Altered intestinal microbiota associated with colorectal cancerOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This case-control study asked how the gut microbiota differs in colorectal cancer (CRC) compared with normal colons. Researchers sampled the mucosal-luminal interface of each participant. They used 16S rRNA gene amplicon sequencing to profile bacteria. They also applied PICRUSt to predict microbial functional profiles from the sequence data. The goal was to find bacterial changes that could serve as biomarkers of early carcinogenesis.
Who was studied?
A total of 23 human subjects were enrolled. Nine had colorectal cancer and formed the CRC group. Fourteen had normal colons and formed the normal group. All participants were adults, and the cohort spanned middle-aged and older ages. The study was conducted in China. Sampling targeted the colonic mucosal-luminal interface rather than stool alone.
What were the most important findings?
The gut microbial composition differed between the CRC and normal groups. CRC patients showed a significant reduction in Eubacterium, a butyrate-producing genus. They also showed a significant increase in the genus Devosia. These two shifts stood out as the clearest taxonomic differences between the groups. The authors propose that the abundance of Eubacterium and Devosia may act as candidate biomarkers for colorectal carcinogenesis.
What are the greatest implications of this study?
The results suggest specific bacteria may signal colorectal cancer, potentially aiding early detection. Loss of butyrate-producing Eubacterium fits a broader pattern of depleted beneficial fermenters in CRC. The sample was small, with only nine cancer cases, so the findings need validation in larger cohorts. The design is observational and cannot establish that these bacteria cause cancer.