Comprehensive gene expression profiles reveal pathways related to the pathogenesis of chronic obstructive pulmonary disease

Abstract

To better understand the molecular basis of chronic obstructive pulmonary disease (COPD), we used serial analysis of gene expression (SAGE) and microarray analysis to compare the gene expression patterns of lung tissues from COPD and control smokers. A total of 59,343 tags corresponding to 26,502 transcripts were sequenced in SAGE analyses. A total of 327 genes were differentially expressed (1.5-fold up-or down-regulated). Microarray analysis using the same RNA source detected 261 transcripts that were differentially expressed to a significant degree between GOLD-2 and GOLD-0 smokers. We confirmed the altered expression of a select number of genes by using real-time quantitative RT-PCR. These genes encode for transcription factors (EGR1 and FOS), growth factors or related proteins (CTGF, CYR61, CX3CL1, TGFB1, and PDGFRA), and extracellular matrix protein (COL1A1). Immunofluorescence studies on the same lung specimens localized the expression of Egr-1, CTGF, and Cyr61 to alveolar epithelial cells, airway epithelial cells, and stromal and inflammatory cells of GOLD-2 smokers. Cigarette smoke extract induced Egr-1 protein expression and increased Egr-1 DNA-binding activity in human lung fibroblast cells. Cytomix (tumor necrosis factor ␣, IL-1␤, and IFN-␥) treatment showed that the activity of matrix metalloproteinase-2 (MMP-2) was increased in lung fibroblasts from EGR1 control (؉/؉) mice but not detected in that of EGR1 null (؊/؊) mice, whereas MMP-9 was regulated by EGR1 in a reverse manner. Our study represents the first comprehensive analysis of gene expression on GOLD-2 versus GOLD-0 smokers and reveals previously unreported candidate genes that may serve as potential molecular targets in COPD.

GGPPS, a New EGR-1 Target Gene, Reactivates ERK 1/2 Signaling through Increasing Ras Prenylation

“…[17][18][19] We found that EGR-1 activation normally precedes GGPPS expression when Beas-2B cells were stimulated with CSE. The accumulation of EGR-1 protein quickly increased within 30 minutes, and the protein level of GGPPS increased 1 to 6 hours after continuous CSE treatment (Figure 2A, upper panel).…”

“…19 For Western blotting, equal amounts of protein for each group were resolved on 10% SDS-PAGE and then transferred onto polyvinylidene difluoride membranes (Bio-Rad, Hercules, CA). The membranes were then incubated with the appropriate primary antibody as indicated.…”

“…2 We have previously reported that human primary lung fibroblasts can synthesize matrix metalloproteinase (MMP) and chemokines in an EGR-1-dependent manner when exposed to cigarette smoke extract (CSE) stress. [17][18][19] To further understand the pathological functions of EGR-1 in pulmonary diseases during cigarette smoke-induced stress, we screened new target genes using chromatin immunoprecipitation (ChIP) methods. We have found that geranylgeranyl diphosphate synthase (GGPPS) is one of the novel EGR-1 target genes that mediate the function of EGR-1 during cigarette smoke exposure.…”

The EP4 receptor antagonist, L-161,982, blocks prostaglandin E2-induced signal transduction and cell proliferation in HCA-7 colon cancer cells

“…PCR primers used to amplify egr-1 were: F-5'-AGCAGCACCTTCAACCCTCA-3'; R-5'-CAGCACCTTCTCGTTGTTCAGA-3'. The egr-1 primers were originally designed by Ning et al [22]. Differences in egr-1 mRNA levels between the vehicle and PGE 2 -treated samples were determined using the threshold cycle (C T ) method [23].…”

Smoking and FOS expression from blood leukocyte transcripts in patients with coronary artery disease

“…However, there are very few data on the impact of smoking on this key oncogene. Comprehensive gene expression profiles reveal that c-Fos is specifically expressed in the lung tissue of smokers [10]. In adult rat aortic VSMC and adventitial fibroblasts, exposure to nicotine, a major 0021-9150/$ -see front matter © 2011 Elsevier Ireland Ltd. All rights reserved.…”