Featured protein analysis of intracranial aneurysms with label-free quantitative mass spectrometry and bioinformatics

Abstract

Objective To investigate the mechanism of development and rupture of intracranial aneurysm (IA) on the protein level and to search for target protein. Methods Specimens were collected from 3 cases of IA undergoing microsurgical clipping and STA (superficial temporal artery) in 3 cases as controls undergoing craniotomy through pterional approach from October 2015 to May 2016 at Department of Neurosurgery, Huashan Hospital Affiliated to Fudan University. All those samples were analyzed by bioinformatics and proteomics. The GO (gene ontology) analysis was performed for study of biological process, cell component and molecular function. PPI (protein-protein interaction) and KEGG (Kyoto Encyclopedia of Genes and Genomes) were used to analyze pathway and differentially expressed proteins. Results Compared between the IA and STA groups, there were 106 differentially expressed proteins identified. Among them, 20 were significantly dysregulated including 6 down-regulated proteins and 14 up-regulated ones. The GO analysis showed that differentially expressed proteins in IA group were mainly related to cellular biosynthetic process, and membrane-bounded organelles represented the most significant cellular structural difference between the IA and STA groups. Further analysis through PPI and KEGG pathway showed that the most significantly up-regulated protein was THBS4, which played a key role in extracellular matrix interaction; and the most significantly down-regulated protein was PTGS1, which was important for platelet activation. Conclusions Label-free quantitative mass spectrometry and bioinformatics could be effective ways to analyze the proteins in IA tissues. THBS could be a key protein in IA progression and a potential target for intervention. Key words: Intracranial aneurysm; Label-free; Proteomics; Computational biology