Increasing evidences have shown that intestinal microbiota may contribute to the etiology of colorectal cancer(CRC). Studies have shown some microbial species which can increase the risk of CRC. Intestinal bacteria can promote carcinogenesis by affecting DNA integrity,regulating immune reaction,inducing inflammation,increasing cell proliferation and altering stem cell dynamics. Modulation of intestinal microbiota may become an approach to prevent or treat CRC. This article reviewed the effect and mechanism of intestinal bacteria flora on CRC.

0.05).The morbidity of AAD was obviously lower in group B than that in group A(P