Regional heterogeneity in response of airway epithelial cells to cigarette smoke

To investigate the biochemical and genetic alterations that occur in response to cigarette smoke exposure among airway epithelial cells from different sites in the lungs, we performed microarray-based analysis using small airway epithelial cells (SAEC) and normal human bronchial epithelial cells (NHBE) following 24 h of cigarette smoke extract (CSE). In microarray-based analysis, the small airway showed higher susceptibility to CS compared to the large airway, such as enhanced expression of inflammatory-related pathways including the TNF signaling pathway. Among the TNF-related genes, PTGS2, also known as COX-2, showed the greatest difference in expression levels, with higher CSE-induced increments of both mRNA and protein expression in SAEC compared to NHBE. SAEC and NHBE were subjected to 2.5% CSE for 24h. Microarray-based analysis was used to identify gene and protein expression profiles that are altered by CSE exposure in both cell types.