Studies using either bronchial-epithelial cells [27] or A549 lung cancer cells [15] to investigate the effect of TGFβ, suggested that EMT in these cells is SMAD-dependent and further studies employing AECII from mice could show that these cells undergo EMT in response to bleomycin in vivo [28] or in vitro [29], assuming a relevance during IPF pathogenesis. This evidence concerns the gene TGFB1 and idiopathic pulmonary fibrosis.