The role of oral microbiota in lung carcinogenesis through the oral-lung axis: a comprehensive review of mechanisms and therapeutic potential

Abstract

Abstract Purpose Growing evidence highlights the crucial role of microbial communities in tumorigenesis across various organs. As the primary gateway for microbial entry into the human body, the oral cavity harbors a complex microbiome that may significantly influence systemic health, particularly pulmonary conditions. Notably, studies reveal remarkable similarities between oral and lung microbial compositions in healthy individuals, suggesting potential crosstalk through the oral-lung axis that could impact lung tumor development. However, the precise mechanisms by which oral microbiota contribute to pulmonary carcinogenesis remain poorly understood. Understanding the relationship between oral microbes and lung tumors is important for the prevention and treatment of diseases such as lung cancer. Methods This review systematically synthesizes the latest research advances on the association between oral microbiota and lung cancer. It first elucidates the evidence demonstrating how oral microbiota promote lung carcinogenesis through the oral-lung axis, then dissects the underlying molecular mechanisms through three key dimensions: microbial metabolites, chronic inflammation, and immune regulation. Finally, it discusses potential microbiota-targeted therapeutic strategies. Results Emerging evidence establishes the oral microbiome as a key modulator of lung carcinogenesis through the oral-lung axis. Specifically, pathogens like Porphyromonas gingivalis and commensals such as Veillonella and Prevotella promote tumor progression through multiple mechanisms, including metabolite secretion, chronic inflammation induction, and immunosuppression. Furthermore, smoking exacerbates this process by significantly disrupting microbial homeostasis. Regarding therapeutic approaches, current strategies—particularly probiotics, polyphenol-rich diets, professional oral care, and phytomedicines like berberine—show considerable promise. However, these interventions still require further mechanistic validation through rigorous preclinical and clinical studies. Conclusion The oral microbiota promotes the occurrence and development of lung cancer through the oral and pulmonary axis through multiple mechanisms such as metabolite secretion, chronic inflammation induction and immunosuppression, and smoking significantly exacerbates this process by disrupting microbial homeostasis. The therapeutic effect has been preliminarily confirmed by antimicrobial therapy and probiotic intervention.

Keywords

• Antimicrobial peptides
• Inflammation response
• Lung cancer
• Metabolites
• Oral flora
• Smoking