Polyphyllin VII induces mitochondrial apoptosis by regulating the PP2A/AKT/DRP1 signaling axis in human ovarian cancer

Ovarian cancer is a gynecological malignancy with high mortality. Adjuvant therapy such as chemoradiotherapy inevitably leads to side effects and drug resistance. In recent years, traditional Chinese medicine has been widely studied for its safety, effectiveness, and unique pharmacological effects. Polyphyllin VII is an important component of Rhizoma paridis saponins, and has cytotoxic effects on many types of cancer cells. The aim of the present study was to evaluate the anti-tumor activity of polyphyllin VII in human ovarian cancer cells. Recent studies found that polyphyllin VII induces mitochondrial pathway apoptosis by increasing mitochondrial division, but the specific mechanism was unclear. The results of this study revealed that polyphyllin VII could effectively induce mitochondrial dysfunction, including increased mitochondrial division and reactive oxygen species (ROS) production. Notably, the mitochondrial location of dynamin-related protein 1 (DRP1) plays an important role in its function. In addition, polyphyllin VII enhanced the mitochondrial localization of DRP1 which is mediated by increased protein phosphatase 2A (PP2A) activity, and decreased AKT activity. A specific PP2A inhibitor, LB100, attenuated mitochondrial division and apoptosis in cells caused by polyphyllin VII, confirming the function of the PP2A/AKT pathway in polyphyllin VII treatment. Additionally, xenotransplantation experiments have also confirmed the anti-tumor effect of polyphyllin VII in vivo. Therefore, interference of the mitochondrial translocation of DRP1 through PP2A/AKT pathway may be an attractive and effective therapeutic approach by polyphyllin VII in ovarian cancer. This may provide new strategies for polyphyllin VII in the clinical treatment of ovarian cancer.