Background and objective: The excision repair cross-complementing gene 1 (ERCC1), which is important in the repair of cisplatin-DNA adducts, was reported to be related to cisplatin resistance in tumor cells. The aim of this study is to investigate the changes of cisplatin sensitivity by silencing ERCC1 gene in lung cancer cell.
Methods: The small interfering RNA (siRNA) targeting ERCC1 gene was designed and synthesized, and transfected to lung cancer cell A549/DDP. The mRNA and protein expression levels of ERCC1 were evaluated by RT-PCR and Western blot. The changes of cisplatin sensitivity after RNA interference were examined by methyl thiazolyl assay.
Results: In A549/DDP cell, the mRNA and protein levels of ERCC1 were decreased and the sensitivity to cisplatin was increased from 12.49 μg/mL to 9.27 μg/mL after transfection.
Conclusions: The sensitivity to cisplatin of lung cancer cell A549/DDP could be enhanced by RNA interfering ERCC1 gene targeted code 346.
背景与目的: 核苷酸切除修复机制可修复顺铂(DDP)造成的DNA损伤，作为其中的关键酶之一，切除修复交叉互补基因1(excision repair cross-complementing gene 1, ERCC1)的表达可能与DDP耐药有关。本研究旨在探讨小干扰RNA沉默ERCC1基因表达对肺腺癌耐药细胞A549/DDP药物敏感性的影响。
方法: 将体外设计合成针对ERCC1的小分子RNA(siRNA)转染A549/DDP细胞，RT-PCR检测ERCC1 mRNA水平；Western blot检测ERCC1蛋白表达的变化；MTT检测RNA干扰后细胞药物敏感性改变。
结果: ERCC1 RNAi干扰后ERCC1 mRNA表达指数降低，明显低于对照组，干扰后ERCC1 mRNA表达抑制率为90.4%。转染ERCC1 siRNA降低了ERCC1蛋白的表达水平。MTT显示分别用2 μg/mL、4 μg/mL、8 μg/mL、16 μg/mL、32 μg/mL顺铂处理细胞48 h，转染ERCC1 siRNA细胞组较对照组敏感性明显增高，干扰前A549/DDP细胞IC50为12.49 μg/mL，干扰后A549/DDP细胞IC50下降为9.27 μg/mL。
结论: ERCC1 siRNA干扰可以降低ERCC1的表达水平，并可提高A549/DDP细胞对顺铂的敏感性。