Elevated levels of PDGF-A and -B expression have been detected in the skin, lung, and endothelial cells of SSc patients; furthermore, they are key players in liver fibrosis, and the data suggest that crosstalk between the TGF-β and PDGF pathways may regulate SSc chronic fibrosis [63]. This evidence concerns the gene TGFB1 and Hepatic fibrosis.