Combinatorial Control of Suicide Gene Expression by Tissue-specific Promoter and microRNA Regulation for Cancer Therapy
Combinatorial Control of Suicide Gene Expression by Tissue-specific Promoter and microRNA Regulation for Cancer Therapy
复制标题
DOI：
10.1038/mt.2009.225
复制
发表时间：
2009-12-01
影响因子：
12.4
通讯作者：
Wang, Shu
中科院分区：
文献类型：
--
作者：
Wu, Chunxiao;Lin, Jiakai;Wang, Shu
使用组织特异性细胞启动子的转录靶向被证明是限制转基因在靶组织中表达的有力手段。在癌症自杀基因治疗的背景下，这种方法可能会导致对癌症和非靶向正常细胞的细胞毒效应。考虑到microRNA(MiRNA)在转录后基因表达调控中的作用，我们开发了一种基于细胞启动子的转录靶向和miRNA调控相结合的病毒载体平台，用于小鼠脑内胶质瘤自杀基因的治疗。该疗法在单个杆状病毒载体中利用胶质纤维酸性蛋白(GFAP)基因启动子和三个在星形胶质细胞中表达下调的miRNAs的重复靶序列来控制单纯疱疹病毒胸苷激酶(HSVtk)基因的表达。与使用没有miRNA调控的对照载体相比，这显著提高了体内选择性，使人胶质瘤异种移植能够有效消除，同时对正常星形胶质细胞产生的毒性效应可以忽略不计。因此，将miRNA调控整合到转录靶向载体中增加了一层额外的安全层，以防止非靶标转基因表达，并将有助于开发具有高靶向特异性的癌症治疗基因递送载体。
Transcriptional targeting using a tissue-specific cellular promoter is proving to be a powerful means for restricting transgene expression in targeted tissues. In the context of cancer suicide gene therapy, this approach may lead to cytotoxic effects in both cancer and nontarget normal cells. Considering microRNA (miRNA) function in post-transcriptional regulation of gene expression, we have developed a viral vector platform combining cellular promoter-based transcriptional targeting with miRNA regulation for a glioma suicide gene therapy in the mouse brain. The therapy employed, in a single baculoviral vector, a glial fibrillary acidic protein (GFAP) gene promoter and the repeated target sequences of three miRNAs that are enriched in astrocytes but downregulated in glioblastoma cells to control the expression of the herpes simplex virus thymidine kinase (HSVtk) gene. This resulted in significantly improved in vivo selectivity over the use of a control vector without miRNA regulation, enabling effective elimination of human glioma xenografts while producing negligible toxic effects on normal astrocytes. Thus, incorporating miRNA regulation into a transcriptional targeting vector adds an extra layer of security to prevent off-target transgene expression and should be useful for the development of gene delivery vectors with high targeting specificity for cancer therapy.