MMP-1, MMP-8, MMP-9 and MMP-12 have been shown to be upregulated in the disease region of chronic obstructed pulmonary disease (COPD), which is a chronic inflammatory airway disorder commonly caused by cigarette smoking and occupational inhalation (e.g., dust or chemicals) [139]. The gene discussed is MMP8; the disease is chronic obstructive pulmonary disease.