A bacterium commonly found human intentions could contribute to bowel cancer, under specific conditions, according to new research. The data reveals that a toxin called colibactin, released by a strain of Escherichia coli, triggers unique patterns, or ‘fingerprints’, of DNA that can cause damage to the cells lining the gut through a process called tumorigenesis.
The reason why there appears to be a connection is because the molecular fingerprints have also been detected in bowel cancer tumours. This evidence indicates a connection between a specific bacterial toxin and the types of genetic changes that are associated with cancer development. A further indication of the connection is with colibactin being frequently isolated from the faeces of cancer patients.
The research team ran experiments using human cells in the laboratory, showing what the effects of the colibactin are. The experimental results confirmed the hypothesis.
The implications of the research suggest that medics should focus on reducing the presence of high-risk bacteria in the gut. However, for the current time those concerned should continue to focus on exercise and with consuming a healthy diet. For those of a certain age (over 55 years is considered to be a higher risk group), it is recommended that they take part in bowel cancer screening
The research study has been published in the science journal Nature. The research paper is titled “Mutational signature in colorectal cancer caused by genotoxic pks E. coli.”
Parallel work conducted by the Hubrecht Institute has shown that cancer mutations of the colon can also be triggered by genotoxic E. coli, through the organisms inducing a unique mutational pattern in human DNA. As with the bowel cancer study, colibactin was the attributable cause.
