SOX4 and idiopathic pulmonary fibrosis: SOX4 acts as a transcription factor and is associated with lung development and cell survival, whereas DKK1 is an inhibitor of the Wnt signaling pathway that have a significant role in lung development and differentiation and IPF pathogenesis and progression (Menezes et al., 2012; Guan and Zhou, 2017; Pan et al., 2017).