c-erbB-2-siRNA对结肠癌HT-29细胞放射敏感性影响的研究

目的:观察单纯放射及放射联合应用siRNA对细胞增殖、细胞周期、凋亡和放射增敏性的影响.方法:分别用X射线单纯放射和放射合并转染c-erbB-2-siRNA质粒的结肠癌细胞(分别分为3组pGenesil-erbB-2实验组、阴性质粒对照组和转染试剂对照组),MTT法、平板克隆形成实验检测细胞增殖和放射敏感性,流式细胞仪检测细胞周期和凋亡.结果:6、8GyX射线照射组较0、2和4 Gy组的吸光度A值分别为0.314±0.035、0.117±0.009和0.721±0.044、0.608±0.018、0.584±0.041,6、8 Gy组显著低于0、2和4 Gy组,P=0.000 1；放射合并c-erbB-2-siRNA组在0、2、4、6和8 Gy照射组的吸光度A值分别为0.741±0.024、0.611±0.071、0.538±0.041、0.245±0.029和0.117±0.011,均显著低于其他两组,P=0.000 1.4、6、8组和0、2 Gy组G2/M期细胞数分别为12.19±0.41、15.02±0.38、18.56±0.94及6.50±0.43、5.26±0.71,前者显著高于后者,P=0.000 1;4 Gy X射线照射合并c-erbB-2-siRNA组、转染试剂对照组及阴性质粒对照组G0/G1期细胞数分别为79.93±0.79、69.34±1.17和69.40±0.84,实验组显著高于其他两组,P=0.000 1.0、2、4、6和8 GyX射线照射诱导HT-29细胞发生凋亡的无明显差别,P=0.065;4 Gy X射线照射合并c-erbB-2-siRNA组、阴性质粒对照组和转染试剂对照组的细胞凋亡率分别为19.21±3.54、6.82±0.74和7.56±0.35,实验组显著高于其他两组,P=0.000 1.放射合并c-erbB-2-siRNA组的放射增敏比为1.283和1.242,均＞1.结论:放射联合应用c-erbB-2-siRNA对结肠癌HT-29细胞具有抑制细胞增殖、诱导凋亡和放射增敏作用.

Influence of c-erbB-2-siRNA to the radiosensitivity of colon cancer cells

OBJECTIVE: To observe the influence of radiotherapy combined c-erbB-2-siRNA plasmid to cell growth,cell cycle,apoptosis and radiosensitivity of colon cancer cells.METHODS: The cells were divided in to three groups(c-erbB-2-siRNA-tranfected,scrambled siRNA construct transfected and no-transfected cells).Using MTT and Flat Cloning method detect the cell growth and radiosensitivity;using flow cytometric detect the cell cycle and the apoptosis rate.RESULTS: A value of 6,8 Gy X-ray irradiation group and 0,2,4 Gy group of spectrophotometry respectively were 0.314±0.035,0.117±0.009 and 0.721±0.044,0.608±0.018,0.584±0.041,and 6 and 8 Gy group were significantly lower than 0,2,4 Gy group(P=0.000 1);A value of radiation combined c-erbB-2-siRNA in 0,2,4,6,8 Gy group of spectrophotometry respectively were 0.741±0.024,0.611±0.071,0.538±0.041,0.245±0.029,0.117±0.011,which were significantly lower than the other two groups(P=0.000 1).In 4,6,8 Gy X-ray irradiation group and 0,2 Gy group G2/M cell cycle respectively were 12.19±0.41,15.02±0.38,18.56±0.94 and 6.50±0.43,5.26±0.71,the former G2/ M cell cycle were significantly higher than the latter(P=0.000 1);4 Gy X-ray irradiation combined c-erbB-2-siRNA group,scrambled siRNA construct transfected and no-transfected cells in G0/G1 cell cycle respectively were 79.93±0.79,69.34±1.17,69.40±0.84,The experimental group was significantly higher than the other two groups(P=0.000 1).The apoptosis rate of the radiotherapy with 0,2,4,6,8 Gy had No significantly difference(P=0.065);But the apoptosis rate of 4 Gy X-ray irradiation combined c-erbB-2-siRNA group,scrambled siRNA construct transfected and no-transfected cells were respectively 19.21±3.54,6.82±0.74,7.56±0.35,The experimental group was significantly higher than the other two groups(P=0.000 1).The radiosensitizer ratio in c-erbB-2 siRNA-tranfected combined radiotherapy group were 1.283 and 1.242,greater than 1.CONCLUSION: C-erbB-2 siRNA-tranfected combined radiotherapy can significantly inhibit the growth of colon cancer cells,obviously induced cells apoptosis,and most especially increase radiosensitivity.