前列腺癌细胞Ku70表达水平对放射敏感性的影响  

Influence of radio sensitivity by the expression level of Ku70 in prostate cancer cells

作　　者：黄锦坤[1] 廖东江[1] 要国华[1] 戚德峰[1] 钟东亮[1] 雷鸣[1] 袁坚[1] 

机构地区：[1]广州医学院第一附属医院,广州510120

出　　处：《新医学》2013年第9期648-651,共4页Journal of New Medicine

基　　金：广东省科技计划项目(2008B080703046);广东省卫生厅科研基金(A2008262)

摘　　要：目的探讨前列腺癌PC3细胞Ku70表达水平变化及结合热休克对放射敏感性的影响。方法通过siRNA技术调节前列腺癌PC3细胞内源性Ku70蛋白表达,筛选转染后的PC3-Ku70(Ku70组)、PC3-β-actin(vector组)、PC3-Ku70-siRNA(RNAi组)、PC3-β-actin-siRNA(Scramble组)等4种稳定细胞株。采用免疫印迹和逆转录PCR方法检测其Ku70蛋白及mRNA表达水平,4组对数生长期细胞分别行Annexin V-FIC双染色及DAPI、TUNNEL染色检测细胞周期与凋亡情况,另取1株PC3-Ku70-siRNA细胞(热休克组)经42℃水浴30 min,转37℃细胞培养12 h再行射线照射,观察不同组间细胞存活率差异。结果免疫印迹和逆转录PCR显示RNAi组细胞Ku70表达水平明显下降,细胞周期与凋亡检测等检测显示伴随着Ku70表达降低,存活细胞减少,凋亡细胞增多,5组细胞随γ射线照射剂量的增加,细胞存活率下降,其中RNAi组的细胞存活率均低于对照组和Ku70组,5组比较差异有统计学意义(F=21.72,P<0.001)。PC3-Ku70-siRNA细胞经热休克处理后再行射线照射,其存活率明显低于未经热休克处理细胞株。结论抑制前列腺癌细胞中Ku70蛋白表达水平,结合热休克,可明显提高肿瘤组织对放射治疗的敏感性,这可能是一个较为理想的综合治疗前列腺癌的方法。Objective To investigate the effect of radio sensitivity in prostate cancer cell by the expression level of Ku70 and heat shock condition. Methods To regulate endogenous Ku70 protein expression in prostate cancer cells by siRNA technology andScreentransfected four kinds of stable cell lines： PC3-Ku70 （ Ku70 group）, PC3-13-actin （ vector group）, PC3-Ku70-siRNA （ RNAi group）, PC3-13-actin-siRNA （ Scramble group）. Western blot and RT-PCR method were taken to detect the Ku70 protein and mRNA expression levels. The 4 groups cells in logarithmic growth phase were performed by Annexin V-FIC double staining and DAPI, TUNNEL staining to assess the situation of the cell cycle and apoptosis. A group of PC3-Ku70-siRNA cells were treated at 42℃ for 30 min and cultured at 37℃ for 12 hours before irradiation to investigate differences in cell survival. Results Transfected PC3 cells by pBaBb-puro-Ku70, pSUPERretro-puro-Ku70, stably transfected clones were gained after selection. Western Blot and RT-PCR analysis showed that Ku70 protein expression levels were significantly regulated. , The surviving cells decreased and apoptotic cells increased with the down regulation of KuT0. The survival rate of five groups significantly decreased with increasing doses of ~/- ray irradiation, in which the RNAi group is lower than control and Ku70 group. The survival rate of PC3-Ku70- siRNA cell is significantly lower after γ-ray irradiation than before. Conclusions By inhibiting the Ku70 protein expression level in prostate cancer ceils, combined with the heat shock, can significantly improve the sensitivity of tumor tissue to radiation therapy, which may be an ideal method for the comprehensive treatment of prostate cancer.

关 键 词：前列腺癌 KU70 放射治疗 热休克 

分 类 号：R737.25[医药卫生—肿瘤]