CDKN2A and chronic obstructive pulmonary disease: Briefly, in the lungs of patients with COPD, there is an accumulation of senescent cells including alveolar epithelial cells, endothelial cells, pulmonary artery smooth muscle cells as well as fibroblasts overexpressing markers of senescence such as p16 (also known as p16INK4a, cyclin‐dependent kinase inhibitor 2A, CDKN2A), p21 (cyclin‐dependent kinase inhibitor 1) and senescence‐associated beta‐galactosidase (SA‐β‐gal) (Amsellem et al., 2011; Noureddine et al., 2011; Tsuji et al., 2006; Woldhuis et al., 2021).