Mechanistically, IR induced cytoplasmic dsDNA and activated cGAS-STING pathway in tumor cells that could release immunoactive cytokines and chemokines including IFN-β, CXCL10, and CCL5 to trigger bystander/abscopal T cells to release IFN-γ and inhibit tumor growth, especially under the situation of PD-L1 deficiency. This evidence concerns the gene CGAS and neoplasm.