CD8A and neoplasm: Both in vitro and in vivo studies demonstrate that TSF@ES‐Cu NPs induce cuproptosis, triggering immunogenic cell death (ICD), promoting dendritic cell maturation, facilitating CD8+ T cell infiltration, and reducing M2 cells in tumor, which enhances anti‐tumor immune responses, overcomes tumor immunosuppression and remodels the tumor immune microenvironment.