Comparison of cell adhesion molecule expression between glioblastoma multiforme and autologous normal brain tissue

Abstract

We investigated glioblastoma multiforme (GBM) for a pattern of consistent alterations in cell adhesion molecules (CAM) expression that might distinguish tumor from normal autologous brain tissue. We used frozen section immunohistochemistry with anti-CAM and computerized image analysis to quantify staining intensity which we expressed as relative intensity units (RIU). Our results showed that normal brain tissue generally did not express α 1 β 1, intercellular CAM-1 (ICAM-1), and sialylated Lewis x, slightly expressed α 2, α 4, α 5, α 6 β 1, α v β 3, lymphocyte function-associated antigen-3 (LFA-3), Lewis x, sialylated LewisLewis x, had a good expression of α 3 β 1 rmand CD44, and strongly expressed neural CAM (NCAM). GBM expressed α 1, α, 3 α 5, α 6 β 1, α v β 3, ICAM-1, LFA-3, CD44, Lewis x, sialylated Lewis x, and sialylated LewisLewis x significantly higher (2-11-fold RIU) than normal brain tissue. ICAM-1 and LFA-3 were the most distinctive markers of GBM. The small blood vessel endothelial cells of the normal brain and the GBM showed a few differences. The tumor endothelium expression of α 2 β 1, α 4 β 1, and LFA-3 RIU appeared twice higher than in normal endothelium and α 6 β 1 showed an average of 40% RIU decrease in comparison to normal. These results show that the expression of several CAM is consistently altered in GBM and its microvasculature when compared with autologous normal brain tissue.