Proteomic analysis of human pleural effusion

Abstract

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.

N-glycoprotein profiling of lung adenocarcinoma pleural effusions by shotgun proteomics

“…This subproteome profile partly overlaps with the data of Tyan and colleagues who performed a more global proteomic analysis. 15 By using an N-GP capture and shotgun mass spectrometry-based approach, we were able to identify known and novel potential biomarkers. We chose pleural effusions because a longer secretion period can be expected in comparison to plasma and especially focused on tumor progression or metastasis-related proteins with the rationale that such proteins may be detected later in the blood plasma of pT1 patients.…”

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

“…Previous proteomics studies [14,15] indicate a high level of similarity between plasma and pleural effusion, hence the same sample collection, sample preparation and analytical methods that are applied to plasma should be applicable when analyzing pleural effusion and, in addition, hold the same advantages. The high presence of coagulatory proteins identified in pleural effusion demonstrated in this study further supports this.…”

“…Several proteomics techniques have been applied previously to detect markers of lung cancer using plasma and pleural effusion as starting material [10][11][12][13][14][15]. However, as of today, no biomarkers have reached the clinic.…”

Protein tyrosine phosphatase non-receptor type 14 is a novel sperm-motility biomarker

“…The in-gel digestion, MS analysis, and database search were performed as described previously with some modifications [29]. The protein spots were excised from the gel and washed twice with 50% acetonitrile and 50% acetonitrile containing 25 mM ammonium bicarbonate.…”