Proteins associated with the size and expansion rate of the abdominal aortic aneurysm wall as identified by proteomic analysisspi_sup,spii_sup

Abstract

Objective: Identification of biomarkers for the natural history of abdominal aortic aneurysms (AAA) holds the key to non-surgical intervention and improved selection for AAA repair. We aimed to associate the basic proteomic composition of AAA wall tissue with the expansion rate and size in patients with AAA. Methods: A proteomic approach was used, consisting of two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS) to identify differentially expressed proteins in AAA tissue. Relevant protein spots were identified by liquid chromatography-tandem mass spectrometry (LC-MSyMS). Results: Spearman's correlation analysis revealed 16 protein spots were strongly correlated with AAA expansion rate (r)0.75). Nine protein spots were identified. Six protein spots showed correlation with AAA size (r)0.5). Three protein spots were identified: vitronectin with traces of calreticulin, albumin and a spot containing two proteins: collagen a-3(VI) chain and vitamin D binding protein. Interestingly, in our previous study vitronectin was shown to be down-regulated in a ruptured AAA group compared with non-ruptured AAA. Western blot analysis in the present study confirmed a correlation of vitronectin bands with AAA size in aortic aneurysm tissue. Conclusion: A proteomic approach seems valuable, and identified several candidates not previously associated with AAA. Larger studies are required to confirm the potential and clinical role of the identified proteins. © 2010 Published by European Association for Cardio-Thoracic Surgery.