HIF1A and hemangioma: HIF-1α is known to be a key regulator in hypoxia-induced angiogenesis, which is a major proangiogenic factor in many hypoxic solid tumors,[18] and also is associated with the growth of hemangiomas.[19] We found that curcumin significantly repressed the expression of HIF-1α, as well as VEGF, a key downstream effector of HIF-1α pathway in HemECs.