Development of a hypoxia-responsive vector for tumor-specific gene therapy
Development of a hypoxia-responsive vector for tumor-specific gene therapy
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DOI：
10.1038/sj.gt.3301124
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发表时间：
2000-03-01
期刊：
影响因子：
5.1
通讯作者：
Brown, JM
中科院分区：
文献类型：
--
作者：
Shibata, T;Giaccia, AJ;Brown, JM
我们正在开发新的基因治疗载体，其表达被缺氧选择性激活，这是人类实体瘤的独特特征。由于缺氧可上调血管内皮生长因子（VEGF）的表达，这种调控机制将使我们能够实现缺氧诱导的治疗基因的表达。具有来自人VEGF的5 '-非翻译区（UTR）的低氧应答元件（HRE）的五个拷贝的构建体在与肿瘤低氧相关的低氧张力下显示出优异的转录激活。为了获得更高的响应性，检查了HRE和启动子的各种组合。此外，我们还研究了VEGF基因的3' UTR是否会在缺氧条件下赋予增加的转录后mRNA稳定性。然而，尽管荧光素酶活性的缺氧/需氧比率增加，但由于富含AU的元件（战神）的mRNA不稳定，具有3' UTR的基因表达较低。因此，我们发现在我们的载体中包含3' UTR没有益处。在所有测试的载体中，5 HRE和CMV最小启动子的组合表现出与完整CMV启动子相似的水平的缺氧响应性（超过500倍）。我们建议该载体将用于肿瘤选择性基因治疗。
We are developing new gene therapy vectors whose expression is selectively activated by hypoxia, a unique feature of human solid tumors. As vascular endothelial growth factor (VEGF) is upregulated by hypoxia, such regulatory mechanisms would enable us to achieve hypoxia-inducible expression of therapeutic genes. Constructs with five copies of hypoxia-responsive elements (HREs) derived from the 5'-untranslated region (UTR) of the human VEGF showed excellent transcriptional activation at low oxygen tension relevant to tumor hypoxia. In an attempt to achieve higher responsiveness, various combinations of HREs and promoters were examined. In addition, we also investigated whether the 3' UTR of the VEGF gene would confer increased post-transcriptional mRNA stability under hypoxic conditions. However, despite increases in the hypoxic/aerobic ratio of luciferase activity, gene expression with 3' UTR was lower due to mRNA destabilization by AU-rich elements (AREs). Thus, we found no benefit from the inclusion of the 3' UTR in our vectors. Of all the vectors tested, the combination of 5HRE and a CMV minimal promoter exhibited hypoxia responsiveness (over 500-fold) to the similar level to the intact CMV promoter We propose that this vector would be useful for tumor selective gene therapy.