Scientists Solved a 15 Year Mystery Behind How a Common…

Scientists Solved a 15 Year Mystery Behind How a Common Gut Bacterium Triggers Colon Cancer A specific gut bacterium has long been linked to colon cancer, but exactly how its toxin actually damages colon cells has puzzled researchers for over 15 years. A new study published in Nature, led by researchers at Johns Hopkins, finally solves that mystery, and points toward a promising new way to block the damage before it starts. Bacteroides fragilis is found in up to 20% of healthy people, generally without causing harm. But certain strains produce a toxin called BFT, which triggers chronic inflammation in the colon and can promote tumour growth. Previous research from the same lab had already shown that BFT damages the colon by cutting a protein called E-cadherin, which normally helps maintain the colon's protective barrier. That earlier work also confirmed this toxin activity directly drives colon tumour formation. What remained unclear was how the toxin actually reached E-cadherin in the first place, since it didn't appear to bind to it directly.