Ulrik Stenz Justesen, Senior Consultant of the Department of Clinical Microbiology at Odense University Hospital, shared a post on LinkedIn:
“Did we find a major cause of colorectal cancer?
Colorectal cancer is on the rise in western countries and remains one of the most widespread and deadly cancers. While known risk factors include age, diet and lifestyle, the biological drivers behind most cases remains unknown. Growing evidence implicates the gut microbiota as a driving cause in colorectal cancer development.
In our new paper, we just published in Communications Medicine we report an association between colorectal cancer and a previously unknown bacteriophage (a virus that infects bacteria). This bacteriophage was found to infect Bacteroides fragilis, a common gut bacterium that is present in the gut of almost all healthy individuals. This is important because B. fragilis has long been linked to colorectal cancer while being widespread in people without the disease, creating a paradox.
We found that the bacteriophage infected B. fragilis were more frequently detected in the blood from patients who subsequently developed colorectal cancer. This observation was then validated in a very large independent metagenomics dataset, using faecal samples from people with and without colorectal cancer.
Genomic analyses indicate that this bacteriophage belongs to a completely new species within the Caudoviricetes class. While our findings do not prove causality, they suggest that this phage infected bacterium could be an excellent future biomarker for the early detection of colorectal cancer.
None the less, this makes you think whether or not, this combination of a bacteria and a bacteriophage might also be involved in the development of colorectal cancer? If this is the case, it opens up for a new way of looking at colorectal cancer and potential prevention and treatment.
The work was conducted at Syddansk Universitet – University of Southern Denmark and Odense University Hospital, Department of Clinical microbiology and made possible by the kind donations of HARBOEFONDEN, Novo Nordisk Foundation and Region Syddanmark.”
Other OncoDaily articles about colorectal cancer.