As shown in Fig. 5D, synergistic induction of CXCL9/CXCL10 was completely ablated by IFNGR1 depletion, and partly inhibited by IFNAR1 depletion, indicating that Ewing sarcoma–intrinsic signaling through both pathways contributes to this feedforward loop. Here, CXCL10 is linked to Ewing sarcoma.