Introduction: Modern evaluation of novel immuno-oncological drug combinations requires a multi-faceted approach to accurately determine immune-cell activation and tumor cell viability. Additionally, retention of the intact tumor microenvironment through preparation of 3D tumor organoids is essential for the quantification of any drug-mediated changes to the complex cell-to-cell interactions that may result in changes in tumor cell viability and the immune cell profile. Here, we use multiplex cytokine analysis in combination with high-content confocal imaging of tumor cell killing to detail the efficacy of rational drug combinations for the treatment of 3D tumor organoids produced from fresh patient tumor tissue.

Materials and Methods: All patient tumor samples were obtained with patient consent and under IRB approval. Generation of 3D tumor organoids (150µm) from fresh patient tumor tissue such as bladder, colotrectal and kidney tumors was accomplished using proprietary techniques. Tumor organoids were pooled to represent tumor heterogeneity in treatment groups including nivolumab (anti-PD1), urelumab (anti-4-1BB) and a cGAS-STING agonist singly and in differing combinations. Following incubation, culture media was collected for multiplex analysis of cytokine production, and quantitative analysis of tumor cell killing was determined with high content confocal imaging.

Results: Here we demonstrated the efficacy of the 3D-Screen technology for the evaluation of the therapeutic efficacy of different immuno-oncology drugs alone and in combinations. High content confocal imaging analysis of the 3D tumor organoid microenvironment allowed for detection of changes for tumor cell killing in response to varying treatment conditions. Additionally, altered pro-and anti-inflammatory cytokine production correlated with observations of tumor cell viability. Furthermore, we correlated tumor response to ex vivo treatments with clinical, histo-morphological and molecular characteristics of the tumors in an attempt to identify markers associated with drug responsiveness.

Conclusion: These data show that 3D-Screen methodology is an effective tool for the rapid assessment of novel immuno-oncological drug combinations using fresh patient 3D tumor organoids. Furthermore, this technology would prove useful in clinical applications for the determination of specific therapeutic regimens for individualized patient care.

Citation Format: Vijayendra Agrawal, Mibel M. Pabón, Jared C. Ehrhart, Tina Pastoor, Jenny M. Kreahling, Soner Altiok. Employing ex vivo 3D-Screen technology for the development of rational combinations of immuno-oncology drugs in tumor organoids of fresh patient tissue [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6652.