administration exacerbated the development of colitis-associated colorectal cancer in mice.

Colorectal cancer (CRC) is one of the most common digestive tract malignancies and inflammation and gut microbiota are well-known key factors to influence CRC development. is an important gram-negative anaerobic bacterium that can degrade mucin in gut. Previous studies suggested that may affect inflammation and cell proliferation, but the relationship between and CRC is not clarified. Here C57BL/6 mice were administrated with or PBS and then treated with azoxymethane (AOM)/dextran sodium sulphate (DSS) to induce CRC. The mice receiving administration had more serious weight loss, shorter colon length and more intestinal tumors than those receiving PBS administration after AOM/DSS treatment. More colon damage and less goblet cells were also observed in treated mice. Furthermore, administration induced more Ki67 proliferating cells, higher PCNA expression and elevated gene expression of proliferation-associated molecules including , or . At early stage of CRC development, in comparison with controls, the mice receiving administration also had more body weight loss and shorter colon length, as well as higher gene expression of inflammatory cytokines. Furthermore, the experimental results showed that the co-culture of colon epithelial cells with enhanced the cell proliferation and gene expression of proliferation-associated molecules. Therefore, may promote the formation of CRC in mice through increasing the early level of inflammation and the proliferation of intestinal epithelial cells.