In the study by Kranenburg and coworkers [33], COPD airways were associated with an increased expression of VEGF in several cell populations, such as in the bronchial, bronchiolar, and alveolar epithelium and in bronchiolar macrophages, as well as airway smooth muscle and vascular smooth muscle cells in both the bronchiolar and alveolar regions. This evidence concerns the gene VEGFA and chronic obstructive pulmonary disease.