TGFB1 and neoplasm: identified TGFβ signaling in fibroblasts as a critical factor contributing to the lack of response to ICIs in metastatic urothelial cancer, particularly in tumors where CD8+ T cells are excluded and localized to the peritumoral stroma.[203] Moreover, co‐administration of TGFβ‐blocking and anti‐PD‐L1 antibodies reduces TGFβ signaling, enhances T cell infiltration, and triggers tumor regression.[204] These findings position CAFs as promising therapeutic targets within the TME.