Oral microbiome and cancer: A closer look at the complex interactions of the hidden world of the mouth – Medical Xpress Achi-News

The human mouth is a busy ecosystem teeming with microscopic life. Although we often associate oral health with brushing, flossing, and regular dental checkups, there is more to the story.

A recent review article published in Periodontology 2000 by researchers at Karolinska Institutet, who collaborate with researchers in South Korea, Sri Lanka and Australia, investigating the complex world of oral microbes and their potential impact on oral pathologies, including the development of cancer.

Georgios Belibasakis, Professor of Clinical Oral Infection Biology and Head of the Division of Oral Health and Periodontology in the Department of Dental Medicine, and his team discuss the oral bacteriome and mycobiome – communities of bacteria and fungi – among oral mucosal pathologies and across different stages of oral carcinogenesis. The review sheds light on the hidden players in our mouths and their connection to the causes and development of disease.

The studies discussed in the review have analyzed samples of saliva, dental plaque (biofilm), and oral mucosal tissue in various oral pathologies and at different stages of oral cancer development. Here are the key takeaways:

Cutting-edge technology metagenomic and metaproteomic platforms enable us to decipher the composition of the microbial inhabitants of the mouth, shedding light on their presence and roles in disease. In the case of oral squamous cell carcinoma (OSCC) certain bacterial or fungal species stood out.

Prevotella intermedia, Porphyromonas endodontalis, Acremonium exuviarum, and Aspergillus fumigatus were enriched, while, on the contrary, Streptococcus salivarius, Scapharca bringonii, Mortierella echinula, and Morchella septimelata were depleted in this pathology.

The microbial dysbiosis associated with OSCC was most evident in mucosal samples, rather than in biofilm or saliva samples. This highlights the importance of considering the spatial microbiome as well as the vicious cycle of the interaction between bacteria and fungi, when studying oral carcinogenesis.

Professor Belibasakis said, “Variations in an individual’s ‘core microbiome’ can be predictive markers for any oral condition, including carcinogenesis. The available data improve our understanding of the ecology of the oral niches and their ‘dysbiotic’ changes during oral mucosal dysplasia and oral cancer.

“This information could support early diagnostic and prognostic tools as well as innovative treatments, making a quantum leap in oral medicine.”

In the fight against oral cancer, understanding the complex dance of bacteria and fungi in our mouths can be a key ally for prevention and better management.