薯蓣皂苷下调ABCC1表达对人肝癌细胞HepG2/ADM耐药的影响

目的:探究薯蓣皂苷对人肝癌细胞HepG2/多柔比星(ADM)耐药性的影响及其可能的作用机制。方法:采用含0,10,20,30,40,50μmol·L^-1薯蓣皂苷的培养液培养HepG2、HepG2/ADM细胞,CCK法检测细胞增殖抑制率;MTT检测薯蓣皂苷对HepG2/ADM细胞、HepG2细胞半抑制浓度(IC50)值的影响;流式细胞术检测HepG2、HepG2/ADM细胞摄取ADM的能力。薯蓣皂苷联合ABCC1抑制剂处理HepG2/ADM细胞,MTT检测细胞IC50值变化;流式细胞术检测细胞摄取ADM的能力、细胞凋亡情况,免疫印迹法检测细胞人多药耐药相关蛋白1(ABCC1)、半胱天冬酶(caspase-3)、B淋巴细胞瘤-2(bcl-2)、Bcl-2相关X蛋白(Bax)蛋白表达情况。结果:HepG2/ADM细胞中ABCC1蛋白表达显著高于HepG2细胞(P<0.05)。薯蓣皂苷0~30μmol·L^-1对HepG2/ADM细胞、HepG2细胞毒性小。随着薯蓣皂苷处理浓度的升高,HepG2/ADM细胞IC50值均降低,摄取ADM量明显升高,具有剂量依赖性(P<0.05)。薯蓣皂苷联合ABCC1抑制剂处理HepG2/ADM细胞后能够进一步降低细胞IC50,提高细胞ADM摄取量,加速细胞凋亡,上调caspase-3、Bax蛋白表达,下调ABCC1、bcl-2蛋白表达(P<0.05)。结论:薯蓣皂苷能够逆转HepG2/ADM细胞耐药性,逆转效果与作用剂量相关,其机制可能与下调ABCC1表达,诱导细胞凋亡有关。

Effect of Diosgenin on Drug Resistance of Human Hepatocellular Carcinoma HepG2/ADM Cells by Down-regulating ABCC1 Expression

Objective:To investigate the effects of diosgenin on drug resistance of human hepatocellular carcinoma cell line HepG2/adriamycin(ADM),and to explore its possible mechanism.Methods:HepG2 and HepG2/ADM cells were cultured in the culture medium respectively containing 0,10,20,30,40 and 50μmol·L^-1 diosgenin.The inhibition rate of cell proliferation was detected by CCK method,the effects of diosgenin on 50%inhibiting concentration(IC50)values of HepG2/ADM cells and HepG2 cells were detected by MTT,and the abilities of HepG2 and HepG2/ADM cells to absorb ADM were detected by flow cytometry.HepG2/ADM cells were treated with diosgenin combined with ABCC1 inhibitor.The change of IC50 value was detected by MTT,the abilities of ADM uptake and the apoptosis of cells were detected by flow cytometry,and the expressions of multidrug resistance-associated protein1(ABCC1),caspase-3,Bcl-2 and Bcl-2 associated X protein(Bax)proteins were detected by Western blot.Results:The expression of ABCC1 protein in HepG2/ADM cells was significantly higher than that in HepG2 cells(P<0.05).Diosgenin at 0-30μmol·L^-1 had little cytotoxicity to HepG2/ADM cells and HepG2 cells.With the increase of diosgenin concentration,the IC50 values of HepG2/ADM cells decreased,and the ADM uptake increased,which were in dose-dependent manners(P<0.05).Diosgenin combined with ABCC1 inhibitor could further reduce IC50,increase ADM uptake,accelerate cell apoptosis,up-regulate caspase-3 and Bax protein expressions,and down-regulate ABCC1 and bcl-2 protein expressions in HepG2/ADM cells(P<0.05).Conclusion:Diosgenin can reverse the drug resistance of HepG2/ADM cells,and the reversal effect depends on the dosage.The mechanism may be related to the downregulation of ABCC1 expression and the induction of apoptosis.