For instance, in Glycolysis/ Gluconeogenesis and Biosynthesis of amino acids pathways, lysine 131 (K131) site of PGK1, K322 and K13 sites of ALDOA, K215 and K194 sites of GAPDH, K89 site of ENO1, K678 site of PFKM were hyper-lactylated in cancer cells and tissues. The gene discussed is PGK1; the disease is cancer.