胰腺癌耐药细胞株SW1990/Fu产生获得性耐药机制的研究

Acquired multidrug resistance in pancreatic adenocarcinoma cell line SW1990/Fu

目的探讨胰腺癌耐药细胞株SW1990/Fu产生获得性耐药的可能机制。方法以体外诱导建立的人胰腺癌耐药株SW1990/Fu为模型,通过逆转录-多聚酶链反应(RT-PCR)和免疫细胞化学(ICC)方法测定耐药相关基因在SW1990/Fu产生获得性耐药前后的变化;罗丹明外排实验检测SW1990/Fu细胞膜上的P-gp泵功能。结果RT-PCR结果显示多药耐药基因1(MDR)和肺耐药相关蛋白基因(LRP)在SW1990/Fu中的表达率分别为0.97±0.23和0.95±0.34,而在SW1990中的表达率仅分别为0.67±0.19和0.53±0.16,两者差异有统计学意义(P<0.05);多药耐药相关基因(MRP)和谷胱甘肽-S-转移酶(GST-π)在2株细胞中的表达水平无明显变化。ICC与RT-PCR的结果一致。在罗丹明浓度为0.5mg/L时,只检测到(11.4±2.5)%的SW1990/Fu细胞内有荧光染科积蓄,在亲本细胞中罗丹明阳性细胞为(57.9±5.4)%,而在P-gp阴性的HL60细胞中,(99.5±3.3)%的细胞内存在罗丹明的积聚。当罗丹明浓度增加时,其在SW1990/Fu细胞内的积聚也明显增加。结论耐药基因MDR1和LRP表达增强可能是胰腺癌耐药细胞株SW1990/Fu产生获得性耐药的主要机制。

Objective To investigate the possible mechanism of acquired multidrug resistance in pancreatic adenocarcinoma cell line SW1990/Fu. Methods The expression of multidrug resistance gene （MDR）, multidrug resistance protein （MDP）, lung resistance protein （LRP）, and glutathione S-trans- ferase-Pi （GST-π） in mRNA and protein levels was detected by RT-PCR and immunocytochemistry in well established drug resistant pancreatic adenocarcinoma cell line SW1990/Fu respectively. FACS was performed to detect P-gp function in SW1990/Fu, SW1990 and HL60 cell lines. Results MDR1 and LRP/mRNA expression levels detected by RT-PCR were significantly increased in SW1990/Fu compared to its parental cell line, and their protein levels detected by ICC had the same trend as mRNA. In contrash no significant difference was revealed by RT-PCR and ICC in MRP and GST-πmRNA and their protein level between these two cell lines. The accumulation of Rhodamin123 in SW1990/Fu was significantlydecreased （11.4 ± 2.5）% in comparison with that in SW1990 （57.9 ± 5.4）% and HL60 （99.5 ± 3.3）%. Conclusion Drug resistant related genes MDR1 and LRP overexpression maybe contribute to acquired drug resistance.