COPD susceptibility gene HHIP regulates repair genes in airway epithelial cells and repair within the epithelial-mesenchymal trophic unit

We show that overexpression of HHIP protected from cigarette smoke-induced epithelial-to-mesenchymal transition and promoted epithelial regeneration via epithelial-mesenchymal cross talk in non-COPD controls. Thus, the lower expression of HHIP in airway epithelial cells from patients with COPD may contribute to abnormal epithelial repair in both proximal and distal parts of the lungs of patients with COPD.