SMAD3 and lung cancer: (B) Enhancer action: Zhang and colleagues showed that M2-like tumor-associated macrophages (TAM2) infiltration facilitates a rich TGFβ microenvironment and promotes SMAD3 binding to the enhancer of Linc01977, therefore initiating malignancy through the TGFβ/SMAD3 pathway in lung cancer (Fig. 1B) [14].