EGFR and chronic obstructive pulmonary disease: Lim et al. (33), for instance, reported that COPDwas significantly correlated with EGFR mutationsin non-smoker non-small-cell lung cancer patients.Importantly, the present study shows that EGFR wasdifferentially expressed in COPD and was also presentin the ‘non-small cell lung cancer’ enriched pathway.Taken together, the pathways associated with lungcancer suggest that COPD is a likely factor of lungcancer development.