PKM2 promotes metastasis by recruiting myeloid-derived suppressor cells and indicates poor prognosis for hepatocellular carcinoma

Abstract

Pyruvate kinase M2 (PKM2) is a member of the pyruvate kinase family. Recent work has defined the “non-metabolic” functions of PKM2. However, the role of PKM2 in HCC remains unclear. To investigate the role of PKM2 in tumor growth, invasion and the prognosis of hepatocellular carcinoma (HCC), PKM2 expression was measured in HCC cell lines and tissues using qRT-PCR, western blot, and immunofluorescence assays. In in vitro experiments, PKM2 was knocked down using a short hairpin RNA lentivirus vector, and tumor cell behavior and the downstream signaling pathways and chemokine were analyzed. For the analysis of in vivo tumor growth, intratumoral and peritumoral lymphocyte infiltration were examined in nude mice. The prognostic value of PKM2 was analyzed by immunohistochemistry in two cohorts including 721 HCC patients. Together, our data obtained from cell lines, tumorigenicity studies, and primary HCC samples illustrate an oncogenic role for PKM2 in tumors. Moreover, PKM2 may serve as a novel prognostic indicator for HCC patients after curative resection, targeted therapy aimed at PKM2 may represent an effective treatment approach for HCC.