Following the above series of experiments and to shed further light on the fibrogenic cascade, we sought to determine the expression profiles of ING4, also known as inhibitor of HIF-1a, in different forms of pulmonary fibrosis, including the experimental model and two types of idiopathic fibrotic lung disease, IPF and COP. The gene discussed is ING4; the disease is idiopathic pulmonary fibrosis.