Cancer immunotherapy: Classification, therapeutic mechanisms, and nanomaterial-based synergistic therapy

Cancer immunotherapy has emerged as a burgeoning field to fight cancer by stimulating the innate or adaptive immune system of the patient. Nowadays, cancer vaccines, immune checkpoint inhibitors, remodeling tumor microenvironment (TME), oncolytic virotherapy, immunogenic cell death (ICD) therapy, adoptive cell therapy (ACT), and chimeric antigen receptor (CAR)-T cells as effective ways against cancer, the mechanism has been intensively studied. However, a low response rate and immune-related adverse effects (irAEs) remain challenging issues during its management. Nanomaterials hold great promise in augmenting the efficiency of cancer immunotherapy. Importantly, an integrated nanoplatform combining conventional treatments with cancer immunotherapy has superior efficacy for tumor eradication via precision targeting. In this review, the connotation and approach of cancer immunotherapy are first comprehensively summarized. And recent advances in nanomaterials for cancer immunotherapy are then highlighted, emphasizing the synergistic effect of nanomaterial-based treatment platforms combined with cancer immunotherapy. Finally, current problems in cancer treatment and future perspectives to develop the most applicable nanomedicines for cancer immunotherapy are thoroughly discussed.