Mediators such as platelet-derived growth factor (PDGF), vascular-endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are currently individually or collectively investigated as potential therapeutic targets for diseases such as cancers, pulmonary hypertension or idiopathic pulmonary fibrosis. The gene discussed is VEGFA; the disease is pulmonary arterial hypertension.