HIF-1 in tumour cells activates the transcription of genes for pro-angiogenic factors such as vascular endothelial growth factor (VEGF), PDGF-B (platelet-derived growth factor, type B), hepatocyte growth factor, epidermal growth factor, angiopoietin-2, or placental growth factor (Sacewicz et al. 2009). This evidence concerns the gene HIF1A and neoplasm.