Phosphoglycerate Mutase 1 (PGAM1) Promotes Pancreatic Ductal Adenocarcinoma (PDAC) Metastasis by Acting as a Novel Downstream Target of the PI3K/Akt/mTOR Pathway

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive tumors known, with an overall 5-year survival rate of less than 6% due to early local invasion and distant metastasis. Exploring suitable therapeutic targets associated with invasion and metastasis is required for improving the prognosis of PDAC. In this study, we investigated the role of the glycolytic enzyme phosphoglycerate mutase 1 (PGAM1) in PDAC. PGAM1 expression was examined in tissue samples of 54 PDAC patients using immunohistochemistry, and the correlation between clinicopathological expression and PGAM1 expression was determined. A survival curve was generated using the Kaplan-Meier method. After silencing PGAM1 by siRNA in pancreatic cancer cell lines Aspc-1 and Panc-1, the changes in proliferation, migration, and invasion, and signal pathways were determined. In this study, the expression of PGAM1 was found positively related to poor differentiation, metastasis, advanced clinical stage, and poor survival rate. Silencing PGAM1 decreased the proliferation of Aspc-1 and Panc-1 cells with an S phase arrest, but without influencing cell apoptosis. Migration and invasion also decreased significantly, independent of proliferation. PGAM1 was also found to promote EMT of PDAC cell lines by regulating the Wnt/beta-catenin pathway. PGAM1 itself was modulated by the PI3K/Akt/mTOR pathway as a novel downstream target and has a positive mutual regulation with HIF-1 alpha. This study indicates that PGAM1 is closely associated with clinical metastasis and poor prognosis of PDAC. PGAM1 is considered as a potential therapeutic target in PDAC metastasis.