Abstract—Nowadays, immunotherapy plays an important role in the comprehensive treatment of tumors. As an immune cell, Natural Killer (NK) cells have many advantages in tumor immunotherapy and will become a potential tumor immunotherapy. This dissertation will investigate three types of NK cell-based immunotherapies, namely NK cell infusion therapy, immune checkpoint blockade therapy, and CAR-NK therapy. The potential of immunotherapy based on NK cells has been demonstrated in various clinical trial cases. At the same time, it shows that there are still some key questions about NK cells, such as how to prepare NK cells, the selection of NK cell donors, and how to improve the function of NK cells. This article reviews the research progress of NK cell-based immunotherapy, which is expected to provide new ideas for the clinical treatment of tumors.
 

Keywords—CAR-NK, immune checkpoint blockade, NK cell, tumor immunotherapy