c-Src phosphorylation and activation of hexokinase promotes tumorigenesis and metastasis

It is well known that c-Src has important roles in tumorigenesis. However, it remains unclear whether c-Src contributes to metabolic reprogramming. Here we find that c-Src can interact with and phosphorylate hexokinases HK1 and HK2, the rate-limiting enzymes in glycolysis. Tyrosine phosphorylation dramatically increases their catalytic activity and thus enhances glycolysis. Mechanistically, c-Src phosphorylation of HK1 at Tyr732 robustly decreases its K m and increases its V max by disrupting its dimer formation. Mutation in c-Src phosphorylation site of either HK1 or HK2 remarkably abrogates the stimulating effects of c-Src on glycolysis, cell proliferation, migration, invasion, tumorigenesis and metastasis. Due to its lower K m for glucose, HK1 rather than HK2 is required for tumour cell survival when glucose is scarce. Importantly, HK1-Y732 phosphorylation level remarkably correlates with the incidence and metastasis of various clinical cancers and may serve as a marker to predict metastasis risk of primary cancers. The protein tyrosine kinase c-Src is a renowned proto-oncogene with pleiotropic effects. Here, the authors show that c-Src induces the metabolic reprogramming of cancer cells by phosphorylating hexokinases HK1 and HK2, which in turns lead to increased HK catalytic activity and consequent enhancement of glycolysis.