In a pulmonary fibrosis model, Kurundkar et al. showed that CCN1 was upregulated in the lung tissue of patients with idiopathic pulmonary fibrosis and it activated the TGF‐β1/Smad3 signalling pathway, CCN1 was expressed in response to the increase in the expression of profibrotic genes induced by the lung injury, resulting in pulmonary fibrosis.34, 35. Here, SMAD3 is linked to idiopathic pulmonary fibrosis.