The oxygen-sensitive Hif-1α transcription factor is up-regulated in regions of tumor hypoxia and increases aerobic glycolysis by increasing the expression and activity of key enzymes in the glycolytic pathway, such as LDHA as well as monocarboxylate transporters (MCT1 and 4) responsible for the transport of pyruvate and lactate in and out of the cell [8,9]. The gene discussed is HIF1A; the disease is neoplasm.