膀胱癌MRP亚克隆的建立及其MDR表型

Establishment of MRP overexpression subline of bladder carcinoma and its MDR phenotype

目的 观察膀胱癌细胞多药耐受相关蛋白 (MRP)的表达情况及多药耐受 (MDR)表型。方法 将全长MRPcDNA转染膀胱癌EJ细胞 ,建立稳定表达MRP的亚克隆EJ/MRP ,用RT PCR、免疫组织化学方法检测了MRP和mdr1基因的表达 ,并检测了其对 11种化疗药物的敏感性。结果 和转染空载体的EJ/Vect细胞相比 ,EJ/MRP的MRPmRNA水平提高了 14.3倍 ,MRP表达部位主要位于细胞浆和细胞膜 ,但两种细胞均没有mdr1mRNA和P gp的表达。对Vp 16、VCR的耐受度超过 10倍 ,对DOX、HYD、THI、MMC和CYC的耐受度达 3～ 10倍。结论 EJ/MRP稳定高表达MRP ,无mdr1/P gp表达 ,具有典型的MDR表型 。

Objective To investigate MRP expression and multidrug resistance(MDR) phenotype of a bladder carcinoma subline transfected with the full length MRP cDNA. Methods After transfection, a stable MRP overexpressed subline named EJ/MRP was established. Gene expression of MRP and mdr1 were detected by using RT PCR and immunohistochemistry methods. Drug sensitivity testing of the EJ/MRP cells to 11 kinds of anti cancer agents was examined.Results Compared with EJ/Vect which was mock transfected, MRP mRNA level of EJ/MRP increased 14.3 fold and MRP expression was mainly located in cytosol and plasma membrane. The relative resistance(RR) to VP 16, vincristine increased more than 10 fold, and that to doxorubicin, hydroxycamptothecin, thiotepa, mitomycin and cyclophosphamide increased 3 to 10 fold. Conclusion Bladder carcinoma with stably over expressed MRP presents typical MDR phenotype but without mdr1/P gp expression. It provides a good model and positive control for the study of MRP mediated MDR.