In in vitro studies SSc dermal fibroblasts seem to be activated by IL-6 in autocrine/paracrine manners [11, 13], and the activation of endothelial IL-6/STAT3 axis induces proliferation, migration, vascular instability, and endothelial-to-mesenchymal transition [14], all of which are characteristically seen in SSc endothelial cells [10]. Here, STAT3 is linked to systemic sclerosis.