BBR inhibits TGF- β1-induced EMT development. (A) Control A549 cells treated with DMSO display classical epithelial morphology (control group); A549 cells show a pebble-like shape and tight cell-cell adhesion. (B) Morphological changes of A549 cells induced by 5 ng/mL of TGF-β1 for 48 h; TGF-β1-treated cells show a decrease in cell-cell contacts and adopt a more elongated morphological shape representing a mesenchymal phenotype (TGF-β group). (C) A549 cells treated with 5 ng/mL of TGF-β1 plus 10 μM of BBR for 48 h also show the mesenchymal phenotype (TGF-β + BBR 10 group). (D) A549 cells treated with 5 ng/mL of TGF-β1 plus 20 μM of BBR for 48 h display epithelial morphology (TGF-β + BBR 20 group) (Magnification × 200).