In infantile hemangiomas, the possible mechanism of action of propranolol is vasoconstriction, decreased expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) genes through the down-regulation of the RAF (serine/threonine-protein kinase)-MAPK (mitogen-activated protein kinase) pathway (which explains the regression of the hemangioma), and the triggering of apoptosis of capillary endothelial cells [9]. This evidence concerns the gene WNK2 and capillary hemangioma.