Tumor-specific suicide gene therapy for hepatocellular carcinoma by transcriptionally targeted retroviral replicating vectors
Tumor-specific suicide gene therapy for hepatocellular carcinoma by transcriptionally targeted retroviral replicating vectors
复制标题
DOI：
10.1038/gt.2014.98
复制
发表时间：
2015-02-01
期刊：
影响因子：
5.1
通讯作者：
Tai, C-K
中科院分区：
文献类型：
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作者：
Lai, Y-H;Lin, C-C;Tai, C-K
复制病毒载体是抗癌基因治疗的有吸引力的工具，但由于载体的不受控制的传播而导致的潜在不良事件一直是主要关注的问题。为了设计肿瘤特异性逆转录病毒复制载体（RRV），我们用由B肝炎病毒增强子II（EII）和人甲胎蛋白（AFP）核心启动子组成的调控序列替换RRV ACE-GFP的U3区，以产生ACE-GFP-EIIAFP，一种肝细胞癌（HCC）靶向RRV。与ACE-GFP类似，ACE-GFP-EIIAFP在HCC细胞中表现出稳健的绿色荧光蛋白（GFP）表达，最重要的是，它表现出HCC特异性复制，并且在非HCC肿瘤细胞或正常肝细胞中不复制。我们对从连续感染循环中收集的ACE-GFP-EIIAFP的启动子区域进行测序，以检查载体在其复制传播期间的基因组稳定性，并发现载体可以在基因组中保留杂交启动子至少6个感染循环。体外研究表明，ACE-CD-EIIAFP和ACE-PNP-EIIAFP分别表达酵母胞嘧啶脱氨酶和大肠杆菌嘌呤核苷磷酸化酶，在其各自前药存在下对HCC细胞产生高度有效的细胞毒性作用。在体内，ACE-CD-EIIAFP介导的自杀基因治疗有效地抑制了HCC肿瘤的生长，并且在瘤外组织中没有观察到可检测的RRV信号。这些结果表明，肿瘤特异性，自杀基因编码的RRV可能实现逆转录病毒基因治疗癌症的承诺。
Replicating virus vectors are attractive tools for anticancer gene therapy, but the potential for adverse events due to uncontrolled spread of the vectors has been a major concern. To design a tumor-specific retroviral replicating vector (RRV), we replaced the U3 region of the RRV ACE-GFP with a regulatory sequence consisting of the hepatitis B virus enhancer II (EII) and human alpha-fetoprotein (AFP) core promoter to produce ACE-GFP-EIIAFP, a hepatocellular carcinoma (HCC)-targeting RRV. Similar to ACE-GFP, ACE-GFP-EIIAFP exhibited robust green fluorescent protein (GFP) expression in HCC cells and, most importantly, it exhibited HCC-specific replication and did not replicate in non-HCC tumor cells or normal liver cells. We sequenced the promoter region of ACE-GFP-EIIAFP collected from serial infection cycles to examine the genomic stability of the vector during its replicative spread, and found that the vector could retain the hybrid promoter in the genome for at least six infection cycles. In vitro studies revealed that ACE-CD-EIIAFP and ACE-PNP-EIIAFP, which express the yeast cytosine deaminase and Escherichia coli purine nucleoside phosphorylase, respectively, exert a highly potent cytotoxic effect on HCC cells in the presence of their respective prodrugs. In vivo, ACE-CD-EIIAFP-mediated suicide gene therapy efficiently suppressed HCC tumor growth and no detectable RRV signal was observed in extratumoral tissues. These results suggest that the tumor-specific, suicide-gene-encoding RRV may fulfill the promise of retroviral gene therapy for cancer.