Studies have demonstrated that the ALK‐5 inhibitor compound SB‐525334, which targets TGF‐β signaling, prevented both the induction and progression of pulmonary fibrosis, when administered either prophylactically (Higashiyama et al. 2007) or therapeutically (Peng et al. 2013) to bleomycin‐challenged mice. This evidence concerns the gene TGFBR1 and pulmonary fibrosis.