By producing Fibroblast Activation Protein-alpha (FAP) gene-engineered tumor-cell-derived exosome-like nanovesicles (eNVs–FAP) as a tumor vaccine, the authors were able to inhibit tumor growth, induce cytotoxic T lymphocyte (CTL) immunity against colon, melanoma, lung and breast cancer models, and reprogram the TME. The gene discussed is FAP; the disease is neoplasm.