Abstract 4084: A DGKA-cJUN-WEE1 signaling axis provides platinum resistance in ovarian cancer

Abstract

Abstract Although platinum compounds are the first-line treatment for ovarian cancer, the majority of patients relapse and develop resistance to treatment. However, the mechanism underlying resistance is unclear. Here, we report a unique platinum resistance mechanism that is mediated by a lipid messenger, phosphatidic acid (PA), in ovarian cancer. A phospho-proteomics screen revealed that PA, which is predominantly produced by diacylglycerol kinase alpha (DGKA) in ovarian cancer, activates the transcription factor c-JUN. DGKA and PA facilitate JNK recruitment to c-JUN and nuclear localization leading to its activation upon cisplatin exposure. Through a genomic screen, we identified that activated c-JUN enhances expression of WEE1 and consequently prevents cells from aberrant cell cycle progression upon cisplatin exposure. DGKA-cJUN-WEE1 signaling was elevated in tumors derived from ovarian cancer patients who did not respond to platinum-based therapy compared to tumors from patients who responded to treatment. Our study demonstrates how lipid metabolism, kinase signaling, and gene regulatory systems are intertwined to direct cisplatin resistance in ovarian cancer. Citation Format: Jie Li, Chaoyun Pan, Austin C. Boese, Anna Umano, Sumin Kang. A DGKA-cJUN-WEE1 signaling axis provides platinum resistance in ovarian cancer [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 4084.