miRNA激活p21基因表达机制及在膀胱肿瘤靶向治疗作用研究

Short non coding RNA (ncRNA) can not only inhibit gene expression, but also specifically activate the expression of silenced or low expressed genes. The latter mechanism thus hold great potential for gene function research and gene targeting therapy. We have studied ncRNA activation mechanism for many years and found that external small double-stranded RNA molecules can significantly activate gene expression, and some endogenous microRNA(miRNA) also can activate corresponding gene expression. We will use human bladder tumor cell lines T24 and J82 and xenograft bladder tumor model to screen miRNAs which can activate p21 gene expression by targeting p21 gene promoter sequence. We will then construct miRNA expression vectors to detect miRNAs on p21 gene activation effect and understand the underlying mechanism, and to evaluate potential biological effect following p21 activation. This study will provide new insight to RNAa mechanism and practival methods for screening and identifying miRNAs with gene activation function, and will also provide proof of principle for treating tumor diseases with activating miRNAs.

小分子非编码RNA（ncRNA）不仅具有抑制基因表达的功能，而且还可以序列特异性地激活沉默或低表达基因，后者在基因功能研究及基因靶向治疗方面具有诱人的潜力。我们针对ncRNA激活机制进行了多年研究，发现外源性引入小双链非编码RNA分子能显著激活基因的表达，并发现某些内源性的微小单链RNA分子（miRNA）也具有激活相应基因表达功能。本研究以人膀胱肿瘤细胞株T24和J82及裸鼠异位膀胱肿瘤模型为研究对象，筛选针对p21基因启动子区域DNA序列的具有激活p21基因表达功效的miRNA分子，构建miRNA表达载体，检测miRNA分子对p21基因表达的激活效应及机制，以及基因激活后的生物学效应。通过本研究，有望对现有RNA激活机制的进行合理的补充和完善，并建立起一套简单有效的筛选和鉴定具有激活功效的小分子ncRNA的方法，为利用RNA激活机制靶向治疗肿瘤性疾病进行可行性研究。