There are many activating receptors expressed by NK cells, and some examples of relevance to cancer immunotherapy include NKp46, NKp30, DNAM-1 (CD226), 2B4 (CD244), activating KIR, NKG2D, NKG2C, and NKp44 [2, 3, 13, 14]. Here, NCR3 is linked to cancer.