Increased Phosphorylation of Vimentin in Noninfiltrative Meningiomas

Abstract

BackgroundTissue invasion or tissue infiltration are clinical behaviors of a poor-prognosis subset of meningiomas. We carried out proteomic analyses of tissue extracts to discover new markers to accurately distinguish between infiltrative and noninfiltrative meningiomas.Methodology/Principal FindingsProtein lysates of 64 different tissue samples (including two brain-invasive and 32 infiltrative tumors) were submitted to SELDI-TOF mass spectrometric analysis. Mass profiles were used to build up both unsupervised and supervised hierarchical clustering. One marker was found at high levels in noninvasive and noninfiltrative tumors and appeared to be a discriminative marker for clustering infiltrative and/or invasive meningiomas versus noninvasive meningiomas in two distinct subsets. Sensitivity and specificity were 86.7% and 100%, respectively. This marker was purified and identified as a multiphosphorylated form of vimentin, a cytoskeletal protein expressed in meningiomas.Conclusions/SignificanceSpecific forms of vimentin can be surrogate molecular indicators of the invasive/infiltrative phenotype in tumors.

The heterogeneity of meningioma revealed by multiparameter analysis: infiltrative and non-infiltrative clinical phenotypes

“…3). This marker was identified as a phosphorylated form of vimentin (32). For quantitative assessment of the amount of the phosphorylated vimentin in 14 tumor samples, the surface of the peak was measured in the spectra.…”

Proteomics and translational medicine: molecular biomarkers for cancer diagnosis, prognosis and prediction of therapy outcome

“…An increased phosphorylation of vimentin appeared to be a discriminative marker for clustering infiltrative and noninfiltrative meningiomas. Sensitivity and specificity were 86.7 and 100%, respectively [13].…”

Proteomic data in meningiomas: post-proteomic analysis can reveal novel pathophysiological pathways

“…Five papers and two abstracts were identified in which differences in multiple protein expression between different subtypes of meningeal neoplasms were described [13][14][15][16][17][18][19]. There was considerable variation regarding aims, methodology, statistical power and use of control tissue between studies within this publication list (Table 1).…”

“…Wibom et al [19] compared proteomes of invasive and infiltrative meningioma versus non invasive or non-infiltrative WHO I meningiomas. Boumrani et al [15] investigated specifically, brain invasive and infiltrative behaviour in mostly WHO I meningiomas. Saydam et al [17] compared findings in meningioma cell lines versus normal arachnoidal tissue.…”

“…One study named only a single protein of interest that they found as an intensity peak in the protein profile adequate in discriminating between non-infiltrative versus infiltrative or invasive tumours. This was a multi-phosphorylated form of vimentin [15]. Another study compared differentially expressed spectra intensities in the protein profiles, without establishing specific protein identification [19].…”