Detection Of Malignant Pleural Mesothelioma Research Articles

Diagnostic and Prognostic Utility of the Extracellular Vesicles Subpopulations Present in Pleural Effusion.

Extracellular vesicles (EVs), comprising exosomes, microvesicles, and apoptotic bodies, are released by all cells into the extracellular matrix and body fluids, where they play important roles in intercellular communication and matrix remodeling in various pathological conditions. Malignant pleural mesothelioma (MPM) is a primary tumor of mesothelial origin, predominantly related to asbestos exposure. The detection of MPM at an early stage and distinguishing it from benign conditions and metastatic adenocarcinomas (AD) is sometimes challenging. Pleural effusion is often the first available biological material and an ideal source for characterizing diagnostic and prognostic factors. Specific proteins have previously been identified as diagnostic markers in effusion, but it is not currently known whether these are associated with vesicles or released in soluble form. Here, we study and characterize tumor heterogeneity and extracellular vesicle diversity in pleural effusion as diagnostic or prognostic markers for MPM. We analyzed extracellular vesicles and soluble proteins from 27 pleural effusions, which were collected and processed at the department of pathology and cytology at Karolinska University Hospital, representing three different patient groups, MPM (n = 9), benign (n = 6), and AD (n = 12). The vesicles were fractionated into apoptotic bodies, microvesicles, and exosomes by differential centrifugation and characterized by nanoparticle tracking analysis and Western blotting. Multiplex bead-based flow cytometry analysis showed that exosomal markers were expressed differently on EVs present in different fractions. Further characterization of exosomes by a multiplex immunoassay (Luminex) showed that all soluble proteins studied were also present in exosomes, though the ratio of protein concentration present in supernatant versus exosomes varied. The proportion of Angiopoietin-1 present in exosomes was generally higher in benign compared to malignant samples. The corresponding ratios of Mesothelin, Galectin-1, Osteopontin, and VEGF were higher in MPM effusions compared to those in the benign group. These findings demonstrate that relevant diagnostic markers can be recovered from exosomes.

Verification of a Blood-Based Targeted Proteomics Signature for Malignant Pleural Mesothelioma.

We have verified a mass spectrometry (MS)-based targeted proteomics signature for the detection of malignant pleural mesothelioma (MPM) from the blood. A seven-peptide biomarker MPM signature by targeted proteomics in serum was identified in a previous independent study. Here, we have verified the predictive accuracy of a reduced version of that signature, now composed of six-peptide biomarkers. We have applied liquid chromatography-selected reaction monitoring (LC-SRM), also known as multiple-reaction monitoring (MRM), for the investigation of 402 serum samples from 213 patients with MPM and 189 cancer-free asbestos-exposed donors from the United States, Australia, and Europe. Each of the biomarkers composing the signature was independently informative, with no apparent functional or physical relation to each other. The multiplexing possibility offered by MS proteomics allowed their integration into a single signature with a higher discriminating capacity than that of the single biomarkers alone. The strategy allowed in this way to increase their potential utility for clinical decisions. The signature discriminated patients with MPM and asbestos-exposed donors with AUC of 0.738. For early-stage MPM, AUC was 0.765. This signature was also prognostic, and Kaplan-Meier analysis showed a significant difference between high- and low-risk groups with an HR of 1.659 (95% CI, 1.075-2.562; P = 0.021). Targeted proteomics allowed the development of a multianalyte signature with diagnostic and prognostic potential for MPM from the blood. The proteomic signature represents an additional diagnostic approach for informing clinical decisions for patients at risk for MPM.

Breath Analysis for Early Detection of Malignant Pleural Mesothelioma: Volatile Organic Compounds (VOCs) Determination and Possible Biochemical Pathways.

Malignant pleural mesothelioma (MPM) is a rare neoplasm, mainly caused by asbestos exposure, with a high mortality rate. The management of patients with MPM is controversial due to a long latency period between exposure and diagnosis and because of non-specific symptoms generally appearing at advanced stage of the disease. Breath analysis, aimed at the identification of diagnostic Volatile Organic Compounds (VOCs) pattern in exhaled breath, is believed to improve early detection of MPM. Therefore, in this study, breath samples from 14 MPM patients and 20 healthy controls (HC) were collected and analyzed by Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC/MS). Nonparametric test allowed to identify the most weighting variables to discriminate between MPM and HC breath samples and multivariate statistics were applied. Considering that MPM is an aggressive neoplasm leading to a late diagnosis and thus the recruitment of patients is very difficult, a promising data mining approach was developed and validated in order to discriminate between MPM patients and healthy controls, even if no large population data are available. Three different machine learning algorithms were applied to perform the classification task with a leave-one-out cross-validation approach, leading to remarkable results (Area Under Curve AUC = 93%). Ten VOCs, such as ketones, alkanes and methylate derivates, as well as hydrocarbons, were able to discriminate between MPM patients and healthy controls and for each compound which resulted diagnostic for MPM, the metabolic pathway was studied in order to identify the link between VOC and the neoplasm. Moreover, five breath samples from asymptomatic asbestos-exposed persons (AEx) were exploratively analyzed, processed and tested by the validated statistical method as blinded samples in order to evaluate the performance for the early recognition of patients affected by MPM among asbestos-exposed persons. Good agreement was found between the information obtained by gold-standard diagnostic methods such as computed tomography CT and model output.

P1.09-001 Multiplexed Biomarker Strategies Based on Targeted Proteomics for Detection of Malignant Pleural Mesothelioma in Blood

P1.09-001 Multiplexed Biomarker Strategies Based on Targeted Proteomics for Detection of Malignant Pleural Mesothelioma in Blood

Abstract 204: In vitro metabolomics of mesothelioma: Challenges and outcomes

Abstract Introduction Early detection of malignant pleural mesothelioma (MPM) is likely to improve outcome in affected patients. From our previous studies (MesoBreath 1 & 2) we developed a screening tool in which volatile organic compounds (VOCs) in breath allowed discrimination of MPM patients from at risk controls. However it is not yet clear which VOCs arise from the neoplastic cells themselves or from the host response. Identifying the cancer cell-specific compounds should increase the specificity of our breathomic signature model. Therefore, we set up an in vitro experimental setup model for VOC analysis from the headspace of mesothelioma cell lines. Methods Standard polystyrene culture flasks (NunclonTM Delta Surface, Thermo Scientific) were mounted with an adapted cap accommodating teflon inlet and outlet tubes. The inlet tube provides environmental air while an external pump (Gilian GilAir Plus, Sensidyne) draws headspace air from the outlet tube over an adsorption column (Tenax GR, Markes International, UK). The adsorption columns were further processed on a GC-MS platform (GC: Focus GC, Thermo Finnigan, Milan, Italy; DSQII Single Quadrupole MS, Thermo Finnigan, Austin, TX, USA). VOC profiles were processed using supervised clustering algorithms and principal component analysis. Results Using this setup, we have investigated the impact of flow and total sampled volume on the concentration and range of VOCs detected. For a constant flow, VOCs were detected in higher concentrations with increasing sample volume. For a constant volume, a lower sampling flow yielded a higher concentration of detected VOCs. Most of the VOCs obtained were alkanes and ketones. We will show data illustrating the differential VOC profiles of container plastic, cell culture medium and growing mesothelioma cancer cells, as well as the differential VOC output of epithelioid vs sarcomatoid mesothelioma cell lines. Conclusions We have succesfully developed an in vitro experimental setup allowing collection and analysis of VOCs emanating from mesothelioma cancer cell line cultures. This platform will allow us to investigate how VOC profiles are impacted in different experimental conditions (e.g. hypoxia, nutrient deprivation, cytostatics, co-culture with leukocytes). The data collected will help us to pinpoint the cancer cell-derived VOCs from patient exhaled breath, and increase the robustness of our mesothelioma breathomic signature. Note: This abstract was not presented at the meeting. Citation Format: Sabrina Lagniau, Kevin Lamote, Lore Vandermeersch, Herman Van Langenhove, Jan P. van Meerbeeck, Karim Y. Vermaelen. In vitro metabolomics of mesothelioma: Challenges and outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 204. doi:10.1158/1538-7445.AM2017-204

Transcriptomic Analysis of the Claudin Interactome in Malignant Pleural Mesothelioma: Evaluation of the Effect of Disease Phenotype, Asbestos Exposure, and CDKN2A Deletion Status.

Malignant pleural mesothelioma (MPM) is a highly aggressive tumor primarily associated with asbestos exposure. Early detection of MPM is restricted by the long latency period until clinical presentation, the ineffectiveness of imaging techniques in early stage detection and the lack of non-invasive biomarkers with high sensitivity and specificity. In this study we used transcriptome data mining in order to determine which CLAUDIN (CLDN) genes are differentially expressed in MPM as compared to controls. Using the same approach we identified the interactome of the differentially expressed CLDN genes and assessed their expression profile. Subsequently, we evaluated the effect of tumor histology, asbestos exposure, CDKN2A deletion status, and gender on the gene expression level of the claudin interactome. We found that 5 out of 15 studied CLDNs (4, 5, 8, 10, 15) and 4 out of 27 available interactors (S100B, SHBG, CDH5, CXCL8) were differentially expressed in MPM specimens vs. healthy tissues. The genes encoding the CLDN-15 and S100B proteins present differences in their expression profile between the three histological subtypes of MPM. Moreover, CLDN-15 is significantly under-expressed in the cohort of patients with previous history of asbestos exposure. CLDN-15 was also found significantly underexpressed in patients lacking the CDKN2A gene. These results warrant the detailed in vitro investigation of the role of CDLN-15 in the pathobiology of MPM.

Detection of malignant pleural mesothelioma in exhaled breath by multicapillary column/ion mobility spectrometry (MCC/IMS)

Malignant pleural mesothelioma (MPM) is predominantly caused by previous asbestos exposure. Diagnosis often happens in advanced stages restricting any therapeutic perspectives. Early stage detection via breath analysis was explored using multicapillary column/ion mobility spectrometry (MCC/IMS) to detect volatile organic compounds (VOCs) in the exhaled breath of MPM patients in comparison to former occupational asbestos-exposed and non-exposed controls.Breath and background samples of 23 MPM patients, 22 asymptomatic former asbestos (AEx) workers and 21 healthy non-asbestos exposed persons were taken for analysis. After background correction, we performed a logistic least absolute shrinkage and selection operator (lasso) regression to select the most important VOCs, followed by receiver operating characteristic (ROC) analysis.MPM patients were discriminated from both controls with 87% sensitivity, 70% specificity and respective positive and negative predictive values of 61% and 91%. The overall accuracy was 76% and the area under the ROC-curve was 0.81. AEx individuals could be discriminated from MPM patients with 87% sensitivity, 86% specificity and respective positive and negative predictive values of 87% and 86%. The overall accuracy was 87% with an area under the ROC-curve of 0.86.Breath analysis by MCC/IMS allows MPM patients to be discriminated from controls and holds promise for further investigation as a screening tool for former asbestos-exposed persons at risk of developing MPM.

Correlation between computed tomography of the chest and medical thoracoscopic findings in primary pleural tumors

Malignant pleural mesothelioma ( MPM) is an aggressive tumor arising from the mesothelial cells lining the pleura. It commonly presents with unilateral pleural effusion with variable degree of pleural thickening and nodularity. MPM usually develops on the parietal pleura, and involvement of the visceral pleura indicates more advanced stage. Treatment of MPM should not be started before correct diagnosis and staging with computed tomography (CT) and thoracoscopy. The aim of this study was to assess the correlation between findings on chest CT and those on thoracoscopy and to evaluate the sensitivity of chest CT to identify malignant pleural lesions. Patients with suspected MPM and indicated for medical thoracoscopy for diagnostic confirmation were enrolled in the present study. Twenty patients with confirmed diagnosis after tissue biopsies with medical thoracoscopy were selected. Comparison and correlation between CT findings and medical thoracoscopic findings were made. Thoracoscopy showed parietal pleural invasion in all patients, whereas noncontrast chest CT showed parietal pleural lesions in 14 patients (70%). Visceral pleural involvement was evident in 13 patients (65%) on thoracoscopy, but chest CT detected only one case (5%) with visceral pleural involvement. Three patients (15%) were found to have fibrous septations on thoracoscopy, compared with only one patient (5%) on chest CT. The sensitivity of noncontrast chest CT in the detection of MPM was 70%. Although the sensitivity of noncontrast chest CT in the detection of MPM is high, thoracoscopy is needed not only to confirm the diagnosis but also to assess the different parts of the pleura and to allow proper staging of the disease. Egypt J Broncho 2014 8:32–37

Early detection of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare tumour. Exposure to asbestos is a well-established aetiological factor for MPM. Patients typically present with shortness of breath due to pleural effusion or chest pain in a more advanced stage. The diagnosis is usually suggested by imaging studies (unilateral pleural thickening; pleural effusion). An occupational history must be obtained. Cytological examination of the effusion can be diagnostic, but often shows equivocal results. Therefore, histology, including immunohistochemistry, is the gold standard. Thoracoscopy, a video-assisted surgical procedure or open pleural biopsy in a fused pleural space may be necessary to provide sufficient material for accurate histological diagnosis. There are three main histological types (epithelial, sarcomatous and mixed) with ~60% being epithelial. Data suggest the possible contribution of serum mesothelin-related proteins and osteopontin along with others as useful markers to support the diagnosis of mesothelioma; however, the precise role of these markers is yet to be defined.

Role of fibulin-3 in the diagnosis of malignant mesothelioma

BackgroundEarly detection of malignant pleural mesothelioma (MPM) is critical to survival, the use of pleural or blood fibuin-3 might allow this early detection. AimStudying the validity of measuring serum and pleural fibulin-3 in the diagnosis of MPM. Subjects & MethodsFibulin-3 levels were measured in serum and pleural fluid by enzyme-linked immunosorbant assay (ELISA) in 45 patients with exudative pleural effusion. Patients with non-conclusive cytology or microbiological examination had undergone medical thoracosope for histopathological examination. ResultsTwenty five was diagnosed as MPM, 11 cases as pleural metastasis of carcinoma (Mets) and nine cases with benign pleural effusions. Patients with MPM had significantly higher pleural effusion and serum fibulin-3 levels than those with metastatic effusion of carcinoma or benign pleural effusion (p-value <0.001). Using a cut-off point of pleural fluid fibulin-3 (150ng/ml) with AUC of 0.878 (sensitivity 72.3%, specificity 80) and at a cut-off point of serum fibulin-3 (66.5ng/ml), with AUC of 0.776 (sensitivity 88%, specificity 81.8%), discrimination between MPM and Mets occurred. Also, using a cut-off point of pleural fluid fibulin-3 (127.5ng/ml) with AUC of 0.909 (sensitivity 88%, specificity 77.8%), and at a cut-off point of serum fibulin-3 (18ng/ml), with AUC of 0.931 (sensitivity 100%, specificity 77.8%), discrimination between MPM and benign pleural effusion could occur. ConclusionsFibulin-3 in the serum and pleural fluid is a good biomarker in the diagnosis of MPM and in differentiation between MPM from malignant pleural metastasis other than mesothelioma and also from benign pleural effusions.

Early Detection of Malignant Pleural Mesothelioma in Asbestos-Exposed Individuals with a Noninvasive Proteomics-Based Surveillance Tool

BackgroundMalignant pleural mesothelioma (MM) is an aggressive, asbestos-related pulmonary cancer that is increasing in incidence. Because diagnosis is difficult and the disease is relatively rare, most patients present at a clinically advanced stage where possibility of cure is minimal. To improve surveillance and detection of MM in the high-risk population, we completed a series of clinical studies to develop a noninvasive test for early detection.Methodology/Principal FindingsWe conducted multi-center case-control studies in serum from 117 MM cases and 142 asbestos-exposed control individuals. Biomarker discovery, verification, and validation were performed using SOMAmer proteomic technology, which simultaneously measures over 1000 proteins in unfractionated biologic samples. Using univariate and multivariate approaches we discovered 64 candidate protein biomarkers and derived a 13-marker random forest classifier with an AUC of 0.99±0.01 in training, 0.98±0.04 in independent blinded verification and 0.95±0.04 in blinded validation studies. Sensitivity and specificity at our pre-specified decision threshold were 97%/92% in training and 90%/95% in blinded verification. This classifier accuracy was maintained in a second blinded validation set with a sensitivity/specificity of 90%/89% and combined accuracy of 92%. Sensitivity correlated with pathologic stage; 77% of Stage I, 93% of Stage II, 96% of Stage III and 96% of Stage IV cases were detected. An alternative decision threshold in the validation study yielding 98% specificity would still detect 60% of MM cases. In a paired sample set the classifier AUC of 0.99 and 91%/94% sensitivity/specificity was superior to that of mesothelin with an AUC of 0.82 and 66%/88% sensitivity/specificity. The candidate biomarker panel consists of both inflammatory and proliferative proteins, processes strongly associated with asbestos-induced malignancy.SignificanceThe SOMAmer biomarker panel discovered and validated in these studies provides a solid foundation for surveillance and diagnosis of MM in those at highest risk for this disease.

Association of MiR-126 with Soluble Mesothelin-Related Peptides, a Marker for Malignant Mesothelioma

BackgroundImproved detection methods for diagnosis of malignant pleural mesothelioma (MPM) are essential for early and reliable detection as well as treatment. Since recent data point to abnormal levels of microRNAs (miRNAs) in tumors, we hypothesized that a profile of deregulated miRNAs may be a marker of MPM and that the levels of specific miRNAs may be used for monitoring its progress.Methods and ResultsmiRNAs isolated from fresh-frozen biopsies of MPM patients were tested for the expression of 88 types of miRNA involved in cancerogenesis. Most of the tested miRNAs were downregulated in the malignant tissues compared with the normal tissues. Of eight significantly downregulated, three miRNAs were assayed in cancerous tissue and adjacent non-cancerous tissue sample pairs collected from 27 formalin-fixed, paraffin-embedded MPM tissues by quantitative RT-PCR. Among the miRNAs tested, only miR-126 significantly remained downregulated in the malignant tissues. Furthermore, the performance of the selected miR-126 as biomarker was evaluated in serum samples of asbestos-exposed subjects and MPM patients and compared with controls. MiR-126 was not affected by asbestos exposure, whereas it was found strongly associated with VEGF serum levels. Levels of miR-126 in serum, and its levels in patients' serum in association with a specific marker of MPM, SMRPs, correlate with subjects at high risk to develop MPM.Conclusions and SignificanceWe propose miR-126, in association with SMRPs, as a marker for early detection of MPM. The identification of tumor biomarkers used alone or, in particular, in combination could greatly facilitate the surveillance procedure for cohorts of subjects exposed to asbestos.

Early detection of malignant pleural mesothelioma through measurement of soluble mesothelin‐related protein and positron emission tomography

A 51-year-old man with no known history of asbestos exposure presented with hydropneumothorax. Soluble mesothelin-related protein testing and combined positron emission tomography and computed tomography were used to diagnose malignant pleural mesothelioma. One year after radical surgery and radiotherapy, there was no clinical recurrence.

95 POSTER A comparative analysis of megakaryocyte potentiating factor and mesothelin as serum markers for the detection of malignant pleural mesothelioma

95 POSTER A comparative analysis of megakaryocyte potentiating factor and mesothelin as serum markers for the detection of malignant pleural mesothelioma

The role of new imaging techniques in diagnosis and staging of malignant pleural mesothelioma.

This review highlights the different imaging modalities for the detection of malignant pleural mesothelioma. The chest film is the initial diagnostic tool of choice because it is easy to perform, inexpensive, and widely available. Unfortunately, it demonstrates malignant pleural mesothelioma in later stages of disease and is not suitable for an early sensitive and specific diagnosis. Computed tomography is capable of distinguishing the different forms of pleural abnormalities. The knowledge of computed tomography findings is important for differentiation of malignant pleural diseases from benign diseases. Contrast-enhanced magnetic resonance imaging in three planes can be clinically useful to differentiate pleural mesothelioma from other malignancies or from benign pleural diseases. Furthermore, magnetic resonance imaging offers the possibility to differentiate invasion of the diaphragm from transdiaphragmatic tumor growth, and, in patients who are surgical candidates and who have questionable areas of local tumor extension on computed tomography, magnetic resonance imaging may provide additional information to plan or avoid surgery. Improvements in the detection of regional and distant metastases are needed to identify patients most likely to benefit from aggressive combined modality treatment regimes. In this context, positron emission tomography is a metabolic imaging technique that offers the possibility to evaluate active malignant cells. Drawbacks to this technique include false-positive findings, which may occur at sides of inflammation, and lesser anatomic detail information. A complete and accurate staging of malignant pleural mesothelioma is essential to evaluate the efficacy of new therapeutic strategies. This implies the need to be familiar with the most recently developed staging system from the International Mesothelioma Interest Group.

Malignant pleural mesothelioma: US-guided histologic core-needle biopsy.

To assess the clinical use of ultrasonographically (US) guided core-needle biopsy, performed with a one-hand automatic sampling technique, in the diagnosis of malignant pleural mesothelioma (MPM). The authors reviewed the findings in 70 patients with a tentative diagnosis of MPM who underwent US-guided core-needle biopsy at our institution during the past 10 years. Fifty-two of the 70 patients who underwent automatic high-speed core-needle biopsy at our institution had MPM; 18 had other disorders. The correct diagnosis was made in 56 patients. Twelve of 14 inadequate biopsy specimens were false-negative for MPM. There were no false-positive biopsy results. In the detection of MPM, US-guided core-needle biopsy had a sensitivity of 77%, specificity of 88%, accuracy of 80%, positive predictive value of 100%, and negative predictive value of 57%. There were no serious complications. US-guided core-needle biopsy is highly effective in the diagnosis of MPM. Owing to its simplicity, low cost, and few side effects, it could be the biopsy method of choice for detection of this condition.