Compared to their control counterparts, people with COPD had elevated levels of NGAL, heparin-binding EGF-like growth factor (HB-EGF), extracellular newly identified RAGE-binding protein (EN-RAGE; also known as S100A12), MPO, fibrinogen and transforming growth factor alpha (TGF-α). Here, HBEGF is linked to chronic obstructive pulmonary disease.