CACNA2D2 and chronic obstructive pulmonary disease: Among the top 10 interaction pQTMs, eight were annotated to protein-coding genes, and all of those have previously been associated with either COPD or smoking (PRKAG2, ACSF3, IL6ST, CREBBP, KIF1A, SLURP1, CACNA2D2, and INSC), indicating biologically plausible results, and also a potential role for these genes in the dysregulation of MMP-12 in COPD.