Abstract 1288: Molecular features of endothelial cells isolated from benign and malignant prostatic tissues
Authors: Deeb Kristin K. , Liu Song , Luo Wei , Karpf Adam R. , Morrison Carl , Johnson Candace S. , Trump Donald L. 
Published: February 2011

Abstract
Understanding the genetic pathways that distinguish prostate tumor endothelium from normal endothelium is critical to developing new therapies that better target tumor vasculature. Based on their molecular expression profiles, tumor vasculature expresses markers different from those derived from normal vasculature. In this study, we developed a technique using CD31 Dynabead® positive selection and fluorescence activated cell sorting to isolate endothelial cells (ECs) from benign and malignant tissues derived from prostate surgical specimens. Tumor-derived ECs and benign-derived ECs showed &gt;90% enrichment in primary culture and demonstrated microvascular endothelial cell characteristics such as cobblestone morphology in monolayer culture, diI-acetyl-LDL uptake and capillary-tube like formation in Matrigel®. In vitro primary cultures of the benign-derived and tumor-derived ECs maintained expression of the androgen receptor and endothelial markers such as CD31, von Willebrand factor, intercellular adhesion molecule, vascular endothelial growth factor receptor 1, and vascular endothelial growth factor receptor 2 but expressed neither prostate-specific antigen nor pan-cytokeratin. Expression profiles from tumor-derived ECs and benign-derived ECs were analyzed to identify distinct molecular features. Microarray gene profiling using the Affymetrix GeneChip® Human Genome U133A 2.0 were performed on 5 matched benign-derived and tumor-derived ECs samples and analyzed by comparing the expression profiles of tumor-derived ECs to that of benign-derived ECs using empirical Bayes moderated t-test. Tumor-derived ECs demonstrated 257 differentially expressed genes (DEGs, P &lt; 0.05) of which 86 were up-regulated and 63 were down-regulated by at least 1.5-fold difference compared to benign-derived ECs. Both principal component analysis and hierarchical clustering classified the samples based on the expression profiles of identified DEGs. Gene Ontology analysis revealed that the genes expressed in tumor-derived ECs were enriched for proteases (MMP14, MMP19, PRSS3), transcription factors and regulators (FOXO4, HIF3A, KLF4), cell-cell signaling molecules (SFRP1, PTPRO, CD53, THBS1) and kinases (EPHA5). The identified DEGs were further validated independently by real-time RT-PCR analyses. Isolated endothelial cells from prostate tumor specimens and benign specimens may be useful tools to study prostate tumor vessel properties. This study elucidates some of the molecular features of the prostate tumor endothelium compared to endothelium from benign areas. Identification of genes that are involved in the formation of blood vessels in prostate cancer can be potentially exploited therapeutically. Supported by grants from NIH/NCI CA095045, ACS and RPCI Alliance Foundation.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1288.