Silencing PFKP inhibits starvation-induced autophagy, glycolysis, and epithelial mesenchymal transition in oral squamous cell carcinoma

Abstract

The tumor starvation microenvironment plays a pivotal role in the malignant progression of cancer, which is closely related to autophagy, glycolysis, and epithelial mesenchymal transition (EMT). Nevertheless, the underlying mechanisms of the starvation-mediated malignant phenotype are still not well documented. In this study, we aimed to investigate the effect of starvation on glycolysis, autophagy, and EMT in OSCC and to further elucidate the key metabolic modulator. The results showed that starvation can induce autophagy, EMT, and enhanced glycolysis in OSCC cells. We determined that the expression of the key glycolytic enzyme phosphofructokinase-platelet (PFKP) obviously increased under starvation conditions and that PFKP knockdown inhibited starvation-mediated glycolysis, autophagy and EMT in OSCC cells. Moreover, we confirmed that PFKP knockdown inhibited OSCC xenograft growth in vivo. In addition, PFKP expression was significantly increased in OSCC patients and its upregulation was associated with the presence of tumor pathological differentiation and lymph node metastasis. Taken together, our findings demonstrate that PFKP is necessary for starvation-mediated autophagy, glycolysis, and EMT, thereby promoting the malignant progression of OSCC.

Keywords: Autophagy; Epithelial-mesenchymal transition; Glycolysis; Oral squamous cell carcinoma; PFKP; Starvation.