阿霉素和紫杉醇诱发的人乳腺癌耐药细胞株的比较研究

目的通过比较研究乳腺癌耐药细胞株的细胞生物学特性,探讨不同化疗药物诱发的多药耐药细胞模型的共性。方法以人乳腺癌细胞株MCF-7为亲本细胞,采用阿霉素(Adriamycin,Adr)及紫杉醇(Taxol,Tax)低浓度持续加量诱导法建立了多药耐药的人乳腺癌细胞株MCF-7Adr及MCF-7Tax。SRB法测定细胞生长曲线、半数致死浓度(IC50)、耐药指数(RF)和耐药谱;显微镜观察细胞形态,FCM分析细胞动力学周期,免疫组化检测细胞表型变化;Hoechst33342染色分析侧群细胞(side population,sp)比例。结果MCF-7Adr及MCF-7Tax细胞较MCF-7亲本细胞对相应药物的IC50提高500倍,撤药培养100 d后RF仍维持在150倍以上,并对多种化疗药物产生交叉耐药性;耐药细胞分化程度低于同步传代的亲本细胞,细胞倍增时间与亲本细胞接近,但S期细胞明显增加,G1期细胞减少,且随着撤药时间的延长,耐药细胞的增殖速度加快;耐药细胞P-gP、LRP和GSTπ的表达水平较亲本细胞有明显增加,ER阳性表达丢失;耐药细胞中SP细胞比例明显增高。结论MCF-7Adr和MCF-7Tax具有多药耐药细胞的基本生物学共性,两者均可作为研究MDR机制的耐药细胞模型。

Comparison research on MDRhuman breast canceRcell lines induced by AdRand Tax

Aim To investigate the commonness of the multi-drug resistant(MDR) model cell lines induced by different chemotherapeutics agents by comparing the cell biology properties of the MDR human breast cancer cell line MCF-7Adr and MCF-7Tax.Methods Two MDR breast cancer cell lines MCF-7Adr and MCF-7Tax were established respectively in vitro by gradually increasing the concentration of Adriamycin and Taxol from the parent cell line MCF-7.SRB assay was used to evaluate the rate of cell growth,determine the IC50 and RF,and analyze the drug resistant spectrum.Cellular morphology was observed by microscope.Cell cycle distribution and the variation of cellular phenotype were analyzed by FCM and immunocytochemistry,respectively.The proportion of side population subclone in the cells was analyzed by Hoechst33342.Results The IC50 of the cell line MCF-7Adr to Adr and that of MCF-7Tax to Tax were 500 times higher than those of parent cell MCF-7,and their drug resistant index were kept on over 150 times higher after being cultured in drug-free medium.There was cross resistance to other chemotherapeutics agents.The differentiation of drug resistant cell lines was lower than the parent cell line MCF-7 which was cultured simultaneously.The cell proliferation time is similar to that of the parent cell line MCF-7,but the proportion of the drug resistant cell lines in S phase increased significantly while those in G1 phase decreased.In addition,the longer time the drug being withdrawn in medium,the faster cells proliferated.The expression levels of P-gp,LRP and GSTπ on the drug resistant cell lines increased,but the ER was not observed in both MCF-7Adr and MCF-7Tax,and so did the PR in MCF-7Tax.Compared with the parent cell line MCF-7,the proportion of side population subclone in the drug resistant cell lines increased significantly.Conclusions There were common cell biology properties of MDR in both MCF-7Adr and MCF-7Tax,and they were all good MDR breast cancer cell model for researching the MDR mechanism.