Prostate targeting: PSP94 gene promoter/enhancer region directed prostate tissue-specific expression in a transgenic mouse prostate cancer model
Prostate targeting: PSP94 gene promoter/enhancer region directed prostate tissue-specific expression in a transgenic mouse prostate cancer model
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DOI：
10.1038/sj.gt.3301895
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发表时间：
2002-12-01
期刊：
影响因子：
5.1
通讯作者：
Xuan, JW
中科院分区：
文献类型：
--
作者：
Gabril, MY;Onita, T;Xuan, JW
迄今为止，只有少数前列腺特异性载体基因已被测试用于前列腺癌（CaP）的基因治疗中的前列腺靶向。目前CaP基因治疗的临床试验利用仅有的两种可用的载体基因与腺病毒载体中的大鼠probasin启动子和人PSA启动子序列的组合来靶向CaP。迫切需要建立额外的载体基因系统来维持和传播当前的研究。由于PSP 94（94个氨基酸的前列腺分泌蛋白）是人类前列腺分泌的三种最丰富的蛋白质之一，并且通常被认为在人类和啮齿动物中是前列腺组织特异性的，我们进行了转基因实验以评估PSP 94基因导向的前列腺靶向的启动子/增强子区域。首先，构建了一系列与报告基因LacZ连接的3.84 kb PSP 94基因启动子/增强子区（包括内含子1序列的部分）的进行性缺失突变体，并在体外细胞培养中进行了评估。接下来，使用SV 40早期区域（Tag癌基因）作为选择标记，用两种转基因构建体产生转基因小鼠。通过免疫组化标记的Tag表达，证实了PSP 94基因启动子/增强子区域在小鼠中特异性地指导的SV 40 Tag表达在三个育种系（A，B，C，n = 374）中。通过SV 40 Tag诱导的肿瘤发生（肿瘤分级）与青春期和年龄（10-32周）的相关性，在组织学上表征了PSP 94基因导向的转基因CaP模型中对前列腺的特异性靶向。早在10周龄时就观察到前列腺增生，随后出现前列腺上皮内瘤变（PIN），最终出现前列腺高级别癌。PSP 94转基因小鼠CaP模型的进一步特征在于其在20周龄时的肿瘤进展和转移趋势，以及其对雄激素操作的反应性和难治性。本研究表明，PSP 94基因启动子/增强子具有前列腺特异性靶向的潜力，并可能最终用于CaP的基因治疗。
To date, only a few prostate-specific vector genes have been tested for prostate targeting in gene therapy of prostate cancer (CaP). Current clinical trials of gene therapy of CaP utilize the only two available vector genes with a combination of a rat probasin promoter and a human PSA promoter sequence in an adenovirus vector to target CaP. There is an urgent need to establish additional vector gene systems to sustain and propagate the current research. Since PSP94 (prostate secretory protein of 94 amino acids) is one of the three most abundant proteins secreted from the human prostate and is generally considered to be prostate tissue-specific in both human and rodents, we performed a transgenic experiment to assess the promoter/enhancer region of PSP94 gene-directed prostate targeting. Firstly, a series of progressive deletion mutants of a 3.84 kb PSP94 gene promoter/enhancer region (including parts of the intron 1 sequence) linked with a reporter LacZ gene was constructed and assessed in vitro in cell culture. Next, transgenic mice were generated with two transgene constructs using the SV40 early region (Tag oncogene) as a selection marker. PSP94 gene promoter/enhancer region-directed SV40 Tag expression specifically in the mouse was demonstrated in three breeding lines (A, B, C, n = 374) by immunohistochemistry staining of Tag expression. Specific targeting to the prostate in the PSP94 gene-directed transgenic CaP model was characterized histologically by correlation of SV40 Tag-induced tumorigenesis (tumor grading) with puberty and age (10-32 weeks). Prostatic hyperplasia was observed as early as 10 weeks of age, with subsequent emergence of prostatic intraepithelial neoplasia (PIN) and eventually high grade carcinoma in the prostate. The PSP94 transgenic mouse CaP model was further characterized by its tumor progression and metastatic tendency at 20 weeks of age and also by its responsiveness and refractoriness to androgen manipulation. This study indicates that the PSP94 gene promoter/enhancer has the potential for prostate specific targeting and may ultimately be of use in gene therapy of CaP.