The role of oral microbiota in oral cavity squamous cell carcinomas

Aim: Oral cavity cancers have a relatively high survival rate when detected early. Although treatment has improved in recent years, early diagnosis is still very important for a better prognosis. The oral cavity serves as one of the largest microbial reservoirs in the human body, and microbial variations in the oral cavity are highly associated with malignancies. The aim of our study was to evaluate the role of oral microbiota in oral cavity cancers and whether targeting them would provide diagnostic, prognostic or therapeutic benefits. Materials and Methods: Our study included 20 patients with confirmed pathological diagnosis of OSCC between 2024-2025 and 20 healthy controls. Samples were taken from tumor tissue in the study group and from intact mucosa in the healthy group using a sterile swap method. The samples were delivered to the laboratory for DNA extraction and purification. The isolated DNA was then used in an amplicon-based metagenomic study and next-generation sequencing (NGS) was performed. Metagenomic bioinformatic analysis of V3-V4 amplicon sequences was performed. The composition and abundance of bacterial species between the groups were compared.targeting them would provide diagnostic, prognostic or therapeutic benefits. Results: Capnocytophaga, Alloprevotella, TM7x (Candidatus Saccharibacteria), Prevotella, Gemella and Treponema were found more in the patient group compared to the control group. In the control group, Veillonella, Streptococcus, Haemophilus, Hoylesella and Lautropia genera were detected at higher rates. Phocaeicola and Parvimonas genera were observed to be found at higher rates in the patient group, while Oribacterium, Mycoplasma and Filifactor genera were detected more dominantly in the control group. Conclusion: Findings indicate a possible relationship between oral microbiota and carcinogenesis. Dysbiotic changes in the microbiota may affect the tumor microenvironment through mechanisms such as chronic inflammation and immune modulation. These results suggest that the microbiota is not just a passive environmental component but a potentially active contributor to the development of OSCC