432. Characterization of a Novel Oncolytic Measles Virus Retargeted Against the Urokinase Receptor: In Vitro and In Vivo Studies

Objective. The Edmonston vaccine strain of measles virus (MV- Edm) is a novel oncolytic agent with potent in vitro and in vivo antitumor activity. In order to improve viral tumor specificity, suitable targets need to be identified. The |[ldquo]|ideal|[rdquo]| target for an oncolytic virus should be biologically relevant, overexpressed in tumor compared to normal cells, and preferably overexpressed by tumor stroma, to amplify the virus' antitumor effects. To test the retargeted virus' effects in appropriate syngeneic models, it should be relevant for murine tumors. The urokinase receptor (uPAR) is a biologically validated tumor and stromal target that has been associated with an aggressive tumor phenotype in several cancer types. Our goals are to determine if uPAR is a suitable target for MV oncolytic virotherapy in human and mouse cancer models.