PVR and neoplasm: This enhanced interaction can be attributed to the expression of tumour-associated ligands on MDA-MB-231 cells, including CD155 and Nectin-2 (ligands for DNAM-1)100,101, B7-H6 (NKp30 ligand),102 and ULBP-4 (NKG2D ligand)103 for MDA-MB-231 cells, as reported in the literature.