PVR and neoplasm: The recognition of CD155 by DNAM-1 potentiates the cytotoxicity of NK cells against a range of tumor cells and has been shown to be critical for tumor immunosurveillance in several murine models [62,63,64], although its significance in immunosurveillance has been controversial as, in some experimental circumstances, the antitumoral effect of DNAM-1 was significant only when the antitumoral response induced by cytokines was analyzed [65].