The mRNA expression level of HIF-1α was significantly elevated in glioma tissue compared with adjacent normal tissues (P < 0.01, Fig. 1A); HIF-1α mRNA expression was significantly elevated in U251, SHG-44, and U87 glioma cell lines when compared with normal brain cells (P < 0.01, Fig. 1B). The gene discussed is HIF1A; the disease is central nervous system cancer.