Optimization of a synthetic β-catenin-dependent promoter for tumor-specific cancer gene therapy
Optimization of a synthetic β-catenin-dependent promoter for tumor-specific cancer gene therapy
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用于肿瘤特异性癌症基因治疗的合成β-连环蛋白依赖性启动子的优化
DOI：
10.1016/j.ymthe.2004.03.021
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发表时间：
2004
影响因子：
12.4
通讯作者：
C. Wrighton
中科院分区：
文献类型：
--
作者：
K. Lipinski;Hakim A Djeha;J. Gawn;S. Cliffe;N. Maitland;D. Palmer;A. Mountain;A. Irvine;C. Wrighton
我们最近发表了β-catenin依赖性、高活性启动子CTP1的构建和评价，以及其在腺病毒（Ad）载体的基因导向酶前药物治疗中治疗结直肠癌的可能应用。替代的基于Ad的方法，如肿瘤特异性、复制能力强的载体和/或利用具有内在毒性活性的治疗性基因产物，如长毛猿白血病病毒融合膜糖蛋白、白喉毒素A （DTA）和蓖麻毒素，将需要一个非常严格调控的启动子，以避免在非肿瘤组织和Ad产生细胞系中突破性复制和毒性。在这项研究中，我们通过改变其基础启动子、Tcf结合位点的数量以及这些与基础启动子之间的距离来优化合成的β-catenin依赖启动子的活性/特异性。最佳启动子CTP4在β-catenin调节正常的细胞中几乎检测不到表达，但在β-catenin调节不正常的细胞中却有高水平表达。据我们所知，使用CTP4，我们第一次能够生成一个表达完全活跃的野生型DTA的广告向量，而不需要耗时和繁琐的制作系统。CTP4应该是β-连环蛋白失调肿瘤基于ad基因治疗的首选启动子。我们提供的初步证据表明，这些可能包括前列腺癌、卵巢癌以及结直肠癌。
We recently published the construction and evaluation of a β-catenin-dependent, highly active promoter, CTP1, and its possible application for the treatment of colorectal cancer using gene-directed enzyme prodrug therapy with adenoviral (Ad) vectors. Alternative Ad-based approaches such as tumor-specific, replication-competent vectors and/or exploiting therapeutic gene products with intrinsic toxic activity, such as gibbon ape leukemia virus fusogenic membrane glycoprotein, diphtheria toxin A (DTA), and ricin, would demand a very tightly regulated promoter to avoid breakthrough replication and toxicity in nontumor tissue and Ad producer cell lines. In this study we optimized the activity/specificity profile of the synthetic β-catenin-dependent promoter by varying its basal promoter, the number of Tcf binding sites, and the distance between these and the basal promoter. The optimal promoter, CTP4, showed virtually undetectable expression in cells with normal β-catenin regulation but high level expression in cells deregulated for β-catenin. Using CTP4 we were able to generate, for the first time to our knowledge, an Ad vector expressing fully active wild-type DTA without the need for time-consuming and cumbersome production systems. CTP4 should be the promoter of choice for Ad-based gene therapies of tumors deregulated for β-catenin. We provide preliminary evidence that these may include prostate and ovarian as well as colorectal cancer.