In addition, Mazzone et al. (2009) reported that a heterozygous deficiency of the oxygen-sensing prolyl hydroxylase domain protein2 (PHD2) reverts the abnormal tumor vasculature formed in the tumor-burdened mice to the mature and stable one, containing an orderly formed tight monolayer of endothelial cell known as “phalanx cells.” The sunitinib-treated endothelial cells in our model are reminiscent of the “phalanx cells” in the vascular walls. This evidence concerns the gene EGLN1 and neoplasm.