1, patient tumor and blood samples were collected in accordance with the Declaration of Helsinki from consented lung cancer patients with concurrent BioBank deposit Peripheral blood was collected into lithium hep- arin vacuum tubes according to Helsinki University Hospital Laboratory’s (HUSLAB) standard protocols in a laboratory chosen by the patient. Peripheral blood mononuclear cells (PBMCs) were isolated from pe- ripheral blood by SepMate density gradient centrifugation. Ficoll-Paque (density gradient medium at room temperature) was pipetted to the 50 ml SepMate tube through the central hole insert according to the manufacturer’s instructions. The peripheral whole blood was diluted with an equal volume of PBS + 2% fetal bovine serum (FBS), then gently pipetted down the side of the tube above the insert. The samples were then centrifuged at 1200 x g for 10 minutes at room temperature with breaks on. PBMCs and plasma were poured off into a separate 50-ml tube and washed 2x with PBS + 2% FBS. PBMCs are resuspended with RPMI-1640 supple- mented with 2mM L-Glutamine, 100 U / ml penicillin, 100 ug / ml streptomycin, and 10% FBS (complete RPMI media) then assessed for viability and cultured or cryo- preserved. Alternatively, PBMCs were isolated by LeucoSep (Greiner bio-one) den- sity gradient centrifugation. Ficoll-Paque (density gradient medium at room tem- perature) was pipetted to the 50 ml LeucoSep tube and then centrifuged at 1000 x g for 30 seconds according to the manufacturer’s instructions. The peripheral whole blood was diluted with an equal volume of PBS then pipetted to the Leu- coSep tube. The samples were then centrifuged at 800 x g for 25 minutes at room temperature with breaks off. The most upper layer plasma was discarded and remaining plasma with PBMCs layer was collected to a new 50 ml Falcon tube using a disposable transfer pipet. To wash the plasma, PBS was added and samples were centrifuged at 160 x g for 10 minutes at room temperature with breaks off. The samples were then washed with PBS and centrifuged at 250 x g for 10 minutes. Isolated PBMCs were resuspended to a freezing medium containing 7- 10% DMSO, and 90-93% FBS at a concentration of 5-10 x 106cells / mL and placed in Cryo freezing container at -80 °C for 24 hr to allow even cooling. The following day, samples were moved to – 150 °C for long-term storage. PBMCs were carefully thawed in a 37 °C water bath for 30 sec with gentle swirling. Thawed samples were then washed 2x with RPMI 1640 supplemented with 1% Penicillin / Streptomycin, and 10% FBS (500 x g for 5 minutes at room temperature). Once thawed, PBMCs are cultured with RPMI 1640 (supplemented with 2mM L-Glutamine, 1% Penicil- lin / Streptomycin, and 10% FBS) medium overnight for recovery. For the generation of reactive immune cells, inventors followed a pro- tocol that was established by Cattaneo et al., 2020 (incorporated herein by refer- ence), but using tumor organoids prepared as described in Example 1. Two days before co-culture, tumor organoids (1-5 x 104for every 2 x 106PBMC) were isolated from Matrigel by mechanical dissociation followed by 15 minutes incubation with pre-heated dispase (2 mg / ml in PBS) at 37 °C. The dispase was deactivated by 0.5 M EDTA (100 µl for each 1 ml of dispase) and washed with PBS at 300 x g for 5 minutes at room temperature then resuspended special organ- oid medium [described above] and plated in tissue culture-treated 6-well plate. Or- ganoids were cultured for 24h at 37 °C. One day before co-culture, organoids were stimulated overnight with 200 ng / ml IFNγ to enhance their antigen presentation. 96-well U-bottom plate was coated with 5 µg / ml anti-CD28 antibodies (to provide co-stimulatory signals, mouse anti-human CD28 (eBioscience)) in PBS (50 µl per well). The plate was wrapped with parafilm and incubated for 24h at 4 °C. Cryopreserved PBMCs were thawed in 15 mL T-cell thawing medium (RPMI 1640 supplemented with 1% Ultraglutamine I / (Lonza), 1% Penicillin / Streptomycin, and 10% FBS) and centrifuged at 200 x g for 10 minutes at room temperature with intermediate deceleration. PBMCs are then incubated for 15 minutes at 37 °C in 5 ml T-cell thawing medium with 1:1,000 benzonase then wash with T-cell thawing medium and pellet the cells at 200 x g for 12 minutes at room temperature. Cells were resuspended at 2 x 106per mL in T-cell culture me- dium (RPMI 1640 supplemented with 1% Ultraglutamine I (Lonza), 1% Penicil- lin / Streptomycin, and 10% human male serum (Merck)) with 150 U / mL IL-2 (Pre- proTech) and incubated overnight in a 15 mL falcon tube at 37 °C. The next day, stimulated organoids with IFNγ were collected and pel- leted at 300 x g for 5 minutes at room temperature. The pellet was resuspended with 1 mL TrypLE Express and combined with the remaining cells that adhered to the bottom of the 6-well plate for 5 minutes at 37 °C then washed with PBS and cells were centrifuged at 300 x g for 5 minutes at room temperature. Dissociated organoids were then resuspended at 5 x 104cells per mL of T-cell culture medium (composition as described above). Overnight incubated PBMCs were washed with PBS and resuspended at 1 x 106cells per mL in T-cell culture medium and supple- mented with 300 U / mL IL-2 (PreproTech) and 40 µg / mL anti-PD1 (Nivolumab, Selleckchem). Equal volumes of dissociated organoids and PBMCs were mixed with PBMCs:organoids ratio of 20:1. Anti-CD28 coated 96-well plate was washed 2x with PBS. Tumor cells and PBMCs were co-cultured by plating 200 µl of the disso- ciated organoid-PBMCs suspension per well. Co-culture medium was refreshed three times a week including 300 U / mL IL-2 and 40 µg / mL anti-PD1. Seven days post co-culture, PBMCs were collected and counted then re- stimulated for another seven days with freshly isolated organoids (which been stimulated with IFNγ 24h prior to co-culture) by seeding 2 x 105PBMCs with 104dissociated organoids per well of anti-CD28 pre-coated plate. By the end of co-culture reactive immune cells were collected and cryo- preserved or used for downstream analysis and tumor killing assay. Reactive im- mune cells were cryopreserved at 5 x 106cell / ml in cold 10% DMSO in human male serum then placed in freezing container at – 80 °C. To investigate potential changes in T cell sub-populations resulting from the co-culture, flow cytometry-based immunoprofiling was used to measure the percentage of helper (CD3+ / CD4+) and cytotoxic cells (CD3+ / CD8+) T cells in the baseline PBMCs versus in the T cells isolated from the two-week co-culture. In the population level, the two-week co-cultures of PBMCs with matching organoids did not result in a significant shift in the original proportions of CD3+ cells or CD4+, CD8+ cells (Figure 2). However, CD4+T cell populations were slightly decreased in 4 samples (ORG-29, ORG-36, ORG-43, and ORG-55). Meanwhile, CD8+T cell popu- lations were enriched in 5 samples (ORG-36, ORG-43, ORG-55, LUNG-4, and LUNG- 35 T). To further assess changes in the T cell activation status after stimula- tion, we measured the IFNγ expression in the cytotoxic T cells by flow cytometry (Figure 3A and 3B). Briefly, 105immune cells isolated from the 14 days co-culture were res- timulated with 5 x 104tumor cells at a 2:1 effector: ratio. Tumor cells and immune cells, including T cells, were co-cultured in coated anti-CD2896-well plates in T- cell culture medium supplemented with 20 ug / mL anti-PD1 antibody (1:150) (Nivolumab, Selleckchem). For the positive control, 105PBMCs were seeded with ImmunoCult (25:1000) (CD3 / CD28 / CD2 T cell activator (StemCell)). Both condi- tions were co-cultured for 1 hr at 37 ° then Golgi-Stop (1:1500) (BD) and Golgi-Plug (1:1000) (BD) and were added and co-culture continued for another 4 hr at 37 °C to inhibit surface proteins transfer to increase their detection by antibodies. Cells were pelleted at 330 x g for 5 minutes at 4°C and washed twice with FACS buffer (PBS supplemented with 1% EDTA (0.5 M) and 5 mg BSA). After the washes, cell-surface staining was performed by adding 1:20 Mouse anti-CD4– FITC (Stemcell technologies), 1:20 Mouse anti-CD3–PerCP–Cy5.5 (BD), 1:200 anti- CD8–V450 (BD) antibodies and 1:1,000 near-infrared viability dye in FACS buffer for 30 minutes. Cells were washed with FACS buffer twice then fixed by adding 100 µl of Fixation / Permeabilization solution (BD Biosciences) and permeabilized for 20 minutes on ice then washed twice with 1x Perm / Wash buffer (containing FBS and Saponin) in distilled H2O (BD Biosciences) and intracellularly stained with 1:40 Mouse γ -APC (BD) in Perm / Wash buffer for 30 minutes at 37 °C. Cells were then twice washed with Perm / Wash buffer and resuspended in FACS buffer and rec- orded by BD FACSVERSETM. IFNγ production was induced in 60 % (9 / 15) of the samples, where 47 % (7 / 15) of the samples didn’t have any baseline IFNγ expression and 13 % (2 / 15) patients had pre-existing production of IFNγ which was further increased by the co-culture (LUNG-4, ORG-43) (Figure 3B). IFNγ production by CD8+ T cells was observed to be patient and time-point-dependent (Figure 4). Finally, inventors wanted to investigate if the established reactive im- mune cells, including T cells, were specifically activated towards the matching tu- mor sample. To study this, baseline PBMCs versus reactive immune cells were co- cultured with matching tumor organoids for 48 hours, after which cell death was evaluated. Briefly, tumor organoids were isolated using 5 U / ml Dispase for 10-15 minutes followed by EDTA deactivation and washes. Organoids were then resus- pended with 2 ml special organoid medium [described above] / well and plated in a 6-well plate then incubated at +37 °C, 5% CO2. After 24 h, organoids were collected, and an aliquot of the suspension was isolated and then treated with TrypLE to dis- associate organoids into single cells aiming to determine tumor single cell count within the original organoids suspension. Tumor organoids were plated at 1 x 104cells / well in 100 µl special media on a 96-well plate flat bottom (Corning) without or with stimulated immune cells, including T-cells, in T cell media (1:4 target to effector ratio), without or with 200 µg / ml anti-PD1 (Nivolumab) and with or with- out 200 µg / ml anti-PD1 (Nivolumab) combined with chemotherapy (450 µM / ml Carboplatin + 2.5 µM / ml Pemetrexed). For conditions with tumor organoids only, 100 µl of T cell media was added to reach 200 µl final volume. For conditions with stimulated T cells, 10 ng / ml IL-2 was added. Co-cultures were then incubated at 37 °C, 5% CO2 for 48 h. This was followed by performing Caspase 3 / 7 Glo assay (Promega). Luminescence was measured using Spark multimode microplate reader. Alternatively, CellTox green (Promega) assay was performed, and fluores- cence was measured by the live imager Cellcyte at 48 time points. In a 2D killing validation assay the reactive immune cells, including re- active T cells, resulted in significantly higher tumor killing in comparison to base- line PBMCs, indicating that tumor-specific activation had occurred during the co- culture (Figure 5). Single cell sequencing (scSeq) was used to more broadly evaluate the activation status of the autologous immune cells when cultured together with the tumor cells, as well as to understand the individual patient’s tumor and immune cell responses in co-culture with or without the presence of immune cells and im- munomodulatory drugs. Inventors found that the co-culture induced a broad acti- vation of the immune cells, including different T cell subtypes and of NK cells, but there were differences in the level of activation in each of the tested patient. Tumor organoids were isolated using 5 U / ml Dispase for 10-15 minutes followed by EDTA deactivation and washes. Organoids were then resuspended with 2 ml special media / well and plated in a 6-well plate then incubated at 37 °C, 5% CO2. After 48 h, organoids were collected, and an aliquot of the suspension was isolated and then treated with TryplE to disassociate organoids into single cells aiming to determine tumor single cell count within the original organoids suspen- sion. Tumor organoids were plated at 50,000 cells / well in 200 ul special media on a 48-well plate without or with stimulated immune cells, including T-cells, in T cell media (1:4 target to effector ratio) and without or with 200 ug / ml Nivolumab. For conditions with tumor organoids only, 200 ul of T cell media was added to reach 400 ul final volume. For conditions with stimulated immune cells, including T cells, 10 ng / ml IL-2 was added. Co-cultures were then incubated at 37 °C, 5% CO2 for 48 h. The co-culture was performed in duplicates for each condition. Experiments were done with tumor organoids, stimulated immune cells, including T cells, and PBMCs of three patients. After 48 h of co-culture, cells from each well were disso- ciated into single cells using TrypLE followed by 2-3 washes in 10 ml PBS. Depend- ing on cell’s viability, cells were resuspended with 100 ul cold washing buffer 1 or washing buffer 2, 10 ul TruStain FcX blocking reagent (Biolegend) was added and cells were blocked for 10 minutes at +4 °C. A unique TotalSeq-C hashing antibody (Biolegend) was added to each sample (2ul / 2ug per sample) and cells were incubated for 30 minutes at +4 °C. Cells were then washed 3-5 times with 3.5ml washing buffer 1 or washing buffer 2 then samples were combined in cold PBS + 0.04 % bovine serum albumin (BSA) and proceeded to scRNA-seq. Single cell gene expression profiles were studied using 10x Genomics Chromium Single Cell 5' Gene expression with Feature Barcoding technology platform. The Chromium Single Cell 5’RNAseq run and library preparation were done using the Chromium Next GEM Single Cell 5' Immune Profiling with Feature Barcoding technology version 2 chem- istry. The Sample libraries were sequenced on Illumina NovaSeq 6000 system us- ing read lengths: 26bp (Read 1), 10bp (i7 Index), 10bp (i5 Index) and 90bp (Read 2). As illustrated in Figure 13, the personalized character of the method of providing autologous tumor organoid-activated immune cells could be demon- strated that by applying the method for different patients have multiple shared as well as individual genes upregulated in the CD4+ (helper) and CD8+ (cytotoxic) T cells after the PBMC / tumor co-culture protocol. Example 3 – Use of the Solid-IO platform for studying responses to anti-PD-1 and chemotherapy treatments ex vivo To study the systemic cytotoxic effects of immune cells with or without stimulation with IO drugs, we combined the tumor organoids prepared as de- scribed in Example 1, tumor reactive immune cells prepared as described in Exam- ple 2, and the tumor microenvironment components on a high-throughput micro- fluidic organ-on-a-chip (Solid-IO platform). To mimic the tumor site, organoids were loaded into the middle channel of the microfluidic chip in a 3D extracellular matrix. In order to model immune cell, including T cell, infiltration into the tumor site from the blood vessel, the previously attained patient-matched reactive im- mune cells were added to the proximal side channel of the microfluidic chip. To study the drug efficacy and perfusion into the tumor site, standard-of-care or im- munotherapy drugs were added into the distal side channel of the chip (Figure 6). Specifically, the AIM idenTX 3 Chip (AIMbiotech) and Mimetas Organo- Plate 3-lane 40 / 64 (Mimetas) microfluidic devices were used as a basis. Tumor organoids were mechanically isolated from Matrigel then were disassociated to single cells or aggregate of 2-5 cells by 10-15 minutes incubation at 37 °C with Try- plE. Disassociated tumor cells were resuspended with 90% cold Matrigel and seeded at 1 x 103cells / µl for the AIM devices or 10 x 103cells / µl in the Mimetas devices.10 µl and 2 µl of tumor cells Matrigel suspensions were loaded to the mid- dle channels of AIM and Mimetas, respectively. Matrigel was allowed to solidify for 15-30 minutes at 37 °C. In both devices, 50 µl of special organoid media (composi- tion described above) was added to the right and left top-bottom media channels. In the AIM chip, an extra 50 µl special organoid media was added to each of the four media inlets. Tumor cells in Matrigel within the microfluidics were then allowed to form organoids for 48h at 37 °C. To set up the Solid-IO co-cultures and screen for immunotherapy re- sponses, special organoid media was aspirated from the media inlets at day 2 and 50 µl of T cell culture media (composition described above) with or without 2 x 105or 1 x 105activated immune cells were seeded to the inlet of the right-top media and another 50 µl of T cell culture media to the left-bottom channel in AIM and Mimetas devices, respectively. This was followed by adding 50 µl of special organoid media with or without selected drugs to the inlets of the right top and bottom media channels. In the AIM chip, an extra 50 µl special media was added to each of the four media inlets. When all components were loaded to the microfluidics, the devices were placed for 48 h in a 37 °C incubator on a rocker with a speed of 1 rpm to create a flow. The used drugs are 100 nM / ml Osimertinib, 250 nM / ml Sotorasib, 100 µg / ml Nivolumab, 30 µg / ml Relatimab, chemotherapy as combination of 450 µM / ml Carboplatin + 2.5 µM / ml Pemetrexed. Live / Dead fluorescence staining was performed by loading 1:5 Nex- celom ViaStain™ AO / PI Staining Solution diluted in PBS. The cells were incubated with the dye for 10 minutes in the dark then washed three times with PBS. Cells were then fixed by adding 2% PFA for 10 minutes followed by washing with PBS. Each condition was imaged by the Nikon Eclipse Ti-E microscope. Images were quantified by ImageJ software. Before quantification, all data were blinded to avoid bias. The detailed developed quantification steps are as following: I- open images and split color channels (Live-green and Dead-red) and each channel is treated separately, II- from edit choose option the conversion and select a- scale when converting, b- weighted RGB conversion, III- from analysis choose set measurement then select area, limit to threshold, and decimal places to 3, IV- convert each channel to 8-bit by selecting image, type, then 8-bit which will convert channels to gray, V- measuring mask was generated independently to fit the gen channel area, open the mask and place it on the area to be measured, VI- from image chose adjust then threshold then select “Over / Under” and set, then chose lower threshold to be 30 and upper threshold to be 255, each channel will be converted to blue and organoids / cells will remain gray, VII- to measure the cover- age area of organoids / cell in the live and dead channel press analyze then measure each channel. Values obtained from each channel were summed up to get the total value. To get the live and dead ratio, inventors used value from the green channel / total value x 100 = % of live organoids and value from the red channel / total value x 100 = % of dead organoids. We first used Solid-IO to screen for responses to anti-PD-1 (Nivolumab) or its combination with chemotherapy (carboplatin / pemetrexed) in eight NSCLC patients harboring different clinically relevant mutations. All except one of the pa- tients (ORG-2) had very low clinical baseline PD-L-1 expression (<5 %) (Figure 7), which could be indicative for a poor clinical response to anti-PD-1. In the vehicle control treated group, the addition of tumor reactive T cells was inducing signifi- cant killing of the tumor tissue in Solid-IO (Figure 8). As the clinical PD-L-1 expres- sion data suggested, PD-1 blockage by Nivolumab did not enhance T cell killing of tumor organoids. This was true also in the case of ORG-2 with 15 % PD-L-1 express- ing cells. On the level of the population average, the combination of Nivolumab with chemotherapy and stimulated immune cells had no significant difference when compared to the condition with the same condition without the immune cells (Figure 8). However, we were able to detect individual responders to the combina- tion Nivolumab and chemotherapy when combined with reactive immune cells in 43 % (3 / 8) of the patients (ORG-2, ORG-55, and LUNG-19; with 20%, 10%, and 11% higher tumor killing, respectively) (Figure 8, Figure 9). Interestingly, all of the combination responder patients were harboring different mutations in KRAS driver oncogene, which is a known inducer for high tumor mutational burden and thus correlated with higher antitumor immunity. Surprisingly, however, one of the combination responders (LUNG-19) was also mutated for STK11 (28 % allelic fre- quency), which is typically connected with poor anti-PD-1 response. Since the al- lelic frequency for the STK11 mutation was relatively low, it is possible that the responding tumor cells were originating from the non-mutated population, how- ever, this was not tested in our study. As a summary, our results suggest that Solid-IO platform could provide a valuable tool for teasing out personalized IO drug responses in patients. Some NSCLC patients could benefit from the combination of Nivolumab and chemother- apy despite having low PD-L1 expression. Example 4 - Advanced Solid-IO with artificial vasculature In the advanced Solid-IO setting, endothelial tubule and patient- matching fibroblasts obtained as described in Example 1 were added to the system to better mimic the patient vasculature and immune suppressive microenviron- ment (Figure 10). The advanced Solid-IO was established using 3-lane Mimetas Organo- Plate and had different components (Figure 10, Figure 12). Tumor organoids were mechanically isolated from Matrigel then were disassociated to single cells or aggregate of 2-5 cells by 10-15 minutes incubation at 37 °C with TryplE. Matching cancer-associated fibroblasts (CAFs) were isolated from 2D culture by 5 minutes incubation at 37 °C with Trypsin. A suspension of 10 x 103tumor cells / µl + 2.5 x 103CAFs / µl in cold Matrigel was prepared then 2 µl of the cold tumor-fibroblast Matrigel mix was loaded to the middle channel inlet. Matrigel was allowed to solidify for 15 minutes at 37 °C. After solidification, Human umbilical vein endothelial cells (HUVEC) were isolated from 2D cultures using Trypsin, and 2 µl of 7.5 x 103 / µl HUVECs cells in endothelial media were injected into the right-top media inlet followed by add- ing 50 µl endothelial media to the inlet. The Mimetas plate was then placed on its side in the customized holder in a 75° angle in the incubator to allow the HUVECs cells in the channel to settle and attach to the ECM Matrigel for four hours. After HUVECs cells are attached to the ECM gel, 50 µl of endothelial me- dia are added to the bottom-right media inlet and 50 µl of special organoid media are added to each of the left media-channel inlets. The Mimetas plate was then placed in the incubator on a rocker at 1 rpm pm to generate flow. The cells are cultured in the chip for four days allowing for organoids and endothelial tubule formation. Immune cells and drugs are then added to the Solid-IO as described in Example 3. Endothelial tubule was successfully established in the Solid-IO (Figure 10). Matching fibroblasts were also successfully cultured in the Solid-IO. To assess whether the tubule prevent drugs diffusion to the tumor site, we compared control (organoids + endothelial tubule) to condition with chemo- therapy. Chemotherapy has resulted in a higher tumor killing while HUVECs cells remained viable (99%) after 6 days of culture (Figure 11). Example 5 – Use of the Solid-IO platform for cytokine profiling Cytokines are signaling proteins that play a critical role in shaping im- mune responses against tumor cells in the tumor microenvironment (TME). To in- vestigate differences in cytokine secretion between baseline PBMCs and tumor re- active immune cells, with or without the presence of IO drugs, inventors collected culture medium after 48 hours of co-culture from the Solid-IO platform and ana- lysed the secreted cytokines using Luminex cytokine profiling. The profiling was performed using Bio-Plex Pro Human Immunotherapy Panel with Luminex 200 in- strumentation. It was found that reactive immune cells had induced secretion of all im- mune-related cytokines compared to the baseline PBMCs, indicating that tumor stimulation enhances overall immune activity and cytokine secretion in the TME. Next, inventors profiled the cytokines collected from Solid-IO from a re- sponder patient (LUNG-24) and from a non-responder patient (LUNG-25). Inter- estingly, in the responder patient inventors detected higher levels in of IFNγ-in- duced chemokines IP-10, MIP-1a and MIP-1b, which are known promoters of T cell recruitment and activation. In contrast, the non-responder patient had higher lev- els of a STAT6-activated cytokine, which has shown to have immunosuppressive effects and can inhibit the activity of T cells and dendritic cells. Thus, this provides a potential mechanism for poor antitumor activity in this patient. In conclusion, differential patient responses to the combination of IOs were associated with differences in cytokine profiles. The responder patient showed higher level of IFNγ-induced chemokines involved in T cell recruitment and activation, whereas the non-responder patient exhibited higher levels of a specific immunosuppressive cytokine. By targeting the differential cytokine profiles observed in responders and non-responders, the development of biomarkers based on cytokine profiles extracted from the Solid-IO platform could lead to more personalized and effective immunotherapy approaches. It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The inven- tion and its embodiments are not limited to the examples described above but may vary within the scope of the claims. REFERENCES 1- Al-Samadi, A., Poor, B., Tuomainen, K., Liu, V., Hyytiäinen, A., Suleymanova, I., ... & Salo, T. (2019). In vitro humanized 3D microfluidic chip for testing personalized immunotherapeutics for head and neck cancer patients. Experi- mental Cell Research, 383(2), 111508. 2- Aung, A., Kumar, V., Theprungsirikul, J., Davey, S. K., & Varghese, S. (2020). An engineered tumor-on-a-chip device with breast cancer–immune cell interac- tions for assessing T-cell recruitment. Cancer research, 80(2), 263-275. 3- Ayuso, J. M., Rehman, S., Virumbrales-Munoz, M., McMinn, P. H., Geiger, P., Fitzgerald, C., ... & Beebe, D. J. (2021). Microfluidic tumor-on-a-chip model to evaluate the role of tumor environmental stress on NK cell exhaustion. Sci- ence Advances, 7(8), eabc2331. 4- Ayuso, J. M., Truttschel, R., Gong, M. M., Humayun, M., Virumbrales-Munoz, M., Vitek, R., ... & Skala, M. C. (2019). Evaluating natural killer cell cytotoxicity against solid tumors using a microfluidic model. Oncoimmunology, 8(3), 1553477. 5- Cattaneo, C. M., Dijkstra, K. K., Fanchi, L. F., Kelderman, S., Kaing, S., van Rooij, N., ... & Voest, E. E. (2020). Tumor organoid–T-cell coculture systems. Nature protocols, 15(1), 15-39. 6- de Haan, L., Suijker, J., van Roey, R., Berges, N., Petrova, E., Queiroz, K., ... & van den Broek, L. J. (2021). A microfluidic 3D endothelium-on-a-chip model to study transendothelial migration of T cells in health and disease. Interna- tional Journal of Molecular Sciences, 22(15), 8234. 7- Nguyen, M., De Ninno, A., Mencattini, A., Mermet-Meillon, F., Fornabaio, G., Evans, S. S., ... & Parrini, M. C. (2018). Dissecting effects of anti-cancer drugs and cancer-associated fibroblasts by on-chip reconstitution of immunocom- petent tumor microenvironments. Cell reports, 25(13), 3884-3893. 8- Rosenberg, S. A., & Restifo, N. P. (2015). Adoptive cell transfer as personalized immunotherapy for human cancer. Science, 348(6230), 62-68. 9- Simoni, Y., Becht, E., Fehlings, M., Loh, C. Y., Koo, S. L., Teng, K. W. W., ... & New- ell, E. W. (2018). Bystander CD8+ T cells are abundant and phenotypically distinct in human tumour infiltrates. Nature, 557(7706), 575-579. - Schuth, S., Le Blanc, S., Krieger, T.G. et al. Patient-specific modeling of stroma- mediated chemoresistance of pancreatic cancer using a three-dimensional organoid-fibroblast co-culture system. J Exp Clin Cancer Res 41, 312 (2022).- Maulana et al. Immunocompetent cancer-on-chip models to assess immuno- oncology therapy,Advanced Drug Delivery Reviews, 173: 281-305 (2021).- Gopal, S., Kwon, SJ., Ku, B. et al. 3D tumor spheroid microarray for high- throughput, high-content natural killer cell-mediated cytotoxicity. Commun Biol 4, 893 (2021). - Saraiva et al. Establishment of a 3D Co-culture With MDA-MB-231 Breast Can- cer Cell Line and Patient-Derived Immune Cells for Application in the Devel- opment of Immunotherapies Front. Oncol., Sec. Cancer Immunity and Immu- notherapy Volume 10 (2020). - US Patent No.10,472,599

Claims

CLAIMS 1. An in vitro method of establishing tumor organoids from a cancer tissue sample obtained from a subject, the method comprising the steps of (a) dissociating the cancer tissue sample into cells and fragments; (b) propagating a first portion of the cells and / or fragments obtained in step (a) in a first 3D-culturing step; (c) propagating a second portion of the cells and / or fragments obtained in step (a) in a 2D-culturing step such as to enrich epithelial tumor cells and optionally fibroblasts; (d) combining the propagated cells and fragments obtained in step (b) with the propagated cells and fragments obtained in step (c), and propagating the combined cells and fragments in a second 3D-cul- turing step; thereby establishing tumor organoids from the cancer tissue sample.

2. The method of claim 1, wherein the cancer tissue sample is a cancer tissue sample from a malig- nant cancer tumor, in particular wherein the cancer is selected from the group consisting of lung, colon, rectal, prostate, breast, urinary bladder, thyroid, kidney, renal, epithelial, or ovarian cancer; and / or wherein the cancer tissue sample is a cancer tissue sample from an ade- nocarcinoma, epidermoid carcinoma, and / or colorectal cancer.

3. The method of any preceding claim, wherein the cancer tissue sample is a cancer tissue sample from a cancer comprising at least one mutation in a gene associated with tumor resistance, in particular wherein the at least one mutation is a mutation in a gene selected from the group of genes consisting of KRAS, EGFR, KEAP1, ALK, STK11, MET, TP53, ROS1, RB1, NOTCH1, NOTCH2, BRAF, NTRFK1 / 2 / 3, RET, ERBB2, HRAS, NRAS, ASCL1, NF1, PI3CA, FGFR1 / 2, MAP2K1, in particular from the group of genes consisting of KRAS, EGFR, KEAP1, ALK, and STK11.

4. The method of any preceding claim, wherein step (b) comprises propagation in a culture medium comprising at least two or more, preferably all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R- spondin and / or WNT, preferably R-spondin 1; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190; (vii) nicotinamide; and optionally B27 supplement and N-acetylcysteine; and / or wherein step (c) comprises propagation in a culture medium comprising at least two or more, preferably all, of the following (i) FGF, preferably FGF-basic; (ii) EGF; (iii) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632.

5. The method of any preceding claim, wherein step (c) further comprises collecting and propagating cancer-associated fibroblasts, preferably in the same culture medium than the culture medium used in step (c).

6. The method of any preceding claim, wherein step (d) is carried out in an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen, and / or wherein step (d) comprises propagation in a culture medium comprising at least two or more, preferably all, of the following(i) an inducer of the WNT / β catenin signalling pathway, such as R- spondin and / or WNT, preferably R-spondin 1; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF-7 and FGF-10; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase inhibitor is Y-27632; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK inhibitor is SB202190; (vii) nicotinamide; and optionally B27 supplement and N-acetylcysteine.

7. An in vitro method of providing autologous tumor organoid-activated im- mune cells, wherein the method comprises (a) establishing tumor organoids from a cancer tissue sample obtained from a subject according to the method of any one of claims 1-6; and (b) co-culturing the tumor organoids with immune cells obtained from said subject; thereby providing autologous tumor organoid-activated immune cells.

8. The method of any one of claims 7, wherein the immune cells are im- mune cells isolated from whole blood, peripheral blood mononuclear cells (PBMCs), spleen, lymph nodes, buffy coats, pleural fluid, bone marrow aspirates, tumor, and / or derived from induced pluripotent stem cells, preferably wherein the immune cells are peripheral immune cells, more preferably wherein the immune cells are PBMCs.

9. The method of any one of claims 7-8, wherein the tumor organoids of step (a) are stimulated prior to step (b) such as to enhance antigenpresentation, in particular by pre-cultivation in medium comprising type-II interferon, preferably IFN-ɣ.

10. The method of any one of claims 7-9, wherein step (b) comprises co-cul- turing in a culture medium, the culture medium comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2); and / or (ii) an immune checkpoint inhibitor, preferably an immune checkpoint inhibitor selected from anti PD-1 / PD-L1 antibody, and anti-CTLA4 antibody, more preferably anti PD-1 / PD-L1 antibody, in particular an anti-PD-1 / PD-L1 antibody selected from Nivolumab, Pembroli- zumab, Cemiplimab, Dostarlimab, Retifanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintilimab, Tislelizumab, Toripal- imab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezoli- zumab, Durvalumab, and Avelumab, more preferably wherein the anti-PD-1 antibody is Nivolumab; and / or (iii) a T cell activating agent binding to CD28, preferably an anti-CD28 antibody, or wherein the anti-CD28 antibody has been pre-coated to a sur- face of a cell culture vessel in which the culture medium is re- ceived.

11. A method of preparing an in vitro organ culture system for mimicking tu- mor interaction with an immune system of a subject, the method compris- ing: (i) providing a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the second compartment in particular wherein the physical boundary is selected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane-based boundary, or a net-based boundary;(ii) incorporating into the first compartment a three-dimensional tumor organoid established from a cancer tissue sample obtained from a subject, and a suitable tumor cell growth medium, and (iii) introducing into the second compartment autologous immune cells from said subject, which have been activated by co-culturing with said established tumor organoids, and a suitable immune cell growth medium; thereby providing the in vitro organ culture system.

12. The method of claim 11, wherein the tumor organoid was established from a cancer tissue sample obtained from a subject according to the method of any one of claims 1-6; and / or wherein said autologous immune cells from said subject have been acti- vated by co-culturing with said established tumor organoids according to the method of any one of claims 7-10.

13. The method of any one of claims 11-12, wherein step (ii) further comprises incorporating cancer-associated fibro- blasts (CAF) obtained from said subject; and / or wherein after step (ii) autologous or non-autologous endothelial cells are incorporated on the tumor organoids, preferably wherein the autologous endothelial cells are derived from the matching patient’s tumor, artery or veins, and preferably wherein the non-autologous endothelial cells are Human umbilical vein endothelial cells (HUVEC), Human lung microvas- cular endothelial cells (HLMVEC), Human Pulmonary Microvascular en- dothelial cells (HPMEC), Human intestinal microvascular cells (HIMEC).

14. An in vitro organ culture system for mimicking tumor interaction with an immune system of a subject, comprising: (i) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to thesecond compartment, in particular wherein the physical boundary is selected from a membrane, a mechanical barrier, a membrane- free phase guided boundary, a gel-based boundary, a basal mem- brane-based boundary, or a net-based boundary; (ii) in the first compartment, a three-dimensional tumor organoid es- tablished from a cancer tissue sample obtained from the subject, and a suitable tumor cell growth medium, and (iii) in the second compartment, autologous immune cells from the subject, which have been activated by co-culturing with said estab- lished tumor organoids, and a suitable immune cell growth me- dium.

15. A method for determining the responsiveness of a tumor to a treatment with at least one immune-oncologic drug, comprising the steps of (a) preparing an in vitro organ culture system according to the method of any one of claims 11-12 or providing an in vitro organ culture sys- tem according to claim 14; (b) adding one or more, preferably at least two, immune-oncology drugs into the second compartment; and (c) determining the responsiveness of the in vitro organ culture system to the at least two immune-oncology drugs; in particular wherein step c) comprises determining the tumor cell growth and / or determining the viability of the tumor organoid cells in the first com- partment, wherein a decreased tumor cell growth and / or a decreased via- bility is indicative for an effective response of the tumor to the treatment with said one or more immune-oncology drug.

16. The method of any one of claim 15, wherein the method is repeated with a plurality of the same in vitro organ culture system for different immune-oncology drugs or combinations of different immune-oncology drugs, thereby identifying a personalized ef- fective immune-oncology therapy for a patient; orwherein the method is repeated with a plurality of the same in vitro organ culture system for different treatment regimens of an immune-oncology drug or drug combination, thereby identifying an effective treatment regi- men; or wherein the method is repeated with a plurality of different in vitro organ culture system for the same immune-oncology drug or with the same combination of immune-oncology drugs, thereby identifying patient candi- dates who can benefit from treatment with said immune-oncology drug or said combination of immune-oncology drugs.

17. The method of any one of claims 15-16, further comprising the step of comparing tumor organoids and / or culture medium in the first compart- ment of a responsive treatment to tumor organoids and / or culture me- dium in the first compartment of a non-responsive treatment, thereby identifying a biomarker for responsive or non-responsive treatment; in particular wherein the comparison of phenotypic changes comprises a comparison of cytokine levels in culture medium between a responsive treatment and a non-responsive treatment, in particular, wherein said biomarker is indicative for (i) a personalized ef- fective or non-effective immune-oncology therapy for a patient, (ii) an ef- fective or non-effective treatment regimen, and / or (iii) a patient candidate who can or cannot benefit from treatment with said immune-oncology drug or said combination of immune-oncology drugs.

18. A kit for preparing an in vitro organ culture system mimicking tumor inter- action with an immune system of a subject, the kit comprising at least two, preferably at least three, more preferably at least four, even more preferably at least five, and most preferably all of the following: (a) a microfluidic device with a microfluidic channel with at least a first and a second compartment separated by a physical boundary, which allows a cell to move from the first compartment to the sec- ond compartment, in particular wherein the physical boundary isselected from a membrane, a mechanical barrier, a membrane-free phase guided boundary, a gel-based boundary, a basal membrane- based boundary, or a net-based boundary; (b) a tumor cell growth medium comprising at least two, preferably all, of the following (i) an inducer of the WNT / β catenin signalling pathway, such as R-spondin and / or WNT, preferably R-spondin 1; (ii) FGF, preferably FGF-7 and / or FGF-10, more preferably FGF- 7 and FGF-10; (iii) a bone morphogenetic protein (BMP) antagonist; preferably wherein the BMP antagonist is Noggin; (iv) an ALK5 inhibitor; preferably wherein the ALK5 inhibitor is A83-01; (v) a Rho kinase inhibitor; preferably wherein the Rho kinase in- hibitor is Y-27632; (vi) a p38 MAPK inhibitor; preferably wherein the p38 MAPK in- hibitor is SB202190; (c) an immune cell culture medium a culture medium, comprising (i) a T cell growth factor, preferably interleukin 2 (IL-2); (ii) an immune checkpoint inhibitor, preferably an immune check- point selected from anti PD-1 / PD-L1 antibody, and anti- CTLA4 antibody, more preferably anti PD-1 / PD-L1 antibody, in particular an anti-PD-1 / PD-L1 antibody selected from Nivolumab, Pembrolizumab, Cemiplimab, Dostarlimab, Reti- fanlimab, Vopratelimab, Spartalizumab, Camrelizumab, Sintili- mab, Tislelizumab, Toripalimab, INCMGA00012, AMP-224, AMP-514, Acrixolimab, Atezolizumab, Durvalumab, and Avelumab, more preferably wherein the anti-PD-1 antibody is Nivolumab; (iii) nicotinamide; and optionally B27 supplement and N-acetylcysteine, prefera- bly about 1.25 mM N-acetylcysteine.(d) a cell culture dish or cell culture container, which has been pre- coated with anti-CD28 antibody; (e) a container with IFN-ɣ; and / or (f) a container with an extracellular matrix gel, comprising extracellular matrix proteins, such as laminin and collagen.

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