Mechanism of PTPN18 for regulating the migration and invasion of endometrial cancer cells via the MYC/PI3K/AKT pathway

Abstract

Objective. Endometrial cancer (EC) is a prevalent gynecologic malignancy. The critical role of PTPN18 in EC has been reported, while its role in the aerobic glycolysis of EC cells remains unclear. Our current study focused on the mechanism of PTPN18 in the regulation of aerobic glycolysis in EC. Methods. PTPN18 expression levels in endometrial stromal cells (KC02-44D) and EC cells (KLE, HEC-1-A, HEC-1B, and HEC-50) were determined. Following transfection of sh-PTPN18 in HEC-1-A cells, the changes in cell migratory and invasive abilities were assessed by the Transwell assay, and the changes in glucose consumption, lactic acid secretion, and ATP levels were detected using kits. The expression levels of glycolysis-related proteins HIF-1α, PKM2, and LDHA and the activation of the MYC/PI3K/AKT pathway were detected by Western blot. Additionally, sh-PTPN18 and pcDNA3.1-MYC were transfected into HEC-1-A cells to further explore their roles in the changes in aerobic glycolysis, migration, and invasion ability of EC cells. Results. Expression of PTPN18 in EC cells was up-regulated (HEC-1-A>HEC-1B>HEC-50>KLE). PTPN18 knockdown suppressed EC cell migration and invasion. Additionally, PTPN18 knockdown reduced glucose consumption, lactate production, ATP levels, and glycolysis-related protein levels (HIF-1α, PKM2, LDHA). PTPN18 knockdown inhibited the activation of the MYC/PI3K/AKT pathway in EC cells. MYC overexpression partially annulled the inhibitory effects of PTPN18 knockdown on aerobic glycolysis, migration, and invasion of EC cells. Conclusion. Our present study provided evidence that the knockdown of PTPN18 inhibited the aerobic glycolysis, migration, and invasion of EC cells by suppressing the MYC/PI3K/AKT pathway