This phenomenon, first characterized for aggressive melanoma cells and named vasculogenic mimicry, illustrates a paradigm of tumor cell plasticity. Accordingly, our main objective was to study the implication of ADAMTS1 in the formation of pseudo-vascular channels in both melanoma and sarcoma settings. We demonstrated its mRNA and protein expression in aggressive Ewing sarcoma and melanoma cell lines that formed vascular-like structures in 3D-cultures. We also studied the presence of specific substrates of ADAMTS1 in these

cell lines. In addition we approached xenograft assays using HT1080 fibrosarcoma cells, negative for ADAMTS1, which were properly modified to study the functional role of this protease. After the subcutaneous injection of these cells in Nu/Nu Balb/c mice, we observed that ADAMTS1 overexpression altered tumor VX-765 nmr growth rate and induced the appearance of vascular-like structures together with the overexpression of endothelial-specific genes, such as VE-Cadherin. Currently we are characterizing the phenotypic properties of both sarcoma and melanoma

cells and its alteration by the protease ADAMTS1. Our work appears in accordance with recent reports that suggest the essential role of extracellular matrix remodeling for tumor plasticity and it provides new insights behind the concept of cancer stem cells. Poster No. 31 Analysis of Transcriptome of Breast Epithelial and Stromal Matched Components

AZD6244 order Isolated by Laser Capture Microdissection Patricia Bortman Rozenchan 1 , Rosimeire Aparecida Roela1, Maria Lúcia Hirata Katayama1, Dirce Maria Carraro2, Elisa Napolitano e Ferreira2, Cynthia Aparecida Bueno de Toledo2, Fernando Augusto Soares2, Maria Aparecida Azevedo Koike Folgueira1, Maria Mitzi Brentani1 1 Laboratório de Oncologia Experimental, Departamento de Radiologia, Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP, Brazil, 2 Centro de Ensino e Pesquisa, Hospital A.C. Camargo, São Paulo, SP, Brazil The microenvironment on which tumors grow is complex Rucaparib molecular weight consisting mainly of tumor epithelial cells and associated fibroblasts as well as non transformed epithelial cells, normal fibroblasts and also endothelial and immune cells. The exact role of these cell types, Stattic interacting with each other, in the progression of breast cancer has yet to be fully understood. One approach to study this interaction is to determine changes in gene expression profiles between fibroblasts and non-malignant or malignant breast epithelial cells, evaluated separately. Previously, we have demonstrated changes in differential expression profiles of mammary epithelial cells and fibroblasts in a co-culture model; herein we attempt to show these interactions by removing each cell type directly from the respective tissue.