Mouth bacteria may cause colorectal cancer
How do bacteria from your gut that are found in your mouth lead to colorectal cancer? Scientists didn’t really know whether or how gut microbes caused tumor growth. But new research has found that gut microbes in the mouth can stimulate bad immune responses, which can turn on cancer growth genes and lead to the development of colorectal tumors. These microbes, known as fusobacteria, are not only present in people’s mouths, but also in other tissues collected from colorectal cancer patients. Researchers say they were able to directly link these microbes to the formation of tumors.
The research found that fusobacteria was prevalent in human adenomas – benign tumors that can become malignant over time. Suspecting that the microbes contribute to early cancer growth, mouse models were used to test the theory. Ultimately, the researchers found that the bacteria accelerated the formation of tumors by attracting immune cells, which invade tumors and stimulate inflammatory responses. The fusobacteria attaches to and invades colorectal cancer cells, triggering cancer growth genes.
The researchers hope this discovery can be used to help identify better means of prevention, detection and treatment of colorectal cancer, which is the second leading cause of cancer-related death in the U.S.