Ligand-dependent EphB1 signaling suppresses glioma invasion and correlates with patient survival.

Background: Extensive evidence implicates the Eph receptor family of tyrosine kinases and its ligand, ephrin, in glioma invasion, but it remains incompletely understood how these receptors affect chemotactic behavior of glioma. We sought to identify the Eph family members that correlate with patients' survival and to reveal the function of Eph in glioma invasion.

Methods: Clinical relevance of EphB genes was confirmed in a clinically annotated expression data set of 195 brain biopsy specimens.

Glycogen synthase kinase 3β inhibition sensitizes human glioblastoma cells to temozolomide by affecting O6-methylguanine DNA methyltransferase promoter methylation via c-Myc signaling.

Glycogen synthase kinase 3β (GSK3β) is a serine/threonine protein kinase involved in human cancers including glioblastoma. We have previously demonstrated that GSK3β inhibition enhances temozolomide effect in glioma cells. In this report, we investigated the molecular mechanisms of sensitization of glioblastoma cells to temozolomide by GSK3β inhibition, focusing on O(6)-methylguanine DNA methyltransferase (MGMT) gene silencing.

Epithelioid glioblastoma changed to typical glioblastoma: the methylation status of MGMT promoter and 5-ALA fluorescence.

A 55-year-old man was admitted to our hospital complaining of left hemiparesis. Magnetic resonance imaging (MRI) showed a smooth ring-like enhanced cystic tumor in the right parietal lobe. He underwent gross total resection of the tumor under neuronavigation and 5-aminolevulinic acid (5-ALA) fluorescence guiding method.

The correlation between promoter methylation status and the expression level of O6-methylguanine-DNA methyltransferase in recurrent glioma.

Background: The DNA repair protein O(6)-methylguanine-DNA methyltransferase is a drug-resistant protein, which protects the tumors from chemotherapeutic alkylating agents, such as temozolomide. The methylation status of O(6)-methylguanine-DNA methyltransferase promoter has been shown to be a major predictive factor for clinical outcome in glioma patients when treated by alkylating agents. Thereby, there were many reports on O(6)-methylguanine-DNA methyltransferase promoter methylation and mRNA expression in primary glioma, in contrast, there were only a few studies in recurrent glioma.