In vitro studies have shown that treatment of MLH1-methylated colon cancer cell lines with the demethylating agent 5′-aza-2′-deoxycytidine (5-aza-dC) induced the expression of MLH1 and sensitized cancer cells to 5-fluorouracil (5-FU) [126]. Here, MLH1 is linked to malignant colon neoplasm.