NFKB1 and chronic obstructive pulmonary disease: Oxidative stress is the primary cause of COPD pathogenesis, triggering apoptosis, extracellular matrix remodeling, inactivation of protease inhibitors, mucus secretion, NF-κB activation, mitogen-activated protein kinase (MAPK) activation, chromatin remodeling, and pro-inflammatory gene transcription [71,74,75].