Addition of TGF-β1 (10 ng/ml) did not change the decorin production (Figure 4C and 4D), whereas TGF-β1 enhanced the production of biglycan 6.6-fold in fibroblasts from control subjects (p < 0.01; Figure 5C) and 3.0-fold in fibroblasts from COPD patients (p < 0.05; Figure 5D) and the biglycan production after TGF-β1 stimulation was significantly higher in fibroblasts from control subjects compared to fibroblast from COPD patients (p < 0.05). Here, DCN is linked to chronic obstructive pulmonary disease.