异常表观遗传沉默miRNAs对恶性血液病细胞Ras通路的激活作用

项目名称： 异常表观遗传沉默miRNAs对恶性血液病细胞Ras通路的激活作用

项目编号： No.81200391

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 医学一处

项目作者： 杨洋

作者单位： 中国人民解放军空军总医院

项目金额： 23万元

中文摘要： 已有的研究表明在恶性血液病细胞中,miR-203、miR-34a和miR-663是受异常的表观遗传学沉默或下调的miRNAs。我们既往的研究表明，miR-663可负性调控H-ras基因表达，而Ras信号传导通路上游分子SRC表达水平可能受miR-203及miR-34a调节。那么这三个微小RNA表达的下调，是否会引起Ras信号传导通路过度的激活目前尚不十分清楚。本研究中，拟在由启动子区CpG岛异常甲基化导致三种微小RNA表达下调的细胞系中，探讨这种改变对Ras信号传导通路激活作用的分子机理和对细胞恶性转化的作用。通过慢病毒介导miR-203、miR-34a及miR-663高表达，检测Ras信号通路中的下游分子的变化和由此带来的对细胞的增殖、周期、表型的影响。本研究的意义在于，有助于丰富对Ras信号传导通路过度激活的分子机制的认识，为此类恶性血液病下一步的靶向治疗提供潜在的理论依据。

中文关键词： miR-34a；c-SRC；甲基化；表观遗传；伊马替尼抵抗

英文摘要： Some research showed that miR-203,miR-34a and miR-663 were silenced or down-regulated due to aberrant epigenetic regulation in the hematological malignant cells.In our previous study, the miR-663 could down-regulate H-ras expression, meanwhile the SRC that was the signal molecule in upstream region of the Ras signaling pathway,which was regulated by miR-203 and miR-34a potentially. But it is not clear if the signaling pathway of Ras will be activated because of the down-regulation of the three miRNAs. In the research, the aim was to discover the molecular mechanism of activating Ras signaling pathway and inducing malignant transformation due to the changes in epigenetic regulation in the cell lines , in which the three miRNAs expression were silenced or down-regulation because the CpG islands were methylation in the promoter regions. After the miR-203,miR-34a and miR-663 were over-expressed with the means of lentivirus vector, the expression of downstream molecules in the Ras signaling pathway were detected, then to ascertain the effects on cell proliferation, cell cycle and cell phenotype. The significance of this study is to help to enrich the understanding of the molecular mechanism of the excessive activation of the Ras signal transduction pathway and provide a potential theoretical basis for targeted thera

英文关键词： miR-34a；c-SRC；methylation；epigenetic；imatinib-resistant