Yes, a specific bacteria in your colon could possibly cause colon cancer.  Colon cancer is common, affecting more than 150,000 Americans every year, and 40% of them will die from the cancer.

Normal colon bacteria are possibly involved in the development of colon cancer.  A specific bacteria in the colon, called Enterococcus faecalis has been implicated in the development of colon cancer.  Enterococcus faecalis can produce superoxide molecules called “oxygen radicals” that can damage the DNA in the cells that line the inside of the colon.
Scientist have found that the oxygen radicals produced by these bacteria can alter the manner in which the colon cells grow and divide, and may alter the DNA, inducing mutations that can cause colon cancer.
This is according to a study from the Journal of Medical Microbiology.  Scientists identified 42 different genes within colon cells that could be affected by this bacteria and lead to colon cancer.

Although it is intriguing to contemplate a specific bacterial as the cause of colon cancer, it is not that easy.  Enterococcus faecalis is a normal part of the colon flora, so everyone has this organism and not everyone develops colon cancer.

More studies are needed to confirm a relationship between Enterococcus faecalis and colon cancer and whether treating with antibiotics could lower rates of colon cancer.

Cristopher Geiler, MD
Reference
http://jmm.sgmjournals.org/