Fig. 1From: Genetic effect of metformin use on risk of cancers: evidence from Mendelian randomization analysisOverview of the study design. A We firstly applied two-sample MR analyses to figure out the genetic effect of metformin use on 26 prevalent cancers with five robust methods. B Two-step MR analysis and MVMR were further conducted to figure out the potential mediator who mediate the protective genetic effect of metformin on HER-positive breast cancerBack to article page