Related Experiment Video
Updated: May 29, 2026
07:50
Genome-Wide Analysis of DNA Methylation in Gastrointestinal Cancer
Published on: September 18, 2020
Gut microbiota-metabolite axis in gastric cancer: Genetic causality and Ruminococcus subgroup shifts
Jun Ji1, Xiaojing Feng2, Ying Sun3
1Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Cancer Genetics
|May 27, 2026
Summary
This study used Mendelian randomization to link gut microbes to gastric cancer risk, identifying 14 associated taxa. A specific pathway involving a microbe and sdLDL metabolite was found, suggesting potential microbiota-targeted prevention strategies for gastric cancer.
Area of Science:
- Microbiome research
- Genetics
- Gastroenterology
- Cancer research
Background:
- Observational studies suggest gut microbiota dysbiosis is linked to gastric cancer.
- Causal relevance and biological pathways remain unclear.
Purpose of the Study:
- To investigate the causal relationship between gut microbiota and gastric cancer risk using a Mendelian randomization framework.
- To identify specific microbial taxa associated with gastric cancer.
- To explore potential biological pathways mediating the effect.
Main Methods:
- Mendelian randomization (MR) analysis using gut microbiota and gastric cancer genome-wide association study (GWAS) summary statistics.
- Sensitivity analyses for horizontal pleiotropy, heterogeneity, and genetic co-localization.
- Mediation analysis to identify intermediate pathways.
- Pilot 16S rRNA sequencing.
Main Results:
- Identified 14 microbial taxa significantly associated with gastric cancer risk.
- Found no strong evidence of shared causal variants but supported overall causal inference across MR models.
- Identified a partial mediation pathway from a specific taxon (ebi-a-GCST90027718) to gastric cancer via the sdLDL metabolite (met-c-926).
- Pilot sequencing showed divergent shifts in Ruminococcus subgroups.
Conclusions:
- Establishes a genetically anchored link between host genetics, gut microbiota, and gastric cancer.
- Suggests specific microbial taxa and metabolic pathways may influence gastric cancer development.
- Provides insights for developing microbiota-targeted prevention strategies for gastric cancer.
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