Specific dysbiosis characterizes CIBD-related colon cancer
The disruptions in the intestinal microbiota associated with colon cancer are not all the same, depending on whether or not the cancer is related to a chronic inflammatory bowel disease.
Among the 43,000 cases of colon cancer diagnosed every year in France, 0.4% are related to chronic inflammatory bowel diseases (CIBD), such as Crohn’s disease or ulcerative colitis. While imbalances in the intestinal microbiota have already been identified in patients with CIBD, as well as in those with colon cancer, no study had ever analyzed the dysbioses specifically associated with CIBI-related colorectal cancers.
It has now been done thanks toby a French-Italian team, which compared the composition of bacteria and fungi in the intestinal mucosa of 7 patients with CIBD-related colon cancer to that of 10 patients with a sporadic form of the same cancer and 10 healthy subjects (controls).
The researchers observed that the bacterial microbiota in the intestinal mucosa was different in cases of CIBD-related colon cancer when compared to sporadic forms and healthy subjects. However, the fungal microbiota was not affected. Patients with CIBD-related colon cancer had higher concentrations of enterobacteria and Sphingomonas and lower concentrations of Fusobacterium and Ruminococcus when compared to patients with sporadic colon cancer.
This observation suggests that there is a microbiological “signature” of MIBD-related colon cancers compared to sporadic colon cancer.
Richard ML et al. Mucosa-associated microbiota dysbiosis in colitis associated cancer. Gut Microbes. 2017 Sep 15:0.