Gut microbiota and oral cavity cancer: a two-sample bidirectional Mendelian randomization study.

UNLABELLED

This study employs a two-sample bidirectional Mendelian randomization (MR) approach to systematically evaluate the causal relationship between gut microbiota and oral cavity cancer (OCC).

OBJECTIVE

To address the challenge in establishing the causal relationship between gut microbiota and OCC, we applied a systematic MR analysis.

METHODS

Utilizing GWAS data from the MiBioGen consortium (18,340 individuals) and UK Biobank (n = 264,137), we selected instrumental variables and employed MR-Egger, weighted median, IVW, and weighted mode analyses. Heterogeneity and pleiotropy were assessed using Cochran's Q test and MR-Egger intercept test.

RESULTS

Our findings indicate, at the order level, (OR = 0.9990, 95% CI = 0.9980-1.0000, = ), (OR = 1.0009, 95% CI = 1.0001-1.0018, = ), and (OR = 0.9979, 95% CI = 0.9962-0.9995, = ) exhibit causality on OCC in the Weighted median, IVW, and MR-Egger analyses, respectively. At the family level, (OR = 1.0012, 95% CI = 1.0004-1.0019, = ) and (OR = 0.9970, 95% CI = 0.9948-0.9992, = ) show causality on OCC in IVW and MR-Egger analyses. At the genus level, (IVW, OR = 0.9987, 95% CI = 0.9980-0.9995, = ; MR-Egger, OR = 0.9978, 95% CI = 0.9962-0.9995, = ), (IVW, OR = 1.0008, 95% CI = 1.0001-1.0015, = ), (IVW, OR = 0.9995, 95% CI = 0.9990-1.0000, = ), group (IVW, OR = 1.0005, 95% CI = 1.0000-1.0009, = ), and (IVW, OR = 0.9994, 95% CI = 0.9989-0.9999, = ) are implicated in causing OCC in related analyses.

CONCLUSION

Our study identifies order, family, genus, and group as causally increasing OCC risk. In contrast, order, order, family, genus, genus, and genus are causally associated with a decreased OCC risk. However, further investigations are essential to delineate an optimal gut microbiota composition and unravel the underlying mechanisms of specific bacterial taxa in OCC pathophysiology.