FasL基因转染对人乳腺癌MCF-7细胞药物敏感性的上调效应

The Up-Regulation of the Drug Sensitivity of Human Breast Cancer Cell Line MCF-7 by FasL Gene Transfer

目的:探讨FasL基因转染对肿瘤细胞化疗敏感性的调节效应,方法:LjpofectAMINE介导建立FasL基因修饰的乳腺癌细胞系MCF-7(?)FL,MTT法检测化疗药物对转染细胞的杀伤效应,半定量RT-PCR分析化疗药物作用前后转染细胞Fas mRNA表达水平变化,结果:经C418筛选,RT-PCR和免疫组化鉴定,建立FasL稳定表达MCF-7/FL,ADM在0.625～2.5μg′ml之间.MTX在3～6μg′ml.CDDP在1.25～10μg ml间对MCF-7FL的杀伤效应均明显高于MCF-7和转染空载体的MCF-7Vt而F(ab’)_2-APO-LMcAb可部分抑制这—增强效应,半定量RT-PCR显示上述化疗药物作用后MCF-7/FL Fas mRN水平表达显著增强,结论:外源FasL基因导入可上调肿瘤细胞对多种化疗药物的敏感性。

Objective: To investigate whether FasL expression by exogenous FasL gene transfer had regulatory effect on drug sensitivity of tumor cells. Methods: Exogenous Fasl, gene transfer was mediated by lipofectAMINE. The FasL expression was detected bv Immunohistochemistry and RT-PCR. The growth inhibition of cytotoxic drugs on tumor cells was measured by MTT assay. Fas mRNA expression was analyzed bv Semi-quantitative RT-PCR. Results: The eukaryotic expression vector, PcDNA3-FasL and PcDNA3 were successfully transteeted into MCF-7 cells. The transfectant cells was named as MCF-7/FL or MCF-7/Vt respectively. FasL was expressed on MCF-7/FL but not on MCF-7/Vt or MCF-7. The cytolysis ot MCF-7/FL induced by adriamycin at concentration of 0.625 ~ 2.5 μg/ml, cisplatin of 1 .25 ~ 10 μg/ml, or methotrexate of 3 ~ 6 μg/ml respectively were all significantly enhanced compared with the cytolysis of MCF-7. Blocking FasL by using F(ab' )2-anti APO-1 antibody markedly reduced this up-regulated cytolysis induced by these drugs The significant up-regulation of Fas mRNA on MCF-7/FL was observed by Semi-quantitative RT-PCR after these drugs treatment. Conclusion: These findings indicated that FasL expression by gene transfer had up-regulation effect on drug sensitivity of tumor cells, this effect was associated with enhanced Fas expression induced by cytotoxic drugs.