Zeng Hao, Liao Yong-Chuan, Wang Fang, Wu Qi, Yang Yu-Ru
Department of Urology, West China Hospital of Sichuan University, Chengdu 610041, China.
Sichuan Da Xue Xue Bao Yi Xue Ban. 2005 Nov;36(6):782-5.
To assess the specificity of prostate-specific membrane antigen(PSMA) promoter and enhancer in controlling gene expression and to compare the activity of enhancers in different directions for choosing the most suitable prostate-specific PSMA controlling elements.
PSMA enhancer gene was amplified with PCR, then the enhancer gene was subcloned into the expressing vector pEGFP-PSMA(Pro) reversely to construct the recombinant plasmid pEGFP-PSMA(E(r)-p), which was transfected into different cell lines such as LNCaP, PC-3,MCF-7,A549. Green fluorescent protein (GFP) expression was observed and compared to other recombinants constructed previously.
The recombinant plasmid with reverse enhancer was successfully constructed, the PSMA promoter and enhancer showed modulating activity in PSMA-expressed cell line uniquely. PSMA enhancer could increase 30-fold transcriptional activity over the basal level achieved by PSMA promoter alone, and no impact of the direction on the activity of enhancer was noted.
PSMA promoter/ enhancer is specific to PSMA-expressed cells. The transcriptional activity of reverse enhancer is similar to that of enhancer. PSMA promoter/enhancer has the potential for use in targeted gene therapy of prostate adenocarcinoma.
评估前列腺特异性膜抗原（PSMA）启动子和增强子在控制基因表达方面的特异性，并比较不同方向增强子的活性，以选择最合适的前列腺特异性PSMA调控元件。
采用PCR扩增PSMA增强子基因，然后将增强子基因反向亚克隆到表达载体pEGFP-PSMA(Pro)中，构建重组质粒pEGFP-PSMA(E(r)-p)，将其转染至LNCaP、PC-3、MCF-7、A549等不同细胞系。观察绿色荧光蛋白（GFP）表达情况，并与之前构建的其他重组体进行比较。
成功构建了含反向增强子的重组质粒，PSMA启动子和增强子仅在PSMA表达的细胞系中显示出调控活性。PSMA增强子可使转录活性比单独的PSMA启动子所达到的基础水平提高30倍，且未发现增强子活性受方向影响。
PSMA启动子/增强子对PSMA表达细胞具有特异性。反向增强子的转录活性与增强子相似。PSMA启动子/增强子有潜力用于前列腺腺癌的靶向基因治疗。
