Scientists Have Found The Type Of Bacteria That Increase The Risk Of Bowel Cancer

Scientists have found the type of bacteria that increase the risk of bowel cancer

People who have a certain type of bacteria in their gut are at increased risk of colon cancer, according to a study by the University of Bristol.

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People who have a certain type of bacteria in their gut are at increased risk of colon cancer, according to a study by the University of Bristol. The results of the study, not yet published, were presented at a conference at the National Cancer Institute in Glasgow.

The gut microbiome (the community of microorganisms living in it) is genetically determined and is unique to each person. It is relatively stable throughout a person's life, but can change under the influence of antibiotics, diseases, or changes in diet.

“Plenty of studies in mice and humans have shown a link between the gut microbiome and bowel cancer, but very few have provided conclusive evidence for a causal relationship. In other words, it is really difficult to determine whether components of the gut microbiome can cause bowel cancer, whether the disease itself is causing a change in the gut microbiome, or whether the link is due to some other factor,”said Kaitlin Wade, who presented the results of the study at conferences.

Mendelian randomization was used for the first time to investigate the causal role of bacteria in the development of bowel cancer. This method improves the reliability of the study.

Scientists analyzed data on the gut microbiome of 3,890 people from three European studies. They found 13 genetic variants (for example, certain mutations) associated with the presence of certain bacteria in the gut in study participants.

For further work, the scientists used data on 120328 participants in a large study of genetics and the prevalence of colon cancer: that is, it was known whether these people had cancer and what genes they carry.

The authors could partially predict the composition of the microflora of these people, based on the presence of certain genetic variants. It turned out that in people in whose intestines there are bacteria of the Bacteroidales group, the risk of intestinal cancer was 2-15% higher.

According to the scientists, the results obtained confirm the data of previous studies, according to which the bacteria Bacteroidales are more common in people with bowel cancer.

However, many questions remain, in particular whether genetic variants associated with gut bacteria are directly responsible for the increased risk of bowel cancer. It is possible that these options lead to a preference for certain types of food that have a direct impact on the risk of bowel cancer or on the composition of the microbiome.

Scientists plan to conduct further research to identify specific types of Bacteroidales associated with bowel cancer. It is also necessary to find out if changing the number of these microbes can reduce the risk of bowel cancer.

“The stability of the gut microbiome is questionable and there are complex relationships between the types and amounts of bacteria present, so it is too early to attribute causality to the reported results. However, similar larger studies have the potential to significantly improve our understanding of how bowel cancer develops,”summarized Ian Tomlinson, director of the Edinburgh Center for Cancer Research and a member of the conference's scientific committee.