Factors Influencing Immunotherapy Response in Neuroblastoma: From Tumor Microenvironment to Combination Strategies

Neuroblastoma is the most common extracranial solid tumor in children, and the prognosis for high-risk patients remains dismal. Immunotherapies, represented by anti-GD2 monoclonal antibodies and chimeric antigen receptor T cells (CAR-T), have significantly improved the survival of high-risk neuroblastoma patients and become part of standard therapy. However, their efficacy exhibits significant inter-individual heterogeneity, with some patients showing primary resistance or secondary relapse. This review aims to analyze the multi-faceted factors influencing the response to immunotherapy in neuroblastoma, including: (1) the inherent immunosuppressive properties of the tumor microenvironment, such as infiltration of myeloid-derived suppressor cells and tumor-associated macrophages, as well as checkpoint molecules and metabolic barriers; (2) tumor cell-intrinsic characteristics, such as low tumor mutational burden, MYCN amplification-associated downregulation of MHC-I, and heterogeneity of GD2 antigen expression; (3) host factors, such as systemic immune status and Fc receptor polymorphisms; and (4) treatment-related factors, such as combination strategies and the development of novel immunotherapeutic products. A deep understanding of these interrelated factors is crucial for developing predictive biomarkers, designing novel combination strategies and next-generation immunotherapies, and ultimately achieving precise immunotherapy for neuroblastoma.