FZD6 and pulmonary fibrosis: It had been reported that mesenchymal stem cell-derived extracellular vesicles suppressed the proliferation of fibroblast by downregulating FZD6 expression in fibroblasts via microRNA-29b-3p in idiopathic pulmonary fibrosis [53]; other investigators had shown that macrophage-derived exosomes attenuated the fibrosis in airway epithelial cells through delivery of anti-fibrotic miR-142-3p [50].