CNE、SPC-A1和MCF-7人类肿瘤细胞Ku80基因同源性研究

Study on the Homology of Ku80 Gene in CNE,SPC-A1 and MCF-7 Cell Lines

目的 :研究人鼻咽鳞癌 (CNE)、肺腺癌 (SPC A1)和乳腺腺癌 (MCF 7)细胞Ku80基因功能区的保守性 ,探讨该基因突变与肿瘤放射和化学治疗疗效的关系。方法 :采用聚合酶链式反应和克隆技术测定 3种肿瘤细胞内与DNA损伤修复有关的Ku80基因序列 ,分析他们的功能区保守性变化 ,模拟和比较突变产物亲疏水性差异。结果 :人CNE、SPC A1和MCF 7肿瘤细胞Ku80基因同源性分别为99 95 %、99 5 %和 99 7% ,包括碱基转换和颠换突变。部分突变碱基导致产物氨基酸替代并影响他们的亲疏水结构。SPC A1细胞发生 15 0aaIle→Val、4 70aaAsp→Gly、5 5 3aaPhe→Ile替代和 5 70aaGln→ 0缺失 ;MCF 7细胞发生 2 0 9aaLys→Glu、2 31aaLeu→Arg和 2 97aa→Ser替代 ;而CNE细胞功能区高度保守。结论 :SPC A1和MCF 7细胞Ku80p功能区存在氨基酸替代 ,影响其结构和活性变化 。

objective To investigate the homology of Ku80 gene in CNE, SPC A1and MCF 7 cell lines and discuss the relationship between mutations of this gene and the result of radiotherapy and chemotherapy for tumor cells.Methods Polymerase chain response and cloning and sequencing technique were used to determine the sequence of Ku80 gene related with repair of DNA lesions in tumor cells,then their conservative changes, modulated and compared changes of the hydrophicity hydrophobicity of that gene productions were analyzed.Results In CNE,SPC A1and MCF 7 cell lines,the homology of Ku80 gene were 99 95%,99 5% and 99 7%,respectively,including transversion and transition,parts of which leading to alter amino acid with others and change the hydrophicity hydrophobicity of these products.Mutations in SPC A1 cell resulted in 150aa Ile→Val,470aa Asp→Gly,553aa Phe→Ile alterations and 570aa Gln→0 deletion and in MCF 7 cell,209aa Lys→Glu,231aa Leu→Arg and 297aa→Ser alterations,but this production in CNE cell was high conservation.Conclusions The conservations of encoding regions of Ku80 gene in SPC A1 and MCF 7 cell lines are lower than that in CNE cell line.Therefore,mutations may enhance both activity of reproductions and ability of repairing double strand breaks,and this is related to the outcome of radiotherapy and chemotherapy for human tumor. China J Cancer Prev Treat,2003,10(3):266-269