In Spain, cancer continues to be one of the main causes of morbidity and mortality. It is estimated that the number of cancer cases diagnosed in our country in 2021 was 276,239, according to data from the Spanish Network of Cancer Registries (REDECAN). The most frequent cancers diagnosed in Spain were those of the colon and rectum, 43,581 new cases, prostate, 35,764 new cases, and breast, 33,375 new cases.
A group of scientists from Yale University have discovered that strains of the microbe ‘Morganellamorganii’ produce toxic molecules for human DNA. The assay has been tested in mice, showing that these substances caused tumors in these animals. These toxic molecules, called indolimines, are a type of bacteria common in the intestine and could be one of the causes of colon and rectum cancer.
Noah Palm, lead scientist on the trial, acknowledges that indolimines may have an effect on colorectal cancer, but more study is needed. “Although there is an increase in this bacteria in patients with inflammatory bowel disease or colorectal cancer, it is also found in apparently healthy people”, says Palm.
It is important to note that Morganellamorganii is a type of microbe that is found in the environment and in the human intestine and sometimes causes urinary, gynecological and nosocomial infections. Noah Palm highlights the role of environmental factors in the vast majority of colon cancer cases. “Environmental factors, including the microbiome, play a key role in most colorectal cancer cases; however, it is still impossible to calculate the relative importance of the microbiome, especially against other environmental factors”, explains the author.
Risk factors for colorectal cancer
The risk of colorectal cancer increases with age. In most cases, colon cancer usually appears in people over 50 years of age. The factors that can increase the risk of suffering from this disease are aging, poor diet, family history, smoking or inflammatory bowel diseases.
CayetanoPleguezuelo, a Spanish biotechnologist, applauds the good work of the group of American scientists. “This new technique opens the door to evaluating many bacteria and their ability to damage DNA”,Pleguezuelo points out. Colon cancer is the third most common type of cancer diagnosed worldwide. In effect, the scientists point out that this is just one study and more trials must be carried out to obtain definitive results. Still, any progress in the fight against cancer is encouraging.