Since human lung fibroblasts produce increased amounts of VEGF in the presence of several mediators, including TGF-ß1 and PGE2, which are highly associated with pathogenesis of COPD [8, 25], we determined if the effect of miR-503 would be observed in the presence of each of these stimuli. The gene discussed is VEGFA; the disease is chronic obstructive pulmonary disease.