NK activating receptors recognize stress molecules (e.g., MIC-A/B and UL16-binding protein 1-4, ULBP1-4, recognized by NKG2D and CD112 and CD155 recognized by DNAM-1) upregulated on many tumor cells and trigger tumor targeting,50, 51, 52 while NK inhibitory receptors recognize matched “self” major histocompatibility complex (MHC) molecules and suppress tumor killing.53 Here, CD226 is linked to neoplasm.