Microbial Duality in Cancer: Diagnostic and Therapeutic Frontiers in CRC and OPC Microbiomics

The human microbiome orchestrates key mechanisms that uphold bodily stability and immune harmony, it actively modulates metabolic and immunological systems to preserve homeostasis. Recent studies delineate the microbiome’s context-dependent role in cancer, wherein specific microbial taxa may potentiate tumorigenesis or, conversely, exert immunoregulatory and therapeutic effects. This review examines microbiome–host crosstalk with emphasis on emerging diagnostic and therapeutic modalities in colorectal and oropharyngeal cancers(OPC). Microbiota dysbiosis can have profound effects on colorectal cancer (CRC), Fusobacterium nucleatum and Porphyromonas gingivalis are representative examples of this matter. Disrupting mucosal integrity, triggering inflammatory cytokines (e.g., IL-6, TNF-α), and suppressing tumor inhibitors (p21/p27/FAS) with G-protein-coupled receptor pathways are some of the known mechanisms of this microbiota. In this context, fecal microbiota transplantation (FMT) can use Lactobacillus species to counteract these effects through butyrate-induced apoptosis and mucosal barrier repair. It is shown that a microbial paradox emerges in OPC, resulting from Oral dysbiosis dominated by F. nucleatum, which accelerates HPV/EBV-associated lesions via NF-κB activation, yet the same bacterium demonstrates tumor-suppressive potential in engineered environments, reducing OPC cell viability greatly. The body’s sophisticated architecture focuses innate immune responses on microbiome-regulated immune checkpoint molecules. Shared metabolic pathways—such as Wnt/β-catenin in CRC and PI3K/Akt in OPC—are disrupted by pathogens but increasingly reversible through precise microbiome engineering. This review underscores the importance of understanding the microbiome and its host interactions, particularly regarding the dysbiosis evident in colorectal and oropharyngeal cancers. Therefore, the implications of microbiome research are reshaping approaches to cancer diagnostics and treatment. The identified paradoxes within microbial interactions in different cancer contexts call for further investigation into tailored therapeutic interventions

کلیدواژه ها:

Microbiota ، Colorectal Cancer ، Fusobacterium nucleatum ، Porphyromonas gingivalis