Oral microbiome as a new research-target for supportive care and precision oncology

Abstract

Purpose of reviewA growing number of studies demonstrate the oral bacterial shift in cancer patients and the enrichment of oral bacteria in distant tumours. During the oncological treatment, opportunistic oral bacteria correlate with oral toxicities. This review focused on the most recent studies to identify which genera are the most mentioned and deserved further investigation.Recent findingsThis review evaluated bacterial changes in patients with head and neck, colorectal, lung and breast cancer. Greater composition of disease-related genera (e.g., Fusobacterium, Porphyromonas, Lactobacillus, Streptococcus, and Parvimonas) are present in the oral cavity of these groups of patients. The tumour specimen characterisation of head and neck, pancreatic and colorectal cancer also describes the presence of oral taxa. No evidence indicates that commensal oral bacteria have protective roles in distant tumours. Regardless, oral care is critical to prevent the growth of oral pathogens and reduce infection foci.SummaryRecent evidence suggests that oral microbiota is a potential biomarker for oncological clinical outcomes and oral toxicities. Currently, the literature presents a remarkable methodological variety - from the sample collection site to the preference of the data analysis tools. For the oral microbiome to achieve the stage of being used as a clinical tool in the oncological context, more studies are necessary.

Oral Microbial Profile Analysis in Patients with Oral and Pharyngeal Cancer Reveals That Tumoral Fusobacterium nucleatum Promotes Oral Cancer Progression by Activating YAP

“…Typically found in the mouth, as well as in the urogenital tract and intestine, it usually behaves as an opportunistic pathogen. However, it is frequently detected in colorectal, oral, pancreatic, esophageal, and other cancers [12][13][14]20]. F. nucleatum is renowned for promoting tumors via the activation of the Wnt/β-catenin pathway [20,25].…”

“…Conversely, oral bacteria play roles in oral conditions like periodontal disease and dental caries and can impact the entire body by causing bacteremia and septicemia, including infective endocarditis [11]. Recent studies have highlighted that oral bacteria, such as periodontopathogens, including Fusobacterium species, are implicated in not only oral malignancies but also in distant cancers like colorectal, esophageal, and pancreatic cancers [12][13][14]. However, there is a limited body of research elucidating the mechanism by which the oral microbiota affects the progression of head and neck cancers, including oral and pharyngeal cancers.…”