Notably, TGF-β plays a central role in the recruitment of fibroblasts to tumours and their conversion to cancer-associated fibroblasts, while increased TGF-β expression correlates with the accumulation of fibrotic desmoplastic stroma (69) and is strongly associated with T cell exclusion in human tumours (17, 70, 71). The gene discussed is TGFB1; the disease is cancer.