Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA251815 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Glucocorticoids are critical components of combination chemotherapy regimens in pediatric acute lymphoblastic leukemia (ALL). However, the signaling pathways regulating apoptosis in glucocorticoid-treated lymphoid cells remain unclear. In this study, pediatric ALL patient-derived xenograft inherently sensitive to glucocorticoids were exposed to dexamethasone in vivo. Whole-genome GR binding sites and histone acetylation status were detected using chromatin immunoprecipitation sequencing analyses. This provided a global understanding of dexamethasone-induced DNA modulations in ALL cells in vivo, which is likely to be important in the understanding of mechanisms of glucocorticoid response in lymphoid malignancies. One xenograft (ALL-54) was derived from a patient of dexamethasone-good responder. The xenograft was innoculated into 2 NOD/SCID mice, and treated with dexamethasone (15 mg/kg) or vehicle control. Binding of glucocorticoid receptor (GR), histone acetylation and IgG control in spleen-harvest xenograft samples were detected using ChIP-seq.
2014-12-18 | E-GEOD-58266 | biostudies-arrayexpress
Project description:Glucocorticoids are critical components of combination chemotherapy regimens in pediatric acute lymphoblastic leukemia (ALL). However, the signaling pathways regulating apoptosis in glucocorticoid-treated lymphoid cells remain unclear. In this study, pediatric ALL patient-derived xenograft inherently sensitive to glucocorticoids were exposed to dexamethasone in vivo. Whole-genome GR binding sites and histone acetylation status were detected using chromatin immunoprecipitation sequencing analyses. This provided a global understanding of dexamethasone-induced DNA modulations in ALL cells in vivo, which is likely to be important in the understanding of mechanisms of glucocorticoid response in lymphoid malignancies.
2014-12-18 | GSE58266 | GEO
Project description:in vivo dexamethasone-induced gene expression in pediatric acute lymphoblastic leukemia patient-derived xenografts
| PRJNA248171 | ENA
Project description:Glucocorticoids are critical components of combination chemotherapy regimens in pediatric acute lymphoblastic leukemia (ALL). The pro-apoptotic BIM protein is an important mediator of glucocorticoid-induced apoptosis in normal and malignant lymphocytes, while the anti-apoptotic BCL2 confers resistance. The signaling pathways regulating BIM and BCL2 expression in glucocorticoid-treated lymphoid cells remain unclear. In this study, pediatric ALL patient-derived xenografts (PDXs) inherently sensitive or resistant to glucocorticoids were exposed to dexamethasone in vivo. In order to understand the basis for differential in vivo glucocorticoid sensitivity of PDXs, microarray analysis of gene expression was carried out on 5 each of dexamethasone-sensitive and resistant PDXs . This provided a global understanding of dexamethasone-induced signaling cascades in ALL cells in vivo, and especialy identified the genes that are involved in transducing the apoptotic signal, upstream of BIM/BCL2 dynamic interactions.
2014-05-20 | GSE57795 | GEO
Project description:Glucocorticoids are critical components of combination chemotherapy regimens in pediatric acute lymphoblastic leukemia (ALL). The pro-apoptotic BIM protein is an important mediator of glucocorticoid-induced apoptosis in normal and malignant lymphocytes, while the anti-apoptotic BCL2 confers resistance. The signaling pathways regulating BIM and BCL2 expression in glucocorticoid-treated lymphoid cells remain unclear. In this study, pediatric ALL patient-derived xenografts (PDXs) inherently sensitive or resistant to glucocorticoids were exposed to dexamethasone in vivo. In order to understand the basis for differential in vivo glucocorticoid sensitivity of PDXs, microarray analysis of gene expression was carried out on 5 each of dexamethasone-sensitive and resistant PDXs . This provided a global understanding of dexamethasone-induced signaling cascades in ALL cells in vivo, and especialy identified the genes that are involved in transducing the apoptotic signal, upstream of BIM/BCL2 dynamic interactions. ALL xenograft cells were inoculated by tail-vein injection into NOD/SCID mice, and engraftment was monitored weekly. When >70% %huCD45+ engraftment in the peripheral blood was apparent, which occurred 8-10 weeks post-transplantation, mice were treated with either dexamethasone (15 mg/kg) or vehicle control by intra-peritoneal (IP) injection, and culled at 8 hours following the treatment. Cell suspensions of spleens were prepared and mononuclear cells enriched to >97% human by density gradient centrifugation. RNA was extracted using the RNeasy Mini Kit (QIAGEN, Valencia, CA, USA), and RNA samples with integrity number (RIN) > 8.0 were amplified and hybridized onto Illumina HumanWG-6 v3 Expression BeadChips (6 samples/chip). All chips (with associated reagents) were purchased from Illumina, and scanned on the Illumina BeadArray Reader according to the manufacturer’s instructions. Microarray data were analyzed using the online modules in GenePattern. 10 xenografts were derived from patients of 5 dexamethasone-good responder and 5 dexamethasone-poor responder. Each xenograft was innoculated into 5-6 mice, and treated with dexamethasone (15 mg/kg) or vehicle control. In total spleen-harvest xenograft samples from 58 mice were analyzed using microarray.
2014-05-20 | E-GEOD-57795 | biostudies-arrayexpress
Project description:Gene expression in pediatric acute lymphoblastic leukemia patient-derived xenografts
| PRJNA299641 | ENA
Project description:We examined Glucocorticoid receptor binding sites in isolated neonatal cardiomyocytes treated with Dexamethasone (100nM) for 1hr or Ethanol using GR-ChIP-Seq. In addition to determine the change in the resulting transcriptional status of genes we performed RNAseq in cardiomyocytes treated with Dexamethasone (100nM) or Ethanol for 1hr or 24hrs.
2019-08-20 | GSE114766 | GEO
Project description:Synthetic glucocorticoids (GCs), such as dexamethasone and prednisone, remain key components of therapy for patients with lymphoid malignancies. For pediatric patients with acute lymphoblastic leukemia (ALL), response to GCs remains the most reliable prognostic indicator; failure to respond to GC correlates with poor event-free survival. To uncover GC resistance mechanisms, we performed a genome-wide, survival-based short hairpin RNA screen and identified the orphan nuclear receptor estrogen-related receptor-? (ESRRB) as a critical transcription factor that cooperates with the GC receptor (GR) to mediate the GC gene expression signature in mouse and human ALL cells. Esrrb knockdown interfered with the expression of genes that were induced and repressed by GR and resulted in GC resistance in vitro and in vivo. Dexamethasone treatment stimulated ESRRB binding to estrogen-related receptor elements (ERREs) in canonical GC-regulated genes, and H3K27Ac Hi-chromatin immunoprecipitation revealed increased interactions between GR- and ERRE-containing regulatory regions in dexamethasone-treated human T-ALL cells. Furthermore, ESRRB agonists enhanced GC target gene expression and synergized with dexamethasone to induce leukemic cell death, indicating that ESRRB agonists may overcome GC resistance in ALL, and potentially, in other lymphoid malignancies.
2020-07-20 | GSE115363 | GEO
Project description:Glucocorticoids, including dexamethasone and prednisone, are key components of therapy for B-lymphoblastic leukemia (B-ALL) that work through the glucocorticoid receptor (GR). However, glucocorticoids are not effective for all patients, leading to poor outcomes, and the high doses used in chemotherapy cause many toxicities. We have shown that inhibition of the leukocyte restricted PIK3δ is a promising way to specifically enhance glucocorticoids in B-ALL, with the potential to improve outcomes without increasing toxicities. Here, we show that the PI3Kδ inhibitor idelalisib potentiates both prednisolone and dexamethasone in both B-ALL cell lines and primary patient specimens, particularly at sub-saturating doses. Potentiation is partially explained by a widespread enhancement of glucocorticoid gene regulation, including effector genes that drive B-ALL cell death. Idelalisib causes a reduction in direct phosphorylation of GR at S203 and S226. Ablation of these phospho-acceptor sites enhances glucocorticoid potency. Phosphorylation of S226 inhibits GR DNA binding, indicating that PI3Kδ mediated phosphorylation directly inhibits GR function in part though reduction of DNA binding affinity. Thus, PI3Kδ inhibition improves glucocorticoid efficacy in B-ALL in part by decreasing GR phosphorylation and enhancing DNA binding and downstream gene regulation. Identification of this and other contributing mechanisms will help identify patients who can most benefit clinically from this combination therapy.
2022-10-18 | GSE215385 | GEO
Project description:Relapse and acquired drug resistance in T-cell acute lymphoblastic leukemia (T-ALL) remains a significant clinical problem. The current study used a pre-clinical model of induction therapy for pediatric ALL in NOD/SCID mice (Samuels et al Blood Cancer Journal (2014) 4, e232; doi:10.1038/bcj.2014.52) to study the development of drug resistance. We performed transcription profiling by array of human CD45-positive lymphocytes from patients with acute pediatric lymphoblastic leukemia, xenografted in NOD/SCID mice treated with vincristine, daunorubicin, dexamethasone and L-asparagine. Both the primary-patient-derived and xenograft cells were analysed. The VLXD2 treatment regime is described in full in the protocols associated with this submission and in Samuels et al (Blood Cancer Journal (2014) 4, e232; doi:10.1038/bcj.2014.52). This study is an extension of E-MEXP-3916.
2017-05-01 | E-MTAB-4759 | biostudies-arrayexpress