Could This Toxin Be Behind the Rise of Early Onset Colon Cancer?

Yahoo

29-04-2025

It's still not clear why colon cancer cases continue to rise among young people — but researchers may have come across a lead.
A new study has identified a potential culprit: a toxin called colibactin that's capable of altering DNA. Scientists found that exposure to this gut bacteria in early childhood can lead to mutations within colon cells, which could be what's causing so many young adults to develop colorectal cancer (CRC).
Here's a closer look at this fascinating new research and what it tells us about this potential carcinogen.
The study, which was published last week in Nature, examined tissue samples from nearly 1,000 CRC patients spread across four continents. The team discovered that colibactin leaves behind a specific pattern of DNA mutations, and that patients who developed the disease before the age of 40 were more than three times as likely to exhibit this genetic hallmark than those who were diagnosed after 70.
The researchers were also able to trace when these mutations arose, and the scientists believe that they're most likely acquired by the age of 10. That could put these patients 'decades ahead of schedule for developing colorectal cancer, getting it at age 40 instead of 60,' the study's senior author, Ludmil Alexandrov, says.
Colibactin is a bacterial toxin that's produced by certain strains of Escherichia coli, or E. coli, and other gut bacteria. Previous studies have shown that the toxin has the potential to damage the DNA of cells within the colon.
But this latest research raises the question: If colibactin is triggering CRC-related mutations in childhood, why are more children being exposed to the toxin? Alexandrov tells NBC that 'there are several plausible hypotheses.' One is early antibiotic use, 'which may allow these strains to establish more easily,' he says. Another contributing factor could be the increase in ultraprocessed foods in our diets, the decrease in fiber, and rising rates of C-section births.
'Collectively, these shifts may be tipping the balance towards early-life acquisition of these microbes,' he says.
Alexandrov and his team are in the process of developing stool tests to detect colibactin-related mutations and are investigating whether probiotics could help eliminate harmful strains of bacteria.
The post Could This Toxin Be Behind the Rise of Early Onset Colon Cancer? appeared first on Katie Couric Media.