Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA150935 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Hypoxia is one of the major driving forces mediating tumor angiogenesis, aggressiveness, as well as resistance to chemo- and radiotherapy. It has also been suggested to play important roles in stem cell maintenance for both normal and cancer tissues. However, the mechanisms by which hypoxia-driven epigenetic changes modulate tumorigenesis remain poorly understood. As the histone H3 lysine 9 (H3K9) demethylase Jmjd1a and methyltransferase G9a are upregulated downstream targets of hypoxia, we focused on these two catalytically opposing epigenetic modifiers to address this question. Through the use of homozygous Jmjd1a and G9a knockout mouse embryonic stem (ES) cells, we found that Jmjd1a was not required for stem cell self-renewal and that anti-angiogenesis related genes were epigenetically dysregulated in both Jmjd1a- and G9a deficient ES cells under hypoxic conditions, accompanied by corresponding changes in H3K9 dimethylation and H3K4 trimethylation levels in the proximal promoter regions of these target genes. Most importantly, these genetic alterations led to opposing tumor phenotypes: loss of Jmjd1a results in increased tumor growth, whereas loss of G9a produces smaller tumors. These findings provide new insights on the importance of hypoxia signalling in regulating the epigenetic status and expression of angiogenesis genes that promote tumor progression. 63 microarray samples consisting of 7 mouse ES cell lines of which 2 are wild type (control), 2 Jmjd1a knockout, 2 G9a knockout and 1 G9a knockout that was reconstituted for G9a (G9a control). Each cell line and condition was seeded at 3 different densities (2X10^5, 4X10^5 and 6X10^5) in 6 cm dishes to control for the effects of cell confluency on gene expression. 18 hours after plating, the cells were subjected to normoxia (21% O2) for 24 hours (control), normoxia 20 hours followed by hypoxia (1% O2) for 4 hours (acute hypoxia) and 24 hours hypoxia (chronic treatment). Total RNA was harvested from all samples for microarrays after the 24 hour treatments.
2014-07-30 | E-GEOD-35061 | biostudies-arrayexpress
Project description:Hypoxia is one of the major driving forces mediating tumor angiogenesis, aggressiveness, as well as resistance to chemo- and radiotherapy. It has also been suggested to play important roles in stem cell maintenance for both normal and cancer tissues. However, the mechanisms by which hypoxia-driven epigenetic changes modulate tumorigenesis remain poorly understood. As the histone H3 lysine 9 (H3K9) demethylase Jmjd1a and methyltransferase G9a are upregulated downstream targets of hypoxia, we focused on these two catalytically opposing epigenetic modifiers to address this question. Through the use of homozygous Jmjd1a and G9a knockout mouse embryonic stem (ES) cells, we found that Jmjd1a was not required for stem cell self-renewal and that anti-angiogenesis related genes were epigenetically dysregulated in both Jmjd1a- and G9a deficient ES cells under hypoxic conditions, accompanied by corresponding changes in H3K9 dimethylation and H3K4 trimethylation levels in the proximal promoter regions of these target genes. Most importantly, these genetic alterations led to opposing tumor phenotypes: loss of Jmjd1a results in increased tumor growth, whereas loss of G9a produces smaller tumors. These findings provide new insights on the importance of hypoxia signalling in regulating the epigenetic status and expression of angiogenesis genes that promote tumor progression.
2014-07-30 | GSE35061 | GEO
Project description:Histone H3 lysine 9 (H3K9) methylation is an epigenetic mark of transcriptionally repressed chromatin. During mammalian development, H3K9 methylation levels seem to be spatiotemporally regulated by the opposing activities of methyltransferases and demethylases to govern correct gene expression. However, the combination(s) of H3K9 methyltransferase(s) and demethylase(s) that contribute to this regulation and the genes regulated by them remain unclear. Herein, we demonstrate the essential roles of H3K9 demethylases Jmjd1a and Jmjd1b in the embryogenesis and viability control of embryonic stem (ES) cells. Mouse embryos lacking Jmjd1a/Jmjd1b died after implantation. Depletion of Jmjd1a/Jmjd1b in mouse ES cells induced rapid cell death accompanied with a massive increase in H3K9 methylation. Jmjd1a/Jmjd1b depletion induced an increase in H3K9 methylation in the gene-rich regions of the chromosomes, indicating that Jmjd1a/Jmjd1b removes H3K9 methylation marks in the euchromatin. Importantly, the additional disruption of the H3K9 methyltransferase G9a in a Jmjd1a/Jmjd1b-deficient background rescued not only the H3K9 hypermethylation phenotype but also the cell death phenotype. We also found that Jmjd1a/Jmjd1b removes H3K9 methylation marks deposited by G9a in the Oct4 and Ccnd1 loci to activate transcription. In conclusion, Jmjd1a/Jmjd1b ensures ES cell viability by antagonizing G9a-mediated H3K9 hypermethylation in the gene-rich euchromatin.
2018-03-14 | GSE98761 | GEO
Project description:The Hypoxia-Inducible Factors induce the expression of the histone demethylases JMJD1A (KDM3A) and JMJD2B (KDM4B), linking the hypoxic tumor microenvironment to epigenetic mechanisms that may foster tumor progression. This dataset includes expression data obtained from exposing colon carcinoma cells to hypoxia in combination with siRNA-mediated knockdown of the hypoxia-inducible histone demethylases JMJD1A and JMJD2B.
2021-11-03 | GSE166991 | GEO
Project description:Chromatin is dynamically reorganized when DNA replication forks are challenged. However, the process of epigenetic reorganization and its implication for fork stability is poorly understood. Here, we discover a checkpoint regulated cascade of chromatin signaling that activates 5 the histone methyltransferase EHMT2/G9a to catalyze heterochromatin assembly at stressed replication forks. Using biochemical and single molecule chromatin fiber approaches, we show that G9a together with SUV39h1 induces chromatin compaction by accumulating the repressive modifications, H3K9me1/me2/me3, in the vicinity of stressed replication forks. This closed conformation is also favored by the G9a-dependent exclusion of the H3K9-demethylase 10 JMJD1A/KDM3A, which facilitates heterochromatin disassembly upon fork restart. Untimely heterochromatin disassembly from stressed forks by KDM3A enables PRIMPOL access, triggering ssDNA gap formation and sensitizing cells towards chemotherapeutic drugs. These findings may help explaining chemotherapy resistance and poor prognosis observed in cancer patients displaying elevated level of G9a/H3K9me3.
2023-05-12 | PXD041742 | Pride
Project description:The Hypoxia-Inducible Factors induce the expression of the histone demethylases JMJD1A (KDM3A) and JMJD2B (KDM4B), linking the hypoxic tumor microenvironment to epigenetic mechanisms that may foster tumor progression. Using transcript profiling, we have identified genes that are regulated by JMJD1A and JMJD2B in both normoxic and hypoxic conditions in SKOV3ip.1 ovarian cancer cells. This dataset includes expression data obtained from exposing ovarian cancer cells to hypoxia in combination with siRNA-mediated knockdown of the hypoxia-inducible histone demethylases JMJD1A and JMJD2B. These data were used to both identify functional overlap between each histone demethylase, as well as identify effectors of tumor growth mediated by JMJD2B (KDM4B) in normoxia and hypoxia.
2017-03-13 | GSE66894 | GEO
Project description:Epigenetic mechanisms play important roles in the regulation of tumorigenesis, and hypoxia-induced epigenetic changes may be key drivers of the adaptation of cancer cells to the hypoxic microenvironment typical of solid tumors. Previously, we showed that loss-of-function or inhibition of the oncogenic H3K9 methyltransferase G9A attenuates tumor growth and constitutes an important strategy for cancer management. However, the mechanisms by which blockade of G9A leads to a tumor suppressive effect remain poorly understood. Here, we show that G9A is highly expressed in breast cancer compared to normal breast tissue and is associated with poor prognosis in patients, where it may function as a potent oncogenic driver in this cancer type. In agreement with this, G9A inhibition leads to increased cell death, impaired cell migration, reduced cell cycle and downregulated anchorage-independent growth. Interestingly, whole transcriptome analysis revealed that a number of previously non-responsive genes become amenable to hypoxia following G9A inhibition, including many targets that drive cancer cell survival. This was accompanied by the upregulation of the hypoxia inducible factors HIF1A and HIF2A during the use of G9A inhibition to curb cancer cell growth even under normoxic conditions. Therefore, we show that G9A is a key mediator of oncogenic processes in breast cancer cells and cancer therapeutics involving G9A inhibition can be used successfully to attenuate oncogenicity. However, cancer cells mount a survival response via activation of the HIF pathway that may necessitate the additional suppression of HIF signaling for improved efficacy in the eradication of the disease.
2017-12-20 | GSE89891 | GEO
Project description:The Hypoxia-Inducible Factors induce the expression of the histone demethylases JMJD1A (KDM3A) and JMJD2B (KDM4B), linking the hypoxic tumor microenvironment to epigenetic mechanisms that may foster tumor progression. Using transcript profiling, we have identified genes that are regulated in RCC4 with siRNA-mediated knockdown of JMJD1A and JMJD2B. This dataset includes expression data obtained from renal cell Carcinoma being loss or mutation of the von Hippel-Lindau (VHL) tumor suppressor gene combination with siRNA-mediated knockdown of histone demethylases JMJD1A and JMJD2B.
2021-11-03 | GSE167025 | GEO
Project description:Developmental gene expression is defined through cross-talk between the function of transcription factors and epigenetic status including histone modification. Although several known transcription factors play crucial roles in mammalian sex determination, how chromatin regulation contributes to this process is unknown. We observed male-to-female sex reversal in mice lacking the H3K9 demethylase Jmjd1a, and found that Jmjd1a directly regulates expression of the mammalian Y chromosome sex-determining gene Sry, by regulating H3K9me2 marks. These studies reveal a pivotal role for epigenetic regulation in mammalian sex determination, and provide new impetus for identifying additional causes of disorders of sex determination by environmental factors. Gene expression patterns were measured in gonadal somatic cells of Jmjd1a mutant and control embryos at E11.5. Three biological replicates were performed in each group.
2013-08-03 | E-GEOD-49513 | biostudies-arrayexpress
Project description:We report the H3K9me2 distribution profile with ChIP sequencing of postnatal male germ cells. Histone modification levels are dynamically controlled during mammalian spermatogenesis. We found that H3K9 demethylases, Jmjd1a and Jmjd1b catalyze H3K9 demethylation in prospermatogonia. Combined loss of Jmjd1 enzymes disturbed prospermatogonia to spermatogonia transition in mice. To examine a role of Jmjd1 in prospermatogonia to spermatogonia transition, we performed RNA-seq and ChIP-seq analyses using postnatal germ cells at P3 and P7.
2020-06-08 | GSE148054 | GEO