In vivo and in vitro experiments demonstrated that GQD-PEG effectively inhibited tumor growth under light exposure, while also activating the host immune response, inducing CD8+ T cell tumor infiltration, and promoting the release of inflammatory cytokines such as IFN-γ and TNF-α, thereby achieving a synergistic effect of PDT and tumor immunotherapy. The gene discussed is IFNG; the disease is neoplasm.