New oncolytic adenoviruses with hypoxia- and estrogen receptor-regulated replication
New oncolytic adenoviruses with hypoxia- and estrogen receptor-regulated replication
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DOI：
10.1089/104303402760293574
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发表时间：
2002-09-01
影响因子：
4.2
通讯作者：
Clarke, MF
中科院分区：
文献类型：
--
作者：
Hernandez-Alcoceba, R;Pihalja, M;Clarke, MF
如果病毒的关键转录单位的表达受组织或肿瘤特异性启动子控制，则可以产生具有限制复制的溶瘤腺病毒。在这里，我们描述了一种方法，用于将外源启动子快速掺入人腺病毒5型基因组的E1 A和E4区。使用这个系统，我们已经产生了AdEHT 2和AdEHE 2F，两个条件复制型腺病毒用于治疗乳腺癌。E1 A基因在两种病毒中的表达都是由一个最小的双特异性启动子控制的，该启动子对雌激素和缺氧有反应。E1 A表达的严格调节与这些病毒复制和杀死表达雌激素受体或在缺氧条件下维持的人类癌细胞的能力相关。端粒酶逆转录酶（TERT）启动子和E2 F-1启动子在癌细胞中优先活化。将它们分别引入AdEHT 2和AdEHE 2F的E4区。端粒酶核心启动子未能阻断病毒在端粒酶阴性细胞中的复制。相反，AdEHE 2F在常氧条件下生长的非转化静止细胞中减弱，表明具有低水平E2 F转录因子的完整pRB途径作为病毒的负调节剂。这些数据表明，通过适当的启动子组合同时调节E1 A和E4病毒转录单位可以增加溶瘤腺病毒的肿瘤选择性。
Oncolytic adenoviruses with restricted replication can be produced if the expression of crucial transcription units of the virus is controlled by tissue-or tumor-specific promoters. Here we describe a method for the rapid incorporation of exogenous promoters into the E1A and E4 regions of the human adenovirus type 5 genome. Using this system, we have generated AdEHT2 and AdEHE2F, two conditionally replicative adenoviruses for the treatment of breast cancer. The expression of the E1A gene in both viruses is controlled by a minimal dual-specificity promoter that responds to estrogens and hypoxia. The tight regulation of E1A expression correlated with the ability of these viruses to replicate and kill human cancer cells that express estrogen receptors, or are maintained under hypoxic conditions. The telomerase reverse transcriptase (TERT) promoter and the E2F-1 promoter are preferentially activated in cancer cells. They were introduced into the E4 region of AdEHT2 and AdEHE2F, respectively. The telomerase core promoter failed to block the replication of the virus in telomerase-negative cells. In contrast, AdEHE2F was attenuated in nontransformed quiescent cells growing under normoxic conditions, suggesting that an intact pRB pathway with low levels of E2F transcription factors acts as a negative modulator for the virus. These data indicate that the simultaneous regulation of E1A and E4 viral transcription units by the appropriate combination of promoters can increase the tumor selectivity of oncolytic adenoviruses.