Oral Bacterial Microbiota in Digestive Cancer Patients: A Systematic Review

Abstract

The relation between the gut microbiota and human health is increasingly recognized. Recently, some evidence suggested that dysbiosis of the oral microbiota may be involved in the development of digestive cancers. A systematic review was conducted according to the PRISMA guidelines to investigate the association between the oral microbiota and digestive cancers. Several databases including Medline, Scopus, and Embase were searched by three independent reviewers, without date restriction. Over a total of 1654 records initially identified, 28 studies (2 prospective cohort studies and 26 case-controls) were selected. They investigated oral microbiota composition in patients with esophageal squamous cell carcinoma (n = 5), gastric cancer (n = 5), colorectal cancer (n = 9), liver carcinoma (n = 2), and pancreatic cancer (n = 7). In most of the studies, oral microbiota composition was found to be different between digestive cancer patients and controls. Particularly, oral microbiota dysbiosis and specific bacteria, such as Fusobacterium nucleatum and Porphyromonas gingivalis, appeared to be associated with colorectal cancers. Current evidence suggests that differences exist in oral microbiota composition between patients with and without digestive cancers. Further studies are required to investigate and validate oral–gut microbial transmission patterns and their role in digestive cancer carcinogenesis.

Periodontitis pathogen Porphyromonas gingivalis promotes pancreatic tumorigenesis via neutrophil elastase from tumor-associated neutrophils

“… 7 Notably, clinical observations have demonstrated that the prevalence of PC significantly increases in chronic periodontitis patients. 8 , 9 Porphyromonas gingivalis ( P. gingivalis ), a keystone oral-resident periodontal pathogen, was reported not only being involved in the oncogenesis of several gastrointestinal cancers, 10 such as esophageal cancer 11 and colorectal cancer, 7 but also being epidemically correlated with PC. 12–14 These observations suggest the potential causative link between periodontitis and PC might be mediated by P. gingivalis .…”

Gut Microbiota Association with Diverticular Disease Pathogenesis and Progression: A Systematic Review

“…Taking part in the digestion process, the intestinal microbiota synthetizes essential amino acids and vitamins. A symbiotic microbiota is normally characterized by a high diversity, and it can resist changes occurring during physiological stress, being able to stimulate the immune response [36]. Quality and amount of the intestinal microbiota could be modified by different factors such as diet, alcohol and smoking, impairing its ability to interface with the immune system and leading to an uncontrolled degree of inflammation [37,38].…”

Oralbiotica/Oralbiotics: The Impact of Oral Microbiota on Dental Health and Demineralization: A Systematic Review of the Literature

“…Metabolomics can also be added to these techniques, which tracks all metabolites produced by the microorganism involved in biological processes [ 9 , 10 , 11 ]. The human gastrointestinal tract, mouth, vagina, respiratory tract, and skin are colonized by microbial communities or microbiota [ 12 ].…”