Extending beyond target identification, the role of HIF-1a signaling was further explored with a series of experiments which revealed overexpression in the hyperplastic epithelium of IPF patients, colocalizing with its target genes, p53 and vascular endothelial growth factor (VEGF), involved in apoptosis and angiogenesis, respectively[15]. This evidence concerns the gene VEGFA and idiopathic pulmonary fibrosis.