CPT2 down-regulation promotes tumor growth and metastasis through inducing ROS/NFκB pathway in ovarian cancer

BACKGROUND: Carnitine palmitoyltransferase 2 (CPT2) is a rate-limiting enzyme involved in fatty acid β-oxidation (FAO) regulation. Recently, it has been increasingly recognized that lipid metabolism dysregulation is closely implicated in tumorigenesis. However, the involvement of CPT2 in the progression of cancer is still largely unclear, especially in ovarian cancer (OC). METHODS: In the present study, CPT2 expression and its clinical significance were determined in OC tissues and cells. The biological functions and molecular mechanisms of CPT2 in OC growth and metastasis were determined by in vitro and in vivo assays. FINDINGS: We found that CPT2 was frequently down-regulated in primary ovarian serous carcinomas, which is significantly correlated with poor survival of ovarian cancer patients. Functional experiments revealed that CPT2 inhibited OC cell growth and metastasis via suppression of G1/S cell cycle transition and epithelial to mesenchymal transition (EMT), as well as induction of cell apoptosis. Mechanistically, suppression of ROS/NFκB signaling pathway by increasing fatty acid oxidation-derived NADPH production was involved in the anti-tumorigenic functions of CPT2 in OC cells. INTERPRETATION: Altogether, our findings demonstrate that CPT2 functions as a potential tumor suppressor in OC progression. CPT2 may serve as a novel prognostic marker and therapeutic target in OC.