Colorectal cancer is becoming more common among younger folks, and a new study might have found a reason why. Researchers from the University of California San Diego think a bacterial toxin called colibactin could be driving this increase. This toxin is made by certain types of E. coli bacteria that hang out in the colon and rectum.
The study suggests that if kids are exposed to colibactin early on, it can mess with their DNA, upping their chances of getting colorectal cancer before they hit 50. The research team checked out nearly a thousand colorectal cancer genomes from both younger and older patients in 11 different countries. This work was backed by Cancer Research UK and appeared in the journal Nature.
Ludmil Alexandrov, a senior author of the study, told Fox News Digital that colibactin exposure seems to be a big reason younger people are getting colorectal cancer. He pointed out that kids exposed to this toxin could end up getting cancer much earlier than expected. The study found that these young folks had certain DNA mutations, mostly happening when they’re kids, which could speed up cancer development.
The researchers discovered that people with these mutations were more likely to get colorectal cancer early, compared to those diagnosed after age 70. These mutations accounted for around 15% of the early genetic changes that increase cancer risk. Alexandrov noted, “We detected the mutational signature of colibactin in over 50% of colorectal tumors from patients under 40.”
Alexandrov emphasized how striking it is that something kids are exposed to can leave a “lasting genomic imprint” and possibly lead to cancer years later. He stressed the importance of how we care for kids and how it might impact their long-term health. Dr. Emil Lou from the University of Minnesota agreed, noting that the microbiome might play a role in early-onset cancer.
Lou, who wasn’t part of the study, mentioned how it’s becoming less shocking to find bacteria-related toxins linked to cancer. He pointed out the worrying time gap between when someone might be exposed to these bacteria and when they actually get cancer. Alexandrov acknowledged the study’s limitations, saying it’s tough to prove colibactin alone causes cancer.
Statistics show colorectal cancer cases have doubled among adults under 50 over the past two decades. Alexandrov noted the challenge in proving colibactin alone starts cancer, requiring long-term studies from childhood. Dr. Lou highlighted the complexity of cancer, with many factors possibly playing a role.
Both Alexandrov and Lou agree that while the study shows a strong link, it doesn’t prove colibactin is the main cause of cancer. The findings lay the groundwork for more research to figure out whether there’s a true cause-effect relationship. As it stands, colorectal cancer might become the top cancer killer among young adults by 2030 if things don’t change.
Alexandrov mentioned that while the findings don’t call for immediate changes in screening or treatment, they do underline the importance of early microbial exposure. His team is working on screenings to spot colibactin’s long-term effects, hoping to turn these findings into preventive measures soon.
