胃癌SGC7901/DDP细胞microRNA的表达谱分析及其在耐药逆转中的作用

 目的：分析胃癌SGC7901/DDP细胞microRNA表达谱及其耐药特性，研究筛选出的microRNA-200c对SGC7901/DDP细胞耐药的影响。方法：采用MTT法检测细胞的药物敏感性；应用microRNA芯片进行表达谱分析；运用生物信息学对筛选出的microRNA进行靶点预测和生物学进程分析。采用实时荧光定量RT-PCR检测microRNA-200c的表达；采用细胞转染分析microRNA-200c对SGC7901/DDP细胞药物敏感性的影响。结果：SGC7901/DDP细胞对顺铂、阿霉素、5-氟脲嘧啶及紫杉醇的IC50均显著高于SGC7901细胞(P<0.05)。与SGC7901细胞相比，SGC7901/DDP细胞中表达上调和下调超过2倍的microRNA分别有5和14个。microRNA高低表达组预测的靶点均广泛参与信号传导、细胞周期、分化、凋亡、增殖等生物学进程。实时荧光定量RT-PCR分析证实microRNA-200c在SGC7901/DDP细胞中的表达显著降低(P<0.05)，microRNA-200c能够显著降低SGC7901/DDP细胞对顺铂、阿霉素、5-氟脲嘧啶及紫杉醇的IC50(P<0.05)。结论：SGC7901/DDP细胞的多药耐药特性可能与microRNA表达谱的改变有关，其耐药表型的逆转可能与microRNA-200c的表达有关。

Microarray analysis of microRNA expression profile and its role in reversing drug resistance in gastric cancer cell line SGC7901/DDP

Objective To analyze the microRNA expression profile and drug resistance characteristic and explore the roles of microRNA-200c on drug resistance in gastric cancer cell line SGC7901/DDP.Methods Drug sensitivity of SGC7901/DDP and SGC7901 cells were tested by means of MTT assay.microRNA array was used to analyze microRNA expression profile,and bioinformatics analysis was used to predict potential targets and biological functions of differentially expressed microRNAs.Real-time fluorescent quantitative RT-PCR was used to validate the result of microRNA-200c expression change from microRNA array analysis.And the effects of microRNA-200c on drug resistance were also analyzed in SGC7901/DDP cells by means of cell transfection.Results The IC50 of cisplatin,doxorubicin,5-fluorouracil and paclitaxel were significantly higher in SGC7901/DDP cells than that in SGC7901 cells(P<0.05).Compared with SGC7901 cells,5 microRNAs were upregulated more than 2-fold,and 14 microRNAs were downregulated more than 2-fold in SGC7901/DDP cells.The predicted targets in both downregulated and upregulated microRNA expression group were involved in the biological processes of signal transduction,cell cycle,cell differentiation,apoptosis,proliferation and etc.microRNA-200c was confirmed down expressed in SGC7901/DDP cells by real-time fluorescent quantitative RT-PCR.And SGC7901/DDP cells transfected with microRNA-200c precursor displayed significantly decreased IC50 of cisplatin,doxorubicin,5-fluorouracil and paclitaxel(P<0.05).Conclusions Changes of microRNA expression may be related to the multidrug-resistant in SGC7901/DDP cells,and its reversed drug resistance phenotype may be correlate with the microRNA-200c expression.