胃癌耐药细胞系BGC-823/CDDP耐药机制初步研究

The Study of Drug Resistance Mechanism of Cisplatin-resistant BGC-823/CDDP Cell Line

目的:建立体外胃癌耐药细胞系BGC-823/CDDP模型,初步探讨对其耐药机制进行初步研究。方法:采用体外逐步增加顺铂药物浓度反复间歇诱导法,建立人胃癌顺铂耐药细胞系BGC-823/CDDP模型,并冻存3个月后应用四甲基偶氮唑盐(MTT)法检测其药物敏感性,免疫细胞化学法检测P-gp、p53、bcl-2、TOP-Ⅱ、GST-π蛋白在耐药细胞系BGC-823/CDDP的表达。结果:MTT法检测其药物敏感性表明,与亲代细胞BGC-823相比较,冻存后耐药细胞对CDDP的耐药倍数为11.17倍,对丝裂霉素C(MMC)、5-氟尿嘧啶(5-Fu)、阿霉素(ADM)均有不同程度的耐药性,但其耐药性无明显变化。与亲代细胞BGC-823相比较GST-π在BGC-823/CDDF中的表达明显增高;P-gp、p53、bcl-2在两者表达均为阴性,TOP-Ⅱ在两者表达无明显变化。检测表明GST-π与人胃癌顺铂多药耐药有关。结论:建立了体外稳定耐药的人胃癌顺铂多药耐药细胞系BGC-823/CDDP,其具有交叉耐药性;GST-π与人胃癌顺铂多药耐药有关。

Objective： To establish a cisplatin-resistant human gastric cancer cell BGC-823/CDDP in vitro, and study its drug-resistant mechanisms. Methods： By continuously exposing and gradually increasing the dose of cisplatin, a cisplatin-resistant human gastric cancer cell line BGC-823/CDDP was established and it was frozened for 3 months. The drug sensitivity was measured by methythiazol tetrazolium （MTT） assay, and P-Glycoprotein （ P-gp）, p53, B-cell lymphoma 2 （ bcl- 2 ）, Topoisomerase （ TOP- Ⅱ） and Glutathione S epoxide transferase（GST-π） protein were examined by immunocytochemical method. Results： By MTT assay, the resistance index of frozen BGC-823/CDDP cells to CDDP was 11.17 and it also showed cross-resistance to mitomycin C （MMC）, 5-fluorouracil （5-Fu） and adriamycin （ADM）. Compared to the parental BGC-823 cells, the expression of GST-π protein was significantly up-regulated in BGC-823/CDDP（ P 〈 0. 01 ）. The expressions of P-gp,p53,bcl-2 protein were negative in both two cell lines （P 〉 0. 05）. Conclusion： A stably resistant BGC- 823/CDDP cell line with cross drug resistance is established in our experiment, and GST- π is related to cisplatin resistance of huamn gastric cancer.