In tumour ECs, VEGF-A and PFKFB3 play a major role in enhancing EC metabolism since inhibition of Prostaglandin endoperoxide synthase 2, also known as cyclooxygenase-2 (COX-2) decreases the expression of VEGF-A and PFKFB3 and reduces the glycolysis rate to the level of normal ECs [157]. This evidence concerns the gene PTGS2 and neoplasm.