CGAS and neoplasm: However, radiotherapy exerts dualistic immunomodulatory effects: while it activates cGAS-STING signaling through radiation-induced DNA damage and ROS generation, thereby promoting type I IFN–mediated antitumor immunity (3, 37), it concurrently recruits and activates immunosuppressive populations including Tregs, tumor-associated neutrophils (TANs), tumor-associated macrophages (TAMs), and MDSCs in the TME (38–41).