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。     

Characterization of PacMetUT1, a recently isolated human prostate cancer cell line

BACKGROUND: Existing prostate cancer cell lines have limitations. METHODS: Cells were characterized using Western blotting, immunohistochemistry, invasion into Matrigel, and by studying xenograft tumors. RESULTS: We describe a cell line (PacMetUT1) isolated from a lymph node of a 57-year-old male with prostate cancer. Compared to existing prostate cancer cell lines, the growth rate of PacMetUT1 xenograft tumors is slower with tumors occurring at injection sites and with metastases to lung and liver. Androgen receptor (AR) was detected in vivo by Western blotting and the cells responded to methyltrienolone (R1881). PacMetUT1 cells are more invasive in Matrigel than DU-145, PC-3, and LNCaP cells, and showed greater anchorage-independent growth in soft agar. The cells do not express prostate specific antigen (PSA) in vitro or in xenografts. However, the green fluorescent protein (GFP) gene was introduced and stably expressed in PacMetUT1 cells, allowing tumor imaging in vivo. Xenograft tumors show epithelial features and are positive for keratin, epithelial membrane antigen, EGF receptor, and E cadherin. In contrast, fibroblast markers vimentin, desmin, and Factor VIII, were negative. Karyotyping showed losses of 6p, 7q, 8p, 18q, and 22q, and gains of 8q and 9q; additional genetic material was observed at 2q and 12p. CONCLUSION: The PacMetUT1 cell line allows metastases to be assessed using a single animal model. Because of its slower growth, PacMetUT1 more closely mimics the human disease. Studies of tumor progression or metastasis can be conducted over a longer period of time.     

TRPC6在人良性与恶性前列腺组织中的表达

观察瞬时受体电位通道C6（TRPC6）在人良性与恶性前列腺组织及前列腺癌细胞系中的表达,进一步探讨TRPC6的表达与前列腺癌分期、分级及激素依赖性的关系。利用免疫组织化学技术,检测发现45．0％的前列腺增生和86．6％的前列腺癌病例表达TRPC6,两者比较有显著性差异沪〈0．01）。TRPC6的表达与前列腺癌分级和前列腺外转移有关（P〈0．01）。前列腺癌分期增高,TRPC6表达增多,但在T2、T3和DT4期肿瘤病例中,TRPC6表达无显著差异。此外TRPC6在激素依赖性前列腺癌与激素非依赖性前列腺癌中的表达也无显著差异。应用RT-PCR及Westernblot,检测到TRPC6在前列腺癌细胞系中的表达。本研究发现,TRPC6在良性与恶性前列腺组织及前列腺癌细胞系中表达。TRPC6的表达与前列腺癌的组织分级、Gleason评分及前列腺外转移有关。     

In vitro proton magnetic resonance spectroscopy of four human prostate cancer cell lines

There is accumulating evidence that some biochemical pathways observable by magnetic resonance spectroscopy, e.g., citrate acid and phospholipid metabolism, are altered in human prostate cancer. Four well-established human prostate cancer cell lines were therefore studied with magnetic resonance spectroscopy to compare differences in metabolic content with tumor biological behavior. Herein we demonstrate that, although each cell line has its own metabolic profile, relative creatine and citrate levels can be used to discriminate the androgen-dependent LNCaP cell line from the androgen-independent DU-145, TSU, and PC-3 cell lines.     

Expression of sialylated MUC1 in prostate cancer: Relationship to clinical stage and prognosis

Aim: MUC1 is distributed among a variety of normal epithelial tissues, and overexpression of MUC1 is detected in several human cancers. This study aimed to elucidate whether sialylated MUC1 expression correlated with: (i) clinical stage of prostate cancer; (ii) pathological grade of prostate cancer; (iii) pretreatment serum level of prostate‐specific antigen (PSA); or (iv) the disease prognosis in patients with prostate cancer who received endocrine therapy. Methods: We collected 57 biopsy specimens from prostate cancer patients treated with only endocrine therapy, and 10 specimens of normal prostates. These specimens were stained immunohistochemically by using a novel monoclonal antibody, MY.1E12, to detect sialylated MUC1. The levels of expression, clinical stages, pathological grades, pretreatment serum level of PSA and the prognoses of the patients were statistically analyzed for correlations. Results: There were statistically significant correlations between the expression of sialylated MUC1 and pathological grades (WHO grade, P < 0.01; Gleason score, P < 0.05). Expression increased according to the progression of the disease (existence of clinical metastasis, P < 0.05; clinical T‐stage, P < 0.01). Patients with high serum levels of PSA had higher expression than those with low levels (P < 0.01). The level of sialylated MUC1 significantly correlated with progression‐free survival (P < 0.01) and cause‐specific survival (P < 0.01) according to univariate analyses. Furthermore, the level significantly correlated with progression‐free survival according to multivariate analysis. Conclusions: These results suggest that sialylated MUC1 plays an important role in the progression of prostate cancer, and that its expression level in the primary lesion is a useful marker for the prognoses of patients undergoing endocrine therapy.     

The diverse and contrasting effects of using human prostate cancer cell lines to study androgen receptor roles in prostate cancer

The androgen receptor （AR） plays an important role in the development and progression of prostate cancer （PCa）. Androgen deprivation therapy is initially effective in blocking tumor growth, but it eventually leads to the hormonerefractory state. The detailed mechanisms of the conversion from androgen dependence to androgen independence remain unclear. Several PCa cell lines were established to study the role of AR in PCa, but the results were often inconsistent or contrasting in different cell lines, or in the same cell line grown under different conditions. The cellular and molecular alteration of epithelial cells and their microenvironments are complicated, and it is difficult to use a single cell line to address this important issue and also to study the pathophysiological effects of AR. In this paper, we summarize the different effects of AR on multiple cell lines and show the disadvantages of using a single human PCa cell line to study AR effects on PCa. We also discuss the advantages of widely used epithelium-stroma co-culture systems, xenograft mouse models, and genetically engineered PCa mouse models. The combination of in vitro cell line studies and in vivo mouse models might lead to more credible results and better strategies for the study of AR roles in PCa.     

Aberrant expression of transmembrane mucins, MUC1 and MUC4, in human prostate carcinomas

BACKGROUND: Mucins are considered important markers for early diagnosis and targeted therapy due to their aberrant and unique expression pattern during malignant progression of carcinomas. Recent findings have provided substantial evidence for the involvement of transmembrane mucins, MUC1 and MUC4, in altered cell signaling, tumor growth, and metastasis. METHODS: Immunohistochemical analyses were performed on prostate tumor tissues for expression profiling of the two transmembrane mucins, MUC1 and MUC4. In cancer cell lines, the expression was studied by RT-PCR and immunoblot analyses. Cells were treated with DNA-methylase and histone-deacetylase inhibitors to examine the implication of epigenetic mechanism(s) in MUC4 regulation. RESULTS: The expression of MUC4 was significantly down regulated in prostate cancer tissues (n=38, P=0.0026) compared to normal/benign prostatic hyperplastic regions. A faint to moderate staining was observed in 26.3% cases of cancer, while 84.2% cases of adjacent normal were positive for MUC4 with moderate to strong staining in most cases. Similar observations were made in immortalized normal prostate epithelial and cancer cell lines. MUC1 also showed a reduced expression in prostate tumor tissues; however, its expression was comparable in all normal prostate epithelial and cancer cell lines. Interestingly, we also found that epigenetic mechanism(s) might be implicated in MUC4 gene silencing. CONCLUSIONS: Our data suggest that MUC4 downregulation may be of significance for diagnostic applications in prostate cancer.     

细胞株源人前列腺肿瘤干细胞的分选与鉴定

目的:论证人前列腺癌(prostate cancer,PCa)细胞株中是否存在干细胞亚群。方法:分别用免疫表型法和侧群(side population,SP)细胞法从5种人PCa细胞株(Du145、IA8、LNCaP、TSU-PrL和PC-3)中富集类干细胞,再应用软琼脂克隆形成试验初步验证类干细胞亚群的体外生长方式及成瘤能力。选择LNCaP源SP细胞(LNCaP/SP),依次采用免疫细胞化学技术、Transwell、MTT以及裸鼠致瘤试验,分别检测其干细胞标记物的表达情况、鉴定其体外增殖和侵袭能力以及动物体内的致瘤和转移潜能。结果:5种细胞株中均难以分选出免疫表型为CD133+CD44+的细胞亚群。除PC-3外,其余4株细胞可分选出呈现典型克隆性生长特点的SP细胞。体外克隆形成率在IA8、LNCaP和TSU-PrL源SP细胞与非侧群(non-side population,NSP)细胞间有显著性差异(P<0.05)。与LNCaP/NSP相比,LNCaP/SP的体外增殖和侵袭能力显著增强,同时阳性表达整合素α2、Nanog、CD44、OCT4以及ABCG2等5种干细胞标记物。而且,LNCaP/SP的皮下成瘤率、骨转移率及瘤体体积亦显著高于LNCaP/NSP(P<0.01)。结论:SP分选法更适合富集人PCa细胞株中类干细胞,LNCaP/SP细胞是PCa细胞株LNCaP中的肿瘤干细胞(cancer stem cell,CSC)。     

Steroid sulfatase and estrogen sulfotransferase in human prostate cancer

BACKGROUND: Estrogen sulfotransferase (EST) and steroid sulfatase (STS) are known to be involved in in situ estrogen production in estrogen dependent human cancer such as breast cancer, but unknown in prostate cancer. MATERIALS AND METHODS: We first examined whether these enzymes above were expressed and actually involved in estrogen production and metabolism in prostate cancer cell lines (LNCaP, DU-145, and PC-3). We than examined the expression of EST and STS in human prostate cancer tissues obtained from surgery (n = 52) using immunohistochemistry. RESULTS: mRNAs of both enzymes were detected in all prostate cancer cell lines examined, and the synthesis of estrone (E(1)) and estradiol (E(2)) was also confirmed in these cell lines. In addition, STS immunoreactivity was detected in 44 cases (85%) and EST in 39 cases (75%), respectively. CONCLUSIONS: STS and EST are expressed and may be involved in local production and metabolism of estrogens in human prostate cancers.     

Human cell lines as an in vitro/in vivo model for prostate carcinogenesis and progression

BACKGROUND: The study of prostate carcinogenesis and tumor progression is made difficult by the lack of appropriate in vitro and in vivo models. High prevalence of prostatic intra-epithelial neoplasia and latent prostatic carcinoma, representing multiple steps in carcinogenesis to invasive carcinoma, are relevant targets for cancer prevention. From the RWPE-1, immortalized, non-tumorigenic, human prostate epithelial cell line, we have derived four tumorigenic cell lines with progressive malignant characteristics. METHODS: Cell lines were derived by exposure of RWPE-1 to N-methyl-N-nitrosourea (MNU), selected and cloned in vivo and in vitro, and characterized by prostatic epithelial and differentiation markers, karyotype analysis, anchorage-independent growth, invasiveness, tumorigenicity, and pathology of the derived tumors. RESULTS: Cytokeratins 8 and 18, androgen receptor, and prostate-specific antigen expression in response to androgen, confirm prostatic epithelial origin. RWPE-1 cells do not grow in agar and are not tumorigenic in mice, but the growth, tumorigenicity, and tumor pathology of the MNU cell lines correlate with their invasive ability. The WPE1-NA22 (least malignant) form small, well-differentiated, and WPE1-NB26 cells (most malignant) form large, poorly differentiated, invasive tumors. Overall, loss of heterozygosity for chromosomes 7q, 13q, 18q, and 22, and gain of 5, 9q, 11q, and 20, was observed. The MNU cell lines, in order of increasing malignancy are; WPE1-NA22, WPE1-NB14, WPE1-NB11, and WPE1-NB26. CONCLUSIONS: This family of cell lines with a common lineage represents a unique and relevant model which mimics stages in prostatic intra-epithelial neoplasia (PIN) and progression to invasive cancer, and can be used to study carcinogenesis, progression, intervention, and chemoprevention.     

Overexpression of the EphA2 tyrosine kinase in prostate cancer.

BACKGROUND: Molecules that are highly expressed by human prostate cancers may serve as therapeutically relevant targets or tumor markers. Tyrosine kinases are frequently overexpressed in metastatic tumor cells and this prompted us to screen for tyrosine kinases that are overexpressed in prostate cancer cells. METHODS: Expression levels of the EphA2 receptor tyrosine kinase were determined by Western blot analysis in canine and human prostate cancer cell lines and in immortalized and transformed variants of 267B1 prostatic epithelial cells. EphA2 levels in benign human prostate and prostate cancers were also determined in formalin-fixed, paraffin-embedded tissues using immunohistochemical staining. RESULTS: Metastatic prostate cancer cells overexpressed EphA2 by 10-100 fold as compared with non-invasive prostatic epithelial cells. EphA2 immunoreactivity in vivo was also significantly greater in human prostate cancers as compared with benign prostate epithelium. CONCLUSIONS: The EphA2 receptor tyrosine kinase is differentially expressed in human and canine prostate cancer cell lines and overexpressed in human prostate cancers as compared with benign prostate tissues. Metastasis-derived canine prostate carcinoma cell lines overexpress EphA2 and may provide pre-clinical models to further evaluate the role of EphA2 in prostate carcinogenesis. Further investigations are needed to determine the utility of EphA2 as a tumor marker and a novel target in human prostate cancer.     

CD146与前列腺癌微血管生成关系的研究

目的探讨前列腺癌(PCa)组织中CD146(Mel-CAM,MUC18)的表达与其微血管形成的关系。方法采用免疫组化(EnVision+TM)方法检测45例PCa、24例良性前列腺增生(BPH)组织中CD146蛋白的表达和CD34标记的肿瘤微血管数目和密度(MVD)值。结果CD146蛋白在BPH和PCa组织阳性表达率分别为12.5%和82.2%;BPH与PCa组织的MVD值分别为20.40±10.25和36.10±9.94;两者均较对照组(BPH)差异有统计学意义(P<0.01)。CD146阳性组与CD146阴性组间的MVD值存在显著性差异(P<0.01)。CD146的表达与PCa分化程度、临床病理分期无统计学意义(P>0.05)。结论CD146表达是PCa形成的早期事件,CD146可能参与了前列腺癌浸润和转移过程;CD146在前列腺癌微血管形成过程中发挥了重要作用;CD146可作为判断前列腺癌预后的指标和治疗的新靶点。     

实时荧光定量检测胃癌患者MUC1基因表达及临床意义

目的:检测胃癌患者肿瘤组织及外周血MUC1 mRNA的表达水平,探讨MUC1 mRNA表达的临床意义.方法:利用实时荧光定量PCR(RT-PCR)方法检测胃癌组织、正常组织及外周血中MUC1mRNA水平,分析其表达与肿瘤临床病理因素的关系.结果:胃癌患者肿瘤组织及外周血MUC1 mRNA表达水平高于正常对照组(P<0.05),肿瘤组织MUC1 mRNA的检出率与肿瘤的分化程度、淋巴结转移、血行转移及临床分期有关(P<0.05),外周血MUC1 mRNA的检出率与肿瘤的淋巴结转移、血行转移及临床分期有相关(P<0.05).结论:检测胃癌组织及外周血MUC1 mRNA的表达有助于早期发现胃癌及其微转移.     

Expression of focal adhesion kinase in normal and pathologic human prostate tissues

BACKGROUND: Focal adhesion kinase (FAK) regulates multiple cellular processes including growth, differentiation, adhesion, motility, and apoptosis. In tumor cells, including prostate adenocarcinoma, FAK overexpression has been linked to cancer progression. METHODS: By using immunohistochemistry, FAK expression was investigated in human prostate specimens. RESULTS: FAK was expressed predominantly in the basal layer of normal prostate epithelium but not in secretory epithelium. FAK was expressed at similar levels in all stages of prostate tumorigenesis, including preinvasive carcinoma and metastatic disease. Elevated FAK expression was observed at the earliest stages of transformation and expression continued during cancer progression. CONCLUSION: Given the established role for FAK in the regulation of integrin signaling, we suggest that the sustained elevated levels of FAK expression during prostate tumor cell progression is consistent with a role for FAK in the development and maintenance of prostate carcinoma.     

前列腺癌组织中人软骨糖蛋白-39的表达及意义

目的 探讨人软骨糖蛋白-39在前列腺癌组织中的表达及临床意义.方法 应用免疫组织化学法检测70例前列腺癌组织、30例前列腺增生组织及10例正常前列腺组织中人软骨糖蛋白-39的表达水平.结果 前列腺癌组人软骨糖蛋白-39表达明显高于前列腺增生组和正常前列腺组,差异有统计学意义(P＜0.01);人软骨糖蛋白-39的表达在前列腺癌不同病理分级及临床分期中表达不同;生存分析显示人软骨糖蛋白-39阳性患者生存时间短于阴性患者(P＜0.05).结论 人软骨糖蛋白-39的表达与前列腺癌发生、发展及预后有密切的关系,检测前列腺组织中人软骨糖蛋白-39的表达有助于预后的评估.     

Virology studies and cell lines for prostate cancer

Immunological and biochemical probes for viral genomes and products, growth in cell culture, co-culture methods to activate latent genomes, use of activating agents, and electron microscopy have been used in efforts to demonstrate RNA viruses in prostate cancer. Despite findings of C-type particles and p30 antigens, the role of RNA viruses appears to be secondary, with activation of the virogene being a relatively uncommon occurrence. No compelling evidence for Herpes II or cytomegalovirus as etiologic agents has emerged, despite their common presence in the urogenital tract. Though the search for integration of fragments of viral genome into host DNA is still in progress, it appears unlikely that these viruses would account for a significant number of prostate carcinomas. Progress has been achieved in developing simple, reliable, primary culture methods for human prostatic tissue, using explants or dispersed cells. Three cell lines, all from metastatic foci, have been established, are characterized, and are available for distribution. One neonatal cell strain retains many properties of normal prostate.