Abstract
Natural killer (NK) cells play a crucial role in the innate immune system. Unlike adaptive immune cells that rely on specific antigen receptors, NK cell activity is governed by germline-encoded activating or inhibitory receptors expressed on the cell surface. The integration of signals from these receptors determines the NK cell response. Activated NK cells demonstrate potent cytotoxicity against target cells. The distinctive attributes of NK cells, marked by quick response, robust cytotoxicity, and the absence of antigen receptors, position them as promising tools in cancer immunotherapy. Ongoing clinical trials are actively assessing NK cells and related reagents, showing promising outcomes. However, significant challenges arise from the immunosuppressive mechanisms within the tumor microenvironment, impeding the broader application of NK cells. In-depth studies on these mechanisms are imperative to identify solutions, ultimately paving the way for the widespread clinical utilization of NK cells in cancer immunotherapy.