Evidence has long suggested an association between mouth bacteria that enters the bloodstream via bleeding gums and serious infections of the brain, liver, and heart, as well as preterm birth in pregnant women.
The presence of the bacterium, known as ‘fusobacterium nucleatum’, has also been shown to be very high in bowel tumours.
According to research conducted in 2012, fusobacterium use a sugar-binding protein to stick to developing bowel polyps and cancers and cause them to grow.
This month, new research conducted at Virginia Tech and published in Science Signaling revealed infection with these bacteria also causes the cancer cells to spread within the body.
The findings are significant because 90 percent of cancer-related deaths result from non-primary tumours or sites that have metastasised to somewhere else in the body.
The long-term goal of the Virginia Tech researchers is to advance cancer treatment by addressing the role bacteria play in disease, which could be a critical piece that has been missing from the puzzle.
“We need to know if there are other important bacteria that could be working in synergy with F. nucleatum to drive cancer,” said Associate Professor Scott Verbridge.
“We need to understand the physiological role of these bacteria as we can’t just go about clearing them from the body because we need them for some situations.”
Bacteria are often needed for chemotherapy to be fully effective.
“I also think it’s interesting to ask if the bacteria are causing this cellular migration as a way to get around in the human body.
“There could be a selective advantage for any infectious agent, a virus or bacteria, that could get inside of a host cell and migrate.”
As well as worsening cancer, fusobacterium have been found to worsen the bowel condition ulcerative colitis, which in turn is linked to cancer.
Regular tooth brushing is one way of reducing that risk, by removing the bacteria before it relocates.
However, the presence of fusobacterium in the gut, or its absence, is not a direct indicator of someone’s toothbrushing habits.
The microbes that live in a person’s mouth and gut are influenced by many things – toothbrushing is just one of them
Source: Virginia Tech