Hierarchical Microparticles Delivering Oxaliplatin and NLG919 Nanoprodrugs for Local Chemo-immunotherapy

and retained locally to reduce systemic toxicity. After being endocytosed by cancer cells, the cytotoxic oxaliplatin and NLG919 could be successfully triggered to release from DDP NPs in a chain-shattering manner, leading to the immunogenic cell death (ICD) of tumor cells and the suppression of intratumoral immunosuppressive Tregs, respectively. With the assistance of an immune modulator, the chemotherapeutics-induced ICD could trigger robust systemic antitumor immune responses, presenting superior synergistic antitumor efficacies. Thus, the hierarchical microparticles could substantially inhibit the growth of mouse subcutaneous colorectal tumors, breast tumors, and colorectal tumors with large initial sizes via synergized chemo-immunotherapy, showing great potential in the practical clinical application of oncotherapy.