外源MDR-1基因对小鼠肺腺癌细胞耐药性产生的影响及机理研究

An establishment of murine drug resistant cell line transfected with human MDR 1 gene

目的 了解MDR 1基因表达与肺癌细胞耐药性的关系。方法 用FUGENTM6转染试剂将MDR 1基因导入小鼠Lewis肺腺癌细胞株 ( 3LL) ,建立了耐药细胞株 ( 3LL MDR 1)。用MTT方法测定细胞耐药性并观察异搏定对耐药的逆转效应 ,MDR 1基因表达产物P gp采用免疫组化方法观察 ,应用流式细胞仪分析其对示踪剂罗丹明1 2 3的摄取与排泄。结果 建立了一株能稳定表达P gp和对长春生物碱类、鬼臼毒素类具有显著耐药性的细胞株。免疫组化证实耐药细胞高度表达P gp糖蛋白。异搏定能部分逆转该细胞株的耐药性 ,且效应随着剂量递增 ,流式细胞仪测定显示耐药细胞对示踪剂的排泄作用显著高于亲代细胞。结论 通过基因转染实验 ,证明MDR

Objective To investigate the relationship between MDR 1 gene expression and drug resistance in lung cancer cells. Methods The multidrug resistant cell line (3LL MDR 1) was established by transfecting human MDR 1 gene expressing vector into a murine Lewis lung cancer cell line (3LL). Drug resistance and the effect of valapamil (VLP) on the resistance were evaluated by MTT assay. The expression of MDR 1 gene product, P gp, was measured immunohistochemically. The influx and efflux of Rhodamine 123 was tested with flow cytometry. Results The MDR cell line expressing P gp was established, which exhibited a typical drug resistance to vincristine (VCR), vindesin (VDS), etoposide (VP 16), mitomycin (MMC), taxol and navelbine (NOR). Valapamil was able to reverse the resistance of the gene transfected cells and the reversion was dose dependent. Flow cytometric analysis showed that the resistant cells had much higher ability to export Rhodamine 123 than the parent cells did. The expression of P gp protein was visualized immunohistochemically. Conclusion The results indicate that drug resistance in lung cancer cells is closely related to the MDR 1 gene expression.