Therefore, as proof of principle, we treated the COPD cells and CS-exposed normal cells with 2-Cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me), a potent Nrf2 activator to assess the effects of the pharmacological increase in E-cadherin. Here, CDH1 is linked to chronic obstructive pulmonary disease.