Most recently, Cullin4A (CUL4A), an E3 ubiquitin ligase associated with EMT in non-small cell lung cancer, is also overexpressed in the lung epithelium of COPD patients and could be associated with the poor differentiation and function of the small airway epithelium (Ren et al., 2019) There still remains some controversy over the specific role for an active EMT transition in the pathogenesis of COPD. The gene discussed is CUL4A; the disease is chronic obstructive pulmonary disease.