Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA87847 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The transcription factor GATA3 is a favorable prognostic indicator in estrogen receptor-M-NM-1 (ERM-NM-1)-positive breast tumors in which it participates with ERa and FOXA1 in a complex transcriptional regulatory program driving tumor growth. Paradoxically, GATA3 mutations are frequent in breast cancer and have been classified as drivers. To elucidate the contribution(s) of GATA3 alterations to oncogenesis, we studied two breast cancer cell lines, MCF7, which carries a heterozygous frameshift mutation in the second zinc finger of GATA3, and T47D, wild-type at this locus. Heterozygosity for the truncating mutation conferred protection from regulated turnover of GATA3, ERa and FOXA1 following estrogen stimulation. Thus, mutant GATA3 uncouples protein-level regulation of master regulatory transcription factors from hormone action. Consistent with increased protein stability, ChIP-seq profiling identified stronger accumulation of GATA3 in cells bearing the mutation, albeit with a similar distribution across the genome. We propose that this specific, cancer-derived mutation in GATA3 deregulates physiologic protein turnover, stabilizes GATA3 binding across the genome and modulates the response of mammary epithelial cells to hormone signaling, thus conferring a selective growth advantage. Genome-wide mapping of GATA3 in two cell lines. There were two biological replicates and unchipped (input) DNA was used as reference.
2014-04-01 | E-GEOD-51274 | biostudies-arrayexpress
Project description:The transcription factor GATA3 is a favorable prognostic indicator in estrogen receptor-α (ERα)-positive breast tumors in which it participates with ERa and FOXA1 in a complex transcriptional regulatory program driving tumor growth. Paradoxically, GATA3 mutations are frequent in breast cancer and have been classified as drivers. To elucidate the contribution(s) of GATA3 alterations to oncogenesis, we studied two breast cancer cell lines, MCF7, which carries a heterozygous frameshift mutation in the second zinc finger of GATA3, and T47D, wild-type at this locus. Heterozygosity for the truncating mutation conferred protection from regulated turnover of GATA3, ERa and FOXA1 following estrogen stimulation. Thus, mutant GATA3 uncouples protein-level regulation of master regulatory transcription factors from hormone action. Consistent with increased protein stability, ChIP-seq profiling identified stronger accumulation of GATA3 in cells bearing the mutation, albeit with a similar distribution across the genome. We propose that this specific, cancer-derived mutation in GATA3 deregulates physiologic protein turnover, stabilizes GATA3 binding across the genome and modulates the response of mammary epithelial cells to hormone signaling, thus conferring a selective growth advantage.
2014-04-01 | GSE51274 | GEO
Project description:The GATA3 transcription factor is one of the most frequently mutated genes in breast cancer. Heterozygous mutations, largely frameshifting, are seen in 15% of estrogen receptor positive breast cancers, the subtype in which these mutations are almost exclusively found. Mouse studies have shown that Gata3 is critical for breast development and that GATA3 gene dosage affects breast tumor progression. Human patient data have shown that high Gata3 expression, a feature of luminal subtype breast cancers, is associated with a better prognosis. Although the frequency of GATA3 mutation suggests an important role in breast cancer development or progression, there is little understanding of how mutations in GATA3 affect its function in luminal breast epithelial cells and what gene expression changes result as a consequence of the mutations. Here, using gene editing, we have created two sets of isogenic human luminal breast cancer cell lines with and without a truncating GATA3 mutation. GATA3 mutation enhanced tumor growth in vivo but did not affect sensitivity to clinically used hormonal therapies or chemotherapeutic agents. We identified genes upregulated and downregulated in GATA3 mutant cells, a subset of which was concordantly differentially expressed in GATA3 mutant primary luminal breast cancers. Addback of mutant GATA3 recapitulated mutation-specific gene expression changes and enhanced soft agar colony formation, suggesting a gain of function for the mutant protein.
2018-01-12 | GSE101780 | GEO
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
2010-09-25 | GSE24338 | GEO
Project description:Breast tumor specific mutation in GATA3 impacts protein stability and genomic location
| PRJNA222284 | ENA
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
2011-02-19 | GSE20463 | GEO
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
| S-EPMC2531291 | biostudies-literature
Project description:RNA extracted at 240min. Samples are rRNA depleted. Expression measurement of Homo sapiens genes.
2019-07-31 | GSE114179 | GEO
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
2011-08-25 | GSE23936 | GEO
Project description:We have sequenced miRNA libraries from human embryonic, neural and foetal mesenchymal stem cells. We report that the majority of miRNA genes encode mature isomers that vary in size by one or more bases at the 3’ and/or 5’ end of the miRNA. Northern blotting for individual miRNAs showed that the proportions of isomiRs expressed by a single miRNA gene often differ between cell and tissue types. IsomiRs were readily co-immunoprecipitated with Argonaute proteins in vivo and were active in luciferase assays, indicating that they are functional. Bioinformatics analysis predicts substantial differences in targeting between miRNAs with minor 5’ differences and in support of this we report that a 5’ isomiR-9-1 gained the ability to inhibit the expression of DNMT3B and NCAM2 but lost the ability to inhibit CDH1 in vitro. This result was confirmed by the use of isomiR-specific sponges. Our analysis of the miRGator database indicates that a small percentage of human miRNA genes express isomiRs as the dominant transcript in certain cell types and analysis of miRBase shows that 5’ isomiRs have replaced canonical miRNAs many times during evolution. This strongly indicates that isomiRs are of functional importance and have contributed to the evolution of miRNA genes
2014-08-06 | GSE58734 | GEO