×

Browse

Gut Bacteria: A Marker for Colon Cancer?

EMERGING research has identified a correlation between the presence of a specific bacteria in the gut microbiome and colon cancer. The elevated levels of this bacteria is thought to indicate a greater risk of colon polyps becoming cancerous. 

William DePaolo, Associate Professor at the University of Washington School of Medicine (UWSOM), USA, conducted a study of 40 patients who had previously undergone colonoscopies. The patients involved also had mucosal polyp biopsies taken to detect which bacteria were present at higher levels compared to individuals with no polyps. Scientists identified that Bacteroides fragilis levels were increased in patients with polyps, as well as discrete microbial patterns that distinguished patients with polyps to those without. 

When further examined, DePaolo and researchers discovered that B. fragilis in patients with polyps had an altered capability to cause inflammation compared to that in patients without polyps. “The whole idea is that most people look at advanced colorectal cancer and think of the microbiome, but it’s hard to determine if the microbiome has changed and when it changed,” DePaolo explained. “What our data suggests is that, in order to survive within an environment where metabolic and inflammatory changes are occurring, a normally healthy gut and related bacteria may adapt in such a way that causes it to contribute to the inflammation rather than suppress it,” he added. 

Researchers suggested that new colon cancer screenings could look to identify bacteria in the gut, particularly the amounts of B. fragilis strain, prior to polyp development. This method could be a key strategy to reducing the incidence of colorectal cancer, which is currently the third leading cause of cancer in the USA. Moving forward, DePaolo spoke of aims to expand the study to 200 patients. This will allow researchers to establish whether a faecal sample would be an effective means of biopsy.