Related Experiment Video
Updated: May 10, 2026
05:19
Magnetic Resonance Imaging Assessment of Carcinogen-induced Murine Bladder Tumors
Published on: March 29, 2019
Genetically Predicted Gut Microbiota and Bladder Cancer Risk: A Mendelian Randomisation Analysis
Feiran Wei1, Meng Zhao2, Xiaohui Sun3
1Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, 210009 Nanjing, Jiangsu, China.
Archivos Espanoles De Urologia
|May 9, 2026
Summary
This study explored the gut microbiome
Area of Science:
- Microbiome research
- Cancer genomics
- Genetic epidemiology
Background:
- Gut microbiota (GM) influences cancer development via immune and metabolic pathways.
- Observational studies suggest a GM-bladder cancer (BC) link, but are prone to bias.
- Mendelian randomization (MR) offers a genetic approach to investigate the gut-bladder axis.
Purpose of the Study:
- To genetically assess the association between gut microbial composition and bladder cancer (BC) risk.
- To utilize a two-sample Mendelian randomization (MR) framework for robust causal inference.
- To explore potential genetic links within the gut-bladder axis.
Main Methods:
- Two-sample MR analysis using genetic instruments for 119 GM taxa from MiBioGen.
- Bladder cancer (BC) data sourced from the UK Biobank.
- Inverse variance weighted (IVW) method, MR-Egger, and weighted median for primary and sensitivity analyses.
Main Results:
- Nominal associations were observed between five GM taxa and BC risk.
- Higher abundance of *Oscillibacter* and *Oscillospira* showed a trend towards lower BC risk.
- *Lachnospiraceae* (FCS020 group) showed a trend towards increased BC risk.
- No associations remained significant after Bonferroni correction; sensitivity analyses indicated no significant heterogeneity or pleiotropy.
Conclusions:
- This MR study identified nominal genetic links between GM composition and BC risk.
- Findings require cautious interpretation due to lack of statistical significance after multiple testing correction.
- Further validation and mechanistic studies are needed to confirm the gut-bladder axis role in bladder cancer.
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