Fusobacterium nucleatum and non-coding RNAs: orchestrating oncogenic pathways in colorectal cancer.

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality worldwide, with mounting evidence implicating the gut microbiome in its pathogenesis. Among the microbial agents, Fusobacterium nucleatum has emerged as a prominent contributor, frequently detected in CRC tissues and associated with advanced disease stages and poor prognosis. This review highlights the complex interplay between F. nucleatum and host non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in modulating CRC biology. F. nucleatum influences the expression of several ncRNAs, which in turn regulate key signaling pathways such as Wnt/β-catenin (e.g., miR-1246, miR-135b), PI3K/AKT (e.g., miR-22, miR-135b), and TLR4/NF-κB (e.g., miR-31, lnc-NEAT1). Through these mechanisms, F. nucleatum contributes to tumor cell proliferation, immune evasion, metastasis, and chemoresistance. Additionally, its impact on ncRNA expression is implicated in reduced efficacy of standard chemotherapy. Emerging microbiota-based therapies, including probiotics and fecal microbiota transplantation, show promise in modulating gut flora and potentially reversing ncRNA dysregulation; however, their mechanistic effects on the F. nucleatum-ncRNA axis require further investigation. This review underscores the critical role of F. nucleatum-regulated ncRNAs in CRC and presents new opportunities for biomarker discovery and targeted therapeutics.