In addition, when PF occurs, downregulation of miR-29 expression increases the expression of TGF-β and CTGF and the phosphorylation of Smad3 and weakens the antifibrotic effects of the PI3K/AKT pathway and the Wnt/β-catenin signaling pathway, thereby promoting PF [104]. Here, SMAD3 is linked to pemphigus foliaceus.