NECTIN4 and neoplasm: The attenuated measles virus (MV Edmonston strain) uses the CD46 receptor, which is a regulator of complement activation that is universally expressed in all nucleated human cells but is often overexpressed in tumor cells.53 MV Edmonston strain can kill cells that overexpress this receptor without significant cytopathic effect against nontransformed cells expressing low receptor levels.54 Nectin 4 has been identified as the additional receptor for MV.19 It is a member of adhesion receptors of the immunoglobulin super-family localized to the adherents’ junctions of epithelial cells.