SMAD3 and renal fibrosis: Additionally, nintedanib suppressed PDGFRβ, FGFR1, FGFR2, and VEGFR2 phosphorylation and blocked the expressions of STAT3, NF-κB, and Smad3 to diminish macrophage infiltration, thereby ultimately exerting anti-renal fibrosis effects (Liu et al., 2017).