Characterization of Gut Microbiota Composition in Colorectal Adenoma and Carcinoma Patients Compared to Healthy Controls

Abstract In this study, we aimed to elucidate the role of the gut microbiome in the multistage progression of colorectal cancer (CRC). We analyse the gut bacterial composition of three clinical groups: healthy individuals, patients with precancerous polyps (adenomas), and patients with cancerous tumours (carcinomas). Biopsy samples were profiled using the Illumina MiSeq platform. Significant differences in the composition of the gut microbiota emerged between the groups. The tumour-associated microbiome showed increased bacterial diversity and specific enrichments, including Verrucomicrobia (genus Akkermansia) and specific Bacteroidetes (genera Porphyromonas and Prevotella). In contrast, the healthy group exhibited a higher abundance of specific protobacteria (genus Microvirga). In particular, the adenoma group also showed elevated levels of specific bacteria compared to the control group. Our findings suggest a possible link between the gut microbiome and the progression of CRC, with variations observed at different stages of the disease. This opens avenues for further investigation of the potential of the gut microbiome as a biomarker and therapeutic target for prevention and management.