CTNNB1 and colon carcinoma: Two cis-acting binding elements for the beta-catenin-TCF4 complex are located in the enhancer region of the GLCE promoter, and the ectopic expression of beta-catenin-TCF4 in colon carcinoma cells produces a significant increase of GLCE transcript level and enhances the rate of D-glucuronic acid epimerization in HS, suggesting that the beta-catenin-TCF4 transactivation pathway plays a major role in modulating of GLCE expression (52).