Chronic obstructive pulmonary disease (COPD) is a major cause of mortality worldwide, and there is currently no treatment that can halt the progression of the disease. Over the last decade there has been increasing interest in the idea that epithelial-mesenchymal transition (EMT) may be active in COPD. Here we review the evidence for EMT in COPD as well as the current progress being made on understanding the drivers and mechanisms involved. Finally, we discuss the potential benefits that understanding EMT may bring to the field of chronic respiratory disease.

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