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GSE108607
Homo sapiens
10 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Luminal breast cancers express estrogen (ER) and progesterone (PR) receptors, and respond to endocrine therapies. However, some ER+PR+ tumors display intrinsic or acquired resistance, possibly related to PR. Two PR isoforms, PR-A and PR-B, regulate distinct gene subsets that may differentially influence tumor fate. A high PR-A:PR-B ratio is associated with poor prognosis and tamoxifen resistance. We speculate that excessive PR-A marks tumors that will relapse early. Here we address mechanisms by which PR-A regulate transcription, focusing on SUMOylation. We use receptor mutants and synthetic promoter/reporters to show that SUMOylation deficiency or the deSUMOylase SENP1 enhance transcription by PR-A, independent of the receptors dimerization interface or DNA binding domain. De-SUMOylation exposes the agonist properties of the antiprogestin RU486. Thus, on synthetic promoters, SUMOylation functions as an independent brake on transcription by PR-A. What about PR-A SUMOylation of endogenous human breast cancer genes? To study these, we used gene expression profiling. Surprisingly, PR-A SUMOylation influences progestin target genes differentially, with some upregulated, others downregulated, and others unaffected. Hormone-independent gene regulation is also PR-A SUMOylation dependent. Several SUMOylated genes were analyzed in clinical breast cancer database. In sum, we show that SUMOylation does not simply repress PR-A. Rather, it regulates PR-A activity in a target selective manner including genes associated with poor prognosis, shortened survival, and metastasis.
Publication Title
SUMOylation Regulates Transcription by the Progesterone Receptor A Isoform in a Target Gene Selective Manner.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
We sought to identify the carcinogenic mechanisms involved in RKO cell line with no evidence of activated -catenin/TCF regulated transcription, by comparison its gene expression profile to that of group of colorectal cancer cell lines selected to be mismatch repair
Publication Title
The Role of Chromosomal Instability and Epigenetics in Colorectal Cancers Lacking β-Catenin/TCF Regulated Transcription.
Sample Metadata Fields
Cell line
View Samples- Rattus norvegicus
- 4 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Psychological, psychosocial and physical stress are major risk factors, which enhance the development of sporadic late-onset Alzheimer`s disease. The chronic unpredictable mild stress model mimics those risk factors and triggers signs of neurodegeneration and neuropathological features of sporadic AD such as tau hyperphosphorylation and enhanced amyloid beta generation. The study investigated the impact of chronic unpredictable mild stress on signs of neurodegeneration by analyzing hippocampal gene expression with whole genome microarray gene expression profiling.
Publication Title
Inhibition of ACE Retards Tau Hyperphosphorylation and Signs of Neuronal Degeneration in Aged Rats Subjected to Chronic Mild Stress.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Rattus norvegicus
- 16 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
The initial segment of the epididymis is vital for male fertility, therefore, it is important to understand the mechanisms that regulate this important region. Deprival of testicular luminal fluid factors/lumicrine factors from epididymis, a subset of cells within the initial segment undergo apoptosis. In this study, microarray analyses was used to examine early changes in the downstream signal transduction pathways following the loss of lumicrine factors, and we discovered the following cascade of events leading to loss of protection and eventual apoptosis. First, mRNA expression of several key components of ERK pathway decreased sharply after 6 hours of loss protection from testicular lumicrine factors. After 12 hours, the levels of mRNA expression of STAT and NF-B pathways components increased, mRNA expression of genes encoding cell cycle inhibitors increased. After 18 hours of loss protection from testicular lumicrine factors, apoptosis was observed in the initial segment. In conclusion, testicular lumicrine factors protect the cells of the initial segment by activating ERK pathway, repressing STAT and NF-B pathways, and preventing a cascade of reactions leading to apoptosis.
Publication Title
Testicular lumicrine factors regulate ERK, STAT, and NFKB pathways in the initial segment of the rat epididymis to prevent apoptosis.
Sample Metadata Fields
Sex, Specimen part, Time
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Differential gene expression analysis of oesophageal cells stimulated with a low pH environment. Study designed to identify pathways involved in progression of gastro-oesophageal reflux disease through Barrett's oesophagus to adenocarcinoma. Identified many subsets of genes with involvement in pathogenesis.
Publication Title
Low pH induces co-ordinate regulation of gene expression in oesophageal cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 3 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Targeted therapies have provided advantages to cancer patients, but these therapies are limited by differential responses and developed resistance.
Publication Title
Activation of the AXL kinase causes resistance to EGFR-targeted therapy in lung cancer.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 22 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
DNA methyltransferase 3A (DNMT3A) is frequently mutated in hematological cancers; however, the underlying oncogenic mechanism remains elusive. Here, we report that DNMT3A mutational hotspot at Arg882 (DNMT3A R882H) cooperates with NRAS mutation to transform hematopoietic stem/progenitor cells and induce acute leukemia development. Mechanistically, DNMT3A R882H directly binds to and potentiates transactivation of stemness genes critical for leukemogenicity including Meis1, Mn1 and Hoxa gene cluster. DNMT3A R882H induces focal epigenetic alterations, including CpG hypomethylation and concurrent gain of active histone modifications, at cis-regulatory elements such as enhancers to facilitate gene transcription. CRISPR/Cas9-mediated ablation of a putative Meis1 enhancer carrying DNMT3A R882H-induced DNA hypomethylation impairs Meis1 expression. Importantly, DNMT3A R882H-induced gene expression programs can be repressed through Dot1l inhibition, providing an attractive therapeutic strategy for DNMT3A-mutated leukemias.
Publication Title
Epigenetic Perturbations by Arg882-Mutated DNMT3A Potentiate Aberrant Stem Cell Gene-Expression Program and Acute Leukemia Development.
Sample Metadata Fields
Specimen part, Cell line, Treatment, Time
View Samples- Mus musculus
- 12 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
DNA Methyltransferase 3A (DNMT3A) is frequently mutated in various hematopoietic malignancies; however, the underlying oncogenic mechanisms remain elusive. Here, we report that DNMT3A mutational hotspot at Arg882 (i.e., DNMT3A-R882H) cooperates with constitutively activated RAS in transforming murine hematopoietic stem/progenitor cells (HSPCs) ex vivo and inducing acute leukemias in vivo. DNMT3A-R882H potentiates aberrant transactivation of stemness gene expression programs, notably transcription factors Meis1, Hox-A, Mn1 and Mycn. Mechanistically, R882-mutated DNMT3A directly binds to cis-regulatory elements of these genes and induces focal CpG hypomethylation reminiscent of what was seen in human leukemias bearing DNMT3A R882 mutation. Furthermore, DNMT3A-R882H induced DNA hypomethylation facilitates gene enhancer/promoter activation and recruitment of Dot1l-associated transcription elongation machineries. Inactivation of Dot1l represses DNMT3AR882H-mediated stem cell gene dysregulation and acute leukemogenicity.
Publication Title
Epigenetic Perturbations by Arg882-Mutated DNMT3A Potentiate Aberrant Stem Cell Gene-Expression Program and Acute Leukemia Development.
Sample Metadata Fields
Specimen part, Time
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Aberrant signal transduction contributes substantially to leukemogenesis. The Janus kinase 1 (JAK1) gene encodes a cytoplasmic tyrosine kinase that noncovalently associates with a variety of cytokine receptors and plays a nonredundant role in lymphoid cell precursor proliferation, survival, and differentiation. Somatic mutations in JAK1 occur in individuals with acute lymphoblastic leukemia (ALL). JAK1 mutations were more prevalent among adult subjects with the T cell precursor ALL, where they accounted for 18% of cases, and were associated with advanced age at diagnosis, poor response to therapy, and overall prognosis
Publication Title
ALL-associated JAK1 mutations confer hypersensitivity to the antiproliferative effect of type I interferon.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
DNA Methyltransferase 3A (DNMT3A) is frequently mutated in various hematopoietic malignancies; however, the underlying oncogenic mechanisms remain elusive. Here, we report that DNMT3A mutational hotspot at Arg882 (DNMT3A-R882H) cooperates with constitutively activated RAS in transforming murine hematopoietic stem/progenitor cells (HSPCs) ex vivo and inducing acute leukemias in vivo. DNMT3A-R882H potentiates aberrant transactivation of stemness gene expression programs, notably transcription factors Meis1, Hox-A, Mn1 and Mycn. Mechanistically, R882-mutated DNMT3A directly binds to cis-regulatory elements of these genes and induces focal CpG hypomethylation reminiscent of what was seen in human leukemias bearing DNMT3A R882 mutation. Furthermore, DNMT3A-R882H induced DNA hypomethylation facilitates gene enhancer/promoter activation and recruitment of Dot1l-associated transcription elongation machineries. Inactivation of Dot1l represses DNMT3AR882H-mediated stem cell gene dysregulation and acute leukemogenicity.
Publication Title
Epigenetic Perturbations by Arg882-Mutated DNMT3A Potentiate Aberrant Stem Cell Gene-Expression Program and Acute Leukemia Development.
Sample Metadata Fields
Cell line, Treatment
View Samples