Recently, the study in hepatocellular carcinoma (HCC) demonstrated that the fluorine-18 fluorodeoxyglucose (FDG) uptake level is positively correlated with HIF-1α expression and the expression of HIF-1α showed stronger positive relation with glucose transporter 4 (GLUT4) expression, compared with GLUT2 and GLUT3 [37]. The gene discussed is SLC2A4; the disease is hepatocellular carcinoma.