iTRAQ technology for differentially expressed proteins screening in dysembryoplastic neuroepithelial tumor and low grade glioma

Objective To screen differentially expressed proteins in dysembryoplastic neuroepithelial tumor(DNT) and low grade glioma(LGG) by the proteomics analysis using isobaric tags for relative and absolute quantification(iTRAQ) combined with liquid chromatography-tandem mass spectrometry(LC-MS/MS). Methods The fresh frozen solid tissues of DNT(6 cases) and LGG(6 cases) were sampled and mixed.Then the protein extraction from admix specimens,protein concentration measurement (Bradford),SDS electrophoresis,protein enzymolysis,iTRAQ mark,SCX,2D and LC-MS/MS were performed to get the data.The MS/MS data were searched against the International UniProt-Human using the Mascot 2.3.02 for peptide identification and quantification.According to protein abundance,differentially expressed proteins were determined when difference was more than 1.3 times and P<0.05. Results Total 88 differentially expressed proteins were identified between DNT and LGG in China Yellow.44 proteins were significantly up-regulated(>1.3-fold) and also 44 were significantly down-regulated.These proteins had different of biologic activity and participated many metabolisms and signal pathways.The important proteins include aquaporin 1,serine/threonine-protein kinase,chloride intracellular channel 1,annexin A1,glutamine synthetase,chondroitin sulfate proteoglycan 4,S100A9,S100A16,S100A13,isocitrate dehydrogenase and so on. Conclusion The differentially expressed proteins of DNT and LGG identified by proteomic analysis using iTRAQ are reliable.The iTRAQ technology can provide a good platform to identify moresignificant molecule difference biomarkers of DNT and LGG.