β-Catenin overexpression in malignant glioma and its role in proliferation and apoptosis in glioblastma cells.

β-Catenin, a core component of Wnt/β-catenin signaling, has been shown to be a crucial factor in a broad range of tumors, while its role in glioma is not well understood. In this study, the expression of β-catenin in astrocytic glioma tissues with different grade and human normal cerebral tissues was examined using reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. We found a higher expression level of β-catenin in astrocytic glioma patients with high grade in comparison with the normal controls. Additionally, siRNA was transfected into human U251 glioblastoma cells by liposome after the design of siRNA was confirmed to effectively inhibit the expression of β-catenin by RT-PCR. Compared to the control siRNA group, siRNA-mediated knockdown of β-catenin in human U251 cells inhibited cell proliferation, resulted in cell apoptosis, and arrested cell cycle in G₀/G₁. Additionally, downregulation of β-catenin decreased the expression level of cyclin D1, c-Myc and c-jun. Taken together, these results indicate that overexpression of β-catenin may be an important contributing factor to glioma progression.