Since antiangiogenic agents such as sorafenib can transiently prune the immature newly formed microvessels while sparing the relatively efficient vessels [46], our data implicate that upregulation of HIF2α expression and downregulation of VEGFA expression in A549shHTATIP2 tumors result in reduced tumor neovascularization but improved functional vascular properties. This evidence concerns the gene EPAS1 and neoplasm.