For instance, studies have demonstrated that TGF-β/Smad3 promotes renal fibrosis by inducing the expression of miR-21, miR-433, and miR-192, which in turn suppressed PTEN, Smad7, ZEB1/2, and AZIN1, respectively [12–14, 16, 30, 41, 44]. Here, SMAD3 is linked to renal fibrosis.