Research status of colorectal cancer treatment based on natural killer cell immunotherapy

Abstract Colorectal cancer (CRC) is a digestive tract malignancy with the highest global incidence and mortality rate. In China, the number of patients with colorectal cancer has been increasing annually. In 2020, the numbers of new cases and cancer deaths were 560,000 and 290,000, respectively, ranking second among new cancer cases and fifth among cancer deaths in China. Treatment of colorectal cancer involves a combined regimen of surgery supplemented with radiotherapy, chemotherapy, targeted therapy, and immunotherapy. This article comprehensively analyzed the classification and function of natural killer (NK) cells, their development and metabolic processes, expression and effector mechanisms, their effects on colorectal cancer, and the development prospects of using NK cells to treat colorectal cancer. Here, we comprehensively review preclinical and clinical investigations exploring the therapeutic effects and mechanisms of NK cell–based immunotherapy against CRC. This approach not only leverages NK cells’ unique abilities to recognize and eliminate tumor cells but also overcomes the immunosuppressive tumor microenvironment in advanced CRC, providing a promising strategy for future therapeutic development.