The University of Georgia College of Veterinary Medicine

eorgia Veterinary Scholars Program

GVSP Summer 2007 Scholars

Georgia Veterinary Scholar	Faculty Mentor

Charles Aldridge University of Georgia Class of 2010	Dr. Clifton Baile

Experimental infection of domestic dogs with Ehrlichia ewingii

Apelin Signaling and Angiogenesis in Solid Tumors
Charles Aldridge*, Clifton Baile, Diane L. Hartzell, Srujana Rayalam
University, Agricultural Biotechnology, Athens, Georgia, 30602, USA
Abstract
Apelin signaling is believed to be involved in pathological angiogenesis in a number of diseases including solid tumors and age related macular degeneration. The aim of this project is to test the role of apelin signaling in promoting angiogenesis in solid tumors by establishing that decreases in apelin expression can lead to a reduction in solid tumor growth in a mouse xenograft model, with an associated reduction in angiogenesis. A preliminary hybridization analysis of RNA samples isolated from 154 human solid tumor samples indicated that approximately one third of all tumor samples (60/154) showed apelin upregulation of at least 2 fold relative to matched controls. Apelin and VEGF (a potent angiogenic factor) mRNA expression levels in approximately 20 human tumor cell lines established for xenograft experiments will be evaluated by doing a quantitative PCR analysis with 18s as control. It is likely that tumor cell lines that express significant levels of apelin with moderate to low VEGF will be discovered. These high apelin/low VEGF cell lines will then be injected into nude mice and cohorts of animals will be given an anti-apelin monoclonal antibody at various doses, a control antibody (non-reactive with apelin) or PBS twice weekly. Tumor cells that have been engineered to over-express apelin or VEGF will act as the control. Slowing of tumor growth in animals administered the anti-apelin antibody compared to untreated animals will indicate that apelin signaling does play a significant role in solid tumor growth.