【摘要】 目的:研究microRNA181a(miR-181a)在人急性髓系白血病(AML)中的作用及其调控机制。方法:采用miR-181a小分子类似物转染人AML细胞系HL-60细胞,采用CCK-8计数法检测miR-181a对细胞增殖的影响。利用生物信息学方法结合文献分析预测miR-181a潜在的靶基因,通过双荧光报告实验在HL-60细胞内以及白血病患者体内多方面对靶基因进行验证。结果:miR-181a能显著促进人HL-60细胞恶性增殖(P<0.05);在线软件预测发现,抑癌基因ATM可能是白血病细胞miR-181a潜在的靶基因;双荧光报告实验结果表明,miR-181a能显著地抑制含3’-UTR的ATM报告基因活性,荧光素酶活性下降56.8%(P<0.01),而对含3’-UTR突变位点的ATM报告基因载体没有抑制作用。在HL-60细胞中过表达miR-181a,Western blot检测显示可以显著抑制内源性ATM的表达(P<0.01),而在白血病患者中miR-181a的表达增高,与ATM的表达呈负相关(r=-0.766)。结论:miR-181a通过抑制抑癌基因ATM表达以促进人AML细胞恶性增殖,从而在AML发病中起着类似"癌基因"的作用。更多还原

【Abstract】 Objective:To investigate miR-181 a function and regulation mechanism by identifying miR-181 a target genes in acute myeloid leukemia(AML).Methods:The HL-60 cells of human AML was transfected by small molecular analog miR-181 a,the cell proliferation was detected by CCK-8 method after electroporation in HL-60 cell lines.Target genes of miR-181 a were predicted and analyzed by the bio informatics software and database.Target genes were confirmed by HL-60 cell line and the patient leukemia cells.Results:Overexpressed miR-181 a in HL-60 cell line significantly enhanced cell proliferation compared with that in control(P < 0.05).Dual luciferase reporter gene assay showed that miR-181 a significantly suppressed the reporter gene activity containing ATM 3’-UTR by about 56.8%(P <0.05),but it didnt suppress the reporter gene activity containing 3’-UTR ATM mutation.Western blot showed that miR-181 a significantly downregulated the expression of ATM in human leukemia cells.It is also found that miR-181 a was significantly increased in AML,which showed a negative correlation with ATM expression.Conclusion:miR-181 a promotes cell proliferation in AML by regulating the tumor suppressor ATM,thus it plays the role as oncogene in pathogenesis of AML.更多还原