Interestingly, HCC cells express ligands of several activating NK receptors (NKR), including NKp30, natural killer receptor group 2, member D (NKG2D) and DNAM-1 such as the B7 protein homolog 6, the major histocompatibility complex class I chain-related protein A and B (MICA/B) and CD155, respectively, whose expression can correlate with the outcome of the disease [5,6]. The gene discussed is PVR; the disease is hepatocellular carcinoma.