Causal relationship between type II diabetes mellitus, metformin, insulin, gliclazide, and esophageal cancer—insights from two-sample Mendelian randomization study and meta-analysis

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Key findings

• A genetic predisposition to type II diabetes mellitus (T2DM) is associated with a reduced risk of esophageal cancer (EC).

• Metformin use is linked to a decreased prevalence of EC, while insulin and gliclazide show no significant association.

What is known and what is new?

• Existing knowledge: previous studies have produced mixed results regarding the relationship between T2DM and the risk of EC, with some suggesting potential links to specific medications.

• This study: utilizes a two-sample Mendelian randomization approach combined with meta-analysis to clarify the causal associations between T2DM, its treatments, and the risk of EC.

What is the implication, and what should change now?

• The findings suggest that metformin may offer protective benefits against EC, warranting further investigation into its mechanisms.

Publication: Lin Y, Lin J, Xu H, Hong Z, Kang M. Causal relationship between type II diabetes mellitus, metformin, insulin, gliclazide, and esophageal cancer—insights from two-sample Mendelian randomization study and meta-analysis. J Thorac Dis 2025;17(1):243-253. doi: 10.21037/jtd-24-1152