Stimuli with TGF-β induced higher release of IL-8 (p = 0.023, Fig. 4b) and PGE2 (p = 0.036,  Fig. 4f) in lung fibroblasts from COPD patients compared to control subjects at normoxia (Fig. 4). This evidence concerns the gene CXCL8 and chronic obstructive pulmonary disease.