miR-93通过靶定PTEN基因增加肝癌细胞对奥沙利铂的耐药性

MiR-93 Renders the Drug Resistance of Hepatoma Cells to Oxaliplatin through Targeting PTEN

微小RNA(miRNA)参与了肿瘤的耐药过程.本研究通过建立对奥沙利铂(oxaliplatin,Oxa)耐药的肝癌细胞系BEL-7402/Oxa和Hep-3B/Oxa,利用miRNA芯片结合实时荧光定量PCR的方法,筛选得到数个参与肝癌细胞对奥沙利铂耐药的miRNA分子,其中miR-93表达增加最为明显.MTT实验发现,增加肝癌细胞株中miR-93的表达可以增强其对奥沙利铂的耐药性.进一步结合生物信息学、荧光报告载体及免疫印迹实验,证实miR-93通过靶定抑癌基因PTEN增加肝癌细胞对奥沙利铂的耐药性.总之,肝癌耐药细胞系的建立及其miRNA差异表达谱的分析,以及miRNA分子对肝癌细胞发生奥沙利铂耐药的具体作用及其分子机制的研究,不仅有助于理解肝癌细胞发生耐药的分子机制,而且为探索克服肝癌对奥沙利铂耐药性的有效途径提供可靠依据.

microRNAs （miRNAs） are involved in the resistance of cancer cells to chemotherapeutic drugs. Here, we established two oxaliplatin （Oxa） resistant human hepatoma cell lines （BEL-7402/Oxa and Hep-3B/Oxa） and analyzed the dysregulated miRNA expression profile in the oxaliplatin-resistant cells in comparison to their parent cells by miRNA microarrays and real-time quantitative RT-PCR. And miR-93 was the most remarkably upregulated miRNA. Thus, we further investigated the role of miR-93 and found that increased expression level of miR-93 can significantly enhance the resistance of hepatoma cells to Oxa by MTT assays. Moreover,the tumor suppressor PTEN was found to be targeted directly by miR-93 through bioinformatics and EGFP reporter assays. Meanwhile, increased miR-93 can negatively regulate the expression level of PTEN protein. In summary, the establishment of the drug-resistant cell lines, the differential expression profile of drug-resistant and drug-sensitive ceils and the detail function and mechanism of individual miRNA in the role of hepatoma to Oxa will not only help us to understand the molecular mechanism of drug resistance, but also give an attractive clue to design novel anti-tumor strategies to overcome the Oxa resistance in hepatoma.