LDHB and cancer: Previous findings have indicated that LDHB is suppressed in many kinds of cancer due to promoter hypermethylation, including prostate, gastric, and pancreatic cancer.9,18,19 Loss of LDHB in cancer cells led to elimination of LDH1 to 4 and leaved only LDH5 that was expected to catalyze the conversion of pyruvate to lactate.9 Meanwhile, it is worth noting that LDHB upregulation has been reported in the context of other tumor types.