GUT MICROBIOME AND COLORECTAL CANCER: MECHANISMS, BIOMARKERS, AND THERAPEUTIC IMPLICATIONS (A NARRATIVE REVIEW)

Abstract

Background: Colorectal cancer (CRC) remains a major cause of cancer morbidity and mortality worldwide. Emerging evidence implicates the gut microbiome as a modulator of CRC initiation, progression, and therapeutic response.

Objective: We performed a narrative review synthesizing recent mechanistic, diagnostic, and therapeutic literature on the gut microbiome–CRC axis, and highlight actionable research and clinical translation opportunities.

Methods: We conducted a focused narrative synthesis of primary research, reviews, and translational studies published between 2018–2025 across PubMed, Web of Science, and major journals.

Results: Evidence supports both tumor-promoting and tumor-protective roles of the microbiome. F. nucleatum consistently associates with CRC tissue and poorer outcomes through mechanisms including activation of Wnt/β‑catenin signaling, immune suppression, and modulation of treatment response.

Conclusions: The gut microbiome is a compelling target for CRC prevention, diagnosis, and therapeutic optimization. Standardization of sampling, mechanistic human studies, and well-powered clinical trials are needed before routine clinical translation.