Because the consequence of LXRa deregulation resulting in exacerbated lung fibrosis became apparent in miR-155−/− mice only when stressed with bleomycin, we compared the dynamic interaction between miR-155 and LXRα in control and IPF fibroblasts cultured under the hypoxic stress (1% O2) that mimics the lung environment in IPF.31 The gene discussed is NR1H3; the disease is idiopathic pulmonary fibrosis.