Gene expression profiling of MDA-MB-468 cells following p53-R273H mutant knock-down
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE65967 | GEO | 2016/06/30
SECONDARY ACCESSION(S): PRJNA275589
REPOSITORIES: GEO
Similar Datasets
Project description:A total of 58 genes were up-regulated (> 1.5 fold-change) while 117 genes were down-regulated Microarray experiments were performed in duplicate as follows: MDA-MB-468 cells were transduced with lentiviral shRNA targeting endogenous p53-R273H mutant (p53si-1)or a non-targeting shRNA (NS). Total RNA from cells was extracted using Qiagen RNA isolation kit (Qiagen, Valencia, CA, USA) according to the manufacturersâ protocol. RNA purity was examined by spectrophotometric determination at 260/280 nm. The microarray hybridizations were carried out using the Affymetrix Human Gene 1.0 ST arrays.
2016-06-30 | E-GEOD-65967 | biostudies-arrayexpress
Project description:Mammalian target of rapamycin (mTOR) is a serine/threonine kinase involved in multiple intracellular signaling pathways promoting tumor growth. mTOR is aberrantly activated in a significant portion of breast cancers and is a promising target for treatment. Rapamycin and its analogues are in clinical trials for breast cancer treatment. Patterns of gene expression (metagenes) may also be used to simulate a biologic process of effects of a drug treatment. In this study, we tested the hypothesis that the gene-expression signature regulated by rapamycin could predict disease outcome for patients with breast cancer. Results: Colony formation and sulforhodamine B (IC50 < 1nM) assays, and xenograft animals showed that MDA-MB-468 cells were sensitive to treatment with rapamycin. The comparison of in vitro and in vivo gene expression data identified a signature, termed rapamycin metagene index (RMI), of 31 genes upregulated by rapamycin treatment in vitro as well as in vivo (false discovery rate of 10%). In the Miller dataset, RMI was significantly associated with tumor size or lymph node status. High (>75) percentile) RMI was significantly associated with longer survival (P = 0.015). On multivariate analysis, RMI (P = 0.029), tumor size (P = 0.015) and lymph node status (P = 0.01) were prognostic. In van 't Veer study, RMI was not associated with the time to develop distant metastasis (P = 0.41). In Wang dataset, RMI predicted time to disease relapse (P = 0.09). Conclusions: Rapamycin-regulated gene expression signature predicts clinical outcome in breast cancer. This supports the central role of mTOR signaling in breast cancer biology and provides further impetus to pursue mTOR-targeted therapies for breast cancer treatment. Mol Cancer. 2009 Sep 24;8(1):75. Experiment Overall Design: Rapamycin treatment of MDA-MB-468 breast cancer cell line: Experiment Overall Design: MDA-MB-468 cell line was treated by DMSO (vehicle) and 100 nM rapamycin for 24 hours. We sought to identify differentially expressed genes. Experiment Overall Design: Rapamycin treatment of breast tumor xenografts: Experiment Overall Design: MDA-MB-468 cells were inoculated in the mammary fat pad of female nude mice. When resulting tumor volumes had reached 75-150 mm3, the mice were divided in four groups. Groups 1 and 2 received a single injection of DMSO (vehicle) or rapamycin (15 mg/kg) intraperitoneally and sacrificied 24 h later (1-day groups). Groups 3 and 4 received weekly injections of DMSO or rapamycin for 3 weeks and sacrificied 24 h after the last injection (22-day groups).
| S-ECPF-GEOD-18571 | biostudies-other
Project description:To determine the effect ALDH1A3 expression on global gene expression in MDA-MB-231 cells and MDA-MB-468 cells In MDA-MB-231 cells, ALDH1A3 was overexperssed (have low endogenous levels of ALDH1A3) and compared to MSCV empty vector control. In MDA-MB-468 cells that have high endogenous levels of ALDH1A3, ALDH1A3 expresion was reduced with ALDH1A3 shRNA1 and compared to scramble shRNA control.
| S-ECPF-GEOD-49322 | biostudies-other
Project description:Identifying miRNA-regulated genes is key to understanding miRNA function. However, many miRNA recognition elements (MREs) do not follow canonical seed base-pairing rules, making identification of bona fide targets challenging. Here, we apply an unbiased sequencing-based systems approach to characterize miR-522, a member of the oncogenic primate-specific chromosome 19 miRNA cluster, highly expressed in poorly differentiated cancers. To identify miRNA targets, we sequenced full-length transcripts captured by a biotinylated miRNA mimic. Within these targets, mostly non-canonical MREs were identified by sequencing RNase-resistant fragments (this dataset).
| S-ECPF-MTAB-2119 | biostudies-other
Project description:Mammalian target of rapamycin (mTOR) is a serine/threonine kinase involved in multiple intracellular signaling pathways promoting tumor growth. mTOR is aberrantly activated in a significant portion of breast cancers and is a promising target for treatment. Rapamycin and its analogues are in clinical trials for breast cancer treatment. Patterns of gene expression (metagenes) may also be used to simulate a biologic process of effects of a drug treatment. In this study, we tested the hypothesis that the gene-expression signature regulated by rapamycin could predict disease outcome for patients with breast cancer. Results: Colony formation and sulforhodamine B (IC50 < 1nM) assays, and xenograft animals showed that MDA-MB-468 cells were sensitive to treatment with rapamycin. The comparison of in vitro and in vivo gene expression data identified a signature, termed rapamycin metagene index (RMI), of 31 genes upregulated by rapamycin treatment in vitro as well as in vivo (false discovery rate of 10%). In the Miller dataset, RMI was significantly associated with tumor size or lymph node status. High (>75) percentile) RMI was significantly associated with longer survival (P = 0.015). On multivariate analysis, RMI (P = 0.029), tumor size (P = 0.015) and lymph node status (P = 0.01) were prognostic. In van 't Veer study, RMI was not associated with the time to develop distant metastasis (P = 0.41). In Wang dataset, RMI predicted time to disease relapse (P = 0.09). Conclusions: Rapamycin-regulated gene expression signature predicts clinical outcome in breast cancer. This supports the central role of mTOR signaling in breast cancer biology and provides further impetus to pursue mTOR-targeted therapies for breast cancer treatment. Mol Cancer. 2009 Sep 24;8(1):75.
2009-11-20 | GSE18571 | GEO
Project description:"We have reported that the nuclear protein high mobility group A2 (HMGA2), is required for the induction of EMT by TGF-beta (Thuault et al. J. Cell Biol. 2006). HMGA2 regulates a cohort of transcriptional regulators of the EMT process, such as Snail1 and Twist1 (Thuault et al. J. Biol. Chem. 2008, E-Jean Tan et al. J. Biol. Chem. 2012). Since HMGA2 is a chromatin-associated protein, we expect that it should regulate many genes in addition to the EMT-related factors. The aim of our study is to decipher novel molecular mechanisms that explain how EMT links to the process of tumor-initiating cell self-renewal via the chromatin factor HMGA2. In this experiment, we stably transfected human breast cancer MDA-MB-231 cells with shRNA against HMGA2 and investigated effects of the knock-down on global gene expression using Affymetrix arrays, in order to identify novel downstream players involved in this network. In parallel experiments we also analyzed the phenotypic effects of the HMGA2 knock-down on MDA-MB-231 cell proliferation, survival and inavasiveness."
| S-ECPF-MEXP-3547 | biostudies-other
Project description:The tumor suppressor p53 exerts its role mainly as a transcription factor. The TP53 gene, which encodes the p53 protein, is the most commonly mutated gene in human cancers, particularly triple negative breast cancer (TNBC). Variations in the TP53 gene occur mainly in exons 5-8 and result in missense mutations in the DNA-binding domain of the p53 protein that alter DNA binding specificity. To identify the target genes of mutant p53, we performed chromatin immunoprecipitation followed by DNA microarray (ChIP-chip). Briefly, the TNBC cell line MDA-MB-468 containing the endogenous p53-R273H mutation (the arginine residue at position 273 is mutated to a histidine) was cross-linked with 1% formaldehyde and ultrasonically sheared to generate chromatin fragments in a range of 200∼1000 bp. An aliquot of the sheared chromatin was kept as input, and the other chromatin was precipitated with a p53 monoclonal antibody. DNA was purified from the precipitated chromatin and the unprecipitated chromatin (i.e., input), amplified, and labeled with Cy5 (ChIP DNA) or Cy3 (input DNA). Cy5- and Cy3-labeled DNA samples were cohybridized with the NimbleGen Human ChIP-chip 2.1 M Deluxe Promoter Array. The raw and analyzed data are described in this article. They are useful for identifying target genes and consensus binding motifs of the p53 R273H mutant and for further clarifying the molecular mechanism underlying the oncogenic activity of the p53 mutant.
| S-EPMC10470356 | biostudies-literature
Project description: Not available
| S-EPMC10652264 | biostudies-literature
Project description:A number of studies have indicated that thyroid hormone receptor β1 (TRβ1) functions as a tumor suppressor. TRs mediate transcriptional responses through a highly conserved DNA-binding domain (DBD). A novel rat TRβ isoform (rTRβΔ) was previously identified, in which a novel exon, N (108 bp), is located between exons 3 and 4 within the DBD; this exon represents the only difference between rTRβΔ and rTRβ1. In vitro, rTRβΔ exhibits a stronger tumor-suppressive capacity than rTRβ1, and further analysis revealed a high level of conservation between the rat and human DBD sequences. In the present study, an artificially modified human TRβ1 (m-hTRβ1) was constructed via the introduction of the 108-bp sequence into the corresponding position of the wild-type human TRβ1 (wt-hTRβ1) DBD. An electrophoretic mobility shift assay and transfection experiments confirmed that m-hTRβ1 is functional. Overexpression of m-hTRβ1 inhibits the proliferation of MDA-MB-468 cells in the presence of triiodothyronine by promoting apoptosis, which may be associated with the upregulation of Caspase-3 and Bak gene expression and the activation of the Caspase-3 protein. In addition, the pro-apoptotic effect of m-hTRβ1 was stronger, compared with wt-hTRβ1. These results indicated that m-hTRβ1 may act as a tumor suppressor in MDA-MB-468 cells. These data provided a novel insight into gene therapy for breast cancer.
| S-EPMC6019938 | biostudies-literature
Project description:In this experiment, we generated isogenic carboplatin-resistant MDA-MB-468 cells displaying a 5x increase in IC50 in respect to the parental cell line. We set out to compare the transcriptome of these cell lines, together with MDA-MB-468 cells overexpressing a constitutively active form of beta-catenin to understand underlying transcriptional changes supporting stable carboplatin-tolerance.
2021-07-09 | E-MTAB-10337 | biostudies-arrayexpress