Methods: Flank tumors formed in BALB/c mice with syngeneic CT26 colon or 4T1 mammary carcinoma cells were treated with otherwise ineffective doses of ionizing radiation (10 Gy) followed by CBI (0.2 mg anti-PD-L1, i.v.)after 0, 1, 3, 5, or 7 days, comparing tumor response. The gene discussed is CD274; the disease is neoplasm.