The levels of seven proteases, specifically ADAM8 (p = 0.0327), ADAM9 (p = 0.0094), Cathepsin E (p = 0.0282), MMP8 (p = 0.0179), Neprilysin/CD10 (p = 0.0243), Protein convertase 9 (p = 0.0282), and uPA/Urokinase (p = 0.0433) were lower in AD patients compared to healthy controls. The gene discussed is PLAU; the disease is Alzheimer disease.