Meanwhile, compared to ordinary nanoparticles, metallic nanoparticles can be used to design on-demand cancer immunotherapy delivery systems based on nanoparticles due to the inherent immunomodulatory effects of metal ions, such as activation of the cGAS–STING pathway, modulation of bacterial flora, polarization of M1-type macrophages, and induction of cellular focal death. The gene discussed is STING1; the disease is cancer.