HK2 and clear cell renal carcinoma: ARNT was recently found upregulated in clear cell renal cell carcinoma: its expression was responsible for cell migration/invasion and, coherently with our data (Figure 6) also for the regulation of glycolytic enzymes like PFKFB3, (6−phosphofructo−2−kinase/fructose−2,6−bisphosphatase 3) and HK2 (hexokinase-2) (79).