Natural Killers: Targeting NK Cells in Cancer Immunotherapies

Natural Killer (NK) cells are innate lymphoid immune cells that have garnered attention for their pivotal role in tumor surveillance and their ability to recognize and clear cancerous cells. NK cells' delicate balance of activating and inhibitory receptors and those receptors' engagement with target cancer cells determines their effector function. NK cells show promise in the treatment of solid and hematologic tumors. Additionally, targeting NK cells to clear cancerous cells offers advantages over CD8+ T cells, such as not relying on major histocompatibility complex (MHC) I. Successful use of NK cell therapies does have challenges that must be overcome. Several strategies include the use of monoclonal antibodies, chimeric antigen receptor (CAR) NK cell therapy, bi- and tri-specific killer engagers (BiKES and TriKES), and immune checkpoint molecules.