In a syngeneic mouse model of high-grade serous ovarian carcinoma, ΔVF virus lacking the viral thymidine kinase (TK), armed with granulocyte-macrophage colony-stimulating factor (GM-CSF), and expressing NeonGreen (ΔVFTK-NG-GM-CSF) is tumor-specific. The gene discussed is TKT; the disease is ovarian serous carcinoma.