Gut microbes 'link to bowel cancer'
An imbalance of gut bacteria may increase the risk of bowel cancer, research suggests.
Scientists found that patients with the disease had fewer "friendly" bugs and more harmful bacteria than healthy people.
Study leader Dr Jiyoung Ahn, from New York University Cancer Institute in the United States, said: "Our findings are important because identification of these microbes may open the door for colorectal cancer prevention and treatment."
Many thousands of bacteria live in the human gut, playing an important role in regulating food digestion and inflammation.
Increasing evidence links gut microbes to colorectal, or bowel, cancer.
The researchers compared the DNA of intestinal microbes in the stool samples of 141 bowel cancer patients and healthy volunteers.
They found that patient samples had larger populations of Fusobacteria - a type of bug commonly found in the mouth and gastro-intestinal tract associated with gut inflammation.
At the same time the bowel cancer patients were more likely to be lacking Clostridia, a class of "friendly" gut bacteria that help digest dietary fibre and carbohydrates.
"Our next step is to study how diet and lifestyle factors modulate these gut bacteria associated with colorectal cancer," said Dr Ahn. "This may lead to ways to prevent this disease."
The findings are reported in the Journal of the National Cancer Institute.