New research reveals that a common germ found in the human mouth can migrate to colon tumors and potentially accelerate their growth. This discovery holds promise for advancing our understanding of colon cancer, a disease claiming over 52,000 lives annually in the United States, according to the American Cancer Society.
Scientists at the Fred Hutchinson Cancer Center in Seattle investigated levels of a specific oral bacterium, Fusobacterium nucleatum, within colon tumor tissues from 200 patients with colon cancer. They identified a particular subtype, Fna C2, which was associated with tumors rather than healthy tissue. This subtype was also more prevalent in stool samples from colon cancer patients compared to those from healthy individuals. The findings were reported in Nature.
Co-corresponding study author Susan Bullman, a cancer microbiome researcher at the center, emphasized the link between Fusobacterium nucleatum in colorectal tumors and poor patient survival. Bullman suggested that targeting this microbial subgroup could improve outcomes for individuals at higher risk of aggressive colorectal cancer.
The researchers discovered that only the Fna C2 subtype of Fusobacterium nucleatum, among various subtypes found in the mouth, could travel from the oral cavity to the stomach and then colonize the lower gastrointestinal tract, including the colon. Approximately 50% of the tested colon tumors exhibited the presence of this particular subtype.
Bullman’s group proposed that microbe-based “cellular therapies” could represent a novel approach to combat colon cancer. These therapies involve modified bacteria delivering medications directly to tumors. Co-corresponding author Christopher Johnston, a molecular microbiologist at Fred Hutch, underscored the importance of identifying the specific bacterial lineage associated with colorectal cancer for the development of effective prevention and treatment strategies.
