Chimeric Antigen Receptor Cell Therapy: Empowering Treatment Strategies for Solid Tumors

Chimeric antigen receptor-T (CAR-T) cell therapy has demonstrated impressive efficacy in the treatment of blood cancers; however, its effectiveness against solid tumors has been significantly limited. The differences arise from a range of difficulties linked to solid tumors, including an unfriendly tumor microenvironment, variability within the tumors, and barriers to CAR-T cell infiltration and longevity at the tumor location. Research shows that the reasons for the decreased effectiveness of CAR-T cells in treating solid tumors are not well understood, highlighting the ongoing need for strategies to address these challenges. Current strategies frequently incorporate combinatorial therapies designed to boost CAR-T cell functionality and enhance their capacity to effectively target solid tumors. However, these strategies remain in the testing phase and necessitate additional validation to assess their potential benefits. CAR-NK (natural killer), CAR-iNKT (invariant natural killer T), and CAR-M (macrophage) cell therapies are emerging as promising strategies for the treatment of solid tumors. Recent studies highlight the construction and optimization of CAR-NK cells, emphasizing their potential to overcome the unique challenges posed by the solid tumor microenvironment, such as hypoxia and metabolic barriers. This review focuses on CAR cell therapy in the treatment of solid tumors.