Effects of Ku86 knockdown on the radiosensitivity of Hela cells
He Ke,Qu Hu,Xu Linan,Niu Gang,Fei hui,Jiang Hongye,Liang Yanchun,Li Tingting,Yao Bing
Department of Obstetrics and Gynecology,First Affiliated Hospital of Sun Yat-sen University,Guangzhou 510080,China (He K,Niu G,Fei H,Jiang HY,Liang YCH);Reproductive Cente,Sixth Affiliated Hospital of Sun Yat-sen University,Guangzhou 510665,China (Qu H,Xu LN,Li TT,Yao B)
Abstract：Objective To study the effects of siRNA-mediated Ku86 knockdown on the radiosensitivity of human cervical carcinoma Hela cells. Methods Quantitative real-time PCR and Western blot were used to determine the expression of Ku86 gene in Hela cells exposed to X-ray radiation. siRNA was used for Ku86 knockdown. After transfection with si-NC or si-KU86, Hela cells were exposed to 0, 2, 4, 6, 8, and 10 Gy of X-ray. The CCK-8 kit, flow cytometry, and colony formation assay were used to evaluate cell proliferation, apoptosis, and changes in radiosensitivity after transfection, respectively. The expression of p53 and caspase-8 was evaluated to analyze the effect of Ku86 knockdown on radiation-induced apoptosis. Results After X-ray irradiation, both mRNA and protein expression of Ku86 was upregulated. Ku86 knockdown reduced cell proliferation and colony formation ability. The radiation sensitization enhancement ratio was 1.57. Ku86 knockdown also elevated the expression of p53 and caspase-8 and enhanced apoptosis. Conclusions siRNA-mediated Ku86 knockdown enhances the radiosensitivity of human cervical carcinoma Hela cells.
He Ke,Qu Hu,Xu Linan et al. Effects of Ku86 knockdown on the radiosensitivity of Hela cells[J]. Chinese Journal of Radiation Oncology, 2016, 25(9): 1008-1012.
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