VEGF has been shown to inhibit renal fibrosis and EMT, which may be related to VEGF-blocking, TGF-β-induced Smad3 phosphorylation and upregulating Smad7 expression.32 In pulmonary fibrosis studies, the function of VEGF is controversial; some authors believe that VEGF can promote revascularization and accelerate pulmonary fibrosis,33 while others believe that VEGF can maintain the normal function of tissue structure to resist pulmonary fibrosis. This evidence concerns the gene SMAD7 and renal fibrosis.