BAG3 and familial dilated cardiomyopathy: However, consistent alterations in the expression of profibrotic genes (tissue inhibitor of metalloproteinases 3, TGF-β2, platelet-derived growth factor subunits A and D) were evident in all fibroblasts affected by DCM, including those in BAG3 hearts (Supplemental Figure 6, G and I) (28, 57, 58).