TGFB1 and renal fibrosis: Gli2 drives cell cycle progression of myofibroblasts during renal fibrosis (Kramann et al, 2015), and its activity can be regulated either in a Hh ligand-dependent mechanism, or ligand-independent way via TGF-β/Smad signaling (Fig. 6H; Dennler et al, 2007; Meng et al, 2015).