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.     

人乳腺癌细胞株透明质酸酶的表达及其意义

目的：通过检测人乳腺癌细胞株透明质酸酶（Hyse）水平的表达，并与雌激素受体（ER）、以及血管内皮生长因子（VEGF）、基质金属蛋白酶－9（MMP－9）和组织蛋白酶－D（Cath-D）比较，探讨Hyse在乳腺癌侵袭、转移及预后评价中的作用。方法：应用细胞培养技术、酶联免疫吸附测定和免疫组织化学等方法分别测定10株人乳腺癌细胞的Hyse,以及VEGF、MMP－9、和Cath-D的表达。结果：10株人乳腺癌细胞Hyse的表达存在明显差异。ER（＋）细胞株Hyse表达低水平，EP（－）细胞株Hyse表达高水平（P＜0．01）。Hyse高表达细胞株中VEGF、MMP－9和Cath-D的表达明显高于Hyse低表达细胞株（P＜0．05）。结论：Hyse与乳腺癌的侵袭、转移潜能及预后有一定的相关性。     

Functional angiotensin II type 2 receptors inhibit growth factor signaling in LNCaP and PC3 prostate cancer cell lines

BACKGROUND: There is clear evidence of a tissue-based renin-angiotensin system in the prostate and studies to date suggest that AT(1)-receptor blocking drugs inhibit the growth of some prostate cancer cell lines and delay the development of prostate cancer. The present studies examine the action of Ang II in two prostate cancer cell lines and report the presence of functional AT(2)-receptors that regulate the actions of growth factors. METHODS: Immunohistochemistry was used to identify the presence of Ang II and QPCR techniques to examine AT(1)- and AT(2)-receptor mRNA expression in androgen-dependent (LNCaP) and independent (PC3) cell lines. The effects of AT(1)- and AT(2)-receptor activation upon EGF-induced DNA synthesis and ERK2 phosphorylation in these cells were also examined. RESULTS: Functional AT(2)-receptors together with Ang II were identified in both cell lines and stimulation of these receptors inhibited EGF-induced DNA synthesis and ERK2 phosphorylation. AT(1)-receptors, although present in both cell lines, were only functional in LNCaP cells where activation stimulated DNA synthesis. CONCLUSIONS: Functional AT(2)-receptors are present and have the capacity to inhibit EGF-induced prostate cancer cell growth in LNCaP and fast growing androgen-independent PC3 cell lines, whereas functional AT(1)-receptors are found only in LNCaP cells where their activation stimulates DNA synthesis.     

Immortalized and tumorigenic adult human prostatic epithelial cell lines: Characteristics and applications part 2. Tumorigenic cell lines

This is Part 2 of a three-part review and deals with tumorigenic cell lines. Several immortalized and malignant adult human prostatic epithelial cell lines have been recently developed. The three most widely used carcinoma cell lines—DU-145, PC-3, and LNCaP—developed between 1977 and 1980, have greatly contributed to our current understanding of prostate cancer. Before a cell line can be accepted as having prostatic epithelial origin, some basic characteristics must be established. Expression of specific cytokeratins but absence of desmin and factor VIII should be first determined to establish epithelial origin. Responsiveness to androgens and expression of androgen receptor and prostate-specific antigen should be examined under stringent culture conditions to establish prostatic epithelial origin. Response to growth factors and expression of their receptors facilitates further characterization of cell behavior. Cell lines immortalized by human papillomaviruses (HPVs) are of special interest because HPVs are involved in a variety of anogenital cancers and may also play a role in prostate carcinogenesis. Malignant transformation of HPV-18 immortalized cells with the ras oncogene provides cell systems for investigating the multistep process of carcinogenesis. Each cell line has some unique characteristics, whether it arose directly from a carcinoma or resulted from immortalization with Simian virus 40 (SV40) or HPV, or was transformed in vitro by oncogenes. Comparisons of these characteristics should facilitate elucidation of the mechanisms involved in the initiation, promotion, and progression of prostate cancer. These cell lines will further serve as useful models for investigating tumor progression, invasion, metastasis, new therapeutic strategies, drug resistance, and its reversal and chemoprevention. The nontumorigenic cell lines were discussed in Part 1 [1]. This review summarizes the characteristics of several currently available tumorigenic, adult human prostatic epithelial cell lines. Prostate 30:58–64, 1997 © 1997 Wiley-Liss, Inc.     

畸胎瘤细胞源性生长因子对雌激素受体阴性乳腺癌细胞雌激素依赖性的影响

目的分析乳腺癌细胞雌激素依赖性与畸胎瘤细胞源性生长因子（PC—cell derived growth factor,PCDGF）表达之间的关系,探讨雌激素受体（ER）阴性乳腺癌患者接受内分泌治疗的可能性。方法荧光定量聚合酶链反应检测乳腺癌细胞系MCF-7、MDA-MB-231、T47D、MDA-MB-435s中PCDGF的表达,CCK-8法检测不同浓度雌激素培养条件下细胞的存活情况。以ER阳性乳腺癌细胞系MCF-7为对照,用RNA干扰技术抑制ER阴性乳腺癌细胞系MDA-MB-231中PCDGF基因的表达,观察抑制前后雌激素依赖性的变化。结果PCDGF在4株乳腺癌细胞系中均有不同程度的表达,其中在MDA-MB-435s中表达量最高,PCDGF高表达的乳腺癌细胞系的雌激素依赖性较高,PCDGFshRNA可以有效抑制乳腺癌细胞系MCF-7和MDA-MB-213中PCDGF的表达（抑制率分别为81．1％和86．7％）。MDA-MB-231细胞系雌激素依赖性增加的程度高于MCF-7细胞系（P〈0．05）。结论PCDGF高表达于ER阴性乳腺癌细胞,抑制其表达可能会更好的逆转内分泌治疗的耐药性。     

乳腺癌耐药蛋白的表达及其与核转录因子snail相关性的临床研究

目的：探讨乳腺癌耐药蛋白（BCRP）的表达,分析其与核转录因子snail的相关性及BCRP介导肿瘤耐药的分子机制。方法：应用免疫组化方法检测87例乳腺癌组织和35例癌旁组织中BCRP和snail的表达情况,分析其与乳腺癌临床病理因素的关系及BCRP与snail的相关性。结果：BCRP和snail在乳腺癌组织中的阳性率分别32．18％和85．06％,BCRP与年龄、肿瘤大小及TNM分期无关,与组织学分级、ER表达和淋巴结转移相关;snail与患者年龄、肿瘤大小、组织学分级、ER表达无关,而与TMN分期、淋巴结璜移正相关;相关分析显示BCRP与snail表达的存在密切相关性（x^2=35267,P〈001,r=O643）。结论：BCRP参与了乳腺癌的进展;snail是乳腺癌上皮-间质转换（EMT）过程中的一个重要调节因素,促进了EMT的发生,介导了BCRP介导的多药耐药。     

Karyotype analyses of 20 human glioma cell lines

Summary Human malignant gliomas are frequently associated with loss of gonosomes and chromosomes 13, 17, and 22. Their progression from anaplastic glioma to glioblastoma is marked by additional loss of chromosome 10. In addition, structural and numerical aberrations of chromosome 7 are frequently found. We report on the karyotypes of a series of 20 human gliomas of which 11 were analysed as established cell lines; 9 cases were investigated in early culture, 5 of which later also became established lines.In addition to the frequently reported overrepresentation of chromosome 7, four cell lines with polysomy for chromosome 22 were seen. A high incidence of structural chromosomal aberrations was present in early cultures as well as in cell lines after various in vitro passages. We found that the general characteristics of karyotypic aberrations found in early cultures or direct preparations of dispersed tumour material were reflected in the pattern of aberrations present in cell lines at much later time points. Thus it appears as if no systematic changes can be attributed to long-term cultures. Suspicious losses of chromosomes 14, 18, and 19 or gain of chromosome 22 indicate that individual cases may have originated due to other mechanisms than the ones already hypothesized, i.e., different suppressor genes or amplification of genes other than the EGF-R-gene. None of the established cell lines had a genomic rearrangement of c-erbB 1, c-erbB 2 or of the p 53 gene.Dedicated to Prof. Dr. H.-D. Herrmann on the occasion of his 60th birthday.     

SELDI protein profiling of dunning R-3327 derived cell lines: identification of molecular markers of prostate cancer progression

BACKGROUND: We recently demonstrated the protein expression profiling of Dunning rat tumor cell lines of varying metastatic potential (G (0%), AT-1 ( approximately 20%), and MLL (100%)) using SELDI-TOF-MS. As a parallel effort, we have been pursuing the identification of the protein(s) comprising the individual discriminatory "peaks" and evaluating their utility as potential biomarkers for prostate cancer progression. METHODS: To identify the observed SELDI-TOF-MS m/z (mass/charge) values with discriminatory expression between different sublines, we employed a combination of chemical pre-fractionation, liquid chromatography, gel electrophoresis and tandem mass spectroscopy. Identified proteins were then verified by immuno-assay and Western analysis. RESULTS: A 17.5 K m/z SELDI-TOF-MS peak was found to retain discriminatory value in each of two separate study-sets with an increased expression in the metastatic MLL line. Sequence identification and subsequent immunoassays verified that Histone H2B is the observed 17.5 K m/z SELDI peak. SELDI-based immuno-assay and Western Blotting revealed that Histone H2B is specifically over-expressed in metastatic MLL lines. CONCLUSIONS: SELDI-TOF MS analysis of the Dunning prostate cancer cell lines confirmed the consistent overexpression of a 17.5 K m/z peak in metastatic MLL subline. The 17.5 kDa protein from MLL has been isolated and identified as Histone H2B.     

THYROID CANCER: PREDISPOSING CONDITIONS,GROWTH FACTORS,SIGNAL TRANSDUCTION AND ONCOGENES

This article summarizes much of the information that is available on factors, such as oncogenes and tumour suppressor genes, that cause thyroid neoplasms and cancers to develop, grow and invade.     

雌激素受体在人乳腺癌MCF-7细胞阿霉素敏感株和耐药株中的变化及意义

目的研究MCF 7人乳腺癌细胞阿霉素敏感株 (MCF 7)和耐药株 (MCF 7/ADR)细胞中雌激素受体 (estrogenreceptor,ER)表达的变化与其对细胞生物学特性的影响。方法采用Westernblot法检测MCF 7细胞和MCF 7/ADR细胞中雌激素受体表达 ,RT PCR检测 2株细胞ERmRNA的表达水平 ,MTT法检测细胞增殖及细胞对雌激素 (estrogen ,E2 )和屈洛昔芬 (droloxifene ,Dro)的敏感性 ,流式细胞仪检测细胞周期变化。结果经Westernblot检测 ,MCF 7细胞ER为阳性 ,而MCF 7/ADR细胞ER为阴性 ,采用RT PCR可检测到MCF 7细胞中ER的mRNA ,而在MCF 7/ADR细胞则检测不到。经MTT分析 ,与MCF 7相比 ,MCF 7/ADR细胞生长速度减慢 ,细胞多分布于G0 /G1期。E2 在 1× 10 -12mol/L的浓度时开始促进MCF 7细胞的生长 ,到达 1× 10 -9mol/L时促生长作用进入平台期 ;而任何浓度的E2 对MCF 7/ADR细胞均无促生长作用。Dro的浓度达到 10 μmol/L的时候 ,开始出现对MCF 7细胞生长的浓度依赖性抑制 ,当Dro浓度达到 2 0 μmol/L时对MCF 7/ADR细胞的生长出现明显抑制 ,且高于对MCF 7细胞的抑制。结论MCF 7/ADR细胞雌激素受体表达缺失 ,缺失发生在mRNA水平以上 ,细胞生长速度减慢 ,同时细胞失去对雌激素的依赖性。     

Metastatic disease of the breast and local recurrence of breast cancer

Breast cancer is a major health problem worldwide with over 1 million new cases diagnosed each year. The aim of treatment is to achieve good loco-regional control, provide appropriate adjuvant therapy and treat potential micro-metastasis. Early detection with breast screening and better treatment options have improved outcome. However approximately 40% of patients will suffer a recurrence and still 35–40% will eventually present with metastatic disease. Metastatic disease is incurable with the median survival being 2–3 years. Several therapies have been shown to maintain a good quality of life whilst prolonging survival. In certain sub-groups of breast cancer, that is, human epidermal growth factor receptor 2 (HER2)-positive cancer the advent of trastuzumab has improved survival rates. A multidisciplinary team approach is essential to obtain the diagnosis and plan the appropriate treatment. The diagnosis of metastatic disease brings distress to patients and their relatives and support should be available from palliative care teams.     

Prognostic Factors in Breast Cancer

Abstract: The overwhelming interest in breast cancer among researchers, clinicians, diagnosticians, and the public has resulted in an extensive search for better understanding and better control of the disease. The use of traditional, as well as the newly recognized, prognostic factors in breast cancer is an attempt to identify high-risk breast lesions and administer a more aggressive therapeutic approach to minimize the possibility or progression of this disease. Herein the clinical significance of various prognostic factors are discussed and the need for a better standardized approach is emphasized.     

Genetic analysis of breast cancer progression

At the histological level, breast tumors display a variety of morphologic lesions which suggest the existence of an increasingly aberrant pathway of intermediate steps leading to the invasive primary tumor and its metastatic dissemination. In order to obtain direct evidence for this presumed progression, underlying genetic changes must be identified. Analyses of primary breast tumors have revealed a large number of dominant and recessive gene alterations encompassing several cellular attributes and activities. It is quite likely that some of these alterations are of a causal nature and thus enable the tumor to attain distinctive malignant phenotypes, such as, dysregulated proliferation, invasion, angiogenesis, and ability to metastasize. Considerable heterogeneity has been observed in the sequence of acquisition of these genetic changes, which is substantiated by recent comparative analyses between carefully microdissected preinvasive and invasive tumor. The data are evaluated here in the context of existing models of breast cancer progression. Implications and prospects for translational application to the clinic are also discussed.     

HOX基因家族在食管癌细胞系中表达的研究

目的为探讨HOX基因能否成为食管癌分子标记物寻找证据。方法应用针对HOX基因家族不同成员的特异性引物,采用RT-PCR的方法检测39个HOX基因在人食管癌细胞系EC109和CAES中的表达。结果全部39个成员中有15个成员在该两个细胞系中表达,它们是HOXA2、HOXA7、HOXA9、HOXA10、HOXA13、HOXB7、HOXB9、HOXC4、HOXC5、HOXC6、HOXC8、HOXC9、HOXD9、HOXD10和HOXD13。与前期研究发现的在食管癌组织中表达异常者重叠(11个)。结论从细胞系水平再次验证了HOX基因在食管癌中表达异常,为利用HOX基因作为食管癌标记物提供了更多的证据。     

瘦素在乳腺癌发病中的作用

瘦素是一种由肥胖基因(ob基因)编码表达的小分子蛋白,在调控机体的摄食行为和脂肪代谢方面具有重要作用.近来大量研究发现瘦素在体外可促进乳腺细胞转化、癌细胞增生并促进血管生成.这表明瘦素在乳腺癌的发生发展中可能起重要作用,但具体机制尚未阐明.本文主要从体外实验、动物试验和乳腺癌病理组织研究3方面对瘦素在乳腺癌发病中的作用的近年相关研究进展进行综述.