SLC2A1 and cancer: It is well known that HIF-1α increases the glycolytic activity of cancer cells, resulting in the overexpression of glycolytic key enzymes like hexokinases (HK) or lactate dehydrogenase (LDH-A), and glucose and lactate transporters such as the GLUT-1, GLUT-3, and MCT-4 [24,25].