Androgen receptor status in endocrine-paracrine cell types of the normal,hyperplastic, and neoplastic human prostate

Neuroendocrine differentiation is a frequent occurrence in common prostatic adenocarcinomas and may have prognostic implications in prostatic malignancies. In the present study, we used immunohistochemical double label methods to evaluate the nuclear androgen receptor (AR) status in endocrine-paracrine (EP) cells of normal, hyperplastic, and neoplastic prostate including tumours that recurred after hormonal and radiation therapy. In normal and hyperplastic glands, EP cells characterized by the panendocrine marker chromogranin A (Chr A) did not reveal AR-positivity. This may indicate that prostatic EP cells represent an androgen-indepenent cell population whose regulatory functions are not influenced by circulating androgens. Unequivocal co-expression of Chr A and AR was very rarely detected in subsets of endocrine differentiated tumour cells in treated and untreated specimens. The widespread absence of nuclear AR in neuroendocrine tumour cells suggests that this phenotype belongs to those cell clones in prostate cancer which are initially androgen-independent and refractory to hormonal therapy.This study was partially presented at the 82nd Annual Meeting of the United States and Canadian Academy of Patholoy, March 13–19, 1993.This study was supported by the Deutsche Forschungsgemeinschaft Bo-1018/1-5     

South Indian men with reduced CAG repeat length in the androgen receptor gene have an increased risk of prostate cancer

The androgen receptor (AR) gene possesses polymorphic CAG tandem repeats and the repeat length has been inversely related to the risk of prostate cancer (PCa). The distinct ethnic variation in the CAG repeat length may be correlated to differences in PCa risk in different populations. To evaluate the CAG repeat length in the AR gene and the implications for PCa, we screened 87 PCa patients and 120 control subjects from South India. The mean CAG repeat length in PCa patients was significantly smaller than that of controls (17.0 vs 20.7; P<0.001). Men with 19 CAG repeats had a significantly increased risk of cancer compared to those with >19 CAG repeats (age-adjusted OR=7.01; 95% CI=3.52–13.94; P<0.001). However, no significant association was observed between CAG repeats and age of onset or prostate-specific antigen levels. Although there was a trend towards shorter CAG repeat length in high grades of cancer, it was not significant (P=0.085). Thus, our results suggest an association between short CAG repeats in the AR gene and PCa risk in South Indian men. Further, we propose that CAG repeats could be used as a prognostic marker for PCa diagnosis.     

The androgen receptor: genetic considerations in the development and treatment of prostate cancer

The action of androgens in the development and growth of prostate carcinomas is well documented. The androgen receptor (AR) facilitates androgen-induced regulation of genes involved in cellular proliferation and differentiation. Since the early 1940s androgen ablation has been the cornerstone of treatment for metastatic prostate cancer. Although initially highly effective, hormonal therapy is not curative, and resistant disease will ultimately prevail. Mutations that alter AR conformation, function, and regulation may provide a selective growth advantage for subpopulations of cells within the tumor that are then able to proliferate in an androgen-deprived environment. Clinically, these mutations are important because they may lead to the growth of androgen-independent tumors and progression to a refractory state. Further characterization of AR mutations will lead to a more thorough understanding of their role in the development of prostate carcinomas. This information, in addition to discovering which genes are regulated by the AR, can aid in the future development of more effective pharmacotherapy for prostate cancer. Received: 2 November 1998 / Accepted: 8 February 1999     

Clostridium scindens metabolites trigger prostate cancer progression through androgen receptor signaling

Prostate cancer (PCa) is one of the most common malignancies in men; recently, PCa-related mortality has increased worldwide. Although androgen deprivation therapy (ADT) is the standard treatment for PCa, patients often develop aggressive castration-resistant PCa (CRPC), indicating the presence of an alternative source of androgen. Clostridium scindens is a member of the gut microbiota and can convert cortisol to 11β-hydroxyandrostenedione (11β-OHA), which is a potent androgen precursor. However, the effect of C. scindens on PCa progression has not been determined. In this study, androgen-dependent PCa cells (LNCaP) were employed to investigate whether C. scindens-derived metabolites activate androgen receptor (AR), which is a pivotal step in the development of PCa. Results showed that cortisol metabolites derived from C. scindens-conditioned medium promoted proliferation and enhanced migration of PCa cells. Furthermore, cells treated with these metabolites presented activated AR and stimulated AR-regulated genes. These findings reveal that C. scindens has the potential to promote PCa progression via the activation of AR signaling. Further studies on the gut–prostate axis may help unravel an alternative source of androgen that triggers CRPC exacerbation.     

Androgen receptor CAG and GGC polymorphisms in Mediterraneans: repeat dynamics and population relationships

Microsatellite variation (CAG and GGC repeats) of the androgen receptor (AR) gene shows remarkable differences among African and non-African populations. In vitro studies have demonstrated an inverse relationship between the length of both microsatellites and AR activity. This fact may explain the observed association of the AR gene with prostate cancer and the strong ethnic differences in the incidence of this cancer. CAG and GGC genetic variation has been tested in a large set of populations from the Ivory Coast as well as 12 Mediterranean samples whose variation is described for the first time. The pattern of frequencies observed in the Ivory Coast agrees with data previously reported for other Sub-Saharan populations. Concerning the Mediterranean variation, Sardinian samples are characterised by low genetic diversities, and Egyptian Siwa Berbers by a particular pattern of GGC frequencies. High and Middle Atlas Moroccan Berbers are the most closely related to the Sub-Saharan variation. For both the CAG and GGC repeats, the Ivory Coast and some Moroccan samples exhibit high frequencies of low size alleles (CAG under 18 repeats, and GGC under 15 repeats) that have been associated with prostate cancer.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users     

c-myc amplification is associated with HER2 amplification and closely linked with cell proliferation in tissue microarray of nonselected breast cancers

C-myc and HER2 amplification were analyzed on 214 consecutive breast cancers by fluorescence in situ hybridization using tissue microarray technology. The frequencies of amplification were 15.4% (33/214) and 23.3% (49/210), respectively. c- myc amplification was significantly associated with HER2 amplification ( P < .001) and closely linked with cell proliferative activity, measured by Ki67 labeling index ( P = .010). In univariate survival analysis, lymph node status, tumor size, and histological grade were significant prognostic factors, but in multivariate analysis, lymph node status was the only significant factor. Patient survival did not differ according to c- myc amplification status, and c- myc amplification showed no significant correlation with clinicopathologic features of the tumors. A strong correlation between c- myc and HER2 amplification and proliferative activity indicates a biological link between these genes in breast cancer cell.     

GGN repeat length and GGN/CAG haplotype variations in the androgen receptor gene and prostate cancer risk in south Indian men

The ethnic variation in the GGN and CAG microsatellites of the androgen receptor (AR) gene suggests their role in the substantial racial difference in prostate cancer risk. Hence, we performed a case-control study to assess whether GGN repeats independently or in combination with CAG repeats were associated with prostate cancer risk in South Indian men. The repeat lengths of the AR gene determined by Gene scan analysis, revealed that men with GGN repeats ≤21 had no significant risk compared to those with >21 repeats (OR 0.91 at 95% CI-0.52–1.58). However, when CAG repeats of our earlier study was combined with the GGN repeat data, the cases exhibited significantly higher frequency of the haplotypes CAG ≤19/GGN ≤21 (OR-5.2 at 95% CI-2.17–12.48, P < 0.001) and CAG ≤19/GGN > 21(OR-6.9 at 95%CI-2.85–17.01, P < 0.001) compared to the controls. No significant association was observed between GGN repeats and prostate-specific antigen levels and the age at diagnosis. Although a trend of short GGN repeats length in high-grade was observed, it was not significant (P = 0.09). Overall, our data reveals that specific GGN/CAG haplotypes (CAG ≤19/GGN ≤21 and CAG ≤19/GGN > 21) of AR gene increase the risk of prostate cancer and thus could serve as susceptibility marker for prostate cancer in South Indian men.     

基因扩增在肺癌中的研究进展

原癌基因的激活是包括肺癌在内的众多恶性肿瘤的重要特征,而原癌基因发生扩增被认为在原癌基因激活过程中起着重要作用.随着分子遗传学技术的发展,人们在实体瘤中发现越来越多的原癌基因存在着扩增现象,因此了解基因扩增可以为肿瘤早期诊断或治疗提供新的有效的靶点.本文综述了目前肺癌中基因扩增的研究进展.     

毒蕈碱胆碱能受体3在小细胞肺癌增殖和迁移中的调节作用

目的:研究毒蕈碱胆碱能受体3(M3R)在人小细胞肺癌(SCLC)中的表达及其作用。方法:体外培养人SCLC细胞株SBC3和H82,RT-PCR和Western blotting法检测M3R的表达,MTT法和Boyden chamber法分别检测胆碱受体激动剂碘化乙酰胆碱(ACh)及M3R拮抗剂4-diphenylacetoxy-N-methylpiperidine methiodide(4-DAMP)对SBC3细胞增殖和迁移的影响。结果:SBC3和H82细胞均表达M3R,SBC3细胞M3R蛋白相对表达强度是H82细胞的2.65倍。ACh浓度依赖性地刺激SBC3细胞增殖,10-4和10-3mol/L ACh在48h和72h作用明显(P0.01)。4-DAMP浓度依赖性地阻断ACh对细胞增殖的刺激作用,48h时,10-5mol/L4-DAMP阻断ACh的作用(P0.05),至72h,10-7、10-6mol/L(P0.05)和10-5mol/L(P0.01)4-DAMP都能阻断ACh的作用。无外源性ACh的情况下,10-6、10-5mol/L4-DAMP在48h都能明显地抑制细胞增殖(P0.01),在72h,10-5mol/L4-DAMP的作用(P0.01)强于10-6mol/L4-DAMP(P0.05)。ACh浓度依赖性地增强SBC3细胞向人纤维结合蛋白(Fn)的迁移,10-4mol/L ACh增加细胞迁移约3倍,10-6、10-5mol/L4-DAMP几乎完全阻断10-4mol/LACh刺激的SBC3细胞迁移(P0.01)。结论:人SCLC细胞表达M3R,M3R拮抗剂抑制SCLC细胞增殖和迁移。     

Cullin-1 promotes cell proliferation via cell cycle regulation and is a novel in prostate cancer

Background: There is no reliable marker available for early detection, diagnostic confirmation, or disease prognosis available of prostate cancer (PCa). We aimed to evaluate the function of Cullin-1 and unravel its underlying molecular mechanism to develop novel treatment options equivalent to PCa. Method: We used immunohistochemistry to analyze the correlation between Cullin-1 expression and clinicopathologic variables and patient survival. The Cullin-1 level was tested in PCa cells. The role of regulation of Cullin-1 in PCa was applied in vitro and vivo. In addition, we further investigated the signaling pathway of Cullin-1 in prostate cancer cell proliferation. Result: We first discovered that Cullin-1 expression was upregulated in human PCa tissues and inversely related with PCa differentiation. We then found that high expression of Cullin-1 protein suggested a poor prognosis in PCa patients. Also, Cullin-1 promotes PCa cell proliferation in vitro and tumor growth in vivo. We then found that the mechanism of Cullin-1 regulation on cell-cycle progression is due to increased expression of p21 and p27, and decreased expression of cyclin D1 and cyclin E after Cullin-1 knockdown. Conclusion: Cullin-1 exerts multiple biological effects in the PCa cell line. Through promoting proliferation and by countering cisplatin-induced apoptosis, Cullin-1 has been deeply implicated in the pathogenesis and development of PCa.     

4株乳腺癌细胞中内皮素受体B基因的甲基化状态及对MCF-7细胞增殖的影响

目的 探讨内皮素受体B（EDNRB）基因在4株乳腺癌细胞中的表达、甲基化状态以及恢复EDNRB表达对MCF-7细胞增殖的影响。 方法 采用甲基化特异性PCR（MS-PCR）和亚硫酸盐测序法（BSP）分析4株乳腺癌细胞中EDNRB的甲基化状态;反转录聚合酶链反应（RT-PCR）检测EDNRB mRNA的表达水平;采用四甲基偶氮唑蓝（MTT）法和集落形成实验检测EDNRB表达恢复对MCF-7细胞增殖的影响。 结果 EDNRB在乳腺癌细胞MCF-7和ZR-75-1中表达缺失,并呈高甲基化状态;而在EDNRB表达最高的MDA-MB-231细胞中其启动子呈低甲基化,表明乳腺癌细胞中EDNRB基因启动子甲基化状态与其表达成负相关。5-氮杂胞苷（5-Aza-CR）能够反转EDNRB基因的表达,EDNRB表达恢复后MCF-7细胞的增殖受到抑制。 结论 EDNRB基因启动子区CpG岛频繁甲基化可能在乳腺癌发生发展中发挥重要作用,EDNRB有望成为乳腺癌早期诊断的新的分子标志物。     

HER2 expression and gene amplification in pT2a Gleason score 6 prostate cancer incidentally detected in cystoprostatectomies: comparison with clinically detected androgen-dependent and androgen-independent cancer

Previous studies have demonstrated HER2 protein overexpression and/or gene amplification in a subset of patients with clinically significant prostate cancer (PCa), especially in the androgen-independent phase of the disease. There are no studies on incidentally detected PCa. The aim of the study was to analyze HER2 expression and gene amplification in PCa incidentally detected in cystoprostatectomies. High-grade prostatic intraepithelial neoplasia (HGPIN) was also investigated. Comparison was made with clinically detected PCa, both untreated and hormonally treated, and with androgen-independent PCa. Nineteen cystoprostatectomy (CyP) and 44 radical prostatectomy specimens (25 untreated and 19 hormonally treated) with pT2a Gleason score 6 cancer and HGPIN were used in this study. It also included 9 specimens of transurethral resection of the prostate with hormone-independent cancer and 8 cases of normal prostate tissue from CyP specimens without PCa and prostatic intraepithelial neoplasia. HER2 protein and Ki-67 were investigated immunohistochemically. Patients with immunohistochemical scores of 2+ and 3+ were considered to have HER2 overexpression (HercepTest method). Dual-color fluorescence in situ hybridization analysis was performed using the CEP-17/HER dual probe combination. High-grade prostatic intraepithelial neoplasia showed HER2 overexpression in 26% of the CyP cases and in 40% and 83% of the untreated and treated cases, respectively. Prostate cancer showed HER2 overexpression in 16% of cases in the CyP group and in 36% and 47.5% in the untreated and treated groups, respectively. HER2 overexpression was present in 78% of androgen-independent cancers. HER2 gene amplification was seen in a small proportion of nuclei and some of the cases. In HGPIN, it ranged from 1.1% (in 5 cases) in the CyP group to 2.1% (in 10 cases) and 1.9% (in 6 cases) in the untreated and treated groups, respectively. In PCa, the proportion of nuclei with gene amplification was 0.7% (in 3 cases) in the CyP group, 2.6% (in 10 cases) and 2.5% (in 12 cases) in the untreated and treated groups, respectively, and 9% (in 6 cases) in the androgen-independent PCa. Ki-67 expression in HGPIN and PCa in CyP specimens was lower than in the radical prostatectomies and cases of transurethral resection of the prostate. Our findings in the current HER2-related study indicate that incidentally detected cancer has features of less aggressiveness than clinically detected cancer. This may contribute to a better understanding of the results obtained in screening programs where insignificant cancers are detected along with clinically significant cancers.     

Androgen receptor expression is usually maintained in initial surgically resected breast cancer metastases but is often lost in end-stage metastases found at autopsy

Androgen receptor (AR) is expressed in approximately 70% of primary breast carcinomas (PBCs) and is a promising therapeutic target for metastatic breast carcinoma (MBC). Here, we examine AR expression in a population of initial surgically resected metastases and a separate cohort of end-stage metastases harvested at autopsy compared with their matched PBCs. Tissue microarrays of matched PBC and MBC were labeled by immunohistochemistry for AR, estrogen receptor (ER), progesterone receptor (PR), and Her2 and classified into the following previously described categories: luminal (ER/PR+/Her2-), triple negative (ER/PR/Her2-), Her2 (ER/PR-/Her2+), and luminal loss (ER/PR loss from primary to metastasis). In the cohort of surgically resected metastases (n = 16), AR was expressed in 12 of 16 PBC and maintained in 11 of 12 corresponding MBCs. Of these, 36% showed stronger AR labeling in the metastases and none showed a decrease. In the cohort of metastases harvested at autopsy (n = 16), AR was expressed in 11 of 16 primary carcinomas and maintained in only 5 of 11 corresponding metastases. Of these, none showed increased AR and 80% showed decreased AR labeling. AR expression is overwhelmingly concordant between matched PBC and MBC at initial presentation. These findings validate AR as a therapeutic target in MBC and suggest that AR may need to be reevaluated in metastases even if the primary is negative. However, similar to ER/PR, AR expression is often decreased with a trend toward complete loss in end-stage metastases, suggesting a shift of AR expression between initial and end-stage metastases. This suggests an opportunity for targeted antiandrogen therapy at an earlier stage of disease progression.     

AR-V7在前列腺癌细胞耐药中的作用

目的:探讨雄激素受体剪接变异体7(AR-V7)在前列腺癌细胞耐药中的作用及分子机制。方法:运用Lipofectamine2000转染法将AR-V7 siRNA(siAR-V7)转染至4株前列腺癌细胞中,命名为PC3-siAR-V7、DU145-siAR-V7、LNCaP-siAR-V7和ArCaP-siAR-V7细胞,以转染无关序列(NC siRNA)为阴性对照。运用real-timePCR和Westernblot实验分别检测转染前后细胞中AR-V7的mRNA和蛋白表达水平;运用MTT法和Transwell法分别检测细胞活力和细胞迁移率;运用萤光素酶报告基因实验和Western blot实验分别检测AR的启动子活性及下游靶基因前列腺特异性抗原(PSA)和FK506结合蛋白5(FKBP5)的蛋白表达。构建耐比卡鲁胺的前列腺癌细胞系LNCaP-DR,运用免疫荧光观察LNCaP、LNCaP-siAR-V7和LNCaP-DR细胞中AR和AR-V7的亚细胞定位;运用蛋白质免疫共沉淀实验检测AR-V7与热休克蛋白90(HSP90)的相互作用。结果:4株前列腺癌细胞中的AR-V7 mRNA水平显著高于正常前列腺上皮细胞RWPE-1(P0.05);PC3-siAR-V7、DU145-siAR-V7、LNCaP-siAR-V7和ArCaPsiAR-V7细胞中AR-V7蛋白水平、细胞活性及细胞迁移率显著低于NCsiRNA转染的细胞(P0.05)。随着比卡鲁胺剂量的增加,所有细胞活力逐渐降低,而下调AR-V7表达显著增强前列腺癌细胞对比卡鲁胺的敏感性(P0.05)。Westernblot结果显示下调AR-V7表达显著抑制AR启动子活性,其下游PSA和FKBP5蛋白水平明显降低(P0.05)。免疫荧光结果发现AR和AR-V7主要存在于前列腺癌细胞核内,AR少量存在于细胞质中;下调AR-V7表达则抑制AR的核转运;AR存在于耐药细胞核中,AR-V7在耐药细胞中高表达。免疫共沉淀结果显示内源性AR-V7与HSP90相互作用。结论:AR-V7在前列腺癌细胞中高表达,下调AR-V7的表达显著抑制前列腺癌细胞活力和迁移;前列腺癌细胞耐药与AR-V7高表达相关,其机制可能通过AR-V7与HSP90相互作用介导AR-V7的核转运,激活AR信号通路调控下游靶基因的转录活性最终导致细胞耐药。     

胰岛素受体亚型改变及相关通路活化在糖尿病小鼠肠上皮细胞过度增殖中的作用

 目的:探讨胰岛素受体亚型改变及其相关下游通路活化情况在糖尿病小鼠肠上皮细胞异常增殖中的作用。方法:用腹腔注射链脲霉素的方法制作糖尿病小鼠模型,采用增殖细胞核抗原标记法比较糖尿病小鼠及对照组小鼠肠上皮细胞的增殖情况。利用RT-PCR法测定胰岛素受体亚型表达比例在2组中的差异。采用real-time PCR及Western blot法分别从mRNA和蛋白质水平检测2组之间胰岛素受体相关通路各分子MEK1/2、ERK1/2、PI3K以及Akt的表达情况。结果:糖尿病组小鼠的小肠上皮细胞增殖指数显著升高(P<0.05),且细胞中胰岛素受体亚型IR-A/IR-B的比值也明显升高(P<0.05)。糖尿病小鼠肠上皮细胞中MEK1、MEK2和ERK1/2的mRNA水平及磷酸化蛋白水平均高于对照组(P<0.05)。结论:糖尿病小鼠肠上皮细胞过度增殖可能与其中胰岛素受体亚型IR-A/IR-B的比值增高及其相关MEK/ERK通路的激活有关。     

转染CRKL蛋白对肺癌细胞系增殖的研究

目的研究CRKL蛋白对肺癌细胞系增殖的影响及其可能机制,探讨CRKL基因在肺癌发病中的作用。方法在转染CRKL的HBE和H1299两种肺癌细胞系中,采用Western blot,流式细胞技术(FCM),集落形成实验和MTT方法检测转染CRKL后,对肺癌细胞增殖的影响。结果转染CRKL基因后,可明显上调Cyclin D1和Cyclin B蛋白在HBE和H1299两种肺癌细胞表达,增加Rb的磷酸化,促进肺癌细胞的增殖、克隆形成能力。结论 CRKL通过调节细胞周期促进肺癌细胞的增殖能力,CRKL可作为非小细胞肺癌的标记物,并可能成为治疗该肿瘤的新靶点。     

西乐葆对雄激素剥夺治疗的前列腺癌患者血清PSA的影响

目的：初步评价选择性环氧合酶-2（COX-2）抑制剂西乐葆对雄激素剥夺治疗（AAT）前列腺癌（Pca）患者血清前列腺特异抗原（PSA）的影响.方法：对33例接受AAT后PSA升高的Pca患者口服西乐葆0.4 g/d,治疗3、6个月时随访血清tPSA、fPSA和f/tPSA,通过比较治疗前后PSA倍增时间（PSADT）、fPSA和f/tPSA的变化,评价西乐葆对AAT患者PSA的影响.结果：西乐葆治疗前,高PSADT 18例（54.5%）,无一例出现tPSA下降;治疗后3、6月时, PSADT延长、血清tPSA下降例数分别为13、10;与治疗前相比,治疗后3、6个月时PSADT、fPSA、f/tPSA差异具有统计学意义（P＜0.05）.结论：选择性COX-2抑制剂西乐葆可降低血清PSA增加速率,对AAT前列腺癌患者产生良好的疗效.