Relationship Of Microvessel Parameters And VEGF Expression And 3D Distribution Of CD34 Positive Cells In Human Astrocytomas

Astrocytomas are the most common brain tumors, which are characterized by invasive growth and active angiogenesis. Antiangiogenesis, a new strategy for treatment of astrocytomas depend on better understanding of angiogenesis. It is known that angiogenesis results from an imbalance of proangiogenic and antiangiogenic factors. One of the most important regulatory factors is vascular endothelial growth factor (VEGF), which can induce the migration, proliferation and differentiation of endothelial cells or their progenitors. Most of the results of relationship between expression of VEGF and grades of astrocytomas were from qualitative or semiquantitative analysis, therefore, further quantitative studies are needed.We defined the concept of tumor microvascular architecture phenotype heterogeneity (T-MAPH) as heterogeneities of the density, morphology, structure and the three-dimensional distribution of newly formed vessels in a tumor and between tumors. The pattern of T-MAPH may represent the invasiveness of the tumor therefore predict the outcome of therapy. The 3D distribution of CD34 positive cells is a basis of the understanding for T-MAPH.In the present study, we constructed the tissue microarray, or tissue chip, containing different grades of human astrocytomas with different architecture features of microvessels for the usage of quantitative analysis of microvessel parameters and the expression of VEGF. The main results and conclusions are as follows:1. A tissue microarray composed of 168 points was constructed with human astrocytoma tissues. The microarray includes different grades of astrocytoma with different microvessel types, such as sinusoid, thick-wall and glomeruliod microvessels, etc.