HINT1 and cancer: A recent study revealed that ectopic expression of the acetylation mimetic HINT1 mutant (HINT1 K21Q; lysine to glutamine or K21D; lysine to aspartate) promoted colony formation in soft agar but did not promote cell proliferation compared to that with wild-type HINT1 expression in cancer cells derived from melanoma patients16, indicating that acetylation of HINT1 might affect cell migration.