PDK1 regulates the progression of esophageal squamous cell carcinoma through metabolic reprogramming

Esophageal squamous cell carcinoma (ESCC) is one of the deadliest human malignancies characterized by late-stage diagnosis, drug resistance, and poor prognosis. Pyruvate dehydrogenase kinase 1 (PDK1) plays an important role in regulating the metabolic reprogramming of cancer cells. However, its expression, function, and regulatory mechanisms of PDK1 in ESCC have not been reported. In this study, we found that PDK1 silence and dichloroacetic acid (DCA) significantly inhibited the growth of ESCC cells and induced cell apoptosis. Interestingly, PDK1 is a direct target of miR-6516-5p, and miR-6516-5p/PDK1 axis suppressed the growth of ESCC cell by inhibiting glycolysis. Moreover, DCA and cisplatin (cis-diammine-dichloroplatinum, DDP) synergistically inhibited the progression and glycolysis ability of ESCC cells both in vitro and in vivo by increasing oxidative stress via the inhibition of the Keap1/Nrf2 signaling pathway. And, Tert-butylhydroquinone (TBHQ), a specific activator of the Keap1/Nrf2 signaling, could diminish the synergic antitumor effects of DCA and DDP on ESCC cells. Collectively, our findings indicate that PDK1 may regulate the progression of ESCC by metabolic reprogramming, which provides new strategy for the treatment of ESCC.