Another recent study in metastatic urothelial carcinoma showed that lack of response to checkpoint inhibitor therapy was associated with increased TGFβ signaling in fibroblasts in the tumor microenvironment.42 These observations further corroborate that the fibrosis/EMT/ECM biological signals represented by CTL-Ex signature may be generalizable across different tumor types (Fig. 2e). The gene discussed is TGFB1; the disease is neoplasm.