Abstract

Ovarian cancer (OC) is a leading cause of gynecological malignancy in women. Around 70% of OC patients do not respond or develop resistance to first line treatment. Little is known of how tumor microenvironmental (TME) contribute to OC disease progression and response to treatment. Cancer-associated fibroblasts (CAFs), one of the most abundant components of the TME, have been shown to both suppress and support disease progression. Hence, here we sought to systematically investigate the impact of CAFs in the cell proliferation and drug response of high-grade OC. We developed co-culture technologies and live-cell imaging assay to capture the impact of CAFs as well as CAFs conditioned media (CM) on the drug response over time. Our data suggest that CAFs modulate OC cell proliferation both in a contact-dependent and -independent manner. Among five cancer cell lines tested, one (TykNu) showed the same proliferation rate regardless of environment. Further, we evaluated the sensitivity and resistance of tumor cells to 28 drug library. Our analysis revealed seven distinct clustered patterns in cancer cell drug response, three of which represented temporal changes. We found that sensitivity to Gemcitabine was seen only in co-culture with CAFs in two of the cancer cell lines (Tyknu, OvcaR8), while Adavosertib showed the same in Tyknu cells. One cell line tested, Ovsaho, demonstrated increased general level of resistance to Cisplatin and Carboplatin in direct contact with CAFs, while in monoculture and with CAFs CM sensitivity increased. In conclusion, our time-lapse co-culture drug screening assay enabled us to measure the impact of CAFs on OC cell drug response landscapes. Effects were specific to individual cell pairs and could be seen as increased or decreased response compared to monoculture. Overall, the results indicate how complex culture systems can significantly impact drug response, and how the impact of the microenvironment needs to be considered in drug discove