Of note, despite the rationale behind ‘trapping’ TGF-β for cancer therapy,1035 the unsatisfied clinical results of M7824 (also known as Bintrafusp alfa) in NSCLC and biliary tract cancers (BTCs)1036 raise the concern of TGF-β-targeting strategy, and further research is required to fully understand the biology of TGF-β in TME. Here, TGFB1 is linked to biliary tract neoplasm.