In vitro prednisolone resistance signature in MLL-rearranged infant ALL
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ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Jill Spijkers-Hagelstein
PROVIDER: E-GEOD-32962 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Acute Lymphoblastic Leukemia (ALL) in infants (<1 year) is characterized by a poor prognosis and a high incidence of MLL translocations. Several studies demonstrated the unique gene expression profile associated with MLL-rearranged ALL, but generally small cohorts were analyzed as uniform patient groups regardless of the type of MLL translocation, while the analysis of translocation-negative infant ALL remained unacknowledged. We generated and analyzed primary infant ALL expression profiles (n=73) typified by translocations t(4;11), t(11;19) and t(9;11), or the absence of MLL translocations, in order to study translocation-specific gene expression between the different genetic subtypes of infant ALL.
2009-12-15 | E-GEOD-19475 | biostudies-arrayexpress
Project description:Acute Lymphoblastic Leukemia (ALL) in infants (<1 year of age) is characterized by a high incidence of MLL translocations which is associated with a poor prognosis. Contributing to this poor prognosis is cellular drug resistance, especially to glucocorticoids like prednisolone. Although in vitro prednisolone resistance mechanisms have been proposed in pediatric ALL, it has never been studied in MLL-rearranged infant ALL, which are highly resistant to glucocorticoids in vitro and in vivo.
2011-10-13 | GSE32962 | GEO
Project description:Although the prognosis for childhood Acute Lymphoblastic Leukemia (ALL) in general has improved tremendously over the last decades, the survival chances for infants (<1 year of age) with ALL remains poor. A major obstacle hampering successful treatment results in infant ALL is cellular resistance to several drugs currently used in the treatment of ALL, especially to prednisolone (or prednisone). Therefore we set out to search for genes differentially expressed between from infant (children <1 year of age) and non-infant (children >1 year of age) ALL samples either resistant or sensitive to prednisolone. The in vitro prednisolone response in primary infant and non-infant ALL samples was determined by 4-day cytotoxicity (MTT) assays. Patient samples were characterized as either sensitive or resistant based on the LC50 value (i.e. the concentration of prednisolone lethal to 50% of the leukemic cells). Prednisolone sensitivity was defined by LC50 values <0.1 ug/mL prednisolone, and prednisolone resistance by LC50 values >150 ug/mL. Samples showing intermediate in vitro prednisolone responses were excluded. In total 25 infant (<1 year of age) and 27 non-infant (>1 year of age) ALL samples were selected for RNA extraction and hybridization on Affymetrix HU133A microarrays. The obtained gene expression signatures were used to identify gene differentially expressed between prednisolone resistant and sensitive patients, in order to gain insights into the mechanism(s) underlying prednisolone resistance in infant and non-infant ALL.
2009-12-15 | E-GEOD-19143 | biostudies-arrayexpress
Project description:Extensive molecular and prognostic characterization of wild-type MLL infant ALL. Background: Approximately 20% of all infant ALL cases carry wild-type (or germline) MLL genes. To date, wild-type MLL infant ALL patients are generally regarded as young pediatric precursor B-ALL patients, but extensive characterization of this specific patient group largely remains unacknowledged. Methods: We here studied a relatively large cohort of 78 wild-type MLL infant ALL samples, using clinical parameters, array-comparative genomic hybridization analysis, gene expression profiling, multiplex ligation-dependent probe amplification, and conventional sequencing. Findings: Wild-type MLL infant ALL patients are generally characterized by a lower incidence of favourable prognostic factors than pediatric (non-infant) B-ALL patients, and patients at high risk of therapy failure typically display an immature pro-B immunophenotype or respond poorly to prednisone. Using gene expression profiling, we found MEIS1 expression to additionally be highly predictive for clinical outcome in wild-type MLL infant ALL with a favourable prognosis in the wild-type MLL infants with low MEIS1 expression (DFS 88%% versus 50%, p=0•01). Overall the incidence of DNA copy number variations and genetic abnormalities in genes involved in B-cell differentiation is lower in wild-type MLL infant ALL patients as compared with pediatric precursor B-ALL patients. Interpretation: Wild-type MLL infant ALL represents a highly heterogeneous patient group, which cannot be unified by one or a few known recurrent genomic aberrations. High-level MEIS1 expression and an immature pro-B immunophenotype in high-risk wild-type MLL infant ALL patients shows parallel with the unfavourable prognosis of MLL-rearranged infant ALL patients. In contrast, wild-type MLL infant ALL patients expressing lower levels of MEIS1 and displaying more differentiated (pre-B or common) phenotypes may well be more related to pediatric precursor B-ALL patients older than 1 year of age. We advocate that a treatment strategy in wild-type MLL infant ALL based on MEIS1 expression could be beneficial for improving survival. Gene expression profiling of wild-type MLL infant ALL. Additional wild-type MLL infant ALL patient samples (n=17) to the earlier samples published under GSE19475 (GSM485309 to GSM485322).
2014-10-01 | E-GEOD-58565 | biostudies-arrayexpress
Project description:In vitro prednisolone resistance signature in MLL-rearranged infant ALL
| PRJNA146413 | ENA
Project description:B-cell acute lymphoblastic leukemia (B-ALL) is the most prevailing childhood cancer. As predicated by its prenatal origin, infant B-ALL (iB-ALL) show a silent mutational landscape irrespective of the MLL rearrangement/status, suggesting that other regulatory mechanisms might be impaired in the context of the disease. Here we used the most recent Illumina MethylationEPIC Beadchip platform to describe the genome-wide DNA methylation changes observed in a total of 69 de novo MLL-AF4+, MLL-AF9+ and non-rearranged MLL iB-ALL leukemias uniformly treated according to Interfant 99/06 protocol. Please note that samples X8 and X9 (pool of B cells and BCP) correspond to samples 200340580160_R08C01 and 200340580161_R07C01 from study E-MTAB-6315, respectively.
2021-03-12 | E-MTAB-8505 | biostudies-arrayexpress
Project description:Infant and adult MLL-rearranged (MLLr) leukemia represents a disease with few treatment options and a dismal prognosis. Here, we present an in-depth proteomic characterization of in utero-initiated and adult-onset MLLr leukemia in a mouse model of MLL-ENL-mediated leukemogenesis. We characterize early proteomic events of MLL-ENL-mediated transformation in fetal and adult progenitors.
2024-04-02 | PXD042249 | Pride
Project description:The aggressive MLL-rearranged leukemias are well-known for their unique gene-expression profiles. The goal of this study was to characterize the MLL-specific DNA methylation profiles in infant acute lymphoblastic leukemia (ALL). Genome-wide DNA methylation profiling was performed on primary infant ALL samples. The majority of infant ALL samples demonstrated severe DNA hypermethylation compared with normal pediatric bone marrows, which implies that targeting of DNA methylation may be an interesting option for future therapeutic strategies in MLL-rearranged infant ALL. Using ALL cell lines carrying the MLL translocation t(4;11) (SEMK2 and RS4;11) as a model for the patient cells, we demonstrated that the hypermethylated genes are sensitive to demethylation.
2009-11-23 | GSE18400 | GEO
Project description:We investigated the role of the transcriptional regulators Id2 and E2-2 (encoded by Tcf4) in the context of MLL-rearranged acute myeloid leukemia (AML). Using an AML mouse model driven by a Tet-off inducible MLL-AF9 allele co-expressed with oncogenic NRASG12D, we demonstrated that MLL-AF9 regulates the E protein pathway by suppressing Id2, while activating the expression of its target E2-2. Moreover, we found that Id2 over-expression in MLL-AF9 AML cells results inhibition of leukemia growth, loss of leukemia stem cell-associated gene expression pattern and induction of differentiation. E2-2 silencing phenocopies Id2 overexpression in MLL-AF9-AML cells. To study the gene expression changes associated with E2-2 depletion in the context of MLL-rearranged AML, RNA sequencing analysis was performed on MLL-AF9;NRAS AML cells transduced with vectors expressing hairpins against E2-2 (shTcf4#654 and shTcf4#3646) or a control hairpin against Renilla luciferase (shRen). Primary AMLs driven by MLL/AF9 expression linked to cherry reporter, in association with oncogenic NRASG12D (MLL/AF9;NRAS) were generated by reconstituting lethally irradiated congenic mice with fetal liver cells co-transduced with the MSCV-MLL/AF9-IRES-cherry retroviral vector and a second vector co-expressing NRASG12D together with luciferase (MSCV-luciferase-IRES-NRASG12D). RNA sequencing analysis sequencing analysis was performed on MLL-AF9;NRAS AML cells transduced in vitro with vectors expressing hairpins against E2-2 (shTcf4#654 and shTcf4#3646) or a control hairpin against Renilla luciferase (shRen) linked to the reporter GFP. Viable GFP-positive cells were FACS-sorted 2 days after transduction and used for RNA sequencing analysis. Two independent biological replicates of the experiment were used for the RNA sequencing (9-5-14 and 14-4-14).
2016-06-29 | E-GEOD-80745 | biostudies-arrayexpress
Project description:We investigated the role of the transcriptional regulator Id2 in the context of MLL-rearranged acute myeloid leukemia (AML). Using an AML mouse model driven by tet-regulated MLL-AF9 co-expressed with oncogenic NRASG12D (Tet-off MLL-AF9), we demonstrated that MLL-AF9 regulates the E protein pathway by suppressing Id2, while activating the expression of its target E2-2. Moreover, we found that Id2 over-expression in Tet-Off MLL-AF9 AML cells in vitro partially phenocopies MLL-AF9 depletion and results inhibition of leukemia growth, loss of leukemia stem cell-associated gene expression pattern and induction of differentiation. To compare gene expression changes associated with enforced Id2 expression and MLL-AF9 withdrawal, RNA sequencing analysis was performed on Tet-off MLL-AF9 cells transduced with an Id2 over-expressing or a control vector, or upon MLL-AF9 dox-inducible knock-down. Primary AMLs driven by Tet-off inducible MLL/AF9 expression linked to dsRED reporter, in association with oncogenic NRASG12D (Tet-off MLL-AF9) were generated by reconstituting lethally irradiated congenic mice with foetal liver cells co-transduced with a Tet-Off-MLL-AF9-dRED retroviral vector and a second vector co-expressing NRASG12D together with the Tet-Off responsive transcriptional activator. RNA sequencing analysis sequencing analysis was performed on Tet-Off MLL-AF9/dsRED+ AML cells treated in vitro with doxycycline (DOX) for 4 days to inactivate MLL-AF9 expression or left untreated (UT). For the Id2 over-expression experiment, Tet-Off MLL-AF9/dsRED+ AML cells were transduced in vitro with an Id2-GFP or a control-GFP retroviral vector. Viable GFP-positive cells were FACS-sorted 2 days after transduction and used for RNA sequencing analysis.
2016-06-29 | E-GEOD-68462 | biostudies-arrayexpress