Project description:The apical junctional complex (AJC), composed of tight junctions and adherens junctions, is essential for maintaining epithelial barrier function. Since cigarette smoking and chronic obstructive pulmonary disease (COPD), the major smoking-induced disease, are both associated with increased lung epithelial permeability, we hypothesized that smoking alters the transcriptional program regulating AJC integrity in the small airway epithelium (SAE), the primary site of pathological changes in COPD. Transcriptome analysis revealed a global down-regulation of physiological AJC gene expression in the SAE of healthy smokers (n=53) compared to healthy nonsmokers (n=59), an observation associated with changes in molecular pathways regulating epithelial differentiation such as PTEN signaling and accompanied by induction of cancer-related AJC genes. Genome-wide co-expression analysis identified a smoking-sensitive AJC transcriptional network. The overall expression of AJC-associated genes was further decreased in COPD smokers (n=23). Exposure of human airway epithelial cells to cigarette smoke extract in vitro resulted in down-regulation of several AJC-related genes, accompanied by decreased transepithelial resistance. Thus, cigarette smoking alters the AJC gene expression architecture in the human airway epithelium, providing a molecular basis for the dysregulation of airway epithelial barrier function during the development of smoking-induced lung disease. The apical junctional complex (AJC), composed of tight junctions and adherens junctions, is essential for maintaining epithelial barrier function. Since cigarette smoking and chronic obstructive pulmonary disease (COPD), the major smoking-induced disease, are both associated with increased lung epithelial permeability, we hypothesized that smoking alters the transcriptional program regulating AJC integrity in the small airway epithelium (SAE), the primary site of pathological changes in COPD. In this study, microarray analysis of the SAE obtained from 53 healthy nonsmokers, 59 healthy smokers, and 23 smokers with COPD was performed to determine physiological AJC gene expression architecture in the SAE and its modification by cigarette smoking and during the development of COPD.
Project description:Rationale: Even after quitting smoking, the risk of the development of chronic obstructive pulmonary disease (COPD) and lung cancer remains significantly higher compared to never-smokers. Objectives: Based on the knowledge that COPD and most lung cancers start in the small airway epithelium (SAE), we hypothesized that smoking modulates miRNA expression in the SAE linked to the pathogenesis of smoking-induced airway disease, and that some of these changes persist after smoking cessation. Methods: SAE was collected from 10th to 12th order bronchi using fiberoptic bronchoscopy. Affymetrix miRNA 2.0 arrays were used to assess miRNA expression in the SAE from 10 healthy never-smokers and 10 healthy smokers, before and after they quit for 3 months. Smoking status was determined by urine nicotine and cotinine measurement. Results: There were significant differences in the expression of 34 miRNAs between healthy smokers and healthy never-smokers (p<0.01, fold-change >1.5), with functions associated with lung development, airway epithelium differentiation, inflammation and cancer. After quitting smoking for 3 months, 12 out of the 34 miRNAs did not return to normal levels, with Wnt/β-catenin signaling pathway the top enriched pathway of the target genes of the persistent deregulated miRNAs. Conclusions: In the context that many of these persistent smoking-dependent miRNAs are associated with differentiation, inflammation diseases or lung cancer, it is likely that persistent smoking-related changes in small airway epithelium miRNAs play a role in the subsequent development of these disorders. MicroRNA profiling identified 34 miRNAs up-regulated by cigarette smoking in human small airway epithelium. Even after quitting smoking for 3 months, 12 miRNAs didnât return to normal level.
Project description:CXCL14, a recently described chemokine constitutively expressed in various epithelia, has multiple putative roles in inflammation and carcinogenesis. Based on the knowledge that cigarette smoking and the smoking-induced disorders, such as chronic obstructive pulmonary disease (COPD) and lung cancer, are associated with inflammation, we hypothesized that the airway epithelium, the primary site of smoking-induced pathologic changes in COPD and adenocarcinoma, responds to cigarette smoking with an altered CXCL14 gene expression as a part of disease-relevant molecular phenotype. Microarray analysis with subsequent TaqMan PCR validation revealed very low constitutive CXCL14 gene expression in the airway epithelium of healthy nonsmokers (n=53) which was strongly up-regulated in healthy smokers ( n=59; p<0.001) and further increased in COPD smokers (n=23; p<10-7 vs nonsmokers; p<0.005 vs healthy smokers). In smokers, CXCL14 expression inversely correlated with lung function parameters FEV1 and FEV1/FVC. Genome-wide analysis also showed that up-regulated correlation of CXCL14 expression with genes related to cell growth and proliferation, squamous differentiation and cancer. The analysis of 193 lung adenocarcinoma samples demonstrated a dramatic up-regulation of CXCL14 in a smoking-dependent manner. [need to include survival data once we get it]. Together, these data suggest that smoking-induced expression of CXCL14 in association with genome-wide reprogramming of processes related to tissue homeostasis, differentiation and tumorigenesis, represents a novel molecular link between cigarette smoking, COPD and lung cancer.
Project description:The apical junctional complex (AJC), composed of tight junctions and adherens junctions, is essential for maintaining epithelial barrier function. Since cigarette smoking and chronic obstructive pulmonary disease (COPD), the major smoking-induced disease, are both associated with increased lung epithelial permeability, we hypothesized that smoking alters the transcriptional program regulating AJC integrity in the small airway epithelium (SAE), the primary site of pathological changes in COPD. Transcriptome analysis revealed a global down-regulation of physiological AJC gene expression in the SAE of healthy smokers (n=53) compared to healthy nonsmokers (n=59), an observation associated with changes in molecular pathways regulating epithelial differentiation such as PTEN signaling and accompanied by induction of cancer-related AJC genes. Genome-wide co-expression analysis identified a smoking-sensitive AJC transcriptional network. The overall expression of AJC-associated genes was further decreased in COPD smokers (n=23). Exposure of human airway epithelial cells to cigarette smoke extract in vitro resulted in down-regulation of several AJC-related genes, accompanied by decreased transepithelial resistance. Thus, cigarette smoking alters the AJC gene expression architecture in the human airway epithelium, providing a molecular basis for the dysregulation of airway epithelial barrier function during the development of smoking-induced lung disease.
Project description:Rationale: Even after quitting smoking, the risk of the development of chronic obstructive pulmonary disease (COPD) and lung cancer remains significantly higher compared to never-smokers. Objectives: Based on the knowledge that COPD and most lung cancers start in the small airway epithelium (SAE), we hypothesized that smoking modulates miRNA expression in the SAE linked to the pathogenesis of smoking-induced airway disease, and that some of these changes persist after smoking cessation. Methods: SAE was collected from 10th to 12th order bronchi using fiberoptic bronchoscopy. Affymetrix miRNA 2.0 arrays were used to assess miRNA expression in the SAE from 10 healthy never-smokers and 10 healthy smokers, before and after they quit for 3 months. Smoking status was determined by urine nicotine and cotinine measurement. Results: There were significant differences in the expression of 34 miRNAs between healthy smokers and healthy never-smokers (p<0.01, fold-change >1.5), with functions associated with lung development, airway epithelium differentiation, inflammation and cancer. After quitting smoking for 3 months, 12 out of the 34 miRNAs did not return to normal levels, with Wnt/β-catenin signaling pathway the top enriched pathway of the target genes of the persistent deregulated miRNAs. Conclusions: In the context that many of these persistent smoking-dependent miRNAs are associated with differentiation, inflammation diseases or lung cancer, it is likely that persistent smoking-related changes in small airway epithelium miRNAs play a role in the subsequent development of these disorders.
Project description:Down-regulation of the Notch Differentiation Pathway in the Human Airway Epithelium in Normal Smokers and Smokers with Chronic Obstructive Lung Disease; In cigarette smokers, the toxic components of smoke place the epithelium under the constant stress of a variety of mechanisms of injury, with consequent modulation of airway epithelial regeneration and disordered differentiation. Based on the underlying hypothesis that these airway epithelial changes must involve quantitative changes in genes involved with the regulation of differentiation, we assessed the expression of the Notch pathway, a signaling pathway known to play a fundamental role in the embryonic lung as a gatekeeper for differentiation, in the small airway epithelium of non-smokers, normal smokers, and smokers with COPD. Microarray analysis demonstrated that 45 of the 55 Notch pathway-related genes are expressed in the human adult small airway epithelium and TaqMan quantitative PCR confirmed the expression of key genes in the pathway. TaqMan quantitative PCR analysis of the normal small airway epithelium demonstrated that Delta-like ligand 1 is the most highly expressed Notch ligand, Notch2 and 3 the most highly expressed receptor genes, and Hes1 the predominant downstream effector gene. TaqMan PCR was used to compare gene expression in nonsmokers vs healthy smokers vs smokers with COPD. The data show that some key genes in the ligands, receptors and downstream effectors in the Notch pathway are differentially expressed in smokers, with significant downregulation of a greater number of Notch-related genes in smokers with COPD compared to healthy smokers. These observations are consistent with the hypothesis that the Notch pathway, known to play an important role in lung morphogenesis, also likely plays a role in the adult human airway epithelium, with at least some of the Notch pathway gene expression dysregulated in association with smoking and its related disorder, COPD. Experiment Overall Design: Gene expression in airway epithelial cells of normal non-smokers.
Project description:Cystatin A (gene: CSTA), is up-regulated in non-small-cell lung cancer (NSCLC) and dysplastic vs normal human bronchial epithelium. In the context that chronic obstructive pulmonary disease (COPD), a small airway epithelium (SAE) disorder, is independently associated with NSCLC (especially squamous cell carcinoma, SCC), but only occurs in a subset of smokers, we hypothesized that genetic variation, smoking and COPD modulate CSTA gene expression levels in SAE, with further up-regulation in SCC. Gene expression was assessed by microarray in SAE of 178 individuals [healthy nonsmokers (n=60), healthy smokers (n=82), and COPD smokers (n=36)], with corresponding large airway epithelium (LAE) data in a subset (n=52). Blood DNA was genotyped by SNP microarray. Twelve SNPs upstream of the CSTA gene were all significantly associated with CSTA SAE gene expression (p<0.04 to 5 x 10-4). CSTA gene expression levels in SAE were higher in COPD smokers (28.4 ± 2.0) than healthy smokers (19.9 ± 1.4, p<10-3), who in turn had higher levels than nonsmokers (16.1 ± 1.1, p<0.04). CSTA LAE gene expression was also smoking-responsive (p<10-3). Using comparable publicly available NSCLC expression data, CSTA was up-regulated in SCC vs LAE (p<10-2) and down-regulated in adenocarcinoma vs SAE (p<10-7). All phenotypes were associated with significantly different proportional gene expression of CSTA to cathepsins. The data demonstrate that regulation of CSTA expression in human airway epithelium is influenced by genetic variability, smoking, and COPD, and is further up-regulated in SCC, all of which should be taken into account when considering the role of CSTA in NSCLC pathogenesis. CSTA gene expression was assessed in the small airway epithelium obtained by bronchoscopy from 178 individuals, including healthy nonsmokers (n= 60) and healthy smokers (n= 118) and the large airway epithelium from healthy nonsmokers (n=21) and healthy smokers(n=31). *** Processed data not provided for all gene expression records. *** Blood DNA from the majority of these individuals was genotyped and an association analysis of gene expression with genotypes of all 48 SNPs within 100 kb of CSTA was performed in PLINK, and tested for significance following 103 permutations within ancestral clusters. Supplementary file (linked below) reports genotypes of all 48 SNPs within 100 kb of the CSTA gene for the 112 genotyping Samples.
Project description:Cystatin A (gene: CSTA), is up-regulated in non-small-cell lung cancer (NSCLC) and dysplastic vs normal human bronchial epithelium. In the context that chronic obstructive pulmonary disease (COPD), a small airway epithelium (SAE) disorder, is independently associated with NSCLC (especially squamous cell carcinoma, SCC), but only occurs in a subset of smokers, we hypothesized that genetic variation, smoking and COPD modulate CSTA gene expression levels in SAE, with further up-regulation in SCC. Gene expression was assessed by microarray in SAE of 178 individuals [healthy nonsmokers (n=60), healthy smokers (n=82), and COPD smokers (n=36)], with corresponding large airway epithelium (LAE) data in a subset (n=52). Blood DNA was genotyped by SNP microarray. Twelve SNPs upstream of the CSTA gene were all significantly associated with CSTA SAE gene expression (p<0.04 to 5 x 10-4). CSTA gene expression levels in SAE were higher in COPD smokers (28.4 ± 2.0) than healthy smokers (19.9 ± 1.4, p<10-3), who in turn had higher levels than nonsmokers (16.1 ± 1.1, p<0.04). CSTA LAE gene expression was also smoking-responsive (p<10-3). Using comparable publicly available NSCLC expression data, CSTA was up-regulated in SCC vs LAE (p<10-2) and down-regulated in adenocarcinoma vs SAE (p<10-7). All phenotypes were associated with significantly different proportional gene expression of CSTA to cathepsins. The data demonstrate that regulation of CSTA expression in human airway epithelium is influenced by genetic variability, smoking, and COPD, and is further up-regulated in SCC, all of which should be taken into account when considering the role of CSTA in NSCLC pathogenesis.
Project description:Rationale: Genome-wide association studies (GWAS) and candidate gene studies have identified a number of loci linked to susceptibility of chronic obstructive pulmonary disease (COPD), a smoking-related disorder that originates in the airway epithelium. Objectives: Since airway basal cell (BC) stem/progenitor cells exhibit the earliest abnormalities associated with smoking (hyperplasia, squamous metaplasia), we hypothesized that smoker BC have a dysregulated transcriptome linked, in part, to known GWAS/candidate gene loci. Methods: Massive parallel RNA sequencing was used to compare the transcriptome of BC purified from the airway epithelium of healthy nonsmokers (n=10) and smokers (n=7). The chromosomal location of the differentially expressed genes was compared to loci identified by GWAS and candidate gene studies to confer risk for COPD. Measurements and Main Results: Smoker BC have 676 known genes differentially expressed compared to nonsmoker BC, dominated by smoking up-regulation. Strikingly, 166 (25%) of these genes are located on chromosome 19, with 13 localized to 19q13.2 (p<10-4 compared to chance), including TGFB1, LTBP4, EGLN2 and NFKBIB, genes associated with risk for COPD. Conclusions: These observations provide the first direct link of known genetic risks for smoking-related lung disease with the specific population of lung cells that undergoes the earliest changes associated with smoking. The human airway basal cell transcriptome of 7 smokers versus 10 nonsmokers was compared using massive parallel RNA sequencing (Illumina HiSeq 2000).
Project description:Down-regulation of the Notch Differentiation Pathway in the Human Airway Epithelium in Normal Smokers and Smokers with Chronic Obstructive Lung Disease In cigarette smokers, the toxic components of smoke place the epithelium under the constant stress of a variety of mechanisms of injury, with consequent modulation of airway epithelial regeneration and disordered differentiation. Based on the underlying hypothesis that these airway epithelial changes must involve quantitative changes in genes involved with the regulation of differentiation, we assessed the expression of the Notch pathway, a signaling pathway known to play a fundamental role in the embryonic lung as a gatekeeper for differentiation, in the small airway epithelium of non-smokers, normal smokers, and smokers with COPD. Microarray analysis demonstrated that 45 of the 55 Notch pathway-related genes are expressed in the human adult small airway epithelium and TaqMan quantitative PCR confirmed the expression of key genes in the pathway. TaqMan quantitative PCR analysis of the normal small airway epithelium demonstrated that Delta-like ligand 1 is the most highly expressed Notch ligand, Notch2 and 3 the most highly expressed receptor genes, and Hes1 the predominant downstream effector gene. TaqMan PCR was used to compare gene expression in nonsmokers vs healthy smokers vs smokers with COPD. The data show that some key genes in the ligands, receptors and downstream effectors in the Notch pathway are differentially expressed in smokers, with significant downregulation of a greater number of Notch-related genes in smokers with COPD compared to healthy smokers. These observations are consistent with the hypothesis that the Notch pathway, known to play an important role in lung morphogenesis, also likely plays a role in the adult human airway epithelium, with at least some of the Notch pathway gene expression dysregulated in association with smoking and its related disorder, COPD. Keywords: non-smokers, airway epithelial cells