Abstract B12: 3D perfusion bioreactor system as a model for studying cell biology of ovarian cancer

Abstract

Abstract Introduction: Epithelial ovarian cancer (EOC) is the most common cause of death among gynecologic malignancies. This is a result of challenging clinical management due to the high rate of recurrence and the development of chemoresistance in EOC patients. Therefore, the development of new therapeutics is crucial. Unfortunately, the success rate of establishing new drugs is very low. A major factor contributing to this is the lack of preclinical models that accurately predict in vivo efficacy of candidate therapeutics. Preclinical models do not accurately mimic the biomechanical regulation of the tumor microenvironment (TME) and cannot predict in vivo efficacy of candidate therapeutics. We have developed an EOC 3D perfused bioreactor system that recapitulates EOC tumor biology; better predicts the clinical response of new drug candidates, thereby eliminating ineffective candidates prior to clinical trials; and incorporates tumor biomechanical regulation. Materials and Methods: EOC cell lines (luciferase-tagged SKOV-3 and OVCAR-8) were embedded in a relevant ECM (5.25 × 105 total cells/100 uL ECM) containing 90% bovine collagen I + 10% basement membrane (Matrigel) and injected into a polydimethylsiloxane bioreactor (PDMS). The volume was then perforated by five wires and the bioreactor was placed in the incubator (37C, 5%CO2) for polymerization. After that, the wires were removed to create microchannels so that the cell culture media (RPMI 10% FBS, 1% penicillin-streptomycin-gentamicin) can flow through the perfusion bioreactor system and provide nutrient delivery and gas exchange, which helps maintain viability and function of surrounding cells. Finally, the bioreactors were connected to a peristaltic pump that allows the cell culture media to run over 14 days, along the channels and through the matrix. We monitored cell growth over 14 days using bioluminescence (BLI) and these results were validated with histologic analysis of the cell density. In order to prove that the bioreactor keeps EOC biology, by immunohistochemical (IHC) analysis with p53 and PAX8, clinically used ovarian cancer markers. Results and Discussion: For our preliminary data utilizing the 3D perfusion bioreactor system in ovarian cancer, we first used the luciferase-tagged OVCAR-8 cell line to evaluate cell growth. The bioluminescence signal showed a linear increase over 14 days. These results were validated histologically with cell density by measuring the number of nucleated cells per micron2. Graphical representation of the region of interest (ROI) showed a high correlation between manual determination of cell number and bioluminescence score. In our second experiment, we used the luciferase-tagged SKOV-3 cell line (high-grade serous origin) and we also monitored cell growth over 14 days using BLI and histologic analysis of the cell density as described for OVCAR-8 using the same conditions in the bioreactor. IHC analysis with p53 and PAX8 was positive and proved that the perfusion bioreactor system keeps EOC biology. Citation Format: Alba Martinez, Molly Buckley, Joel Berry, Rebecca Arend, Michael Birrer. 3D perfusion bioreactor system as a model for studying cell biology of ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr B12.