S100A4 and systemic sclerosis: In SSc fibrocytes, nintedanib 0.1 μM and 1 μM downregulated the gene expression of αSMA, S100A4, COL1, and FN after 3 h of treatment compared to untreated cells (p < 0.05 and p < 0.01 for αSMA; p < 0.05 for S100A4; p < 0.05 and p < 0.01 for COL1; p < 0.01 for FN) (Fig. 3A).