Prostasin基因在前列腺细胞株中表达情况研究

目的 探讨Prostasin在前列腺癌中的功能。方法 运用RT-PCR方法检测人前列腺增生细胞株BPH-1，无转移能力前列腺癌细胞株LNCaP，及有转移能力的前列腺癌细胞株PC-3、DU-145中Prostasin基闪表达情况。结果 Prostasin基斟在BPH-l和LNCaP中正常表达，在PC-3、DU-145中低表达。BPH-l中Prostasin的表达与DU-145和PC-3比较差异有显著性，同样LNCaP中Prostasin的表达与DU-145和PC-3比较差异亦有显著性（P〈0．01）。BPH-1与LNCaP之间表达差异无显著性，DU-145和PC-3之间表达差异亦无显著性，（P〉0.05）。结论 ProStasin可能是前列腺癌的转移抑制剂。     

不同前列腺癌细胞株Talin-1表达情况和侵袭能力关系研究

目的探讨踝蛋白1(Talin-1)在不同前列腺癌细胞株中的表达情况和侵袭能力的关系。方法体外培养不同人前列腺癌细胞株(DU-145、PC-3、LNCaP)及人正常前列腺上皮细胞株(RWPE-1)。传代培养后利用MTT法检测各细胞株增殖能力。细胞划痕实验,Transwell小室侵袭和迁移实验检测各细胞株侵袭及迁移能力。RT-PCR技术检测各细胞株中Talin-1的mRNA表达水平。Western-blot技术检测各细胞株中Talin-1的蛋白表达水平。结果与RWPE-1细胞株相比,LNCaP细胞株、PC-3细胞株、DU145细胞株的增殖、侵袭和迁移能力明显增高(P0.05),其中LNCaP、PC-3、DU-145细胞株的增殖、迁移以及侵袭能力依次递增(P0.05)。前列腺癌LNCaP细胞株、PC-3细胞株、DU145细胞株中的Talin-1 mRNA及蛋白表达水平显著高于RWPE-1细胞株(P0.05);其中LNCaP、PC-3、DU-145细胞株中的Talin-1 mRNA以及蛋白表达水平依次递增(P0.05)。结论Talin-1与前列腺癌的增殖、侵袭和迁移能力相关;低表达Talin-1的前列腺癌的增殖、侵袭和迁移能力低,恶性度低;高表达Talin-1的前列腺癌的增殖、侵袭和迁移能力强,恶性度高。Talin-1可作为前列腺癌恶性度的预测指标之一。     

膜联蛋白A2和葡萄糖调节蛋白78表达与前列腺癌的关系

目的 分析膜联蛋白A2(Annexin A2)和葡萄糖调节蛋白78(GRP78)分别在人前列腺增生细胞系(BPH-1)、雄激素非依赖性前列腺癌细胞系(LNCaP)和雄激素依赖性前列腺癌细胞系(PC-3)中的差异表达. 方法 利用双向凝胶电泳结合质谱的蛋白质组学技术,分析Annexin A2和GRP78在三种细胞系的表达;分别采用免疫印迹法和免疫荧光染色法对其进行半定量和定位验证. 结果 Annexin A2在BPH-1和LNCaP中低表达,在PC-3细胞中高表达;GRP78在PC-3、BPH-1及LNCaP中表达量逐渐升高(P＜0.05). 结论 Annexin A2和GRP78的差异表达可能与前列腺癌发展的不同阶段激素依赖性有关,有望作为前列腺癌诊断和治疗的重要指标.     

前列腺癌与良性前列腺增生细胞株差异核基质蛋白的鉴定

目的:鉴定人前列腺癌雄激素依赖性细胞株LNCaP、前列腺癌雄激素非依赖性细胞株PC-3与良性前列腺增生细胞株BPH-1之间差异表达的核基质蛋白(nuclear matrix proteins,NMPs)。方法:常规制备各细胞株NMPs,应用双向凝胶电泳对其进行分离;对差异表达的蛋白质点行MALDI-TOF-MS/MS质谱分析,数据库搜索并鉴定。结果:成功获得了分辨率高、重复性好的不同细胞株NMPs双向凝胶电泳图谱;初步鉴定出包含酶、调节蛋白、RNA结合蛋白及各种因子在内的12个差异表达的蛋白质,在癌细胞株中3个NMPs表达上调,9个下调。结论:人前列腺癌细胞与良性前列腺增生细胞之间NMPs表达存在明显差异;初步筛选出12个差异NMPs,其表达水平及功能与疾病的联系需进一步研究。     

非甾体类抗炎药NS398对前列腺癌细胞株DU145中RECK基因表达的调控

目的:通过检测非甾体类抗炎药NS398对前列腺癌细胞株DU145中RECK基因表达的调控,探讨其可能的抗肿瘤机制。方法:实验组(3组)分别以不同浓度(10、100、1000μmol/L)NS398作用于前列腺癌细胞株DU145,而对照组则无NS398,各组均培养48h后收集细胞,抽取各组细胞总RNA,检测RECK基因与MMP9的表达;抽取各组细胞总蛋白,应用Western印迹方法检测RECK蛋白的表达。结果:实验组细胞株中RECK基因表达均较对照组明显升高,其中以100μmol/L组升高最明显,而MMP9的含量明显降低;实验组RECK蛋白的表达也较对照组明显升高(P<0.05)。结论:NS398有明显的诱导RECK基因表达的作用,是其可能的抗肿瘤作用机制。     

TGF-β/Smads通路关键蛋白在5种前列腺癌细胞株中表达的鉴定及意义

目的:对多种不同人前列腺癌细胞株TGF-β/Smads信号通路的"开放"或"关闭"状态进行鉴定,初步探讨此通路在前列腺癌侵袭、转移中的作用及可能的机制。方法:用Western印迹法检测LNCaP、PC-3、DU145及AR-CaP亚细胞系IF11、IA8细胞中TGF-β/Smads通路的关键蛋白TGF-βⅡ型受体(TβRⅡ)、Smad2/3、磷酸化Smad2(p-Smad2)、Smad4的差异表达。结果:TβRⅡ在PC-3、DU145、IF11、IA8中表达较高,在LNCaP中表达极低;Smad2/3在所有细胞中表达均较高,但活性成分p-Smad2仅在PC-3、DU145中表达;Smad4在LNCaP、PC-3、DU145中表达较高,IF11、IA8中表达缺失。结论:不同转移潜能的前列腺癌细胞株TGF-β/Smads通路的"开闭"状态存在差异,仅PC-3、DU145细胞处于开放状态;前列腺癌细胞可能通过不同的方式改变TGF-β/Smads通路状态参与晚期肿瘤的侵袭、转移过程。     

mitofusin-2对乳腺癌细胞RECK基因表达及MMPs活性的影响

目的 探讨线粒体融合素基因-2(mitofusin-2)对乳腺癌MCF-7细胞株中RECK表达及MMP-9,MMP-2活性的影响.方法 利用脂质体lipofectamine2000将构建的重组真核表达质粒pEGFPmfn2转染MCF-7细胞.RT-PCR检测细胞mfn2和RECK基因mRNA的转录水平;Weastem Blot法检测mfn2及RECK蛋白的表达;明胶酶谱试验检测转染前后MMP-9及MMP-2的活性.结果 转染pEGFP-mfn2质粒的MCF-7细胞可以稳定高表达Mfn2;RECK基因在转染空质粒组和未转染组细胞中无表达;转染mfn2基因后RECK基因mRNA转录及蛋白的表达显著升高,且MMP-9及MMP-2的活性显著降-低(P＜0.05).结论 mfn2基因可激活MCF-7细胞中RECK基因的表达,并显著抑制其MMP-9及MMP2的活性.该途径可能是mfn2基因抗肿瘤作用的新机制.     

非甾体类抗炎药NS398对前列腺癌动物模型中RECK基因表达的调控

目的:通过检测非甾体类抗炎药NS398对前列腺癌动物模型中RECK基因表达的调控,探讨其可能的抗肿瘤机制。方法:成瘤裸鼠分为实验组和对照组,实验组裸鼠予口咽管下喂服NS398,每天剂量0.1 mg/g体重,分别喂服10 d、20 d、30 d,对照组不予喂药,各组均在30 d后处死裸鼠;抽提各组肿瘤组织总RNA,RT-PCR检测RECK基因与MMP-9的表达;抽提各组肿瘤组织总蛋白,应用W estern印迹法检测RECK蛋白的表达。结果:实验组肿瘤组织中RECK基因的表达量较对照组明显升高,而MMP-9的表达量明显降低,且其变化与用药时间有明显的相关性。结论:NS398对前列腺癌的发生及转移有明显的抑制作用,其具体的作用机制可能与其诱导RECK基因的表达,从而抑制MMP-9的表达有关。     

精子发生相关基因SOX30基因在人前列腺癌组织中的表达及其临床意义

目的研究SRY box containing gene 30(SOX30)基因在前列腺癌组织中表达情况,并且分析SOX30的表达与前列腺癌临床病理特征之间的相关性;并检测SOX30在前列腺癌细胞PC3、DU145、LNCaP以及正常人前列腺上皮细胞RWPE-1中的表达情况。方法采用免疫组织化学方法检测SOX30在前列腺癌组织中表达特点,采用逆转录实时定量聚合酶链式反应(RT-qPCR)和蛋白印迹法(Western Blotting)分析SOX30在PC3、DU145、LNCaP以及正常人前列腺上皮细胞RWPE-1中的表达情况,运用统计学方法分析SOX30蛋白表达量与前列腺癌临床病理特征之间的关系。结果在123例前列腺癌中,68例(55.28%)发生SOX30表达缺失,并且SOX30表达缺失与前列腺分期(P=0.001)、Gleason评分(P0.001)有明显的相关性;与正常人前列腺上皮细胞RWPE-1相比,SOX30在PC3、DU145、LNCaP中表达明显降低。结论 SOX30可能是作为一个肿瘤抑制基因在前列腺癌的发生发展中起着重要作用。     

靶向沉默核干因子对前列腺癌PC-3细胞增殖能力的影响

目的:检测前列腺癌PC-3、LNCaP及DU145细胞中核干因子(Nucleostemin,NS)基因的表达,研究NS基因沉默后对PC-3细胞增殖能力的影响。方法:采用免疫细胞化学法及逆转录-聚合酶链反应(RT-PCR)分别检测NS蛋白及mRNA在3种前列腺癌细胞中的表达。用NS特异性小发夹RNA表达质粒转染PC-3细胞,分别用RT-PCR及Western印迹方法检测转染后细胞(简称NS-shRNA-PC-3)中NSmRNA及蛋白的变化。比较NS基因沉默前后PC-3细胞体外、裸鼠体内增殖能力及凋亡情况的变化。结果:3种细胞中均显示NS基因高表达。转染后NS-shRNA-PC-3细胞中NS表达显著降低,细胞增殖速度减慢,G0/G1期细胞百分率显著升高,早期凋亡细胞增多。体内致瘤实验显示,NS基因沉默后,PC-3细胞在裸鼠体内增殖能力显著降低。结论:NS在前列腺癌细胞系中呈高表达,RNA干扰沉默NS基因后PC-3细胞增殖能力显著降低,凋亡细胞增多。     

凋亡抑制基因XIAP在前列腺癌细胞中的表达及与临床病理特征的关系

目的 :研究XIAP基因在前列腺癌细胞系和前列腺癌组织的表达情况 ,及其与前列腺癌临床病理特征的关系。　方法 :应用RT PCR检测前列腺癌组织、正常前列腺组织和前列腺癌细胞株PC 3,DU 14 5 ,LNCaP细胞XIAP基因的表达 ,并通过免疫组化SP法检测 5 6例前列腺癌组织标本XIAP蛋白的表达情况。　结果 :XIAP基因在前列腺癌组织和前列腺癌细胞株PC 3,DU 14 5 ,LNCaP细胞高表达 ,正常前列腺组织无表达。在前列腺癌组织和癌旁组织中 ,XIAP蛋白阳性检出率分别为 5 3.6 % (30 / 5 6 )和 2 1.5 % (12 / 5 6 ) (P <0 .0 1) ;不同分期、分级组XIAP阳性检出率相比差异无显著性 (P >0 .0 5 )。　结论 :凋亡抑制基因XIAP与前列腺癌相关 ,在前列腺癌发生过程中具有重要的作用 ,有可能成为前列腺癌治疗的靶标。     

Antitumor activity of the histone deacetylase inhibitor MS-275 in prostate cancer models

BACKGROUND: Histone deacetylase (HDAC) inhibitors represent a novel class of therapeutic agents with antitumor activity currently in clinical development. In this study, we tested the biological effects of the HDAC inhibitor MS-275 in various pre-clinical prostate cancer models both in'vitro and in vivo. METHODS: In vitro cell proliferation XTT assay and protein expression analysis by Western blot were performed. In vivo tumor growth assessment in subcutaneous, orthotopic, and transgenic mouse models were conducted. RESULTS: MS-275 significantly upregulated histone H3 acetylation and p21 gene expression in human prostate cancer cell lines. MS-275 exerted growth arrest in PC-3 and LNCaP cells, and induced cell death in DU-145 cells. Prostate specific antigen protein levels were increased by MS-275 in LAPC4 cell line. In vivo, MS-275 inhibited the growth of DU-145, LNCaP, and PC-3 in subcutaneous xenografts. MS-275 had also a significant inhibition of PC-3 cells growth in a mouse intratibial model. Molecular analysis showed increased histone acetylation and p21 expression in tumor samples from MS-275-treated mice. In transgenic adenocarcinoma of mouse prostate (TRAMP) mice, long-term treatment of MS-275 slowed the progression of prostate carcinomas with significant reduction in cell proliferation. CONCLUSIONS: Taken together, these data support the clinical testing of MS-275 for the treatment of prostate cancer.     

mRNA expression of the five membrane-type matrix metalloproteinases MT1-MT5 in human prostatic cell lines and their down-regulation in human malignant prostatic tissue

BACKGROUND: The aim of this study was to assess the expression of membrane-type matrix metalloproteinases (MT-MMPs) 1-5 in the human prostatic cell lines BPH-1, LNCaP, DU 145, PC-3, in malignant and non-malignant prostatic tissue samples, and in epithelial cells cultured from these tissue samples. METHODS: Matched malignant and non-malignant tissue specimens were obtained from 12 men with untreated prostate carcinoma after radical prostatectomy. Expression of mRNA for the five MT-MMPs was quantified by real-time PCR technique and normalized to the expression of the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH). RESULTS: The expression of the five MT-MMPs was distinctly different not only between the prostate cell lines but also varied in the same cell line. There was a general higher expression of all MT-MMPs except for MT3-MMP in the androgen-insensitive cells DU 145 and PC-3 compared with that in the androgen-sensitive LNCaP cells. Their relatively high expression in the benign prostatic cell line BPH-1 and also in the primary cell cultures from malignant and non-malignant tissue samples argues against a simple association between MT-MMP expression and invasiveness. In malignant tissue samples and their corresponding cell cultures, the expression of most MT-MMPs was down-regulated in comparison to the normal counterparts. There was no correlation between tumor classification data and the MT-MMP expression results. CONCLUSIONS: In contrast to other carcinoma, the down-regulation of most MT-MMPs is typical for prostate carcinoma. It seems to occur mainly in epithelial cells and has to be examined as special characteristic of this tumor entity in further studies.     

Amplification of MMP-2 and MMP-9 production by prostate cancer cell lines via activation of protease-activated receptors

BACKGROUND: The matrix metalloproteinases (MMP) are a family of proteolytic enzymes involved in facilitating cancer metastasis. Protease-activated receptors (PARs) have previously been shown to be involved in pathways of MMP upregulation by tumor cells. METHODS: Two androgen independent prostate cancer cell lines, PC3 and DU-145, and one androgen dependent prostate cancer line LNCaP, were investigated. PAR expression was detected using RT-PCR and immunofluorochemistry (IFC) techniques. MMP activity assays were used to quantify the levels of MMP-2 and -9 on all three prostate cell lines after PAR activation. RESULTS: RT-PCR and IFC showed the presence of PAR-1 and PAR-2 in all cell lines investigated, only LNCaP showed PAR-3 and PAR-4 expression. Increased levels of MMP-2 and MMP-9 activity, up to sevenfold depending on prostate cancer cell line, following PAR activation by specific PAR peptides was shown. CONCLUSION: Preliminary studies show the activation of PAR-1 or PAR-2 produced increased levels of MMP-2 and MMP-9 activity in prostate cancer cell lines, indicating their potential role in the metastasis of prostate cancer cells.     

Down-regulation of macrophage inhibitory cytokine-1/prostate derived factor in benign prostatic hyperplasia

BACKGROUND: Macrophage inhibitory cytokine-1 (MIC-1) is a member of transforming growth factor-beta/bone morphogenetic protein (BMP) superfamily. Despite its potential role in prostatic regulation, little is known about its biological activity. METHODS: Expression profiling using 42K Affymetrix HuGeneFL array was conducted to compare symptomatic benign prostatatic hyperplasia (BPH), histological BPH without symptoms, and normal prostate samples from donors. MIC-1 gene expression was analyzed by RT-PCR in pure culture of prostate epithelial and stromal cells, and prostate cancer cells, LNCaP, PC-3, DU-145. Influence of androgens on MIC-1 expression in LNCaP cells was analyzed by Northern blot. Enhancement of promoter activity of MIC-1 by androgens was examined using reporter assays. RESULTS: In contrast to normal prostates, MIC-1 gene was down-regulated in BPH samples with symptoms and histological BPH obtained from cystoprostatectomy specimens (P < 0.005 and P < 0.01, respectively). Expression level of MIC-1 in androgen-sensitive LNCaP cells was high and enhanced by androgens, whereas in the androgen-insensitive PC-3 and DU-145 cells the expression level was low. An 11 kb promoter region of MIC-1 gene was identified to be 6- to 12-fold activated by androgens. CONCLUSIONS: Down-regulation of MIC-1 may play a role in the development of BPH. MIC-1 is positively regulated by androgens, but other regulatory factors remain unclear.     

Phenotypic and genotypic characterization of commonly used human prostatic cell lines

OBJECTIVE: To investigate and catalogue systematically the phenotypic and genotypic characteristics of the commonly used prostatic cell lines using immunocytochemistry and polymerase chain reaction (PCR) of hypervariable sequences within the genome to provide a 'fingerprint' characteristic of each cell line. Materials and methods Malignant (LNCaP, LNCaP-r, PC-3, DU-145) and benign immortalized prostatic cell lines (PNT-1A, PNT-1B, BPH-1) were grown on four-well slides, fixed and subjected to indirect streptavidin-biotin immunocytochemistry. Twenty-three antibodies were used in the following groups: cytoskeletal elements: cytokeratins (CK)-5, -7, -8, -14 (two), -16, -18, -19 (three), -20, vimentin and desmin; MUC1 (three); cell adhesion molecules (E-cadherin, alpha-beta-and gamma-catenin); and prostatic associated proteins: prostate specific antigen (PSA), prostatic acid phosphatase (PAP) and androgen receptor (AR). For the PCR, genomic DNA was extracted from the cell lines and from SKOV3 and MCF7 (positive controls). PCR was performed on three variable regions which were then sequenced: AR exon 1 (CAG repeat polymorphism), and two areas of microsatellite instability (MSI): AR exon 8 and hypoxanthine-guanine phosphoribosyl transferase (HPRT) exon 3. RESULTS: All cell lines were CK-8/18 positive and most also expressed CK-7 and -19. Heterogeneous CK-20 expression was detected for the first time in prostatic cell lines. All lines were positive for vimentin and negative for desmin. MUC1 was expressed in one malignant (DU-145) and all immortalized cell lines. E-cadherin expression was low or absent in three lines: PNT1A, 1B and PC-3. Only PC-3 failed to express alpha-catenin; beta- and gamma-catenin were expressed by all lines. PSA, PAP and AR were only expressed by LNCaP and LNCaP-r. On PCR, the CAG repeat lengths in exon 1 of the AR ranged from 19 to 27. Three pairs of cell lines had the same exon 1 CAG repeat length: LNCaP/PC-3 (26 repeats), BPH-1/DU-145 (19 repeats) and PNT1 A/1B (20 repeats). Exon 8 sequences were identical except for LNCaP, which showed a single base mutation, and HPRT exon 3 sequences were all identical. There was no evidence of generalized MSI in any of the cell lines examined. CONCLUSIONS: The cell lines studied fell into three broad groups according to their phenotypic characteristics: (i) prostatic marker positive (LNCaP and LNCaP-r); (ii) high expression of most antigens (DU-145, PC-3 and BPH-1); and (iii) low or absent expression of most antigens (PNT1 A and 1B). Each of the cell lines derived from PC could be identified on the basis of exon 1 and 8 AR sequence variability. DU145 and BPH-1 had identical profiles of the three areas studied, but these cell lines are easily distinguished by their different phenotypic characteristics. PNT1A and 1B had identical genetic and similar phenotypic profiles, which is unsurprising given that they are subclones derived from the same parental line. Even so, these were separable on the basis of CK-19 immunostaining. Using a combination of geno- and phenotypic markers it was possible to derive a 'fingerprint' for each of the cell lines assessed, which will allow meaningful comparison between similar cell lines held in other laboratories.