KLRK1 and neoplasm: Tumor shedding of NKGD ligands (i.e. sMICA) provide a means by which the tumor can escape immune surveillance; the predominant form of this type of escape involves reduced NKG2D expression on the surface of circulating blood lymphocytes (e.g. NK and CD8+ T cells), resulting in attenuated recognition of malignant cancer cells and reduced tumor surveillance [19].