Signal transducer and activator of transcription (STAT)-3, another TGF-β1-dependent stimulator of fibroblast activation, as well as HSP-47, a collagen-specific heat shock protein and an indicator of pulmonary fibrosis, were also decreased by emodin, further showing its antifibrotic activity (Guan et al., 2016). This evidence concerns the gene STAT3 and pulmonary fibrosis.