CD274 and neoplasm: Dually tasked with effector and regulatory functions, the NK cell is the linchpin of the complex immune response: directly responsible for lysis of tumor cells through ADCC and the clearance of MHC-compromised cells in the primary immune response and priming of the tumor microenvironment through PD-L1 induction on tumors and recruitment of DCs and subsequently T cells for the secondary adaptive immune response.