FLT1 and chronic obstructive pulmonary disease: In the present study, we explored the role of VEGF, VEGFR1, VEGFR2 in the small-airway remodelling associated with lipopolysaccharide (LPS) injection and cigarette smoke (CS) inhalation induced COPD and prioritized investigation of the curative effect of sunitinib, a typical tyrosine kinase inhibitor, in the treatment of COPD.