The Advantages and Challenges of CAR-NK Cell Therapy in Overcoming Solid Tumors

In the past few years, cell-based immunotherapy has made significant progress in treating tumors, especially CAR-T cell therapy, which has shown significant efficacy in hematological tumors. However, in the field of solid tumors, it faces limitations such as high toxicity and side effects, an immunosuppressive microenvironment, and limited tumor infiltration. NK cells possess natural killing and recognition mechanisms, resulting in fewer toxic side effects. Therefore, CAR-NK therapy has become a new research direction for solid tumors and is expected to become a substitute for CAR-T therapy. However, this treatment is in its early stage of development and faces problems such as insufficient persistence, immunosuppressive tumor microenvironment, and a lack of standardized production processes. This review summarizes the latest topics and exploratory projects on CAR-NK cell therapy, elucidates its therapeutic mechanism, emphasizes its advantages and challenges, suggests prospective solutions for various challenges and finally discusses the future prospects of it. In order to advance this treatment method towards clinical application, challenges such as NK cell persistence must be addressed. Technologies like gene editing and combination therapies are being employed to gradually overcome current limitations.