The small airway epithelium (SAE), the first site of smoking-induced lung pathology, exhibits genome-wide changes in gene expression in response to cigarette smoking. Based on the increasing evidence that the epigenome can respond to external stimuli in a rapid manner, we assessed the SAE of smokers for genome-wide DNA methylation changes compared to nonsmokers, and whether changes in SAE DNA methylation were linked to the transcriptional output of these cells. Using genome-wide methylation analysis of SAE DNA of nonsmokers and smokers, the data identified 204 unique genes differentially methylated in SAE DNA of smokers compared to nonsmokers, with 67% of the regions with differential methylation occurring within 2 kb of the transcriptional start site. Among the genes with differential methylation were those related to metabolism, transcription, signal transduction and transport. For the differentially methylated genes, 34 exhibited a correlation with gene expression, 53% with an inverse correlation of DNA methylation with gene expression and 47% a direct correlation. These observations provide evidence that cigarette smoking alters the DNA methylation patterning of the SAE and that, for some genes, these changes are associated with the smoking-related changes in gene expression.
Cigarette smoking induces small airway epithelial epigenetic changes with corresponding modulation of gene expression.
Specimen part
View SamplesRationale: 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. Overall design: The human airway basal cell transcriptome of 7 smokers versus 10 nonsmokers was compared using massive parallel RNA sequencing (Illumina HiSeq 2000).
Smoking dysregulates the human airway basal cell transcriptome at COPD risk locus 19q13.2.
Specimen part, Subject
View SamplesAging involves multiple biologically complex processes characterized by a decline in cellular homeostasis over time leading to a loss and impairment of physiological integrity and function. Specific cellular hallmarks of aging include abnormal gene expression patterns, shortened telomeres and associated biological dysfunction. Like all organs, the lung demonstrates both physiological and structural changes with age that result in a progressive decrease in lung function in healthy individuals. Cigarette smoking accelerates lung function decline over time, suggesting smoking accelerates aging of the lung. Based on this data, we hypothesized that cigarette smoking accelerates the aging of the small airway epithelium, the cells that take the initial brunt of inhaled toxins from the cigarette smoke and one of the primary sites of pathology associated with cigarette smoking. Using the sensitive molecular parameters of aging-related gene expression and telomere length, the aging process of the small airway epithelium was assessed in age matched healthy nonsmokers and healthy smokers with no physical manifestation of lung disease or abnormalities in lung function. Analysis of a 73 gene aging signature demonstrated that smoking significantly dysregulates 18 aging-related genes in the small airway epithelium. In an independent cohort of male subjects, smoking significantly reduced telomere length in the small airway epithelium of smokers by 14% compared to nonsmokers. These data provide biologic evidence that prior to the clinical manifestation of lung disease; smoking accelerates aging of the small airway epithelium.
Smoking accelerates aging of the small airway epithelium.
No sample metadata fields
View SamplesMDA-MB-231 cells transfected with pcDNA-vector or pcDNA-LKB1 were analyzed for changes in gene expression. Results provide insight into genes regulated by LKB1 signaling with implications in tumor and metastasis suppression in breast cancer. Overall design: 4 samples, duplicates of -vector and -LKB1 stable cell lines
Regulation of triple-negative breast cancer cell metastasis by the tumor-suppressor liver kinase B1.
No sample metadata fields
View SamplesRegulatory T (Treg) maintain the tumor microenvironment in an immunosuppressive state preventing effective anti-tumor immune response. A possible strategy to overcome Treg cell suppression focuses on OX40, a costimulatory molecule expressed constitutively by Treg cells while induced in activated effector T (Teff) cells. OX40 stimulation by the agonist mAb OX86 inhibits Treg cell suppression and boosts Teff cell activation. Here we uncover the mechanisms underlying the therapeutic activity of OX86 treatment dissecting its distinct effects on Treg and on effector memory T (Tem) cells, which are the most abundant CD4+ populations strongly expressing OX40 at the tumor site. In response to OX86, tumor-infiltrating Treg cells produced significantly less interleukin 10 (IL-10), possibly in relation to a decrease in the transcription factor IRF1. Tem cells responded to OX86 by upregulating surface CD40L expression, providing a licensing signal to dendritic cells (DCs). The CD40L/CD40 axis was required for Tem cell-mediated in vitro DC maturation and in vivo DC migration. Accordingly, OX86 treatment was no longer therapeutic in CD40 KO mice. In conclusion, following OX40 stimulation, blockade of Treg cell suppression and enhancement of the Tem cell adjuvant effect both concurred to free DCs from immunosuppression and to activate the immune response against the tumor.
Intratumor OX40 stimulation inhibits IRF1 expression and IL-10 production by Treg cells while enhancing CD40L expression by effector memory T cells.
No sample metadata fields
View Samplesdrl expression initiates during gastrulation and condenses as a band of cells at the prospective lateral embryo margin. In late epiboly, drl:EGFP is detectable as a band of scattered EGFP-fluorescent cells; after gastrulation, drl:EGFP-positive cells coalesce at the embryo margin that then in somitogenesis break down into the anterior and posterior lateral plate with subsequent cell migrations that form the posterior vascular/hematopoietic stripes and the anterior cardiovascular and myeloid precursors.
Chamber identity programs drive early functional partitioning of the heart.
Age, Specimen part
View SamplesThe aim of this experiment was to investigate the role of MIF during wound healing using BALB/C MIF null mice and in the context of reduced estrogen-associated impaired healing using ovariectomized mice (a mouse model of age-associated delayed healing). Ageing is associated with delayed cutaneous wound healing resulting from reduced estrogen levels. Macrophage migration inhibitory factor (MIF - NCBI RefSeq: NM_010798) is thought to mediate the effects of estrogen on wound healing. Gene expression was compared between wounds from ovariectomized MIF null mice and controls.
Macrophage migration inhibitory factor: a central regulator of wound healing.
Sex, Age, Specimen part, Subject
View SamplesWe report the application of ultrashort metabolic labeling of RNA for high-throughput profiling of RNA processing in Drosophila S2 cells. Overall design: Examination of 3 different labeling timepoints in Drosophila S2 cells.
The kinetics of pre-mRNA splicing in the <i>Drosophila</i> genome and the influence of gene architecture.
Cell line, Subject
View SamplesAlas2 gene encodes the rate-limiting enzyme in heme biosynthesis. CRISPR/Cas9-mediated ablation of two Alas2 intronic cis-elements strongly reduced GATA-1-induced Alas2 transcription, heme biosynthesis, and GATA-1 regulation of other vital constituents of the erythroid cell transcriptome. Bypassing Alas2 function in Alas2 cis-element-mutant (double mutant) cells by providing its catalytic product 5-aminolevulinic acid (5-ALA) rescued heme biosynthesis and the GATA-1-dependent genetic network. We discovered a GATA factor- and heme-dependent circuit that establishes the erythroid cell transcriptome. Overall design: G1E-ER-GATA-1 WT and double mutant cells were examined. Untreated WT, beta-estradiol-treated WT, beta-estradiol-treated double-mutant, and beta-estradiol/5-ALA-treated double-mutant cells were subjected to RNA-seq.
Mechanism governing heme synthesis reveals a GATA factor/heme circuit that controls differentiation.
Treatment, Subject
View SamplesUsing Affymetrix microarray technology we analyzed the gene expression profiles of the most important pathological categories of bladder cancer in order to detect potential marker genes. Applying an unsupervised cluster algorithm we observed clear differences between tumor and control samples, as well as between superficial and muscle invasive tumors. According to cluster results, the T1 high grade tumor type presented a global genetic profile which could not be distinguished from invasive cases. We described a new measure to classify differentially expressed genes and we compared it against the B-rank statistic as a standard method. According to this new classification method, the biological functions overrepresented in top differentially expressed genes when comparing tumor versus control samples were associated with growth, differentiation, immune system response, communication, cellular matrix and enzyme regulation. Comparing superficial versus invasive samples, the most important overrepresented biological category was growth and, specifically, DNA synthesis and mitotic cytoskeleton. On the other hand, some under expressed genes have been clearly related to muscular tissue contamination in control samples. Finally, we demonstrated that a pool strategy could be a good option to detect the best differentially expressed genes between two compared conditions.
DNA microarray expression profiling of bladder cancer allows identification of noninvasive diagnostic markers.
No sample metadata fields
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