Bexarotene-induced Cell Death in Ovarian Cancer Cells Through Caspase-4–mediated pyroptosis

Purpose: Bexarotene is selectively activates retinoid X recepto, whichr is a commonly used anticancer agent for cutaneous T-cell lymphoma. In this study, we aimed to investigate the anticancer effect of bexarotene and its underlying mechanism in ovarian cancer in vitro. Methods: : The ES2 and NIH:OVACAR3 ovarian cancer cell lines were treated with 0, 5, 10, or 20 µM bexarotene. After 24 hours, cell number measurement and lactate dehydrogenase (LDH) cytotoxicity assay were performed. The effect of bexarotene on CDKN1A expression, pyroptosis, and apoptosis were evaluated. Results: : Bexarotene reduced cell proliferation in all concentrations in both cells. At concentrations above 10 µM, it increased extracellular LDH activity with cell rupture. In both cells, 10 µM bexarotene treatment increased the CDKN1A mRNA levels and reduced cell cycle related protein expression. In ES2 cells, caspase-4 and GSDME were activated, whereas caspase-3 was not, indicating that bexarotene-induced cell death might be pyroptosis. Conclusion: A clinical setting dose of bexarotene induced cell cycle arrest and cell death through caspase-4–mediated pyroptosis in ovarian cancer cell lines. Thus, bexarotene may serve as a novel therapeutic agent for ovarian cancer.