Role of oral microbiome in modulating immune response in oral cancer development. a systematic review

BACKGROUND: Oral squamous cell carcinoma, the most common head and neck cancer, is characterized by aggressive invasion, frequent lymph node metastasis, and high recurrence. OBJECTIVE: This review explores the role of microbial dysbiosis in shaping the immune landscape of oral squamous cell carcinoma. It aims to identify key microbial taxa altered in Oral squamous cell carcinoma, examine the immunological pathways they influence, and assess their impact on tumor progression and immune evasion. METHODS: = 169). After screening and eligibility assessment, 17 studies meeting inclusion criteria were selected for final analysis. RESULTS: Fusobacterium was the most frequently enriched genus in Oral squamous cell carcinoma, followed by Peptostreptococcus, Prevotella, Porphyromonas, Campylobacter, Treponema, Capnocytophaga, and Dialister. Streptococcus was the most consistently depleted, along with Rothia, Veillonella, Leptotrichia, Capnocytophaga, and Neisseria. CONCLUSION: Cancer remains a leading cause of death. Oral microbial dysbiosis, with loss of beneficial species and enrichment of pathogens, has been linked to oral cancer, but its mechanistic role remains hypothetical and requires validation.