SFRP5逆转白血病多药耐药性的研究

SFRP5 reversal multidrug resistance in leukemia KG1a cells

目的:研究分泌型卷曲相关蛋白5(secreted frizzled related protein 5,SFRP5)对P-糖蛋白(P-glycoprotein,P-gp)介导的白血病多药耐药性的作用。方法:采用转基因方法构建过表达SFRP5的KG1a/SFRP5细胞,real-time PCR检测MDR1 mRNA表达,Western blot检测细胞P-gp表达。免疫荧光显微镜观察细胞膜表面P-gp表达。流式细胞仪检测细胞内药物浓度。MTT方法检测细胞耐药性。结果:与KG1a细胞及表达绿色荧光蛋白的KG1a/eGFP细胞相比,KG1a/SFRP5细胞中MDR1 mRNA水平显著下降(P<0.01),总P-gp表达水平亦被下调,细胞膜表面P-gp荧光强度减弱,细胞内的罗丹明浓度显著升高(P<0.01),对ADR的IC50显著降低(P<0.01),细胞耐药性下降。结论:SFRP5蛋白表达可以下调MDR1转录及P-gp表达,增加细胞内药物浓度,逆转白血病多药耐药。

Objective： To investigate the effect of secreted frizzled-related protein 5 （SFRP5） on leukemic multidrug resistance. Methods： Transgenic methods were used to culture KGla cells expressing SFRP5 and enhanced green fluorescent protein （control）. mdrl mRNA expression in KGla, KGla/eGFP, and KGla/SFRP5 groups were detected by real-time polymerase chain reaction. P-glycoprotein （P-gp） expression was detected by Western blot analysis. P-gp expression on the cell surface was observed by immunofluorescence. In- tracellular drug concentration was detected by flow cytometry. Drug resistance was detected by MTT assay. Results： The KG 1 aJSFRP5 cell, a KGla cell expressing SFRP5, and the KGla/eGFP cell, a KGla cell expressing eGFP, were successfully constructed. The multidrug resistance protein 1 （mdrl） mRNA level in KGlaJSFRP5 cells was significantly decreased （P〈0.01）. P-gp expression in KGla/SFRP5 cells was also downregulated. Fluorescence intensity of P-gp on the KGla/SFRP5 cell surface was reduced. Rhodamine concentration in KGlaJ SFRP5 cell was significantly increased （P〈0.01）. ICs0 of KGlaJSFRP5 cell to Adriamycin was decreased as determined by the MTT method. Conclusion： SFRP5 expression in KGla cells can downregulate MDR1 transcription and P-gp expression, increase intracellular drug concentration, and reverse multidrug resistance.