Hypoxic conditions promote the expression of hypoxia-induced factors (HIF-1α) that lead to the expression of angiopoietin, matrix metalloproteinases (MMP’s) and VEGF, as well as other pro-angiogenic signals such as members of the fibroblast growth factor (FGF), that have been revealed to play a role in sustaining tumor angiogenesis when their expression is upregulated [39,40]. This evidence concerns the gene VEGFA and neoplasm.