TMA Analysis of Invasive and Non-Invasive Meningiomas.
Fateme Salehi, Shahrzad Jalali, Kelly Burrell, Gelareh Zadeh, Sidney Croul. University Health Network, Toronto, ON, Canada
Background: The pathogenesis of meningioma bone invasion remains unknown. Osteopontin, matrix metalloproteinase's (MMPs), and integrins (ITG) have been found to play a role in bone infiltration in solid tumors including breast and prostate carcinomas. We investigated immuno expression of these proteins in bone invasive and non-invasive meningiomas using the high throughput tissue microarray (TMA) method.
Design: Clinical and Pathologic data was collected on 57 patients with invasive (IM) and non-invasive (NIM) meningiomas. TMA was generated and immunohistochemical analysis for osteoponin, integrin-beta-1 (ITG-b1) and matrix metalloproteinase-2 (MMP-2) performed. Microscopic evaluation of included scoring immunostaining intensity and percentage in tumor and vascular endothelial cells.
Results: MMP-2, OPN, and ITG-b1 immunoreactivity was cytoplasmic and/or membranous, with ITG-b1 being predominantly membranous in endothelial vessel and tumor cells, and OPN being mostly membranous in endothelial cells.ITG-b1: ITG-b1 expression exhibited a striking concentric perivascular pattern in some meningiomas. Tumor cell immunoreactivity was significantly higher in invasive transbasal meningiomas than NIM ones (p = 0.0356). There was a correlation between ITG-b1 and OPN immunoexpression (R=0.4, p=0.03). OPN: Immunoexpression was significantly higher in invasive transbasal meningiomas compared to NIM meningiomas (p = 0.05).MMP-2: Non-invasive transbasal meningiomas exhibited higher MMP-1 immunoexpression in vascular endothelial cells compared to invasive meningiomas (p = 0.0079).
Conclusions: We have demonstrated key differentially expressed proteins between IM and NIM that may lead to greater understanding of the biological substrate for invasive behavior in these tumors.
Tuesday, March 1, 2011 1:00 PM
Poster Session IV # 238, Tuesday Afternoon