Proteomic analysis of human pleural effusion

Pleural effusion, an accumulation of pleural fluid, contains proteins originating from plasma filtrate and, especially when tissues are damaged, parenchymal interstitial spaces of lungs and/or other organs. This report presents data of the first global proteomic analysis of human pleural effusion. A composite sample was prepared by pooling pleural effusions from seven lung adenocarcinoma patients. Two-dimensional gel electrophoresis analysis of the composite sample revealed 472 silver-stained spots. 242 selected gel spots were subjected to protein identification by in-gel digestion, liquid chromatography-tandem mass spectrometry, and sequence database search. 44 proteins were identified with higher confidence levels (at least two unique peptide sequences matched), while 161 other proteins were identified at the minimal confidence level (only one unique peptide sequence matched). The data provide fundamental information on the composition of protein contents in human pleural effusion. Among these 44 proteins that were identified with higher confidence levels, 7 proteins, retinoblastoma binding protein 7, synaptic vesicle membrane protein, corticosteroid binding globulin precursor, PR-domain containing protein 11, envelope glycoprotein, MSIP043 protein, and titin have not been reported in plasma and may represent proteins specifically present in pleural effusion. These proteins could have originated from parenchymal interstitial spaces and represent potential candidates of useful biomarkers that could not be readily detected in plasma but in pleural effusion. Retinoblastoma binding protein 7 is of special interest since it may play a role in the regulation of cell proliferation and differentiation.     

Use of narrow‐range peptide IEF to improve detection of lung adenocarcinoma markers in plasma and pleural effusion

In this study we applied narrow‐range peptide IEF to plasma or pleural effusion prior to LC/MS/MS. Two methods for narrow‐range IEF were run; IPG strips and free‐flow electrophoresis. Data from this study was compared with cell line data to evaluate the method performance in body fluids. To test the methods potential in quantitative biomarker discovery studies, plasma and pleural effusion from patients with lung adenocarcinoma (n=3) were compared with inflammatory pleuritis (n=3) using iTRAQ quantification. Using narrow‐range IEF on the peptide level we were able to identify and quantify 282 proteins in plasma and 300 proteins in pleural effusion. These body fluid proteomes demonstrated high degree of overlap; however, more proteins significantly differently altered levels related to adenenocarcinoma were found in pleural effusion compared with plasma, suggesting enrichment of lung tissue‐related proteins in pleural effusion. Nine proteins were chosen for initial validation with Western blot, and one protein (NPC2) was chosen for further validation using imunohistochemistry. Overall, the quantitative results from IEF/LC/MS/MS showed good correlation with the results from Western blot and imunohistochemistry, showing the potential of this methodology in quantitative biomarker discovery studies.     

Clinical-scale high-throughput human plasma proteome analysis: lung adenocarcinoma

Clinical proteomics requires the stable and reproducible analysis of a large number of human samples. We report a high-throughput comprehensive protein profiling system comprising a fully automated, on-line, two-dimensional microflow liquid chromatography/tandem mass spectrometry (2-D microLC-MS/MS) system for use in clinical proteomics. A linear ion-trap mass spectrometer (ITMS) also known as a 2-D ITMS instrument, which is characterized by high scan speed, was incorporated into the microLC-MS/MS system in order to obtain highly improved sensitivity and resolution in MS/MS acquisition. This system was used to evaluate bovine serum albumin and human 26S proteasome. Application of these high-throughput microLC conditions and the 2-D ITMS resulted in a 10-fold increase in sensitivity in protein identification. Additionally, peptide fragments from the 26S proteasome were identified three-fold more efficiently than by the conventional 3-D ITMS instrument. In this study, the 2-D microLC-MS/MS system that uses linear 2-D ITMS has been applied for the plasma proteome analysis of a few samples from healthy individuals and lung adenocarcinoma patients. Using the 2-D and 1-D microLC-MS/MS analyses, approximately 250 and 100 different proteins were detected, respectively, in each HSA- and IgG-depleted sample, which corresponds to only 0.4 microL of blood plasma. Automatic operation enabled the completion of a single run of the entire 1-D and 2-D microLC-MS/MS analyses within 11 h. Investigation of the data extracted from the protein identification datasets of both healthy and adenocarcinoma groups revealed that several of the group-specific proteins could be candidate protein disease markers expressed in the human blood plasma. Consequently, it was demonstrated that this high-throughput microLC-MS/MS protein profiling system would be practically applicable to the discovery of protein disease markers, which is the primary objective in clinical plasma proteome projects.     

Differential proteome profiling of pleural effusions from lung cancer and benign inflammatory disease patients

The pleural effusion proteome has been found containing information that directly reflects pathophysiological status and represents a potential diagnostic value for pulmonary diseases. However, the variability in protein composition between malignant and benign effusions is not well understood. Herein, we investigated the changes of proteins in pleural effusions from lung adenocarcinoma and benign inflammatory disease (pneumonia and tuberculosis) patients by two-dimensional difference gel electrophoresis (2D-DIGE). Twenty-eight protein spots displayed significantly different expression levels were positively identified by MALDI-TOF-MS representing 16 unique proteins. Five identified protein candidates were further validated and analyzed in effusions, sera or tissues. Among them, hemopexin, fibrinogen gamma and transthyretin (TTR) were up-regulated in cancer samples. The effusion concentration of serum amyloid P component (SAP) was significantly lower in lung cancer patients than in benign inflammatory patients, but no differences were found in sera samples. Moreover, a Jumonji C (JmjC)-domain-containing protein, JMJD5, was observed to be down-regulated in malignant effusions, lung cancer tissues and cancer cells. These results shed light on the altered pleural effusion proteins as a useful and important complement to plasma or other routine clinical tests for pulmonary disease diagnosis.     

Interleukin -1beta (IL-1 beta), interleukin 6 (IL-6) and tumor necrosis factor (TNF) in plasma and pleural fluid of pneumonia, lung cancer and tuberculous pleuritis

Interleukins IL-1beta, IL-6 and TNF are increased in plasma of patients with severe infections and septic shock. Our objective was the evaluation of IL-1beta, IL-6 and TNF in plasma and exudates of pleural fluid and their contribution to the diagnosis. We studied 44 patients, 27 men and 17 women with mean age 66.81 +/- 11.75 years; 16 with pneumonia and parapneumonic effusion, 14 with primary lung cancer and pleural effusion and 14 with tuberculous pleuritis. We measured IL-1beta, IL-6 and TNF in serum and pleural fluid with ELISA. In patients with pneumonia and parapneumonic effusion the mean value of IL-1beta IL-6 and TNF in plasma was 9.05, 19.24 and 21.34 pg/ml and in pleural fluid 10.34, 32.19 and 25.30 pg/ml. In patients with lung cancer the mean values of IL-1beta, IL-6 and TNF were 5.33, 11.74 and 11.51 pg/ml and 6.70, 13.13, 20.89 pg/ml, respectively. In those with tuberculous pleuritis the respective mean values were 10.33, 49.94, 21.27 pg/ml and 14, 56.59, 23.58 pg/ml. In conclusion, IL-1beta and IL-6 were found increased in plasma and tuberculous pleural fluid, indicating an inflammatory status.     

肺腺癌细胞中EGFR蛋白的表达与细胞内胶原化的相关性研究

目的探讨表皮生长因子受体（epidermal growth factor receptor,EGFR）在肺腺癌细胞中的表达及与细胞发生胶原化的相关性。方法从胸水中提取肺腺癌细胞为研究对象,以32例良性胸水中的增生上皮细胞、炎性细胞为对照,采用免疫细胞化学方法检测细胞中EGFR、E钙粘素蛋白、Vimentin、TTF-1和胶原蛋白亚型I的表达。Masson染色方法检测胶原纤维表达。结果78例胸水标本中,EGFR在肺腺癌细胞中的阳性率为79．5％,胶原蛋白亚型I为32．1％,Masson染色的阳性率为70．5％,明显高于对照组且EGFR和Masson染色的阳性表达结果的相关性具有统计学意义（P〈0．01）。结论EG—FR在肺腺癌细胞中阳性表达,可能与细胞内基质胶原蛋白形成有关。     

Identification and characterization of proteins isolated from microvesicles derived from human lung cancer pleural effusions

Microvesicles (MVs, also known as exosomes, ectosomes, microparticles) are released by various cancer cells, including lung, colorectal, and prostate carcinoma cells. MVs released from tumor cells and other sources accumulate in the circulation and in pleural effusion. Although recent studies have shown that MVs play multiple roles in tumor progression, the potential pathological roles of MV in pleural effusion, and their protein composition, are still unknown. In this study, we report the first global proteomic analysis of highly purified MVs derived from human nonsmall cell lung cancer (NSCLC) pleural effusion. Using nano‐LC–MS/MS following 1D SDS‐PAGE separation, we identified a total of 912 MV proteins with high confidence. Three independent experiments on three patients showed that MV proteins from PE were distinct from MV obtained from other malignancies. Bioinformatics analyses of the MS data identified pathologically relevant proteins and potential diagnostic makers for NSCLC, including lung‐enriched surface antigens and proteins related to epidermal growth factor receptor signaling. These findings provide new insight into the diverse functions of MVs in cancer progression and will aid in the development of novel diagnostic tools for NSCLC.     

Comprehensive proteome analysis of malignant pleural effusion for lung cancer biomarker discovery by using multidimensional protein identification technology

Malignant pleural effusion (MPE) obtained from lung adenocarcinoma may contain potentially useful biomarkers for detection of lung cancer. In this study, we used a removal system for high-abundance proteins followed by one-dimensional SDS-PAGE combined with nano-LC-MS/MS to generate a comprehensive MPE proteome data set with 482 nonredundant proteins. Next, we integrated the MPE proteome and secretome data sets from three adenocarcinoma cell lines, with a view to identifying potential PE biomarkers originating from malignant cells. Four potential candidates, alpha-2-HS-glycoprotein (AHSG), angiogenin, cystatin-C, and insulin-like growth factor-binding protein 2, (IGFBP2), were isolated for preclinical validation using ELISA. Both AHSG and IGFBP2 levels were increased in lung patients with MPE (n = 68), compared to those with nonmalignant pleural effusion (n = 119). Notably, the IGFBP2 level was higher in MPE, compared with that in benign diseases (bacteria pneumonia and tuberculosis pleuritis), and significantly associated with malignancy, regardless of the cancer type. Our data additionally support an extracellular function of IGFBP2 in migration in lung cancer cells. These findings collectively suggest that the adenocarcinoma MPE proteome provides a useful data set for malignancy biomarker research.     

肺癌患者胸水游离氨基酸分析

本文对11例肺癌患者胸水13种游离氨基酸作了分析,并与28例正常人血浆游离氨基酸水平作了对照,结果表明:肺癌患者胸水的必需及非必需氨基酸普遍高于正常人血浆游离氨基酸,但其胸水谷氨酰胺水平则明显低于正常人血浆水平。     

MMP-2 VEGF在肺腺癌细胞中的表达及其意义

目的研究探讨基质金属蛋白酶2(MMP-2)及血管内皮生长因子(VEGF)在胸腔积液、痰液中肺腺癌细胞的不同表达及二者在肺癌细胞侵袭转移过程中的相互关系。方法选择胸腔积液、痰液共计264例癌性及异型增生细胞标本经免疫细胞化学方法分别检测MMP-2 VEGF的表达情况。结果免疫细胞化学结果显示:MMP-2在胸腔积液中腺癌细胞、异型增生上皮细胞的表达率分别为71.7%(99/138)、16.7%(6/36),在胸膜炎和结核病变典型良性胸腔积液增生上皮细胞中不表达;在痰腺癌细胞中的表达率为39.1%(27/69),统计结果显示MMP-2在恶性胸腔积液腺癌细胞中的表达率明显高于在异型增生的上皮、增生的上皮及痰腺癌细胞的表达率(P均0.05)。VEGF在胸腔积液中腺癌细胞、异型增生上皮细胞的表达率分别为89.1%(123/138)、33.3%(12/36),在胸膜炎和结核病变典型良性胸腔积液增生上皮细胞中不表达;在痰腺癌细胞中的表达率为47.8%(33/69),VEGF在恶性胸腔积液腺癌细胞中表达率明显高于在异型增生的上皮细胞、增生的上皮细胞及痰腺癌细胞的表达率(P均0.05),且MMP-2同VEGF总阳性表达率之间成正相关(r=0.867,P=0.049)。结果 MMP-2 VEGF在胸水腺癌细胞中高表达,可能与肺腺癌的转移、侵袭有关;两者联合做免疫细胞化学检查对肺腺癌细胞病理诊断有辅助意义。     

Role of monocyte chemoattractant protein-1, tumor necrosis factor-alpha and interleukin-6 in the control of malignant pleural effusion and survival in patients with primary lung adenocarcinoma

This study aimed at assessing the role of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in the control of pleural effusion (PE) and survival in patients with primary lung adenocarcinoma. The concentrations of the 3 cytokines were measured in PE from 79 lung adenocarcinoma patients with malignant pleural effusion (MPE) and 23 patients with tuberculosis. Data were correlated with the efficacy of MPE control and patient survival. The level of MCP-1 in PE was significantly higher in patients with lung adenocarcinoma than those with tuberculosis. By contrast, the levels of TNF-alpha and IL-6 were significantly lower in patients with lung adenocarcinoma than those with tuberculosis. An MCP-1 level greater than 3,187 pg/mL (which was used as a cutoff point) indicated failure to control MPE (odds ratio [OR]=2.82, 95% confidence interval [CI]=1.02-7.82, p=0.04). In multivariate analysis, MCP-1 was confirmed as an independent prognostic factor for progression-free survival (hazard ratio [HR]=2.02, 95% CI=1.24-3.30, p=0.01). The level of MCP-1 in PE appears to be a reliable surrogate marker for evaluating the therapeutic efficacy in the control of MPE and predicting survival in lung adenocarcinoma patients with MPE.     

Human body fluid proteome analysis

The focus of this article is to review the recent advances in proteome analysis of human body fluids, including plasma/serum, urine, cerebrospinal fluid, saliva, bronchoalveolar lavage fluid, synovial fluid, nipple aspirate fluid, tear fluid, and amniotic fluid, as well as its applications to human disease biomarker discovery. We aim to summarize the proteomics technologies currently used for global identification and quantification of body fluid proteins, and elaborate the putative biomarkers discovered for a variety of human diseases through human body fluid proteome (HBFP) analysis. Some critical concerns and perspectives in this emerging field are also discussed. With the advances made in proteomics technologies, the impact of HBFP analysis in the search for clinically relevant disease biomarkers would be realized in the future.     

Identification of Five Candidate Lung Cancer Biomarkers by Proteomics Analysis of Conditioned Media of Four Lung Cancer Cell Lines

Detection of lung cancer at an early stage is necessary for successful therapy and improved survival rates. We performed a bottom-up proteomics analysis using a two-dimensional LC-MS/MS strategy on the conditioned media of four lung cancer cell lines of different histological backgrounds (non-small cell lung cancer: H23 (adenocarcinoma), H520 (squamous cell carcinoma), and H460 (large cell carcinoma); small cell lung cancer: H1688) to identify secreted or membrane-bound proteins that could be useful as novel lung cancer biomarkers. Proteomics analysis of the four conditioned media allowed identification of 1,830 different proteins (965, 871, 726, and 847 from H1688, H23, H460, and H520, respectively). All proteins were assigned a subcellular localization, and 38% were classified as extracellular or membrane-bound. We successfully identified the internal control proteins (also detected by ELISA), kallikrein-related peptidases 14 and 11, and IGFBP2. We also identified known or putative lung cancer tumor markers such as squamous cell carcinoma antigen, carcinoembryonic antigen, chromogranin A, creatine kinase BB, progastrin-releasing peptide, neural cell adhesion molecule, and tumor M2-PK. To select the most promising candidates for validation, we performed tissue specificity assays, functional classifications, literature searches for association to cancer, and a comparison of our proteome with the proteome of lung-related diseases and serum. Five novel lung cancer candidates, ADAM-17, osteoprotegerin, pentraxin 3, follistatin, and tumor necrosis factor receptor superfamily member 1A were preliminarily validated in the serum of patients with lung cancer and healthy controls. Our results demonstrate the utility of this cell culture proteomics approach to identify secreted and shed proteins that are potentially useful as serological markers for lung cancer.Lung cancer is the leading cause of cancer-related mortality worldwide in both men and women. An estimated 213,000 news cases and 160,000 deaths from lung cancer occur in the United States every year (National Cancer Institute). According to the World Health Organization, lung cancers are largely classified into two histologically distinct types, based on the size and appearance of the malignant cells: small cell (SCLC)1 and non-small cell lung cancer (NSCLC). NSCLC, which comprises more than 80% of lung cancers, can be further divided into adenocarcinoma, squamous cell carcinoma, and large cell carcinoma.Despite advances in treatments such as surgery, chemotherapy, and radiotherapy, the clinical outcome for patients with lung cancer still remains poor. The overall 5-year survival rate is only 10–15% (1) mainly because, at the time of diagnosis, most lung cancer patients are at advanced stages. In this context, there is a critical need to detect lung cancer earlier by improving the current diagnostic methods such as computed tomography and chest x-ray and by discovering useful diagnostic and prognostic biomarkers. To date, a number of serum biomarkers for lung cancer have been studied, including CEA, squamous cell carcinoma (SCC)-Ag, neuron-specific enolase, tissue polypeptide antigen, CYFRA21-1 (cytokeratin 19 fragment), and pro-GRP. They are elevated in serum of patients with lung cancer, but they are not sensitive or specific enough, alone or in combination, to reliably diagnose asymptomatic patients with lung cancer.Recently, new approaches in clinical proteomics have been developed to identify novel biomarkers of lung pathology (COPD, asthma, pleural effusion, and cancer) and to gain insights into disease mechanisms in which proteins play a major role. Some proteomics analyses of various biological fluids associated with the human airway have been reported, including nasal lavage fluid (2–4), bronchoalveolar lavage fluid (5, 6), and saliva (7, 8). By using a combination of 2DE analysis and Gel electrophoresis coupled with LC-MS/MS, Nicholas et al. (9) identified 258 proteins in human sputum, and among them, 191 were of human origin. Proteins included lower and upper airway secretory products, cellular products, and inflammatory cell-derived products. In addition, Casado et al. (10) used capillary column LC-ESI-Q/TOF-MS to investigate the proteome profiles of hypertonic saline-induced sputum samples from healthy smokers and patients with COPD of different severity. A total of 203 unique proteins were identified of which some may be markers of COPD severity. The proteomics profile of human pleural effusion from 43 lung adenocarcinoma was also studied using a 2D nano-HPLC-ESI-MS/MS system (11). The results revealed 1,415 unique proteins of which 124 were identified with higher confidence (at least two unique peptide sequences matched). However, there are inherent limitations of using MS for biomarker discovery in complex biological mixtures such as fluids or serum (12, 13), requiring methodologies for depletion of high abundance proteins such as albumin and immunoglobulins. These limitations illustrate the need to find other sources to mine for biomarker discovery.One approach to overcome this limitation posed by complex mixtures is by using a cell culture model, in which cells are grown in serum-free medium, to perform proteomics analysis. This model offers various advantages over the traditional cultures in serum-supplemented medium: it reduces complexity by avoiding interferences from nutritional proteins present in the medium, increases the reproducibility, and allows detection of low abundance proteins. This strategy has been successfully used in our laboratory for the discovery of novel breast and prostate biomarkers (14, 15). This technique was also reported in lung-related proteomics approaches. Tachibana et al. (16) reported the regulatory roles of β1 integrin in morphological differentiation in CADO LC6 cells, an SCLC cell line cultured in serum-free medium. To explore serum biomarkers of lung cancer at early stage, M-BE, an SV40T-transformed human bronchial epithelial cell line with the phenotypic features of early tumorigenesis at high passage, was cultured, and the conditioned medium was used to collect its secretory proteins (17). Proteins secreted from different passages of M-BE cells were extracted and then separated by 2DE followed by MALDI-TOF/TOF mass spectrometry. The authors identified 47 proteins, including cathepsin D, that exhibited increased abundance in culture media or cells during passaging. Moreover, Xiao et al. (18) analyzed the proteins released into the serum-free medium from the tumor microenvironment with short time-cultured lung cancer and adjacent normal bronchial epithelial cells, thus demonstrating the versatility of this approach.In this study, we performed a shotgun proteomics analysis of the conditioned media of four lung cancer cell lines of differing histotypes. Our aim was to identify secreted or membrane-bound proteins that could be useful as novel lung cancer biomarkers. Five proteins were elevated in serum of lung cancer patients, suggesting that they may represent lung cancer biomarkers that are worth validating in the future.     

Identification of Trypanosome Proteins in Plasma from African Sleeping Sickness Patients Infected with T. b. rhodesiense

Control of human African sleeping sickness, caused by subspecies of the protozoan parasite Trypanosoma brucei, is based on preventing transmission by elimination of the tsetse vector and by active diagnostic screening and treatment of infected patients. To identify trypanosome proteins that have potential as biomarkers for detection and monitoring of African sleeping sickness, we have used a ‘deep-mining” proteomics approach to identify trypanosome proteins in human plasma. Abundant human plasma proteins were removed by immunodepletion. Depleted plasma samples were then digested to peptides with trypsin, fractionated by basic reversed phase and each fraction analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This sample processing and analysis method enabled identification of low levels of trypanosome proteins in pooled plasma from late stage sleeping sickness patients infected with Trypanosoma brucei rhodesiense. A total of 254 trypanosome proteins were confidently identified. Many of the parasite proteins identified were of unknown function, although metabolic enzymes, chaperones, proteases and ubiquitin-related/acting proteins were found. This approach to the identification of conserved, soluble trypanosome proteins in human plasma offers a possible route to improved disease diagnosis and monitoring, since these molecules are potential biomarkers for the development of a new generation of antigen-detection assays. The combined immuno-depletion/mass spectrometric approach can be applied to a variety of infectious diseases for unbiased biomarker identification.     

免疫细胞化学方法对胸腔积液中恶性肿瘤细胞的分类与诊断

目的应用免疫细胞化学对胸腔积液中的肺非小细胞癌分类与恶性间皮瘤的鉴别诊断。方法利用液基薄层细胞学自动涂片技术方法对筛查出的胸腔积液可疑瘤细胞及瘤细胞标本1158例进行细胞包埋连续切片,分别作肺非小细胞癌（NSCLC）肿瘤细胞标记物CK7、CK5＆6、TTF-1、E—Ca及恶性间皮瘤标记物MC（MesothelialCell,MC）、CR（Calfetinin,CR）、P53、Vimentin免疫细胞化学染色。结果1158例胸腔积液患者确诊为肺腺癌581例,鳞癌509例,腺鳞癌48例,恶性间皮瘤20例。TTF-1在腺癌中有明显高表达,阳性表达率为92．43％;CK58L6在鳞癌中有明显高表达,阳性表达率为97．45％;MC、CR在恶性间皮瘤中有明显高表达,阳性表达率为100．00％和95．00％。结论液基细胞学与免疫细胞化学技术相结合在胸腔积液鉴别诊断中有很重要的临床意义,CK7、CK58L6、TTF-1、E—ca联合应用可用于胸腔积液中NSCLC之间的分类与诊断,CK58L6、MC、CR、P53、Vimentin联合应用可用于胸腔积液中间皮瘤的定性诊断,值得在临床细胞病理学诊断中推广应用。     

AD-MPE与TPE患者血常规参数变化及其诊断价值

目的:比较结核性胸腔积液(tuberculous pleural effusion,TPE)和肺腺癌性胸腔积液(malignant pleural effusion associated with lung adenocarcinoma,AD-MPE)血常规参数及相关炎症指标的比值,探讨单项指标或联合分析的鉴别诊断价值...     

Advances in proximal fluid proteomics for disease biomarker discovery

Although serum/plasma has been the preferred source for identification of disease biomarkers, these efforts have been met with little success, in large part due the relatively small number of highly abundant proteins that render the reliable detection of low abundant disease-related proteins challenging due to the expansive dynamic range of concentration of proteins in this sample. Proximal fluid, the fluid derived from the extracellular milieu of tissues, contains a large repertoire of shed and secreted proteins that are likely to be present at higher concentrations relative to plasma/serum. It is hypothesized that many, if not all, proximal fluid proteins exchange with peripheral circulation, which has provided significant motivation for utilizing proximal fluids as a primary sample source for protein biomarker discovery. The present review highlights recent advances in proximal fluid proteomics, including the various protocols utilized to harvest proximal fluids along with detailing the results from mass spectrometry- and antibody-based analyses.     

血清和胸水中CA125在结核性和癌性胸水中的表达及临床意义

目的:探讨血清和胸水中CA125在结核性和癌性胸水中的表达及鉴别诊断意义。方法:抽选我院确诊的结核性胸水病人85例(结核组)和癌性胸水病人71例(癌症组),检测两组患者血清和胸水中CA125表达,并以胸水/血清中CA125比值10(p-CA125/s-CA12510)为临界值,观察其对癌性胸水的鉴别特异度、灵敏度及准确性。结果:癌症组胸水中CA125表达及p-CA125/s-CA125比值均显著高于结核组(P0.05);但血清中两组CA125表达比较差异无显著性(P0.05);两组胸水中,以35U/ml为临界值,两组患者阳性率92.9%(79/85)、100%(71/71)比较差异无显著性(X2=7.0718,P=0.0078)。癌症组中p-CA125/sCA125比值10的比率(84.5%VS 17.6%)明显高于结核组(X2=66.6244,P=0.0000);并以其为诊断癌性胸水的临界值,鉴别诊断特异度、灵敏度及准确性分别为82.3%、84.5%、83.3%。结论:血清和胸水中CA125表达对于鉴别结核性或者是癌性胸水的临床意义不大,但是p-CA125/s-CA125比值对于鉴别结核性和癌性胸水具有一定临床价值。     

The value of calretinin and cytokeratin 5/6 as markers for mesothelioma in cell block preparations of serous effusions

Objective: To determine the value of calretinin and cytokeratin (CK) 5/6 in discriminating mesothelioma from adenocarcinoma in serous effusion specimens. Methods: A total of 101 recent, histologically or clinically confirmed malignant effusions with immunostained cell block preparations were reviewed. The cases consisted of 34 mesotheliomas and 67 adenocarcinomas. This included 17 ascitic fluid and 84 pleural fluid samples. The adenocarcinomas included metastatic carcinomas from the breast (12), lung (19), stomach (3), colon (1), pancreas (2), ovary (6) endometrium (1) and 23 histologically confirmed metastases from unknown primary sites. The cases were assessed as negative or positive (>5% of cells stained). The staining pattern was recorded as cytoplasmic, cell membrane, nuclear or cytoplasmic and nuclear staining. Results: Calretinin staining was present in 97% (33/34) of the mesothelioma cases with a majority of them showing both cytoplasmic and nuclear staining (29/33). Only 3% (2/67) of adenocarcinomas were positive for calretinin, one being a lung adenocarcinoma and the other an adenocarcinoma of unknown primary site in an ascitic fluid. Cytokeratin 5/6 staining was also present in 33/34 (97%) of mesothelioma cases. Six (9%) adenocarcinomas were positive, including metastases from the lung (1), breast (1), ovary (2) and unknown primary site (2). Four of the six adenocarcinoma cases positive for CK5/6 were in ascitic fluids. No cases of mesothelioma were negative for both calretinin and CK5/6. Only one adenocarcinoma case, (which was from unknown primary site in an ascitic fluid sample), was positive for both markers. Conclusions: The results confirm that calretinin and CK 5/6 are useful markers for mesothelioma in effusion specimens. CK5/6 staining may be less useful for peritoneal fluid specimens where metastatic adenocarcinomas may be more likely to express the antigen. Further study of ascitic/peritoneal specimens is warranted. However, positive staining, particularly for both antigens, is highly indicative of a mesothelial origin for cells. The two markers make a useful addition to EMA and the panel of adenocarcinoma markers routinely applied to effusion specimens.