Mouth Bacteria and Metastatic Cancer

It has recently been discovered that a common bacteria, which resides in normal, healthy gums, may have a role in the metastasis of certain types of cancer, including colon, esophagus, pancreas and breast. Known as Fusobacterium nucleatum, the microbe is a normal component of the oral microbiome, but poor dental hygiene, uncontrolled diabetes and other conditions can cause it to spread, leading to conditions like periodontitis, tonsillitis and appendicitis.

The link to cancer was first discovered nearly a decade ago when the DNA of F. nucleatum was found to be present at higher levels in colon tumor tissue than in normal tissue. It has also been linked to poorer prognosis, chemotherapy resistance and metastasis in various types of cancer.

But in the last year, it has been confirmed that the bacteria is not just a warning sign. When colon cells are invaded by F. nucleatum, they have been found to produce two inflammatory proteins that promote metastasis, and may actually accelerate it.

These results underscore the importance of the microbiome in battling cancer as well as promoting it. It’s already been shown that some immunotherapies work better when beneficial microbes are present. And the fact that F. nucleatum is attracted to sugar on tumor cells could someday be exploited to carry therapeutic drugs directly to a malignant target. Understanding this delicate balance is fast-becoming an important component in fighting cancers.