论文部分内容阅读
目的:研究人鼻咽癌细胞系CNE-2Z亚克隆株F1、S1放射后DNA修复相关基因DNA pol β和Ku80的表达,探讨CNE-2Z存在放射敏感性异质性的可能机理。方法:裸鼠体内移植瘤实验观察F1、S1放射后的体内增殖能力,采用Western blot、免疫细胞化学和免疫组织化学方法检测放射后F1和S1 DNA修复相关蛋白(DNA pol β、Ku80)的表达,Feulgen染色法和图像分析方法检测放射后F1、S1裸鼠体内移植瘤的DNA倍体及细胞周期分布情况。结果:未照射前F1细胞DNA pol β和Ku80的表达高于S1;放射后S1细胞DNA pol β及Ku80表达上调的时间较F1早,上调辐度大于F1。鼻咽癌细胞系CNE-2Z确实存在放射敏感性的异质性,放射后S1体内增殖能力大于F1,较多细胞处于有利于DNA修复的G2/M期(P<0.01)。放射后F1、S1裸鼠移植瘤细胞和组织中,DNA pol β和Ku80蛋白表达差异无统计学意义(P>0.05)。结论:本实验进一步证实了鼻咽癌细胞系CNE-2Z确实存在放射敏感性的异质性,F1、S1放射敏感性的差异与两株细胞的DNA修复相关基因(DNA pol β、Ku80)的表达差异所致的DNA SSB、DSB修复的速度和忠实性有关。
OBJECTIVE: To study the expression of DNA repair genes related to DNA repair, pol β and Ku80, after radiotherapy of human nasopharyngeal carcinoma cell line CNE-2Z subclone F1 and S1, and to explore the possible mechanism of the existence of radiosensitivity heterogeneity of CNE-2Z. Methods: The in vivo proliferation of F1 and S1 cells after transplanted in nude mice were observed. The expression of DNA pol β (Ku80) in F1 and S1 after radiotherapy was detected by Western blot, immunocytochemistry and immunohistochemistry , Feulgen staining and image analysis were used to detect DNA ploidy and cell cycle distribution of transplanted tumor in F1 and S1 nude mice after radiotherapy. Results: The expression of DNA pol β and Ku80 in F1 cells before irradiation was higher than that in S1. The up-regulation of DNA pol β and Ku80 expression in S1 cells was earlier than that in F1 and the up-regulation spike was larger than F1. The nasopharyngeal carcinoma cell line CNE-2Z did have radiosensitivity heterogeneity. The proliferative capacity of S1 in vivo after radiotherapy was greater than that of F1, and more cells were in the G2 / M phase (P <0.01), which was in favor of DNA repair. There were no significant differences in the expression of DNA pol β and Ku80 protein in the transplanted tumor cells and tissues of F1 and S1 nude mice after radiotherapy (P> 0.05). CONCLUSIONS: This experiment further confirms the heterogeneity of radiosensitivity of nasopharyngeal carcinoma cell line CNE-2Z. Differences of radiosensitivity of F1 and S1 with DNA polβ, Ku80 of two cell lines The difference in expression of DNA SSB, DSB repair rate and loyalty.