Galunisertib, as a TGF-β inhibitor (Figure 1A), significantly reduced the protein and mRNA levels of TGF-β in silica-induced silicosis mice, and Western blot analysis showed that high-dose Galunisertib also significantly inhibited the expression of Col-I and α-SMA proteins, two important markers of fibrosis (Figures 1F–I). Here, ACTA1 is linked to silicosis.