HINT1 and malignant colon neoplasm: As HINT1 has been previously described as a tumor suppressor in several cancer cells and as an inhibitor of β-catenin activity in colon cancer and melanoma2, this study examined the physiological roles of the constitutive deacetylated HINT1 mutant (HINT1 2KR) in tumorigenesis in DLD1 and SW480 cell lines.