Frontiers in Cellular and Infection Microbiology · Oct 30, 2026
Dynamic Alterations of the Oral-Gut Microbiome during Colorectal Adenoma Progression and Their Clinical Associations
By 书凝 丁, Chenwei Xiao, Qingyang Liu et al.
Background: The "oral-gut axis" drives colorectal tumorigenesis, yet cross-niche microbial succession during early precancerous adenoma progression remains poorly understood. Methods: We performed 16S rRNA amplicon sequencing on matched salivary and fecal samples from 81 individuals spanning three histopathological stages: normal mucosa, low-grade intraepithelial neoplasia (LGIN), and high-grade intraepithelial neoplasia (HGIN). Compositional dynamics, clinical phenotype correlations, and predictive capabilities were comprehensively assessed using bioinformatics and multi-class Random Forest modeling. Findings: Adenoma progression was characterized by progressive ecological destabilization. The gut microbiome exhibited early systemic depletion of core short-chain fatty acid-producing networks (e.g., Faecalibacterium, Roseburia). Concurrently, shared cross-niche pathobionts, notably Fusobacterium and Streptococcus, displayed dynamic abundance patterns highly correlated with systemic host inflammation and clinical parameters. Multi-class classification models demonstrated excellent discriminatory performance, with the fecal model achieving area under the curve (AUC) values >0·91 for predicting both normal and HGIN statuses. Interpretation: Stepwise structural reorganization of the oral-gut microbiome is a hallmark of colorectal adenoma progression. Mining these dynamic, cross-niche microbial signatures provides a critical theoretical foundation for non-invasive early screening strategies and precision microbiota-directed interventions.