SMAD2 is a critical intracellular signal transduction mediator and transcription factor, which mediates TGF-β family signal transduction.22 SMAD2 can act as an oncogenic driver in human tumorigenesis.23-25 For example, circ_0001829 aggravates GC development by targeting the miR-155-5p/SMAD2 axis.26 We find that miR-429 suppresses GC progression by reducing SMAD2 expression. This evidence concerns the gene SMAD2 and gastric cancer.