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Microbiota and gastric cancer
Emilie Bessède1, Francis Mégraud1
1INSERM U1312 BRIC, University of Bordeaux, Campus of Carreire, 146 rue Leo Saignat, 33076 Bordeaux, France.
Seminars in Cancer Biology
|May 9, 2022
Summary
The stomach is not sterile; diverse microbiota exist, with Helicobacter pylori influencing them. Changes in gastric microbiota, beyond H. pylori, may drive gastric cancer development.
Area of Science:
- Microbiology
- Gastroenterology
- Oncology
Background:
- The discovery of Helicobacter pylori revolutionized our understanding of the stomach, previously considered sterile.
- Advances in molecular techniques like Next Generation Sequencing and metagenomics reveal a diverse gastric microbiota.
- H. pylori is a key factor in gastric cancer, but host and environmental factors also play a role.
Purpose of the Study:
- To explore the role of gastric microbiota, beyond H. pylori, in the development of gastric cancer.
- To investigate changes in microbial diversity and composition during gastric carcinogenesis.
- To understand the interplay between H. pylori, other microbes, and gastric disease progression.
Main Methods:
- Utilized Next Generation Sequencing and metagenomic approaches.
- Analyzed gastric microbiota composition across different stages of gastric premalignant and malignant lesions.
- Incorporated findings from mouse models to study microbial roles.
Main Results:
- Gastric carcinogenesis is associated with reduced microbial diversity.
- An increase in intestinal commensals with nitrosative functions and oral microbiota is observed in gastric lesions.
- The Epstein Barr Virus and mycobiota are implicated in a subset of gastric cancers.
Conclusions:
- Gastric microbiota, distinct from H. pylori, may contribute to the later stages of gastric carcinogenesis.
- Altered microbial communities, including shifts towards intestinal and oral commensals, are linked to gastric cancer development.
- Further research into viral and fungal components of the gastric microbiota is warranted.
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