While Zhang, Deng, Wu and colleagues demonstrated that tumor-specific ablation of HO-1 could potentiate RT in vivo through STING (11), the observed antitumor effects in vivo could have been mediated by transfer of extracellular cGAMP produced by cancer cells to trigger STING in DCs within the tumor microenvironment (1). Here, HMOX1 is linked to neoplasm.