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shRNA沉默Sp1对胶质瘤细胞放射敏感性的影响
王琦琦1, 曾家豫1, 李强2, 刘雄雄2
1西北师范大学生命科学学院,兰州 730000; 2中科院近代物理研究所,兰州 730000
Effect of shRNA silencing of Sp1on radiosensitivity of glioma cells
Wang Qiqi1, Zeng Jiayu1, Li Qiang2, Liu Xiongxiong21
1 College of Life Science, Northwest Normal University, Lanzhou 730000, China; 2 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
Abstract:Objective To evaluate the effect of down-regulation of Sp1 expression on the radiosensitivity of glioma cells. Methods The oligonucleotide sequence encoding shRNA was designed and synthesized, and cloned into LV3 (H1/GFP & Puro) vector to construct the recombinant. U251 and U87 cells were infected with recombinant lentivirus, then the stably-transfected cell lines were obtained by puromycin screening. The expression levels of Sp1 mRNA and protein were detected by RT-PCR and Western blot. Cell survival was detected by clonal survival assay, cell cycle was determined by flow cytometry, and DNA damage was measured by immunofluorescence assay, respectively. Results At 72 h after infection, high expression of Sp1 lentiviral vector was observed in two cell lines under fluorescence microscope. RT-PCR and Western blot confirmed that the expression levels of Sp1 mRNA and protein were significantly down-regulated in both transfected cells (both P<0.01) and the silencing rates of Sp1 were above 90%. The sensitization enhancement ratio (SER) of shRNA-U251 and shRNA-U87 cells at 10% cell survival level were 1.39 and 1.18, respectively. After irradiation, the G2/M phase ratio and the number of γ-H2AX foci in two Sp1 knockout groups were significantly increased. Conclusions hRNA silencing of Sp1 increases the G2/M phase arrest induced by X-ray, aggravates the degree of DNA double-strand breaks, and improves the radiosensitivity of glioma cells.
Wang Qiqi,Zeng Jiayu,Li Qiang et al. Effect of shRNA silencing of Sp1on radiosensitivity of glioma cells[J]. Chinese Journal of Radiation Oncology, 2022, 31(7): 638-642.
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