Project description:Diagnosis of malignant pleural mesothelioma (MPM) is difficult, the most common differential diagnosis being benign pleural diseases and metastatic adenocarcinomas. In order to identify novel markers able to improve diagnostic accuracy, we performed a genome-wide gene expression analysis on tumor cells lines established from pleural effusions (13 MPM and 4 lung adenocarcinoma). Our microarray analysis led to the identification of genes encoding novel cellular and soluble markers whose expression was validated by RT-qPCR. Immunohistochemical staining of tumor biopsies with anti-type-III collagen antibodies were positive in mesothelioma cells but not in adenocarcinoma cells. Using ELISA, we showed that the C-C motif chemokine 2 (CCL2) concentration was significantly higher in pleural effusions from patients with mesothelioma (n = 61) than in subjects with adenocarcinoma (n = 25) or with benign pleural effusions (n = 15): median (interquartile range) = 2.99 ng/mL (1.76-6.01) versus 0.99 ng/mL (0.51-1.83) and 1.47 ng/mL (0.80-1.56), respectively, P < 0.0001. Conversely, the galectin-3 concentration was lower in mesothelioma: 11.50 ng/mL (6.73-23.53) versus 24.74 ng/mL (20.42-70.35) and 17.64 ng/mL (14.81-24.68), respectively, P < 0.0001. The AUC for CCL2 were 0.8030 and 0.7716 for differentiating mesothelioma from adenocarcinoma or benign effusions, respectively. Similarly, the AUC obtained for galectin-3 were 0.7980 and 0.6923, respectively. In conclusion, type-III collagen, CCL2 and galectin-3 are promising new diagnostic markers for mesothelioma.
Project description:Malignant pleural mesothelioma (MPM) is an asbestos-related lethal malignancy refractory to conventional therapies. Since its symptoms are not specific, MPM can be easily confused with other chest diseases, especially metastatic lung adenocarcinomas (ADCA), and diagnosis is often established late when the disease is at an advanced stage. Classically, a reliable diagnosis requires histological analysis of multiple pleural biopsies. However, there is still no absolute marker for MPM. Thus, with the aim of identifying novel markers with higher specificity and sensitivity, gene expression profiling studies have been conducted using tumor specimens. Because of the cell heterogeneity of tumor samples, we decided to apply counterflow centrifugal elutriation to isolate cancer cells from pleural effusions, which are a common feature of MPM and ADCA. We profiled a total of 54 biological samples corresponding to triplicates of 13 MPM and 4 ADCA as well as the SV40-immortalized cell line MeT-5A. Our microarray results confirmed some of the existing markers which are currently used to distinguish MPM from ADCA by immunostaining of pleural biopsies and which have also been proposed for use in a PCR-based assay. Of particular interest, we also identified novel cellular markers (including predominantly COL3A1, OSAP, OCIAD2, XAGE1), which we validated by real time RT-PCR, and novel soluble markers, such as osteonectin and galectin-3, whose clinical utility as molecular targets remains to be determined. Keywords: cell type comparison three-condition experiment: ADCA vs MPM vs Met5A cells 13 MPM, 4 ADCA and Met5A were independantly grown and harvested 3 biological replicates per cell line, one replicate per array
Project description:The goal of our study was to molecularly dissect mesothelioma tumor pathways by mean of microarray technologies in order to identify new tumor biomarkers, that could be used as early diagnostic markers and possibly as specific molecular therapeutic targets. We performed Affymetrix U133A plus 2.0 microarray analysis comparing 9 human pleural mesotheliomas with 4 normal pleural specimen. Stringent statistical feature selection detected a set of differentially expressed genes that were further evaluated to identify potential biomarkers to be used in early diagnostics. Selected genes were confirmed by RT-PCR. As reported by other mesothelioma profiling studies, most of genes are involved in G2/M transition. Our list contains several genes previously described as prognostic classifier. Furthermore, we found novel genes never associated before to mesothelioma and could be involved in tumor progression. Notable, the identification of MMP-14, a member of matrix metalloproteinase family. This molecule has been described as a new disease marker and could be used as biomarker also for mesothelioma early diagnosis and prognosis and that can be viewed as new and effective therapeutic target to test. Accepted for pubblication in PLoS ONE Experiment Overall Design: 9 mesothelioma mixed type tumors versus the pleura of 4 normal donors were compared
Project description:We screened pleural effusion proteomes of mesothelioma and lung adenocarcinoma patients to identify novel soluble mesothelioma biomarkers. We performed quantitative mass spectrometry-(MS-) based proteomics using isobaric tags for relative and absolute quantification (iTRAQ) and used narrow range immobilized pH gradient/high resolution isoelectric focusing (IPG/HiRIEF; pH 4 to 4.25) prior to analysis by nano liquid chromatography-coupled MS/MS. Pleural effusions from patients with malignant mesothelioma (n=6), lung adenocarcinoma (n=6), or benign mesotheliosis (n=7) were analyzed, and more than 1,300 proteins were identified.