CP4715 inhibited proliferation of IPF lung fibroblasts after 24 h (14.6 ± 8.9%, P < 0.05), after 48 h (19.3 ± 10.1%, P < 0.05), and after 72 h (29.1 ± 12.3%, P < 0.05) at the same levels as periostin silencing (Fig. 6a). This evidence concerns the gene POSTN and idiopathic pulmonary fibrosis.