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GSE21862
Homo sapiens
144 Downloadable Samples
Illumina humanRef-8 v2.0 expression beadchip
Description
Human toxicogenomic studies to date have been of limited size, have mainly addressed exposures at the upper end of typical ranges of human exposure, and have often lacked precise, individual estimates of exposure. Previously, we identified genes associated with exposure to high (>10 ppm) levels of the leukemogen, benzene, through transcriptomic analyses of blood cells from small numbers of occupationally exposed workers. Here, we have expanded the study to 125 workers exposed to a wide range of benzene levels, including <1 ppm. Study design, and analysis with a mixed effects model, removed sources of biological and experimental variability and revealed highly significant widespread perturbation of gene expression at all exposure levels. Benzene is an established cause of acute myeloid leukemia (AML), and may cause one or more lymphoid malignancies in humans. Interestingly, acute myeloid leukemia was among the most significant pathways impacted by benzene exposure in the present study. Further, at most exposure levels, immune response pathways including T cell receptor signaling, B cell receptor signaling, and Toll like receptor signaling were impacted, providing support for the biological plausibility of an association between lymphoma and benzene exposure. We also identified a 16-gene expression signature modified by all levels of benzene exposure, comprising genes with roles in immune response, inflammatory response, cell adhesion, cell-matrix adhesion, and blood coagulation. Overall, these findings support, and expand upon, our current understanding of the mechanisms by which benzene may induce hematotoxicity, leukemia and lymphoma. Furthermore, this study shows that with good study design and analysis, transcriptome profiling of the blood of chemically-exposed humans can identify relevant biomarkers across a range of exposures and inform about potential associations with disease risks.
Publication Title
Global gene expression profiling of a population exposed to a range of benzene levels.
Sample Metadata Fields
Sex, Age, Subject
View Samples- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Chromosomal rearrangements involving the mixed-lineage leukemia (MLL) gene occur in primary and treatment-related leukemias, and confer a poor prognosis. Studies based primarily on mouse models have substantially advanced our understanding of MLL leukemia pathogenesis, but often employ supra-physiologic oncogene expression with uncertain implications for human leukemia. Genome editing using site-specific nucleases provides a powerful new technology for gene modification to potentially model human disease, however this approach has not been used to recreate acute leukemia in human cells of origin comparable to disease observed in patients. We applied TALEN-mediated genome editing to generate endogenous MLL-AF9 and MLL-ENL oncogenes through insertional mutagenesis in primary human hematopoietic stem and progenitor cells (HSPCs) derived from human umbilical cord blood. Engineered HSPCs displayed altered in vitro growth potentials and induced acute leukemias following transplantation in immuno-compromised mice at a mean latency of 14.5 weeks. The leukemias displayed phenotypic and morphologic similarities with patient leukemia blasts including a subset with mixed phenotype, a distinctive feature seen in clinical disease. The leukemic blasts expressed an MLL-associated transcriptional program with elevated levels of crucial MLL target genes, displayed heightened sensitivity to DOT1L inhibition, and demonstrated increased oncogenic potential ex vivo and in secondary transplant assays. Thus, genome editing to create endogenous MLL oncogenes in primary human HSPCs faithfully models acute MLL-rearranged leukemia and provides an experimental platform for prospective studies of leukemia initiation and stem cell biology in a genetic subtype of poor prognosis leukemia.
Publication Title
MLL leukemia induction by genome editing of human CD34+ hematopoietic cells.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 678 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
BACKGROUND: In patients with suspicious pulmonary lesions, bronchoscopy is frequently non-diagnostic. This often results in additional invasive testing, including surgical biopsy, although many patients have benign disease. We sought to validate an airway gene-expression classifier for lung cancer in patients undergoing diagnostic bronchoscopy. METHODS: Two multicenter prospective studies (AEGIS 1 and 2) enrolled 1357 current or former smokers undergoing bronchoscopy for suspected lung cancer. Bronchial epithelial cells were collected from normal appearing mucosa in the mainstem bronchus during bronchoscopy. Patients without a definitive diagnosis from bronchoscopy were followed for 12 months. A gene-expression classifier was used to assess the risk of lung cancer, and its performance was evaluated. RESULTS: A total of 298 patients from AEGIS 1 and 341 from AEGIS 2 met criteria for analysis. Bronchoscopy was non-diagnostic for cancer in 272 of 639 patients (43%; 95%CI, 39-46%). The gene expression classifier correctly identified 431 of 487 patients with cancer (89% sensitivity; 95%CI, 85-91%), and 72 of 152 patients without cancer (47% specificity; 95%CI, 40-55%). The combination of the classifier and bronchoscopy had a sensitivity of 97% (95%CI, 95-98%), which was independent of size, location, stage, and histological subtype of lung cancer. In patients with an intermediate pre-test risk (10-60%) of lung cancer, the NPV of the classifier was 91% (95%CI 75-98%). CONCLUSIONS: In patients with an intermediate risk of lung cancer and a non-diagnostic bronchoscopy, a gene-expression classification of low-risk warrants consideration of a more conservative diagnostic approach that could reduce unnecessary invasive testing in patients with benign disease.
Publication Title
A Bronchial Genomic Classifier for the Diagnostic Evaluation of Lung Cancer.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 103 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Mutations within the catalytic domain of the histone methyltransferase (HMT) EZH2 have been identified in subsets of Non-Hodgkin Lymphoma (NHL) patients. These genetic alterations are hypothesized to confer an oncogenic dependency on EZH2 enzymatic activity in these cancers. We previously reported the discovery of a potent, selective, S-adenosyl-methionine-competitive and orally bioavailable small molecule inhibitor of EZH2, EPZ-6438. EPZ-6438 selectively inhibits intracellular lysine 27 of histone H3 (H3K27) methylation in a concentration- and time-dependent manner in both EZH2 wild type and mutant lymphoma cells. Inhibition of H3K27 trimethylation (H3K27Me3) led to selective cell killing of human lymphoma cell lines bearing EZH2 catalytic domain point mutations. Treatment of xenograft-bearing mice with EPZ-6438 leads to dose-dependent tumor growth inhibition and eradication of genetically altered NHL with correlative diminution of H3K27Me3 levels in tumors and selected normal tissues. Mice dosed orally with EPZ-6438 for 28 days remained tumor free for up to 63 day after stopping compound treatment in two EZH2 mutant xenograft models. These data confirm the dependency of mutant NHL on EZH2 activity and portend the utility of EZH2-targeted drugs for the treatment of these genetically defined cancers.
Publication Title
Selective inhibition of EZH2 by EPZ-6438 leads to potent antitumor activity in EZH2-mutant non-Hodgkin lymphoma.
Sample Metadata Fields
Cell line, Time
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Null mutations in the SAL1 protein, a bi-functional protein with inositol polyphosphate-1-phosphotase activity and nucleosidase activity, result in mutants with altered leaf morphology, delayed growth and tolerance to drought stress. This experiment examines the gene expression of two SAL1 mutants, alx8 in the Col-0 background and fry1-1 in the C24 background, under normal growth conditions. In brief, RNA was extracted from the leaves of three plants of each mutant and their respective ecotypes two hours after lights on. Plants were grown under normal conditions for 5 weeks before harvesting. Each array represent a single biological replicate.
Publication Title
The nucleotidase/phosphatase SAL1 is a negative regulator of drought tolerance in Arabidopsis.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 49 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Glaucoma is a common ocular disorder that is a leading cause of blindness worldwide. It is characterized by the dysfunction and loss of retinal ganglion cells (RGCs). Although many studies have implicated various molecules in glaucoma, no mechanism has been shown to be responsible for the earliest detectable damage to RGCs and their axons in the optic nerve. Here, we show that the leukocyte transendothelial migration pathway is activated in the optic nerve head at the earliest stages of disease in an inherited mouse model of glaucoma. This resulted in proinflammatory monocytes entering the optic nerve prior to detectable neuronal damage. A 1-time x-ray treatment prevented monocyte entry and subsequent glaucomatous damage. A single x-ray treatment of an individual eye in young mice provided that eye with long-term protection from glaucoma but had no effect on the contralateral eye. Localized radiation treatment prevented detectable neuronal damage and dysfunction in treated eyes, despite the continued presence of other glaucomatous stresses and signaling pathways. Injection of endothelin-2, a damaging mediator produced by the monocytes, into irradiated eyes, combined with the other glaucomatous stresses, restored neural damage with a topography characteristic of glaucoma. Together, these data support a model of glaucomatous damage involving monocyte entry into the optic nerve. Genome-wide assessment of gene expression changes was performed in DBA/2J-Gpnmb+, DBA/2J mice and irradiated DBA/2J mice at 8.5 and 10.5 months of age.
Publication Title
Radiation treatment inhibits monocyte entry into the optic nerve head and prevents neuronal damage in a mouse model of glaucoma.
Sample Metadata Fields
Sex
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In theses experimetns we have analized the differential gene expression profile in human trabecular meshwork cells phagocytically challenged to E. coli and pigment under physiological and oxidative stress conditions using affymetrix microarrays
Publication Title
Up-regulated expression of extracellular matrix remodeling genes in phagocytically challenged trabecular meshwork cells.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430A 2.0 Array (mouse430a2)
Description
The transmission of information about the photic environment to the circadian clock involves a complex array of neurotransmitters, receptors, and second messenger systems. Using laser capture microscopy and microarray analysis, a population of genes rapidly induced by light in the suprachiasmatic nucleus is identified.
Publication Title
Identification of novel light-induced genes in the suprachiasmatic nucleus.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 14 Downloadable Samples
IlluminaHiSeq2000
Description
Although recent evidence suggests that overlapping sense/antisense transcription is a common feature in higher eukaryotes, the possibility that overlapping transcripts could interact to each other and bear a specific biological function has not been explored. Here we show that a plethora of sense/antisense transcript pairs are co-expressed from 8q24.21 within the same cell and acquire a stable double-stranded RNA conformation. Interestingly, these molecules display predominantly nuclear localization and establish specific interactions with nuclear components. A detailed characterization of a particular sense/antisense pair (ndsRNA-2a) revealed that this molecule displays differential localization throughout the cell cycle, interacts with RCC1 and RAN and through the latter with the mitotic RANGAP1-SUMO1/RANBP2 complex. Notably, an increased number of bi/multi-nucleated cells and chromatin bridges were observed upon ndsRNA-2a overexpression, whereas strand-specific ndsRNA-2a knockdown leads to mitotic catastrophe and cell death. This suggests a functional role of ndsRNA-2a in cell cycle progression that critically requires its double stranded nature. Finally, the identification of hundreds of sense/antisense transcripts pairs harboring ndsRNA profile signatures and their regulation by cellular cues suggests that ndsRNAs constitute a novel class of regulatory molecules that are likely to be involved in a plethora of biological processes. Overall design: PLB985 long (3x datasets) and small (3x datasets) strand specific RNA-Seq for captured RNAs. Global PLB985 for long (2x datasets) and small RNAs (2x datasets). Global libraries for EtOH (vehicle) treated (1x dataset) or retinoic acid induced differentiated PLB985 cells (1x dataset).
Publication Title
Human cells contain natural double-stranded RNAs with potential regulatory functions.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 36 Downloadable Samples
- Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
Determination of gene expression changes in hindlimb muscle (gastrocnemius/soleus) of mdx (dystrophin-deficient) mice at postnatal ages 7, 14, 23, 28, 56, and 112.
Publication Title
Dissection of temporal gene expression signatures of affected and spared muscle groups in dystrophin-deficient (mdx) mice.
Sample Metadata Fields
No sample metadata fields
View Samples