Gut Bacteria Might be an Indicator of Colon Cancer Risk, Says Study

Upon closer examination, DePaolo found that the B. fragilis from patients with polyps differed in its ability to induce inflammation compared to the B. fragilis from polyp-free individuals.

“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 said. “So we took an earlier look at the disease and asked when might the microbiome may be pushing a polyp toward cancer.”

Also, when people think of the microbiome and its role in disease, they often think of compositional changes where a potentially dangerous bacteria takes over, he added.

“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,” DePaolo explained.

Only 5% of the polyps in the colon actually turn out to be cancerous, he said. He said polyps seem to develop in the same areas of the colon repeatedly – and he theorized that in fact new screenings for colon cancer could look for key bacteria inhabiting the gut – and the amounts of this particular strain of B. fragilis – before pre-cancerous polyps even develop.

The next step, he said, is to expand the study to 200 patients to determine whether a fecal sample might be used as a surrogate for the mucosal biopsy.

This study was supported by UW startup funds; funds from the Rodger C. Haggitt Endowed Chair Fund, R01CA220004, U01CA152756, it was also supported by a Washington Research Foundation Distinguished Investigator Award and by startup funds from the Institute for Systems Biology.

DePaolo is also the director of the Center for Microbiome Sciences & Therapeutics.

Source: Eurekalert