As compared to nanoparticle-mediated, noncovalent drug encapsulation, stimulusresponsive prodrug nanoparticles have a pharmaceutical advantage: they can be tuned to minimize drug leakage and to control drug release profiles through chemical linkers and have recently been developed as a strategy to enhance the cancer immunotherapy effectiveness. Iron oxide-zinc oxide core-shell NPs have been successfully used to deliver carcinoembryonic antigen into dendritic cells while simultaneously acting as an imaging agent. Gold-silver core-shell hybrid NPs have been reported to attenuate the tumor cell-promoting activity of cancer-associated fibroblasts, leading to a prominent attenuation of metastatic dissemination in vivo. Hybrid NPs comprising of two or more constituents with different compositions and properties, typically organic and inorganic, have been developed, combining the functions of participating materials and exhibiting immense potential in advancing cancer immunotherapy. Upconversion NPs devised for cancer therapy typically have employed photoinitiators and dyes to enhance reactive oxygen species by producing radicals in the tumor site through photodynamic therapy. Use of stimuli-responsive delivery systems can enable spatiotemporal control over drug release.