TGFB1 and cancer: TGF-β induces matrix production and alters integrin expression and thus promotes tumor growth by stabilizing angiogenesis 112, and activated TGF-β also upregulates urokinase (plasminogen activator), urokinase receptor, and plasminogen activator inhibitor-1 (PAI-1) in the proteolytic system and enhances the invasiveness of malignant tumors 113.