Precision sniper for solid tumors: CAR-NK cell therapy

Chimeric antigen receptor (CAR) represents a novel targeted therapy that uses genetic engineering to modify effector cells for precise tumor cell targeting. Chimeric antigen receptor-T (CAR-T) cell immunotherapy, which employs T cells as effectors, has demonstrated significant efficacy in treating hematologic malignancies. However, its efficacy against solid tumors remains inadequate and is accompanied by toxic side effects, including cytokine release syndrome, neurotoxicity and on-target/off-tumor effects. In contrast to T cells, natural killer (NK) cells exhibit a broader source range and can non-specifically lyse tumor cells. Moreover, it can also reduce toxicity and side effects to some extent. This review comprehensively examines recent research progress on CAR-NK therapy for solid tumors, encompassing both in vivo and in vitro studies, with a focus on CAR-NK cell design and production methods. Drawing upon laboratory and clinical evidence, this review summarizes the current challenges and side effects associated with CAR-NK technology.