PROJECT SUMMARY - Core 3: Organoid, Model Systems, and Biomarkers Core The overall purpose of the Organoids, Model Systems, and Biomarkers Core of this Dana- Farber/Harvard Cancer Center Ovarian Cancer SPORE application is to provide core services to the three projects and to the other cores. The core will be directed by Drs. Alan D’Andrea, Joyce Liu, and Neil Horowitz. A primary feature of the core is our recent advances in the generation of short-term ovarian cancer organoid cultures which closely mimic the tumor from which they are derived (Hill SJ, Decker B, Roberts EA, Horowitz NS, Muto MG, Worley MJ, Feltmate CM, Nucci MR, Swisher EM, Nguyen H, Yang C, Morizane R, Kochupurakkal B, Do KT, Konstantinopoulos PA, Liu JF, Bonventre JV, Matulonis UA, Shapiro GI, Berkowitz RS, Crum CP, D’Andrea AD. Prediction of DNA Repair Inhibitor Response in Short Term Patient-derived Ovarian Cancer Organoids. Cancer Discov. 2018 Sep 13. pii: CD-18-0474. doi: 10.1158/2159-8290.CD-18- 0474.). The core is divided into three aims pertaining to 1) the development of infrastructure from HGSC tissue collection, 2) the use of PDX models to assess drug combinations in vivo, and 3) the use of HGSC organoids to assess drug combinations in vitro. The core will provide these studies, as well as relevant DNA repair and apoptosis biomarkers to the clinical trialists in the thee projects. The core will provide 1) ovarian cancer tissue collection infrastructure for participants in the SPORE, 2) the generation and analysis of short-term ovarian cancer organoid cultures, and 3) the generation and analysis of murine PDX models of ovarian cancer.