Proteomic analysis of vestibular schwannoma: conflicting role of apoptosis on the pathophysiology of sporadic vestibular schwannoma.

Abstract

In this study, we investigated the pathophysiology and mechanism underlying sporadic forms of vestibular schwannoma (VS) by comparing VS tissue with normal nerve tissue using proteomics. Proteomic analysis by two-dimensional electrophoresis and matrix-assisted laser desorption and ionization time-of-flight mass spectrometry facilitates identification and characterization of specific proteins related to the pathogenesis of various diseases. Proteins were extracted from two vestibular nerve specimens and two VS specimens and analyzed in parallel using two-dimensional electrophoresis. We then analyzed 29 spots that were differentially expressed using matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. Upregulated proteins associated with apoptosis were confirmed by Western blot analysis and immunohistochemistry. Twenty-nine proteins showing significant changes in the expression level between VS tissue and normal nerve tissue were identified. Of these, seven proteins were related to apoptosis. Our findings indicate that apoptosis is associated in a complex manner with the pathophysiology of VS. The suppression of apoptosis is presumably involved in tumor occurrence and, conversely, increased apoptotic expression may contribute to the slow tumor growth rate and may be correlated with the Antoni type B area.