Nanomaterials for Combinational Radio–Immuno Oncotherapy

Abstract Radiotherapy, a clinically used local treatment modality of cancers, is regarded as a promising candidate to promote current immunotherapy through initiating an in situ vaccination effect and reprogramming the immunosuppressive microenvironment. The combination of radiotherapy and immunotherapy, referred to as combinational radio–immuno oncotherapy (CRIOT), elicits a synergistic antitumor effect based on the immunomodulatory properties of radiation. Unfortunately, current CRIOT accompanies low response rate and severe toxicity in clinical trials, thus limiting its application. To this end, various nanomaterials are being developed to sensitize radiotherapy or deliver immune agents, or both, to improve the unsatisfactory outcomes of CRIOT. Herein, enhanced antitumor efficacy of CRIOT with nanomaterials through the possible mechanisms of rejuvenation and activation of T cells, increased presentation of tumor‐related antigens, and inhibition of suppressive macrophages is presented, and the prospect of CRIOT in clinical practice is proposed.