The results confirmed that AD4-GHPE exhibits three antitumor mechanisms, namely, tumor-specific cytotoxicity, a reduction in programmed death ligand 1 (PD-L1) expression in tumor cells to increase CD8+ T-cell activity, and granulocyte–macrophage colony-stimulating factor (GM-CSF) secretion. The gene discussed is PSEN2; the disease is neoplasm.