A nasal gene expression profile differentiates individuals with and without COPD and overlaps bronchial gene expression

Introduction: Nasal gene expression profiling is a promising method to characterize COPD non-invasively. First, we aimed to identify a nasal gene expression profile that distinguishes COPD patients from healthy controls. Next, we investigated whether this COPD-associated gene expression profile in nasal epithelium is comparable with the profile in the lower airways, i.e. the bronchial epithelium. Methods: Genome wide gene expression analysis was performed on nasal epithelial brushes of 76 COPD patients and 39 healthy controls, using Affymetrix Human Gene 1.0 ST Arrays. To compare findings in nasal and bronchial epithelium, we repeated the gene expression analysis on bronchial epithelial brushes in 2 independent cohorts of COPD patients and controls. Results: We found 2673 genes to be significantly differentially expressed in nasal epithelium between COPD patients and controls, 1158 being up- and 1515 downregulated in COPD (false discovery rate Conclusion: We identified a nasal gene expression profile that differentiates individuals with and without COPD. Of interest, part of the nasal gene expression changes in COPD is comparable to differentially expressed genes in the bronchus. These findings indicate that nasal gene expression has the potential to be developed as a non-invasive biomarker in COPD.