MSH2 and colorectal carcinoma: However, Bultman et al. [26] believed that butyrate is a causative factor of CRC, and a study on APCMin/+MSH2−/− mice fed butyrate showed that the amount of butyrate administered was positively correlated with polyp formation in mice, which might be due to the stimulation of gut microbiota hyperproliferation and mouse intestinal epithelial cell transformation through metabolites.