To determine whether AC484 efficacy requires PTPN2/N1 inhibition in tumour cells, we implanted Ptpn2/n1-deficient or control B16 tumours into mice, treated all the mice with a low dose of granulocyte-macrophage colony-stimulating factor (GM-CSF)-secreting, irradiated tumour cell vaccine (GVAX), and compared the effect of AC484 or vehicle treatment. The gene discussed is PTPN2; the disease is neoplasm.