Metagenomic and metabolomic analyses reveal distinct stage-specific phenotypes of the gut microbiota in 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 study examined the gut microbiome and fecal metabolome across the stages of sporadic colorectal cancer development, from multiple polypoid adenomas through intramucosal carcinoma to more advanced lesions. Researchers used fecal metagenomic sequencing paired with metabolomic profiling to characterize taxonomic, functional, and metabolite changes at each stage. The goal was to identify stage-specific microbial and metabolic phenotypes rather than treating colorectal cancer as a single uniform condition.
Who was studied?
The analysis drew on fecal samples from a large cohort of 616 participants who underwent colonoscopy. This allowed the researchers to classify individuals by lesion stage, including multiple polypoid adenomas, intramucosal carcinomas, and more advanced colorectal lesions. The cohort size and colonoscopy-based staging gave the study a broad basis for comparing microbiome and metabolome features across the adenoma-to-carcinoma continuum.
What were the most important findings?
Two distinct microbial patterns emerged: Fusobacterium nucleatum abundance rose significantly and continuously from intramucosal carcinoma through more advanced stages, while Atopobium parvulum and Actinomyces odontolyticus co-occurred and increased specifically in multiple polypoid adenomas and intramucosal carcinomas but not beyond. Metabolome analysis showed branched-chain amino acids and phenylalanine were significantly elevated in intramucosal carcinomas. Bile acids, including deoxycholate, were also significantly increased in multiple polypoid adenomas and intramucosal carcinomas, marking an early metabolic shift alongside the microbial changes.
What are the greatest implications of this study?
The findings suggest that gut microbiota and metabolite alterations are not uniform across colorectal tumorigenesis but instead follow distinct, stage-specific trajectories. Because Atopobium parvulum, Actinomyces odontolyticus, and elevated bile acids like deoxycholate appear early, in adenomas and intramucosal carcinomas, they may serve as candidate markers for early lesion detection. The continuous rise of Fusobacterium nucleatum with advancing stage suggests it may instead track disease progression, supporting stage-specific rather than one-size-fits-all microbiome-based screening strategies.