Sorcin表达受抑乳腺癌多药耐药细胞株MCF-7/A02对化疗药物敏感性的观察

Influence of knock-down of Sorcin expression to multidrug resistance of human breast cancer cell line MCF-7/A02

目的观察可溶性耐药相关钙结合蛋白基因(Sorcin)表达受抑乳腺癌多药耐药细胞株MCF-7/A02对化疗药物敏感性的影响,并探讨其机制。方法将MCF-7/A02细胞分为两组,观察组转染针对Sorcin基因的siRNA,对照组不转染。MTT法检测细胞对阿霉素(ADR)、依托泊苷(VP-16)、高三尖杉酯碱(HHT)、长春新碱(VCR)的敏感性,用流式细胞仪检测细胞对碱性蕊香红-123(Rho-123)的外排功能及VP16处理后的细胞凋亡率,Western blot法检测细胞中的Bcl-2、Bax蛋白。结果观察组ADR、VP-16、HHT、VCR的IC50分别为(19.92±1.29)(、31.47±2.36)(、4.19±0.27)(、2.96±0.23)μg/ml,对照组分别为(111.57±5.60)(、144.77±20.43)(、24.30±0.43)、(5.89±0.28)μg/ml,两组比较,P均<0.01。观察组细胞凋亡率为9.15%±0.25%,对照组为4.10%±0.12%,两组比较,P<0.01。观察组细胞内Rho-123的荧光强度为6.34±0.86,对照组为5.42±0.73,两组比较,P>0.05。观察组细胞中Bcl-2、Bax蛋白表达量为0.59±0.0321、.80±0.03,对照组分别为0.69±0.025、1.94±0.04,两组比较,P均<0.05。结论抑制Sorcin表达可显著增强MCF-7/A02细胞对化疗药物的敏感性;这种作用可能与其调节Bcl-2/Bax通路促进MCF-7/A02细胞凋亡有关。

Objective To study the effect of soluble resistance-related calcium-binding protein gene （Sorcin） on multidrug resistance （MDR） in MCF-7/A02 cells, and explore the correlative mechanisms. Methods MCF-7/A02 cells were divided into observe group （transfected with Sorcin gene siRNA） and control group （non-transfection）. The expression of Sorcin and proteins of Bcl-2, Bax were measured by western blot after siRNA transfection in MCF-7/A02 ceils. The sensitivity of cells to ADR, VP-16, HHT and VCR were measured by MTT assays. The accumulation of cytotoxic agents in cells and the apoptotic rate to VP-16 after siRNA transfection were detect by FACS. Results The ADR, VP-16, HHT, VCR IC5o of the observe group were （ 19.92 ± 1.29）, （31.47 ± 2.36 ）, （4.19 ± 0.27 ）, （2.96 ± 0.23 ） μg/ml, control group were （ 111.57 ± 5.60）, （ 144.77 ± 20.43 ）, （24.30 ± 0.43 ）, （ 5.89 ± 0.28 ） pLg/ml, all P 〈 0.01. Apoptosis rate of the treatment group was 9.15% ± 0.25% , control group was 4.10% ± 0.12%, P 〈 0.01. The cells MFI of observe group was 6.34 ± 0.86, control group was 5.42 ± 0.73, P 〉 0.05. Bcl-2/GAPDH, Bax/GAPDH light density ratio of the treatment group was 0.59 ± 0.03 and 1.80 ± 0.03, control group was 0.69 ± 0.20 and 1.94 ± 0.04, all P 〈 0.05. Conclusion The reduction of the expression of Sorcin leads to partly reversion of MDR phenotype in MCF-7/A02 cells, which is associated with the changes of Bcl-2 and Bax expression.