Liu Hai-feng, Zhang Feng-mei, Liu Bing-ci, Ye Meng, Jia Xiao-wei
National Institute of Occupation Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2011 May;29(5):330-3.
To study the roles of Ku80/p53 pathway in silica-induced cell cycle changes in human embryo lung fibroblasts (HELF).
Ku80 siRNA expression vectors were transfected into HELF by lipofectamine. Flow cytometry was used to detect the distributions of cell cycle and western blot assay was used to determine the expression level of Ku80, p53 and p21 proteins or the phosphorylation levels of p53-ser15 after cells were exposed to silica.
The expression levels of Ku80 protein increased in concentration-dependent and time-dependent manners after cells were exposed to silica. The proportion of G1 phases in H-NC cells (controls) decreased from 89.28% +/- 2.19% to 68.93% +/- 3.79% after exposure to silica, and the proportion of G1 phases in HELF cells (H-Ku80) decreased from 85.16% +/- 3.73% to 59.92% +/- 3.31% after exposure to silica (P<0.05). The expression levels of Ku80, p53 proteins or p21 proteins or phosphorylation level of p53-ser15 were obviously suppressed in H-Ku80, as compared with H-NC.
Ku80/p53 pathway plays a role in the cell cycle charges induced by silica in human embryo lung fibroblasts.
研究Ku80/p53信号通路在二氧化硅诱导人胚肺成纤维细胞（HELF）细胞周期变化中的作用。
采用脂质体法将Ku80 siRNA表达载体转染至HELF细胞。细胞暴露于二氧化硅后，采用流式细胞术检测细胞周期分布，采用蛋白质免疫印迹法检测Ku80、p53和p21蛋白的表达水平或p53-ser15的磷酸化水平。
细胞暴露于二氧化硅后，Ku80蛋白表达水平呈浓度和时间依赖性增加。H-NC细胞（对照组）暴露于二氧化硅后，G1期比例从89.28%±2.19%降至68.93%±3.79%；HELF细胞（H-Ku80）暴露于二氧化硅后，G1期比例从85.16%±3.73%降至59.92%±3.31%（P<0.05）。与H-NC相比，H-Ku80中Ku80、p53蛋白或p21蛋白的表达水平或p53-ser15的磷酸化水平明显受到抑制。
Ku80/p53信号通路在二氧化硅诱导人胚肺成纤维细胞的细胞周期变化中发挥作用。
