IL17A and chronic obstructive pulmonary disease: Preclinical studies show that IL-17A mediates cytokine and chemokine expression in structural epithelial cells, affecting neutrophilia, remodeling of the airway, loss of lung function and lung damage in COPD, cystic fibrosis, and asthma, as well as tumor proliferation and immunotherapy-resistance [33], cell invasion, metastasis, and angiogenesis [32].