Expression of neural cell-adhesion molecule isoforms and epithelial cadherin adhesion molecules in 47 human meningiomas: correlation with clinical and morphological data.

Meningiomas are derived from arachnoidal cells exhibiting both epithelial and mesenchymal properties. The expression of epithelial cadherin and neural cell-adhesion molecule isoforms was examined in 47 meningioma specimens and normal arachnoid villi by using immunohistochemistry and immunoblot procedures. For immunohistochemistry, the percentage of immunostained surface versus counterstained surface and the intensity of labeling were quantified by image analysis and correlated with clinical and morphological data. Neural cell-adhesion molecule, 140-kDa, was expressed by all meningiomas examined and by cap cells and the fibrous capsule forming the arachnoid villi. Neural cell-adhesion-molecule immunostaining was correlated to tumor location, histological type, and grade. The expression of polysialylated isoforms was related to tumor location and grade, with a higher expression on convexity meningiomas and high-grade tumors. Epithelial cadherin was expressed with various intensity. In arachnoid villi, its expression was restricted to cap cells, but it was found in all meningiomas, whatever their histological type or grade. However, the expression was stronger in whorls and meningiotheliomatous areas versus fibroblastic areas. No correlation was observed with the tumor location or the grade. These data suggest that neural cell-adhesion molecule and epithelial cadherin play a role in the morphogenesis and histogenesis of human meningiomas.