This SuperSeries is composed of the SubSeries listed below.
Integrated transcriptomic and epigenomic analysis of primary human lung epithelial cell differentiation.
Sex, Specimen part, Time
View SamplesAnalysis of gene expression during differentiation of alveolar epithelial type 2 (AT2) cells into AT1 cells. Timepoints taken at Day 0 (AT2 cell), Days 2, 4, and 6 in culture (differentiating) and Day 8 in culture (AT1-like cells).
Integrated transcriptomic and epigenomic analysis of primary human lung epithelial cell differentiation.
Sex, Specimen part, Time
View SamplesDiseases involving the distal lung alveolar epithelium include chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF) and lung adenocarcinoma. Accurate labeling of specific cell types is critical for determining the contribution of each to pathogenesis of these diseases. The distal lung alveolar epithelium is comprised of two cell types, alveolar epithelial type 1 (AT1) and type 2 (AT2) cells. While cell type-specific markers, most prominently surfactant protein C (SFTPC), have allowed detailed studies of AT2 cell differentiation and their roles in disease, studies of AT1 cells have been hampered by lack of genes with expression unique to AT1 cells. To address this, we performed genome-wide expression profiling of multiple rat organs alongside purified rat AT2, AT1 and in vitro differentiated AT1-like cells, resulting in identification of 54 candidate AT1 cell markers. Cross-referencing with genes upregulated in human in vitro differentiated AT1-like cells narrowed the potential list to 18 candidate genes. Testing the top four candidate genes at RNA and protein levels revealed GRAM domain 2 (GRAMD2), a protein of unknown function, as unique to AT1 cells, while SCNN1G within lung is restricted to AT1 cells. RNAseq confirmed that GRAMD2 is transcriptionally silent in human AT2 cells. Immunofluorescence of mouse alveoli verified that GRAMD2 expression is restricted to the plasma membrane of AT1 cells. These new AT1 cell-specific genes, with GRAMD2 as a leading candidate, will enhance AT1 cell isolation, investigation of alveolar epithelial cell differentiation potential, and contribution of AT1 cells to distal lung diseases. Overall design: RNAseq of purified primary human alveolar epithelial type 2 (AT2) and in vitro differentiated type 1 (AT1-like) cells.
Cross-Species Transcriptome Profiling Identifies New Alveolar Epithelial Type I Cell-Specific Genes.
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View SamplesSmoking-associated DNA hypomethylation has been observed in blood cells and linked to lung cancer risk. However, its cause and mechanistic relationship to lung cancer remain unclear. We studied the association between tobacco smoking and epigenome-wide methylation in non-tumor lung (NTL) tissue from 237 lung cancer cases in the Environment And Genetics in Lung cancer Etiology study, using the Infinium HumanMethylation450 BeadChip. We identified seven smoking-associated hypomethylated CpGs (P?<?1.0?×?10-7), which were replicated in NTL data from The Cancer Genome Atlas. Five of these loci were previously reported as hypomethylated in smokers'' blood, suggesting that blood-based biomarkers can reflect changes in the target tissue for these loci. Four CpGs border sequences carrying aryl hydrocarbon receptor binding sites and enhancer-specific histone modifications in primary alveolar epithelium and A549 lung adenocarcinoma cells. A549 cell exposure to cigarette smoke condensate increased these enhancer marks significantly and stimulated expression of predicted target xenobiotic response-related genes AHRR (P?=?1.13?×?10-62) and CYP1B1 (P?<?2.49?×?10-61). Expression of both genes was linked to smoking-related transversion mutations in lung tumors. Thus, smoking-associated hypomethylation may be a consequence of enhancer activation, revealing environmentally-induced regulatory elements implicated in lung carcinogenesis. Overall design: RNAseq of DMSO or cigarette smoke condensate (CSC)-treated A549 human lung adenocarcinoma cells. Cells were treated for either 48 hours or 2 weeks, as indicated.
Epigenome-wide analysis of DNA methylation in lung tissue shows concordance with blood studies and identifies tobacco smoke-inducible enhancers.
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View SamplesHIV-associated dementia (HAD) is a syndrome occurring in HIV-infected patients with advanced disease that likely develops as a result of macrophage and microglial activation as well as other immune events triggered by virus in the central nervous system. The most relevant experimental model of HAD, rhesus macaques exhibiting SIV encephalitis (SIVE), closely reproduces the human disease and has been successfully used to advance our understanding of mechanisms underlying HAD. In this study we integrate gene expression data from uninfected and SIV-infected hippocampus with a human protein interaction network and discover modules of genes whose expression patterns distinguish these two states, to facilitate identification of neuronal genes that may contribute to SIVE/HIV cognitive deficits. Using this approach we identify several downregulated candidate genes and select one, EGR1, a key molecule in hippocampus-related learning and memory, for further study. We show that EGR1 is downregulated in SIV-infected hippocampus and that it can be downregulated in differentiated human neuroblastoma cells by treatment with CCL8, a product of activated microglia. Integration of expression data with protein interaction data to discover discriminatory modules of interacting proteins can be usefully employed to prioritize differentially expressed genes for further study. Investigation of EGR1, selected in this manner, indicates that its downregulation in SIVE may occur as a consequence of the host response to infection, leading to deficits in cognition.
An integrated systems analysis implicates EGR1 downregulation in simian immunodeficiency virus encephalitis-induced neural dysfunction.
Sex
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Post-transplant molecularly defined Burkitt lymphomas are frequently MYC-negative and characterized by the 11q-gain/loss pattern.
Sex, Age, Treatment
View SamplesWe performed genomic and transcriptomic analysis of seven cases of molecular Burkitt lymphoma (mBL) developed in immunosuppressed patients who underwent solid organ transplantation. Interestingly, three cases (43%) were MYC-translocation-negative and revealed the 11q-gain/loss aberration recently identified in 3% of mBL developed in immunocompetent hosts.1 Based on array CGH data, minimal gain and loss regions of 11q (MGR/~4Mb and MLR/~13.5Mb, respectively) were defined and integrative genomic and transcriptomic analysis identified 35 differentially expressed genes, when compared with classic BL. All 16 MGR-dysregulated genes were upregulated, including cancer related USP2, CBL and PAFAH1B2. As expected, all 19 MGL-dysregulated genes were downregulated and two of them, TBRG1 and EI24, are potential tumor suppressor genes. Interestingly, the vast majority of dysregulated 11q23-q25 genes are involved in the MYC and TP53 networks. We hypothesize that the 11q-gain/loss aberration represents a molecular variant of t(8q24/MYC) and affects the same pathological pathways as the MYC oncogene.
Post-transplant molecularly defined Burkitt lymphomas are frequently MYC-negative and characterized by the 11q-gain/loss pattern.
Sex, Age, Treatment
View SamplesHeterosis which is the improved vigor of F1-hybrids compared to their parents is widely exploited in maize (Zea mays L.) breeding to produce elite hybrids of superior yield. The transcriptomes of the maize inbred lines B73 and Mo17 and their reciprocal hybrid offspring were surveyed in the meristematic zone, the elongation zone, cortex and stele tissues of primary roots, prior to the developmental manifestation of heterosis. Single parent expression (SPE) is consistent with the dominance model for heterosis in that it denotes genes that are expressed in only one parent but in both reciprocal hybrids. In primary root tissues, between 1,027 (elongation zone) and 1,206 (stele) SPE patterns were observed. As a consequence, hybrids displayed in each tissue >400 active genes more than either parent. Analysis of tissue-specific SPE dynamics revealed that 1,233 of 2,233 SPE genes displayed SPE in all tissues in which they were expressed while 1,000 SPE genes displayed in at least one tissue a non-SPE pattern. In addition, 64% (17,351/ 27,164) of all expressed genes were assigned to the two subgenomes which are the result of an ancient genome duplication. By contrast, only between 18 and 25% of the SPE genes were assigned to a subgenome suggesting that a disproportionate number of SPE genes are evolutionary young and emerged after genome duplication. We hypothesize that this phenomenon is associated with human selection of favorable maize genotypes which might primarily affect younger genes rather than genes whose functions have been conserved for millions of years.
Nonsyntenic genes drive highly dynamic complementation of gene expression in maize hybrids.
No sample metadata fields
View SamplesTransient expression of two factors, or from Oct4 alone, resulted in efficient generation of human iPSCs. The reprogramming strategy described revealed a potential transcriptional signature for human iPSCs yet retaining the gene expression of donor cells in human reprogrammed cells free of viral and transgene interference.
Transcriptional signature and memory retention of human-induced pluripotent stem cells.
Sex, Specimen part
View SamplesKRAS mutations are present at a high frequency in human cancers. The development of therapies targeting mutated KRAS requires cellular and animal preclinical models. We exploited adeno-associated virus-mediated homologous recombination to insert the KRAS G12D allele in the genome of mouse somatic cells. Heterozygous mutant cells displayed a constitutively active Kras protein, marked morphologic changes, increased proliferation and motility but were not transformed. On the contrary, mouse cells in which we overexpressed the corresponding KRAS cDNA were readily transformed. The levels of Kras activation in knock-in cells were comparable with those present in human cancer cells carrying the corresponding mutation. KRAS-mutated cells were compared with their wild-type counterparts by gene expression profiling, leading to the definition of a "mutated KRAS-KI signature" of 345 genes. This signature was capable of classifying mouse and human cancers according to their KRAS mutational status, with an accuracy similar or better than published Ras signatures. The isogenic cells that we have developed recapitulate the oncogenic activation of Kras occurring in cancer and represent new models for studying Kras-mediated transformation. Our results have implications for the identification of human tumors in which the oncogenic KRAS transcriptional response is activated and suggest new strategies to build mouse models of tumor progression.
Knock-in of oncogenic Kras does not transform mouse somatic cells but triggers a transcriptional response that classifies human cancers.
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