Abstract 6790: Breaking barriers: A high-throughput 3D drug discovery platform for ovarian cancer

Abstract Background: Ovarian Cancer (OVCA) is a formidable challenge in oncology and remains the most lethal gynecologic malignancy with many cases (~80%) diagnosed at a late stage with an equally high rate of recurrence. Yet, no established OVCA models exist that faithfully recapitulate the biological complexity of metastatic OVCA. This multidisciplinary team developed a new in vitro high-throughput model that maintains the characteristics of the patient’s tumor including resident immune cells. Key breakthroughs include long term (21 day) culture of patient-derived microtumors, a functional and perfusable microgel medium (Liquid Like Solids - LLS™), microplates with controlled “pumpless” perfusion of culture media (Darcy Plates™), and integrated in situ imaging. Methods: We designed, fabricated, and validated a new 3D culture device in the standard SBS microplate format (Darcy Plate) that integrates in situ microscopy and perfusion through a bio-conjugated microgel bed (LLS). Patient tumors were collected during debulking surgery, micronized into 1 µl microtumors, suspended in LLS, and plated into the 48-well Darcy Plate. Viability and proliferation were assessed over 21 days in situ using a standard LIVE/DEAD™ kit and EDU staining, respectively. Epithelial OVCA cells and immune cells were identified with immunofluorescence microscopy. Results: Optimal media conditions (HPLM media with 10% FBS, 1% Pen/Strep, 2. 5 mg L−1 Amphotericin B, 10 mM HEPES, 0. 5 µM A83-01 -TGF-β inhibitor-, and ITS) and perfusion flow rates (100 µl/day per well) were identified that resulted in outstanding cell viability after 21 days (~100% - no detectable cell death using LIVE/DEAD™). PAX8 nuclear expression, a marker for epithelial metastatic OVCA, was retained. EDU staining confirmed cell proliferation and CD45 staining revealed retention of viable immune cells on and within the microtumor at 21 days. Drug testing to evaluate tumor response to chemotherapeutic agents, carboplatin, and emerging targeted therapies was performed by dosing the feed-wells at different concentrations and evaluating cell death through LIVE/DEAD imaging after 5 days of treatment. Conclusions: OVCA is a challenging disease with understudied biological complexity and extensive metastatic involvement. This study demonstrates that drug screening with 3D microtumors has important clinical implications and provides a unique opportunity to evaluate drug responses and personalized treatment strategies. These patient-derived microtumors retain crosstalk between diverse cell populations and the tumor microenvironment, which increases the likelihood of identifying effective therapies and drug candidates. This system retains patient-specific tumor heterogeneity and microenvironmental complexity of OVCA, offering a promising platform for drug screening, high-throughput assays, biomarker discovery, and ultimately improving treatment outcomes. Citation Format: Erin George, Diego I. Pedro, Alfonso Pepe, Angie M. Rivera, Ryan A. Smolchek, Jack E. Famiglietti, W. Gregory Sawyer. Breaking barriers: A high-throughput 3D drug discovery platform for ovarian cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 6790.