锤头状核酶阻断雄激素受体基因表达的研究

目的　探讨核酶 (RZ)在细胞水平调节雄激素受体 (AR)基因表达的作用。方法　设计并合成针对AR的锤头状核酶序列 ,分子克隆技术构建活性核酶和无活性核酶表达载体 ,脂质体介导下转染雄激素受体表达阳性细胞株T47D。转染第 1～ 3天 ,应用免疫组织化学和逆转录 聚合酶链反应 (RT PCR)技术检测细胞内AR基因表达水平。结果　AR活性核酶表达载体转染后 ,T47D细胞ARmRNA水平降低 2 2 .4%～ 50 .7% (P <0 .0 5) ,AR蛋白阳性细胞减少 7.1 0 %～1 1 .90 % (P <0 .0 5)。而无活性核酶对细胞AR基因表达差异无显著性 (P >0 .0 5)。结论　成功构建AR锤头状核酶表达载体 ,能特异性切割ARmRNA ,阻断雄激素受体基因表达     

反义寡核苷酸阻断雄激素受体表达对前列腺癌细胞生长活性的影响

目的　探讨反义技术阻断雄激素受体 (AR)基因表达对前列腺癌细胞生长的影响。　方法　设计、合成针对AR基因反义寡核苷酸 (ASODN) ,在脂质体介导下转染前列腺癌细胞。采用RT PCR方法检测AR基因表达 ;MTT比色法检测细胞增殖活性 ;透射电镜、TUNEL检测细胞凋亡 ;流式细胞术分析细胞周期时相。　结果　 0 .5～ 2 .0 μmol LASODN作用 12～ 36h ,癌细胞ARmRNA水平降低 10 .45 %～ 82 .10 %(P <0 .0 5 ) ,细胞增殖活性抑制 11.8%～ 5 6 .9%(P <0 .0 5 ) ,细胞周期阻滞于G2 M期 ,部分细胞呈现典型凋亡形态学改变 ,凋亡比率为 34.2 5 %(P <0 .0 1)。　结论　应用ASODN封闭AR基因表达能抑制前列腺癌细胞体外生长活性 ,有望成为前列腺癌基因治疗的有效策略。     

前列腺癌雄激素依赖转化后细胞内雄激素受体表达变化的研究

目的：探讨雄激素受体（AR）在前列腺癌雄激素依赖特性转化过程中的作用。方法：对33例晚期前列腺癌患者进行雄激素阻断治疗并作长时间随访,其间有18例发生了雄激素依赖转化．15例未发生雄激素依赖转化。采用免疫组织化学及RT—PCR法测定18例患者雄激素依赖转化前后及15例患者雄激素阻断治疗前后癌细胞内AR蛋白及AR基因的表达情况。结果：18例患者雄激素依赖转化前后AR蛋白及AR基因的表达分别为（1．33±0．97VS3．11±0．76）和（28．41±3．38Ct vs 36．73±1．81Ct）,两者之间差异有统计学意义（P〈0．01）;15例患者雄激素阻断治疗前后AR蛋白及AR基因的表达分别为（1．47±0．83 vs 1．40±0．99）和（29．50±3．08Ct vs29．14±3．23Ct）,两者之间差异无统计学意义（P〉0．05）。结论：AR基因及AR蛋白表达增强是前列腺癌雄激素依赖转化的原因之一。     

脑膜瘤细胞增殖与雄激素受体表达的关系

目的 探讨脑膜瘤细胞增殖与雄激素受体（AR）表达的关系。方法 用免疫组织化学链霉亲和素－生物素复合物（SABC）法检测39例脑膜瘤中AR和增殖细胞核抗原（PCNA）的表达。结果 良性、非典型性、恶性脑膜瘤AR表达率分别为31．0％、58．0％、87．5％。恶性脑膜瘤AR阳性表达率和AR阳性细胞数显著于高非典型性和良性脑膜瘤（P＜0．05）。AR阳性脑膜瘤中PCNA标记指数（PCNA LI）高于AR阴性的脑膜瘤（P＜0．01）,脑膜瘤中AR表达与PCNA LI相关。结论 AR过度表达促进脑膜瘤细胞异常增殖,在脑膜瘤的发生发展过程中起重要作用。     

人肝细胞性肝癌性激素受体的表达

目的：研究人肝细胞性肝癌组织、癌旁组织和正常肝组织中雄激素受体（AR）和雌激素受体（ER）的表达水平及分布规律。方法：应用单克隆抗体免疫组化法检测50例肝细胞性肝癌标本的肿瘤组织、癌旁组织和10例肝内胆管结石的肝组织中AR和ER的表达情况。结果：在肝癌组织、癌旁组织和肝内胆管结石的肝组织中，AR的阳性表达率分别为30％、8％和0％，除癌组织显著高于癌旁组织外（P＜0．01），其它各组无显著性差异（P＞0．05）；ER的阳性表达率分别为12％、10％和20％，在三组中均无显著性差异（P＞0．05），在所有阳性片中，AR和ER的标记指数（LI）均＜25。结论：AR和ER在肝细胞性肝癌组织中的表达率很低。     

siRNA 干扰雄激素受体相互作用蛋白 HSPBAP1对人前列腺癌 PC3细胞恶性表型的影响

目的：探讨siRNA干扰雄激素受体相互作用蛋白HSPBAP1对前列腺癌PC3恶性表型的影响。方法 siRNA干扰PC3细胞HSPBAP1的表达,检测细胞增殖、克隆形成、细胞周期及迁移和侵袭的变化。结果 siHSPBAP1组与对照组相比,增殖能力、克隆形成能力、迁移和侵袭能力显著减弱（ P ＜0．05）, G0／G1期细胞数增多,S期和G2／M期细胞数显著减少（ P ＜0．05）。结论干扰HSPBAP1能够抑制前列腺癌PC3细胞的恶性表型。     

BAK基因过表达对膀胱癌细胞的诱导凋亡作用及其分子机制

目的：探讨BAK基因过表达对膀胱癌的诱导凋亡效应及机制。方法：脂质体介导BAK基因转染膀胱癌EJ细胞1－7d后，逆转录聚合酶链反应检测BAK基因表达，细胞计数法检测癌细胞生长活性，DNA Ladder法、吖啶橙－溴化乙锭荧光染色法及原位末端转移酶标记技术检测癌细胞凋亡，免疫组织化学法检测癌细胞Caspase-3、Bcl-2,p53表达。结果：转染1－7d后，癌细胞BAK基因表达显著增强（P＜0．01），体外生长抑制20．66％－35．58％（P＜0．01），部分癌细胞呈现凋亡形态学变化，凋亡率为18．0％－20．6％（P＜0．01），癌细胞Caspase-3表达增强6．6倍（P＜0．01）Bcl．2和P53表达差异无显著性（P＞0．05）。结论：BAK基因表达能显著诱导膀胱癌细胞凋亡，其中Caspase-3激活是其作用机制之一。     

雄激素对前列腺癌细胞PAR基因表达的影响及其机制

目的观察在前列腺癌特异性高表达的癌基因前列腺雄激素调节基因（PAR）对雄激素的反应及其机制，探讨通过抑制PAR基因治疗雄激素非依赖性前列腺癌的可能性。方法用细胞计数检测双氢睾酮对LNCaP、PC3细胞增殖的刺激效应，以逆转录-聚合酶链反应（RT-PCR）分别检测双氢睾酮对LNCaP、PC3细胞PAR基因mRNA表达水平的影响及双氢睾酮和其拮抗剂联合作用对LNCaP细胞PAR基因mRNA表达水平的影响。结果低浓度（0．001～1nmol／L）双氢睾酮刺激可促进LNCaP细胞增殖，且刺激效应随双氢睾酮浓度升高而增强，在0．1nmol／L浓度时达最大，细胞计数为（27、54±0．71）×10。爪／孔，为对照组（16．13±1．03）×10。爪／孔的（170．74±0．78）％；同时使PAR基因mRNA表达水平上调在0．1nmol／L浓度时最高，为对照组的（272．42±8．24）％，P〈0．05）；高浓度（10、100nmol／L）双氢睾酮则抑制其增殖和PAR基因表达，在10nmol／L和100nmol／L浓度，细胞计数分别为（12．02±0．41）×10。／孔、（11．13±1．92）×10^4／孔（P〈0．05）；PAR基因mRNA表达水平分别为对照组的（76．64±2．47）％和（52．97±1．07）％，（P〈0．05）。这一调节效应可以为氟他胺所阻断。双氢睾酮对PC3细胞生长及PAR基因mRNA表达无明显影响（P〉0．05）。结论PAR可能是雄激素．雄激素受体通路下游的前列腺癌特异性癌基因，有望成为雄激素非依赖性前列腺癌基因和药物治疗的潜在靶点。     

雄激素受体在前列腺癌中表达和意义的探讨

目的 探讨雄激素受体（AR）在PCa中的表达和意义。方法 应用免疫组化Elivison法，检测45例PCa和10例前列腺增生组织标本中AR的表达，并探讨AR蛋白表达与PCa分期、分级、术前PSA、内分泌治疗效果及预后的关系。结果 AR在PCa和前列腺增生中阳性表达率分别为90％和93、3％，阳性表达率和表达程度无显著性差异（P〉0.05）；D期和A-C期PCa中阳性表达率分别为100％和87．5％，无显著差异（P〉0．05）．但D期PCa AR阳性表达程度显著增强（P〈0．05）；Gleason评分≤7和Gleason评分〉7PCa中阳性表达率分别为85.7％和100％，无显著差异（P〉0.05），但低分化PCa（Gleason评分〉7）AR阳性表达程度显著增强（P〈0．05）：PSA≤10ng／ml和PSA〉10ng／mlPEa中阳性表达率分别为80％和97.1％，阳性表达率和表达程度无显著性差异（P〉0．05）：在内分泌治疗有效和无效PCa中阳性表达率分别为87．5％和90、9％，阳性表达率和表达程度无显著性差异（P〉0．05）。结论 AR阳性表达程度与PCa分期、分级有关，对判断PCa生物学行为有参考价值。     

雄激素受体反义寡核苷酸对前列腺癌细胞生长的抑制作用

目的　探讨雄激素受体 (AR)反义寡核苷酸 (aODN)对前列腺癌细胞AR表达和生长的抑制作用。　方法　合成 1对AR正、反义寡核苷酸 ,与LNCaP细胞共培养 ,观察LNCaP细胞的增殖情况 ,RT PCR和Westernblot方法检测ARmRNA水平和AR蛋白表达水平。　结果　含ARaODN的培养基培养处于静止期和对数生长期的LNCaP细胞增殖较对照组均明显减慢。RT PCR证实aODN组吸光度A值 (0 .5 3± 0 .18)与ODN组 (1.14± 0 .2 1)差异有显著性意义 (P <0 .0 5 ) ,提示ARaODN可导致LNCaP细胞ARmRNA显著下调。Westernblot分析显示aODN组条带的吸光度A值 (2 6 .35± 1.33)与ODN组 (33.5 1± 1.4 8)之间差异有显著性意义 (P <0 .0 5 ) ,提示ARaODN可下调LNCaP细胞AR蛋白含量。　结论　ARaODN可抑制前列腺癌细胞AR表达并抑制前列腺癌细胞增殖。     

苦参碱对雄激素依赖性前列腺癌细胞的影响

目的：探讨苦参碱（Matrine）对雄激素依赖性前列腺癌细胞株（LNCaP）凋亡及前列腺特异抗原（prostate specific antigen,PSA）表达的影响。方法：分别用0.5g／L、1.0g／L、1.5g／L、2.0g／L浓度的苦参碱作用于LNCaP细胞12h、24h、36h后MTT法检测细胞生长活性;24h后流式细胞仪测定细胞凋亡的变化;24h后Western印迹法检测细胞内Bel-2和Bax的表达;12h、24h、36h后化学发光法检测LNCaP细胞培养液中PSA的变化。结果：苦参碱能抑制LNCaP细胞的生长,呈剂量与时间依赖性,不同浓度苦参碱组之间与不同作用时间组之间的差异均有统计学意义（P〈0.05）。苦参碱诱导LNCaP细胞凋亡,各浓度组凋亡细胞比例均显著高于对照组,差异有统计学意义（P〈0.05）;LNCaP细胞内Bcl-2含量呈浓度依赖性下降,Bax含量呈浓度依赖性升高（P〈0.01）;LNCaP细胞培养液中PSA的表达显著下降（P均〈0.05）。结论：苦参碱能显著抑制LNCaP细胞的体外生长,诱导其凋亡,并抑制PSA的表达。     

Prostate cancer cells generated during intermittent androgen ablation acquire a growth advantage and exhibit changes in epidermal growth factor receptor expression

BACKGROUND: Intermittent androgen ablation is a palliative treatment option for advanced prostate cancer which is associated with less side effects, improved quality of life of patients, and reduced costs. Regulation of growth and survival of prostate cancer cells during intermittent androgen withdrawal has not been studied in appropriate models yet. METHODS: Two cycles of androgen withdrawal and supplementation were performed in human prostate cancer cells LNCaP in vitro. Proliferation of prostate cancer cell sublines established after intermittent androgen withdrawal was assessed in the absence or presence of epidermal growth factor (EGF) by protein determination. Cell cycle was analyzed with a flow cytometer. EGF was measured in the supernatants of LNCaP sublines with a commercial ELISA. EGF receptor mRNA and protein were determined by real-time PCR and Western blot, respectively. RESULTS: Basal proliferation rate of all newly generated LNCaP sublines increased over that of the parental LNCaP cell line. The highest stimulation of proliferation by exogenous EGF was observed in parental LNCaP cells. In each LNCaP derivative established during intermittent androgen withdrawal, the percentage of cells in the S phase of cell cycle was higher than that in parental LNCaP cells. EGF levels did not increase during intermittent androgen ablation. The expression of EGF receptor protein decreased following each cycle of androgen ablation and increased subsequently after androgen supplementation. EGF receptor (EGFR) mRNA was regulated in a similar manner in LNCaP derivatives established during the second cycle of intermittent withdrawal. CONCLUSIONS: Changes in the expression of the EGF receptor occur during intermittent androgen ablation but they cannot be solely responsible for increased basal proliferation. Alternatively, other ligands and receptors of the EGF system may become overexpressed during prolonged withdrawal and supplementation of androgenic hormones in prostate cancer therapy.     

Prostate specific antigen expression does not necessarily correlate with prostate cancer cell growth

PURPOSE: The antiproliferative effects of pharmacological agents used for androgen ablative therapy in prostate cancer, including goserelin, bicalutamide and cyproterone acetate (Fluka Chemie, Buchs, Switzerland), were tested in vitro. It was determined whether they affected prostate specific antigen mRNA and protein expression independent of growth inhibition. MATERIALS AND METHODS: Goserelin, bicalutamide (AstraZeneca, Zug, Switzerland) and cyproterone acetate were added to prostate specific antigen expressing, androgen dependent LNCaP and androgen independent C4-2 cell line (Urocor, Oklahoma City, Oklahoma) cultures. Proliferation was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide assay (Roche, Mannheim, Germany). Prostate specific antigen mRNA expression was assessed by quantitative real-time polymerase chain reaction. Secreted prostate specific antigen protein levels were quantified by microparticle enzyme-immunoassay. RESULTS: Goserelin inhibited cell growth and prostate specific antigen protein secretion in LNCaP and C4-2 cells. Prostate specific antigen mRNA expression was not decreased. Bicalutamide did not affect cell growth or prostate specific antigen mRNA expression in LNCaP or C4-2 cells, although it significantly decreased prostate specific antigen protein secretion in LNCaP and to a lesser extent in C4-2 cells. Cyproterone acetate decreased the growth of C4-2 but not of LNCaP cells. It did not affect prostate specific antigen mRNA or protein expression in either cell line. CONCLUSIONS: Prostate specific antigen expression does not necessarily correlate with cell growth. Without a substantial effect on cell growth bicalutamide lowers prostate specific antigen synthesis, whereas cyproterone acetate decreases cell growth with no effect on prostate specific antigen secretion. Prostate specific antigen expression may be influenced by growth inhibition but also by altered mRNA and protein levels depending on the agent, its concentration and the cell line evaluated. For interpreting clinical trials prostate specific antigen is not necessarily a surrogate end point marker for a treatment effect on prostate cancer cell growth.     

Expression of gonadotropin-releasing hormone (GnRH) and GnRH receptor mRNA in prostate cancer cells and effect of GnRH on the proliferation of prostate cancer cells

The purpose of this study was to determine the production of gonadotropin-releasing hormone (GnRH), the co-occurrence of GnRH receptors in prostate cancer cells, and the effect of GnRH on prostate cancer cell proliferation. Four human prostate cancer cell lines were studied. LNCaP is an androgen sensitive prostate cancer cell line, DU-145 and PC-3 are androgen resistant, and TSU-Pr1 is uncharacterized. The expression of GnRH and GnRH receptor mRNAs were assessed by in situ hybridization and the effect of exogenous GnRH on proliferation of prostate cancer cells was measured by thymidine incorporation assay. GnRH mRNA expression, determined by in situ hybridization, was found in 83.48% of the LNCaP, 89.7% of the TSU-Pr1, 86.2% of the PC-3 and 95.3% of the DU-145. Signals of GnRH receptor mRNA were detected in more than 95% of the cells of all four cell lines. The proliferation of the prostate cancer cells grown in media supplemented with peptide hormone lacking charcoal-stripped serum was significantly (P < 0.05) suppressed. No significant effect of GnRH on the proliferation of all four prostate cancer cells was observed. In summary, prostate cancer cells produced GnRH and its receptors, and exogenous GnRH treatment did not affect the prostate cancer cell proliferation. The existence of GnRH and GnRH receptor mRNA in the same cell suggests that the role of GnRH produced by prostate cancer cells would be autocrine. Received: 21 August 1997 / Accepted 15 April 1998     

Chorioallantoic membrane assay: vascularized 3-dimensional cell culture system for human prostate cancer cells as an animal substitute model

PURPOSE: Chorioallantoic membranes have been used as a reliable biomedical assay system for many years. Chicken eggs in the early phase of breeding are between in vitro and in vivo systems but may provide an immunodeficient, vascularized test environment. We tested this model as an in vivo system for prostate cancer research. MATERIALS AND METHODS: Single cell suspensions of LNCaP, PC-3 and Tsu-Pr1 human prostatic cancer cell lines as well as 2 immortalized normal human prostate epithelial cell lines were inoculated on the chorioallantoic membrane of fertilized chicken eggs on day 5 or 6 of breeding. Tumor growth and viability of the embryo was evaluated by stereo microscopy. At day 10 the membranes were removed and embedded in paraffin. Cell morphology was assessed after hematoxylin and eosin staining. Cellular expression of cytokeratin, prostate specific antigen and androgen receptor as well as apoptosis induction was confirmed by immunohistochemistry. RESULTS: Three days after tumor cell inoculation on the extraembryonic vascular system of the chorioallantoic membrane cell growth and formation of 3-dimensional tumors became apparent in 100% of inoculated membranes. Strong neo-angiogenesis was detected next to the established tumors and tumor cells invading the stroma of the chorioallantoic membrane. Cytokeratin expression as well as prostate specific antigen and androgen receptor in LNCaP cells confirmed the human prostate tumor origin. Assessment of quantitative in vivo apoptosis induction in LNCaP cells after intravenous injection of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate confirmed the model as a versatile in vivo system. CONCLUSIONS: The well vascularized chorioallantoic membrane of bred chicken eggs is a suitable system for early in vivo cancer research. Reliable growth of prostate cancer cell lines is feasible and allows the evaluation of proliferation and apoptosis induction after intravascular or topic application of anticancer drugs. Exploitation of this assay enables a substantial reduction in or substitution for subsequent animal experiments.     

双氢睾酮和氟他胺干预前列腺癌细胞LNCaP线粒体内还原型谷胱甘肽的变化

目的 观察双氢睾酮(DHT)和氟他胺(FLU)作用于雄激素依赖性(LNCaP)前列腺癌细胞LNCaP线粒体自由基的变化,探讨DHT和FLU引起LNCaP细胞线粒体内还原型谷胱甘肽(GSH)变化的作用机制.方法 获得LNCaP细胞株,进行细胞培养,获得稳定生长及传代的细胞株.不同浓度的雄激素受体激动剂DHT及雄激素受体拮抗剂FLU作用于培养的LNCaP细胞株;不同时间点提取干预措施下的LNCaP细胞线粒体;通过检测并比较不同时间点、不同浓度药物作用下LNCaP细胞株线粒体自由基的变化和差异.结果 DHT作用于LNCaP细胞后,线粒体GSH的含量显著下降(P<0.05),各个指标在不同的时间点上下降的程度有所差异.FLU干预LNCaP后,中剂量组干预14 d与对照组比其GSH含量增加(P<0.05).其余各组GSH的含量差异无统计学意义(P>0.05).结论 DHT可明显降低LNCaP线粒体内GSH含量,说明可促进细胞的增殖活力;FLU不能清除LNCaP细胞线粒体GSH,导致自由基蓄积,可有效抑制LNCaP细胞的增殖.     

Androgen receptor-dependent regulation of Bcl-xL expression: Implication in prostate cancer progression

BACKGROUND: Recently we reported that silencing the androgen receptor (AR) gene reduced Bcl-xL expression that was associated with a profound apoptotic cell death in prostate cancer cells. In this study we further investigated AR-regulated Bcl-xL expression. METHODS: Prostate cancer cell line LNCaP and its sublines, LNCaP/PURO and LNCaP/Bclxl, were used for cell proliferation assay and xenograft experiments in nude mice. Luciferase gene reporters driven by mouse or human bcl-x gene promoter were used to determine androgen regulation of Bcl-xL expression. RT-PCR and Western blot assays were conducted to assess Bcl-xL gene expression. Chromatin immunoprecipitation assay was performed to determine AR interaction with Bcl-xL promoter. Bcl-xL-induced alteration of gene expression was examined using cDNA microarray assay. RESULTS: In cultured prostate cancer LNCaP cells, androgen treatment significantly increased Bcl-xL expression at mRNA and protein levels via an AR-dependent mechanism. Promoter analyses demonstrated that the AR mediated androgen-stimulated bcl-x promoter activation and that the AR interacted with bcl-x promoter. Enforced expression of Bcl-xL gene dramatically increased cell proliferation in vitro and promoted xenograft tumor growth in vivo. Genome-wide gene profiling analysis revealed that Bcl-xL expression was significantly higher in metastatic and castration-resistant diseases compared to normal prostate tissues or primary cancers. Bcl-xL overexpression significantly increased the expression of cyclin D2, which might be responsible for Bcl-xL-induced cell proliferation and tumor growth. CONCLUSIONS: Taken together, our data strongly suggest that androgen stimulates Bcl-xL expression via the AR and that increased Bcl-xL expression plays a versatile role in castration-resistant progression of prostate cancer.