银杏内酯B下调切除修复交叉互补基因1表达及增加耐药卵巢癌细胞对顺铂敏感性体外研究

目的:研究银杏叶提取物银杏内酯B(GB)增加耐顺铂卵巢癌细胞株(SKOV3/DDP-luc)对顺铂(CDDP)敏感性的作用及相关机制。方法:分别以DMSO及25μmol/L的GB处理SKOV3/DDP-luc细胞3、7及14d,溴化噻唑蓝(MTT)比色法检测细胞经不同浓度CDDP作用72h后的活性,并据此计算出各组细胞对CDDP的IC50;同时提取上述作用时间点各组细胞的总蛋白,Western Blot检测DNA损伤修复相关蛋白ERCC1的表达情况。结果:GB作用3、7、14d后,SKOV3/DDP-luc细胞对CDDP的IC50分别降为24.2(与对照组相比P=0.07)、18.2(与对照组相比P=0.001)、11.6μmol/L(与对照组相比P=0.0004);在上述处理过程中,肿瘤细胞中ERCC1的表达逐渐下降(P0.01)。结论:GB可显著增加耐药卵巢癌细胞株对CDDP的敏感性,这一作用通过下调肿瘤细胞中ERCC1蛋白的表达而实现,提示GB可能成为临床卵巢癌化疗过程中的一种辅助药物。

Research on Ginkgolide B increases Cisplatin sensitivity in ovarian cancer cell via down-regulation of excision repair cross-complementing 1(ERCC1) in vitro

Objective: To investigate the effects and mechanisms of ginkgolide B(GB),extract of Ginkgo biloba,on increasing the sensitivity of cisplatin-resistant ovarian cancer cell line(SKOV3/DDP-luc).Methods: SKOV3/DDP-luc cells were pretreated with 25μmol/L of GB for 3,7,and 14 days.Then,cells were exposed to different concentrations of CDDP and incubated for 72 hours.MTT assay was performed to determine the viability of the cells and the IC50 of CDDP was calculated according to the viability curve.Meanwhile,proteins were extracted from the cells treated by GB at different time point and the expression of ERCC1 was detected by Western Blot.Results: After cells were pretreated with GB for 3,7 and 14 days,IC50 of CDDP was significantly decreased to 24.2(P=0.07),18.2(P=0.001) and 11.6μmol/L(P=0.0004),respectively.The expression of ERCC1 protein in every group was decreased accordingly(P<0.01).Conclusion: GB can increase the drug sensitivity of CDDP-resistant human ovarian cancer cells significantly,which was implemented through down regulation of the expression of ERCC1.Our results suggested that GB could be a potential supplementary drug in ovarian cancer therapy.