Grant E S, Brown T, Roach A, Williams B C, Habib F K
University Department of Surgery, University of Edinburgh, Western General Hospital, Scotland.
J Clin Endocrinol Metab. 1997 Feb;82(2):508-13. doi: 10.1210/jcem.82.2.3724.
RT-PCR analysis of total RNA prepared from the prostate cancer cell lines DU145 and PC3 and from primary epithelial cells indicated the presence of endothelin-1 (ET-1) messenger RNA (mRNA). Neither the LNCaP cell line nor primary prostatic stromal cells possess ET-1 mRNA transcripts. Seventy-two-hour-conditioned media derived from DU145, PC3, and primary epithelia contain immunoreactive ET concentrations equivalent to 0.814 +/- 0.048, 0.330 +/- 0.050, and 0.856 +/- 0.055 fmol/mL/10(6) cells after 72 h, respectively. Basal immunoreactive ET secretion was exhibited by LNCaP (0.029 +/- 0.009 fmol/mL/10(6) cells after 72 h) and stromal cells (0.067 +/- 0.007 fmol/ mL/10(6) cells after 72 h). Examination of ETA and ETB gene expression by RT-PCR demonstrates that ET receptor mRNA is almost completely undetectable in the prostate cancer cell lines. Both ETA and ETB mRNAs are detectable in primary cultures of prostatic epithelia and stroma. Competitive binding studies demonstrate a single class of binding site in both primary benign epithelia (dissociation constant = 1.85 x 10(-10) mol/L; maximal binding capacity = 2.7 x 10(4) binding sites/cell), and stroma (dissociation constant = 1.93 x 10(-10) mol/L; maximal binding capacity = 3.7 x 10(5) binding sites/cell). Use of selective ET receptor antagonists confirmed that the predominant stromal receptor subtype expressed in vitro is ETB. This receptor seems not to be coupled to mitogenic pathways because no growth response to exogenous ET-1 or cooperation between ET-1 and bFGF could be observed. Similarly, no effect of ET-1 or the ET-converting enzyme inhibitor, phosphoramidon, on benign epithelial cells could be observed over a 4-day period.
对从前列腺癌细胞系DU145和PC3以及原代上皮细胞中提取的总RNA进行逆转录聚合酶链反应（RT-PCR）分析，结果表明存在内皮素-1（ET-1）信使核糖核酸（mRNA）。LNCaP细胞系和原代前列腺基质细胞均不具有ET-1 mRNA转录本。来自DU145、PC3和原代上皮细胞的72小时条件培养基中，免疫反应性ET浓度在72小时后分别相当于0.814±0.048、0.330±0.050和0.856±0.055 fmol/mL/10⁶个细胞。LNCaP（72小时后为0.029±0.009 fmol/mL/10⁶个细胞）和基质细胞（72小时后为0.067±0.007 fmol/mL/10⁶个细胞）表现出基础免疫反应性ET分泌。通过RT-PCR检测ETA和ETB基因表达表明，在前列腺癌细胞系中几乎完全检测不到ET受体mRNA。在前列腺上皮和基质的原代培养物中均可检测到ETA和ETB mRNA。竞争性结合研究表明，在原发性良性上皮细胞（解离常数=1.85×10⁻¹⁰ mol/L；最大结合容量=2.7×10⁴个结合位点/细胞）和基质（解离常数=1.93×10⁻¹⁰ mol/L；最大结合容量=3.7×10⁵个结合位点/细胞）中均存在单一类别的结合位点。使用选择性ET受体拮抗剂证实，体外表达的主要基质受体亚型为ETB。该受体似乎未与促有丝分裂途径偶联，因为未观察到对外源性ET-1的生长反应或ET-1与碱性成纤维细胞生长因子（bFGF）之间的协同作用。同样，在4天的时间内未观察到ET-1或ET转换酶抑制剂磷酰胺素对良性上皮细胞有任何影响。
