Under conditions of hypoxia, PAI‐1 expression is upregulated in pulmonary macrophages, arterial smooth muscle cells (PASMC) and endothelial cells (Diebold et al. 2011), thereby providing a possible link between interstitial pulmonary fibrosis, alveolar hypoxia, and vascular remodeling. This evidence concerns the gene SERPINE1 and pulmonary fibrosis.