CTR1和ATP7B在人肺腺癌细胞A549的表达及其与顺铂耐药的关系

Resistance to cisplatin is mediated by synergistic action of CTR1 and ATP7B in A549 cell line in vitro

目的探讨人肺腺癌细胞株A549和肺腺癌顺铂耐药细胞株A549/DDP对顺铂的耐药机制。方法利用噻唑蓝法检测顺铂对A549/DDP及其亲代细胞株的细胞毒作用和生长曲线的影响,探讨A549/DDP细胞株凋亡敏感性的变化规律。采用Western blot检测该细胞株铜离子转运蛋白1(CTR1)、铜离子转运磷酸化ATP酶(ATP7B)及聚腺苷二磷酸-核糖聚合酶(PARP)剪切蛋白表达,分析A549细胞对顺铂耐药与CTR1、ATP7B及PARP剪切蛋白表达量的相关性。结果 A549/DDP较其亲代细胞株对顺铂引起的细胞毒性和凋亡敏感性下降;较其亲代细胞株A549/DDP中ATP7B表达增加,CTR1表达降低。结论人肺腺癌细胞株A549对顺铂耐药的产生与细胞凋亡敏感性降低有关,且细胞内ATP7B表达增加,CTR1表达降低,或可作为细胞对顺铂的增敏靶点。

Objective To study the mechanisms of cisplatin resistance of human lung adenocarcinoma cell lines A549 and A549/DDP. Methods Human lung adenocarcinoma A549 cells and a cisplatin-resistant derivative A549/DDP were treated with varying concentrations of cisplatin. The changes in cell growth,cytotoxicity and apoptosis were explored. Western blot was used to determine the expression of copper transporter 1（CTR1）, copper transporting phosphorylated ATPase（ATP7B） and poly-ADP-ribose polymerase（PARP）. The correlations of cisplatin resistance with CTR1, ATP7 B and PARP were analyzed. Results Compared to the A549 cells, the A549/DDP cells were less sensitive to cisplatin-induced cytotoxicity and apoptosis. ATP7 B expression increased but CTR1 expression decreased in the A549/DDP cells compared to the A 549 cells. Conclusions Our results demonstrate that reduced expression of the copper influx transporter CTR1 and overexpression of the copper efflux transporter ATP7 B are responsible for the resistance of A549/DDP cells to cisplatin. These results indicate well that the expression of ATP7 B and CTR1 may provide markers for chemoresistance and chemosensitivity, respectively, to cisplatin-based chemotherapy.