TGFB1 and lung cancer: Then, we found that the TGF-β1, TGF-β2, and TGF-β3 levels in the supernatants of A549 human lung cancer cells and SW480 human colon cancer cells decreased after UDCA treatment; in addition, the differentiation of human Treg cells induced by the supernatants of both UDCA-treated cells was reduced, and this effect was abolished by TGF-β1-neutralizing antibodies (anti-TGF-β1) (Fig. 6b, c).