Rictor orchestrates β-catenin/FOXO balance by maintaining redox homeostasis during development of ovarian cancer

Abstract

Rictor/mTORC2 has been demonstrated to have important roles in cancer development and progression in a number of solid and hematologic malignancies. However, little is known about the role of Rictor/mTORC2 in ovarian cancer pathophysiology. Herein, using conditional Rictor knockout mice, we were able to demonstrate that Rictor deletion disrupted glutathione metabolism through AKT/Nrf2 signaling pathway and induced intracellular oxidative stress during the malignant transformation of Kras/Pten-mutant ovarian surface epithelial cells. Elevated reactive oxygen species and activated FOXO3a in Rictor-deleted cells strikingly shifts the functional interaction of β-catenin from TCF to FOXO3a, which strongly inhibits classical Wnt/β-catenin signaling. Our findings emphasize a pivotal role for Rictor in orchestrating crosstalk between the PI3K/AKT and Wnt/β-catenin signaling in the development of ovarian cancer. Illustration of Rictor/mTORC2 in promoting tumor onset by regulating glutathione metabolism and mediating oncogenic signaling.