CA9 and neoplasm: The enhanced rates of glycolysis and glucose uptake in tumours are maintained by several adaptive mechanisms, including adaptation to hypoxia conditions [17-19], in which HIF-1α (Hypoxia inducible factor 1-α) is a key player by regulating several metabolism related proteins like the glucose transporter 1 (GLUT1), carbonic anhydrase 9 (CAIX) and MCTs [17, 20, 21].