Western blot with VEGF antibody and IHC with an antibody against CD31, a vascular marker, showed that overexpression of DEK promoted VEGF expression and tumor angiogenesis, and HIF-1α knockdown inhibited but not abolished DEK-mediated enhancement of VEGF expression and angiogenesis (Figure 7B, 7C). This evidence concerns the gene PECAM1 and neoplasm.