Pro-invasive effect of irradiation on human glioblastoma cell line U87 and its possible mechanism
Lyu Xiaojuan, Han Na, Zhang Mengxian, Dong Zhen
*Department of Tumor, Wuhan Centre Hospital, Wuhan 430024, China(Dong Zhen). Department of Neurosurgery, Tongji Hospital, Tongji Medical College,Huazhong University of Science and Technology, Wuhan 430030, China; Email:dongz@tjh.tjmu.edu.cn
Abstract：Objective To study the pro-invasive effect of irradiation on human glioblastoma cell line U87 and its possible mechanism. Methods Cultured U87 cells received different doses of irradiation (0, 2, and 4 Gy). The change in cellular invasiveness was measured using the real-time cell analyzer system. The activities of matrix metalloproteinase-2(MMP2) and matrix metalloproteinase-9(MMP9) in U87 cells were measured by gelatin zymography before and after irradiation. The content and distribution of intracellular β-catenin after irradiation were determined by immunohistochemistry. The mRNA levels of Wnt/β-catenin target genes were measured by real-time quantitative PCR. Results After irradiation, the invasiveness of U87 cells increased significantly (P<0.01), which was dose-dependent within a certain dose range;the activities of MMP2 and MMP9 in U87 cells increased significantly (P=0.031 for MMP2;P=0.004 for MMP9);the content of β-catenin in U87 cells increased significantly (P<0.01), with translocation from the cell membrane and adherens junctions to the nucleus;the mRNA levels of Wnt/β-catenin-related genes (FZD7 and TCF1) increased significantly (P<0.01), and the transcription of Wnt/β-catenin target genes, especially those related to migration and invasion such as MMP2, MMP7, MMP9, and CD44, was significantly enhanced (P<0.05). Conclusions Irradiation can promote the invasion of glioblastoma U87 cells, possibly by activating the Wnt/β-catenin pathway and enhancing the transcription of migration-and invasion-related genes.
Lyu Xiaojuan*,Han Na,Zhang Mengxian et al. Pro-invasive effect of irradiation on human glioblastoma cell line U87 and its possible mechanism[J]. Chinese Journal of Radiation Oncology, 2014, 23(3): 272-275.
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2014, Vol. 23 
