Biofilms and beyond: The impact of Porphyromonas gingivalis on oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) appears as a very common type of head and neck cancer across the world in the recent past. The widespread use of contemporary diagnostic and prognostic methods, a low rate of survival (approximately five-year), a relatively higher chances towards recurrence, and a wide range of malignancy along with metastases are still caused by delayed diagnosis and treatment resistance. There is growing evidence that oral microbiome bacteria, including the Gram-negative anaerobic Porphyromonas gingivalis, may be important in the development of OSCC by causing periodontitis. In fact, the activity of a dysbiotic microbiota has been linked to the epithelial-to-mesenchymal transition (EMT) and dysregulated immune response. Conversely, organisms that are typically thought of as oral commensals, including streptococci from the mitis group, are frequently negatively correlated and have anticancer qualities in vivo. This chapter summarizes the role of P. gingivalis in OSCC initiation, progression, invasion, and metastatic dissemination, highlighting its contribution to microbial dysbiosis, immune modulation, epithelial-mesenchymal transition, and tumor microenvironment remodelling. Several reports have showed a positive correlation exist between the bacteria present in the periodontal part along with oral carcinoma. This would in turn pave the way for future researchers to target P. gingivalis as a potential therapeutic cornerstone to combat the life-threatening diseases.