Decreased expression of HIF-1 protein level affects in downregulating HIF-1 target genes including vascular endothelial growth factor (VEGF) which modulate tumor angiogenesis [153,155], glucose transporter 1 (GLUT1) that mediate glucose uptake [156], and alpha-enolase (ENO1) which is crucial for glucose metabolism acting as a key catalyzing enzyme in the glycolysis (Figure 3→XI) [157]. This evidence concerns the gene ENO1 and neoplasm.