All test animals were divided into four groups, control, carbon ion-irradiated unilateral hindlimb tumor, PD-L1+CTLA-4 inhibitor alone (PD-L1+CTLA 4 group), and carbon ion-irradiated unilateral hindlimb tumor coupled with PD-L1+CTLA 4 group (Comb group). The gene discussed is CTLA4; the disease is neoplasm.