Yu Duan, Jia William W, Gleave Martin E, Nelson Colleen C, Rennie Paul S
The Prostate Center at Vancouver General Hospital and the Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada.
Prostate. 2004 Jun 1;59(4):370-82. doi: 10.1002/pros.20010.
Lentiviruses are retroviruses that can infect and stably integrate into the chromatin of non-dividing cells. The purpose of this study was to determine whether lentiviral vectors containing the probasin (PB) promoter displayed prostate-specific, androgen-regulated, and persistent gene expression.
Three lentiviral-PB promoter/enhanced green fluorescent protein (EGFP)-reporter vectors together with a control lentiviral-CMV-EGFP, were tested by microscopy and flowcytometry for expression of EGFP after infection of human prostate cancer cells (LNCaP, PC-3, PC-3(hAR), and Du145 cells) and non-prostate cells (COS-1, HeLa, HeLa(hAR), and MCF-7 cells).
All cells infected in vitro with lentiviral-CMV vectors expressed EGFP, whereas with lentiviral-PB vectors (the most potent being Lv-ARR(2)PB), reporter expression was only observed in LNCaP cells with a small amount seen in androgen-independent PC-3 cells. Stable or transient transfection of androgen receptor only raised EGFP expression in prostate-derived cell lines, but did not change tumor specificity. With Lv-ARR(2)PB infected LNCaP cells, androgens regulated EGFP both in vitro and in vivo. After intra-tumor injection of this vector, EGFP expression was observed in LNCaP tumors, but not in A-549 lung or CaKi-2 kidney tumors.
Lv-ARR(2)PB may be an ideal vector for prostate-tumor targeting and for persistent, hormone-enhanced expression of a therapeutic gene to treat slow growing prostate tumors.
慢病毒是一种逆转录病毒，能够感染并稳定整合到非分裂细胞的染色质中。本研究的目的是确定含有前列腺特异性抗原（PB）启动子的慢病毒载体是否表现出前列腺特异性、雄激素调节和持续的基因表达。
通过显微镜和流式细胞术，检测三种慢病毒-PB启动子/增强型绿色荧光蛋白（EGFP）报告载体以及对照慢病毒-CMV-EGFP，在感染人前列腺癌细胞（LNCaP、PC-3、PC-3(hAR)和Du145细胞）和非前列腺细胞（COS-1、HeLa、HeLa(hAR)和MCF-7细胞）后EGFP的表达情况。
用慢病毒-CMV载体体外感染的所有细胞均表达EGFP，而用慢病毒-PB载体（最有效的是Lv-ARR(2)PB）感染时，仅在LNCaP细胞中观察到报告基因表达，在雄激素非依赖性PC-3细胞中观察到少量表达。雄激素受体的稳定或瞬时转染仅提高了前列腺来源细胞系中的EGFP表达，但未改变肿瘤特异性。用Lv-ARR(2)PB感染LNCaP细胞后，雄激素在体外和体内均调节EGFP的表达。在肿瘤内注射该载体后，在LNCaP肿瘤中观察到EGFP表达，但在A-549肺癌或CaKi-2肾癌肿瘤中未观察到。
Lv-ARR(2)PB可能是一种理想的载体，用于前列腺肿瘤靶向以及治疗生长缓慢的前列腺肿瘤的治疗基因的持续、激素增强表达。
