Objective To explore the clinical significance of the differential expression of PTEN in glioma tissue.Methods The mRNA and protein expressions of PTEN were assayed by reverse transcription polymerase chain reaction(RT-PCR) and immunohistochemistry in 75 human brain glioma cases.Results The positive expression rate mRNA of PTEN differed significantly between brain glioma tissue and normal brain tissue(?2=22.66,P

OBJECTIVETo investigate the glycolytic phenotype of SHG44 human glioma cells under hypoxic conditions and the association between cell proliferation and apoptosis and the metabolic status.

METHODSAn in vitro hypoxic cell model was established in SHG44 cells using CoCl2. Real-time PCR and Western blotting were used to assess the expressions of hypoxia-inducible factor-1α (HIF-1α) and the enzymes involved in glycolysis including PDK1, PKM2, and LDHA. Intracellular ATP levels were measured by bioluminescence assay to assess the energy metabolic status of SHG44 cells. The viability and apoptosis of the cells were examined using MTT assay and flow cytometry, respectively.

RESULTSThe cells in hypoxic culture showed obviously increased expressions of HIF-1α, LDHA, PDK1, and PKM2 at both the mRNA and protein levels as compared to those in normal cell culture. Hypoxia of the cells also resulted in a lowered cell proliferative activity and an increased apoptosis rate with lowered intracellular ATP concentrations and elevated mitochondrial membrane potential.

CONCLUSIONHypoxia can induce a glycolytic phenotype of tumor cells. The sensitivity of tumor cells to hypoxia-induced cell death is directly correlated with their metabolic status.

Adenosine Triphosphate ; metabolism ; Apoptosis ; Carrier Proteins ; metabolism ; Cell Hypoxia ; Cell Line, Tumor ; Cell Proliferation ; Central Nervous System Neoplasms ; metabolism ; pathology ; Glioma ; metabolism ; pathology ; Glycolysis ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Membrane Potential, Mitochondrial ; Membrane Proteins ; metabolism ; Protein-Serine-Threonine Kinases ; metabolism ; Thyroid Hormones ; metabolism

Objective The aim of this study was to investigate the expression of cell cycle checkpoint kinase 1(Chk1)gene in glioblastoma cells( GBM) and its correlation with GBM cell proliferation,tumorigenic activity and prognosis. Methods The ex-pression of Chk1 in GBM cells was selected and analyzed by TCGA database and brain tumor molecular database( Rembrandt),and the level of Chk1 expression in GBM cells was detected by molecular biology techniques such as Western blot and Real-Time PCR. The expression of Chk1 was silenced by siRNA to investigate its effect on proliferation and colony-forming ability of GBM cells. The prognosis survival of GBM patients accompanying with Chk1 expression was analyzed by immunohistochemical staining and Rembrandt database. Results The results of TCGA database and Rembrandt showed that Chk1 gene was highly expressed in GBM tissues. West-ern blot and Real-Time PCR also showed that Chk1 gene was highly expressed in GBM cells. Lentiviral transfection siRNA-specific silencing of Chk1 significantly inhibited proliferation and colony-forming ability of U87 cells( P<0. 01 and P<0. 05). Prognostic survival analysis showed that GBM patients with low expression of Chk1 gene had a significantly better clinical outcome than those of GBM patients with high expression of Chk1 gene(P<0. 001). Conclusion Chk1 gene is overexpressed in GBM cells,up-regula-tion of Chk1 gene expression can promote the growth and proliferation of GBM cells,and Chk1 gene is associated with poor prognosis in GBM patients.