HDAC2 and chronic obstructive pulmonary disease: A decreased HDAC2 activity has been associated with inflammation and senescence in COPD patients via the increase of histones H3 and H4 acetylation, the activation of the transcription factor, nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NF-κB), and the unscheduled transcription of proinflammatory genes [66,71,72].