It is decreased in IPF lungs, it is inhibited by TGFB1 through direct effect of SMAD3, and when it is inhibited, it ceases to inhibit HMGA2, allowing amplification of TGFB1 signaling and early fibrotic changes in vivo and in vitro (98). This evidence concerns the gene TGFB1 and idiopathic pulmonary fibrosis.