A subtype of bacteria involved in gum disease may increase the risk of developing aggressive colorectal cancer, according to a new study.
- Scientists have identified a specific subtype of bacteria involved in gum disease, which is associated with colorectal cancer.
- This is a type of F. nucleatum bacteria called Fna C2.
- For the team, the discovery could lead to therapies targeting these bacteria in colorectal tumors and improve screening.
What if the origin of the increase in colorectal cancers was in the oral microbiota? This is what a study published in the journal suggests NatureMarch 20, 2024.
Researchers have discovered that a bacteria present in the mouth and involved in gum disease promotes the growth of colorectal tumors.
Oral microbiota: the F. nucleatum bacteria associated with colorectal cancer
To better understand the presence of the bacteria Fusobacterium nucleatumknown to be involved in gum disease, in certain colorectal cancer tumors, researchers analyzed the genomes of 80 strains of F. nucleatum from the mouths of people without cancer and 55 strains from colorectal tumors.
They thus discovered that a subspecies of the bacteria, called Fna, was more likely to be present in colorectal tumors. Additional examinations revealed that there were two distinct types. If both were present in the mouth, the one baptized Fna C2was associated with colorectal cancer.
The team then carried out tests on mice, divided into two groups. Each was infected with one of two types of F. nucleatum. Results: rodents carrying Fna C2 had developed more tumors than those infected with the other type.
Colorectal cancer: the bacteria passes through the digestive tract
How the bacteria in the oral microbiota travels from the mouth to the colon remains mysterious. However, researchers have demonstrated that the microorganism Fna C2 could survive longer in acidic conditions, such as those found in the intestine, than the other type of Fna. It would therefore be possible for it to travel via the digestive tract.
“We have identified the exact bacterial lineage associated with colorectal cancer”explains Christopher D. Johnston of the Fred Hutchinson Cancer Center and head of research, “and this knowledge is essential to the development of effective prevention and treatment methods.”
For scientists, their discovery could, among other things – through additional research – help identify the colorectal tumors most likely to be aggressive and target them directly.
