Colorectal polyps turn cancerous with certain bacteria present

Colorectal polyps turn cancerous with certain bacteria present

Only 5 per cent of colorectal polyps lead to colorectal cancer but it would seem that localised bacteria may be the reason for the increased inflammation when they do.

Research from William DePaolo, associate Professor at the University of Washington School of Medicine, studied 40 people in a preliminary study. All had colonoscopies, and the ones with polyps had samples of the microbiome removed from the local area.

Only 5 per cent of people with polyps end up with Colorectal cancer but the polyps occur in the same places with some consistency.

The research showed that where there was inflammation around the polyps, there were higher levels of the bacterium Bacteroides fragilis, linked to higher levels of inflammatory cytokines.

However, the B. fragilis appeared to be slightly different to the seemingly harmless B. fragilis found normally in the gut implying that either it was a different strain or other bacteria in and around the polyp were modifying the bacterium.

DePaolo plans a bigger study adding that it was important to look at the contribution of the microbiome before cancer occurred rather than once it had done, especially given the rapid growth in numbers of this cancer and its ever younger profile.


Go to: Are antibiotics the reason for increases in younger Colorectal cancers?




  1. Melissa C. Kordahi, Ian B. Stanaway, Marion Avril, Denise Chac, Marie-Pierre Blanc, Benjamin Ross, Christian Diener, Sumita Jain, Paul McCleary, Ana Parker, Vincent Friedman, Jennifer Huang, Wynn Burke, Sean M. Gibbons, Amy D. Willis, Richard P. Darveau, William M. Grady, Cynthia W. Ko, R. William DePaolo. Genomic and functional characterization of a mucosal symbiont involved in early-stage colorectal cancer. Cell Host & Microbe, 2021; DOI: 10.1016/j.chom.2021.08.013

  Approved by the Medical Board. Click Here 


2021 Research
CancerAcitve Logo
Subscribe (Free e-Newsletter)

Join Chris'

Join Chris' NewsletterSignup today for free and be the first to get notified on new updates.