Microbiota and head and neck cancers: Mechanistic insights and translational potential

Head and neck cancers (HNCs) impose a substantial global health burden, particularly in Asia and China. Emerging evidence highlights the pivotal role of oral, pharyngeal, and intratumoral microbiota in HNC pathogenesis. Microbial dysbiosis promotes tumor initiation and progression through interconnected mechanisms, including chronic inflammation, immune modulation, and metabolic reprogramming. Specifically, dysbiosis induces a pro-tumorigenic microenvironment by triggering persistent inflammation, disrupting immune surveillance, and generating oncogenic metabolites or depleting protective compounds. Comparative analyses reveal both shared and site-specific microbial signatures, reflecting complex host - microbe interactions. Notably, the microbiota holds promise as a source of noninvasive biomarkers for early detection and prognosis, and may influence responses to immunotherapy and chemoradiotherapy. However, challenges remain in methodological standardization and in establishing causal relationships. Integrating multi-omics approaches with functional studies will be essential to advance precision diagnostics and microbiota-targeted strategies for personalized HNC management.