PDCD1 and cancer: Additional studies have also confirmed that PD-1/PD(L)1 immunotherapy can elicit NK cell response in several murine cancer models [44], and that the binding of anti-PD(L)1 mAb to PD(L)1+ NK cells was indeed responsible for the modulation of their function, exerting an enhanced cytotoxicity against target cells in a process independent of the PD-1/PD(L)1 axis [56].