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Vascular endothelial growth factor (VEGF) is a homodimeric, disulfide-linked glycoprotein which exhibits endothelial cell-specific mitogenic properties. VEGF is also a potent inducer of vascular permeability. There is considerable experimental evidence that VEGF isoforms are strongly involved in provoking neoplasia-related neoangiogenesis and, consequently, the growth and progression of primary neoplasms (e.g. astrocytic gliomas), a process involving the development of an invasive and metastatic immunophenotype (IP). During the present immunohistochemical study, we observed the expression and tissue localization of VEGF121 employing a specific monoclonal antibody in anaplastic, high-grade astrocytomas (ASTRs) and in glioblastoma multiformes (GMs). We used a sensitive, four-step, alkaline phosphatase conjugated antigen detection technique. The immunoreactivity demonstrated a cytoplasmic, cell surface and extracellular matrix localization pattern in more than 90 percent of the tumor cells and surrounding neoplastically transformed regions with high intensity immunoreactivity (++++, A,B) in every high-grade astrocytic glioma tissue. VEGF121 expression was identified mostly within the cytoplasm of tumor cells, suggesting that the high-grade gliomas possess an embryonic, undifferentiated and more malignant cellular IP. Tumor-related neo-angiogenesis and endothelial cell proliferation were also present. It is a well established fact that the great majority of high-grade astrocytic gliomas are incurable using the three classical therapeutic modalities. In the very near future, the development of individualized fourth modality targeted anti-neoplastic treatment strategies will require the molecular biological identification of immunophenotypically distinguishable neoplasm classes, such as the subtypes of ASTRs, so that the biological therapeutic cocktails will not only be individualized to the particular patient, but also to the particular subtype of cancer. The analysis of the expression pattern of VEGF121 is another piece in the puzzle towards a complete immunophenotyping of childhood glioma.

[Proc Amer Assoc Cancer Res, Volume 46, 2005]