SSc patients show an overexpression of pro-angiogenic factors, like the vascular endothelial growth factor (VEGF), ET-1, and adhesion molecules, together with elevated levels of anti-angiogenic factors, like angiostatin, C-X-C motif ligand (CXCL)-4 chemokine, and IL-4 cytokine [51,52,53]. Here, EDN1 is linked to systemic sclerosis.