IGFBP-2 expression, angiogenesis and pseudopalisades in glioblastoma

Abstract

Glioblastoma is the most frequent, the most malignant and the best vascularised primary brain tumor. Substantial evidence suggests that IGFBP-2 (insulin-like growth factor binding protein) may play a significant role in the development and progression of various types of cancer, including the anaplastic progression of astroglial tumors. The correlation of IGFBP-2 and VEGF over-expression in diffuse gliomas and strong IGFBP-2 immunostaining and co-expression with VEGF in the cells of pseudopalisading necrosis suggests the induction of IGFBP-2 expression by hypoxia and/or possible involvement of its protein product in angiogenesis. The aim of this study was to analyze the expression of IGFBP-2 and the relationship between the IGFBP-2 expression, extent of bizarre angiogenesis and the presence of pseudopalisades. The prognostic impact of these variables was estimated, as well. Our results revealed that most glioblastoma (75%) express IGFBP2 and that IGFBP2 expression was associated with the presence of pseudopalisading necrosis as well as extensive bizarre angiogenesis. IGFBP-2 immunoreactivity in more than 5% of tumor cells and the presence of pseudopalisading necrosis were prognostically significant in univariate analysis (p=0.034) while in multivariate analysis only a patient's age and the presence of pseudopalisades remained statistically significant (p=0.004). The results of our study showed the association of IGFBP-2 expression in glioblastoma with pseudopalisades and bizarre angiogenesis thus confirming on morphological grounds presumed induction of this gene under hypoxic conditions and its possible role in angiogenesis. © Versita Sp. z o.o.