Cancer cells are metabolically different from normal matching cells, and this is manifested by the high rate of glucose metabolism in cancer cells. The high rate of glucose metabolism in cancer cells is, at least in part, due to the marked induction of hexokinase (HK2) expression, which is not expressed in most normal cells. Most normal adult tissues and cells express hexokinase 1 (HK1), but when they convert into cancer cells, they start expressing high levels HK2. Thus, HK2 could be a hallmark of cancer cells and could be targeted for cancer therapy. Over the years we provided genetic proofs of concept that HK2 can be systemically deleted in mice to inhibit cancer without adverse consequences. We showed that HK2 deficiency inhibited both initiation and maintenance of cancer in mouse models of lung cancer, breast cancer, liver cancer, and prostate cancer. Likewise, inducible knockdown of HK2 in human cancer cells inhibited the growth of tumors after tumor formation. In this grant application we will investigate novel HK2 activities that were not previously explored. These activities include: (i) A novel moonlighting function of HK2, independently of its glucose kinase activity. This activity could determine the stability of certain proteins such as MCL1, NRF2, and SNAIL that are associated with cell survival, redox regulation, and EMT and metastasis respectively. (ii) A role of HK2 in glycosylation, tumor microenvironment and immunotherapy. (iii) The effect of HK2 on gene expression through histone lactylation.