Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Deregulated apoptosis signaling in core binding factor leukemia differentiates clinically relevant, molecular marker independent subgroups

ABSTRACT: Core binding factor (CBF) leukemias, characterized by translocations t(8;21) or inv(16)/t(16;16) targeting the core binding factor, constitute acute myeloid leukemia (AML) subgroups with favorable prognosis. However, about 40% of patients relapse, and the current classification system does not fully reflect this clinical heterogeneity. Previously, gene expression profiling (GEP) revealed two distinct CBF leukemia subgroups displaying significant outcome differences and identified apoptotic signaling, MAPKinase signaling and chemotherapy-resistance mechanisms among the most significant differentially regulated pathways. We now tested different inhibitors of the respective pathways in a cell line model (six cell lines reflecting the CBF subgroup specific gene expression alterations), and found apoptotic signaling to be differentiating between the CBF subgroup models. In accordance, primary samples from newly diagnosed CBF AML patients (n=23) also showed differential sensitivity to in vitro treatment with a Smac mimetic such as BV6, an antagonist of inhibitor of apoptosis (IAP) proteins , and ABT-737, a BCL2 inhibitor. Furthermore, GEP revealed the BV6 resistant cases to resemble the previously identified unfavorable CBF subgroup. Thus, our current findings show deregulated IAP expression and apoptotic signaling to differentiate clinically relevant CBF subgroups, which were independent of known molecular markers, thereby providing a starting point for novel therapeutic approaches.

ORGANISM(S): Homo sapiens

PROVIDER: GSE29883 | GEO | 2011/06/11

SECONDARY ACCESSION(S): PRJNA140737

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Deregulated apoptosis signaling in core binding factor leukemia differentiates clinically relevant, molecular marker independent subgroups

Project description:Core binding factor (CBF) leukemias, characterized by translocations t(8;21) or inv(16)/t(16;16) targeting the core binding factor, constitute acute myeloid leukemia (AML) subgroups with favorable prognosis. However, about 40% of patients relapse, and the current classification system does not fully reflect this clinical heterogeneity. Previously, gene expression profiling (GEP) revealed two distinct CBF leukemia subgroups displaying significant outcome differences and identified apoptotic signaling, MAPKinase signaling and chemotherapy-resistance mechanisms among the most significant differentially regulated pathways. We now tested different inhibitors of the respective pathways in a cell line model (six cell lines reflecting the CBF subgroup specific gene expression alterations), and found apoptotic signaling to be differentiating between the CBF subgroup models. In accordance, primary samples from newly diagnosed CBF AML patients (n=23) also showed differential sensitivity to in vitro treatment with a Smac mimetic such as BV6, an antagonist of inhibitor of apoptosis (IAP) proteins , and ABT-737, a BCL2 inhibitor. Furthermore, GEP revealed the BV6 resistant cases to resemble the previously identified unfavorable CBF subgroup. Thus, our current findings show deregulated IAP expression and apoptotic signaling to differentiate clinically relevant CBF subgroups, which were independent of known molecular markers, thereby providing a starting point for novel therapeutic approaches. All samples were obtained from untreated patients at the time of diagnosis. Cells used for microarray analysis were collected from the purified fraction of mononuclear cells after Ficoll density centrifugation. Routine diagnostic algorithms, including the characterization of molecular markers are performed.

2011-06-11 | E-GEOD-29883 | biostudies-arrayexpress

Transcription profiling of human core binding factor acute myeloid leukemias to identify molecular subclasses within the group

Project description:Core binding factor (CBF) leukemias, characterized by either inv(16)/t(16;16) or t(8;21), constitute acute myeloid leukemia (AML) subgroups with favorable prognosis. However, there exists substantial biological and clinical heterogeneity within these cytogenetic groups, which is not fully reflected by the current classification system. To improve the molecular characterization we profiled gene expression in a large series (n=93) of AML patients with CBF leukemia [inv(16) n=55, t(8;21) n=38]. By unsupervised hierarchical clustering we were able to define a subgroup of CBF cases (n=35) characterized by shorter overall survival times (P=0.03). While there was no obvious correlation with fusion gene transcript levels, FLT3 tyrosine kinase domain, KIT, and NRAS mutations, the newly defined inv(16)/t(8;21)-subgroup was associated with elevated white blood cell counts and FLT3 internal tandem duplications (P=0.011 and P=0.026, respectively). Supervised analyses of gene expression suggested alternative cooperating pathways leading to transformation. In the ?favorable? CBF leukemias anti-apoptotic mechanisms and deregulated mTOR-signaling, and in the newly defined ?unfavorable? subgroup aberrant MAPKinase-signaling and chemotherapy-resistance mechanisms might play a role. While the leukemogenic relevance of these signatures remains to be validated, their existence nevertheless supports a prognostically relevant biological basis for the heterogeneity observed in CBF leukemia.

2007-06-10 | E-SMDB-4056 | biostudies-arrayexpress

Gene expression profiling identifies distinct subclasses of core binding factor acute myeloid leukemia.

2007-08-09 | E-GEOD-8653 | biostudies-arrayexpress

Gene expression profiling identifies distinct subclasses of core binding factor acute myeloid leukemia.

2007-08-09 | GSE8653 | GEO

Inhibitor of apoptosis protein antagonist BV6 – potential for new combinatorial treatment strategies in acute myeloid leukemia

Project description:Apoptosis is deregulated in most, if not all, cancers, including hematological malignancies. In this study, we wanted to test whether primary acute myeloid leukemia (AML) samples are sensitive for inhibitor of apoptosis (IAP) protein antagonist treatment in vitro, and which AML subgroup might profit most from such a novel therapeutic strategy. We treated diagnostic samples of 67 adult AML patients with either cytarabine (ara-C) or IAP antagonist BV6 and correlated sensitivity with clinical, cytogenetic and molecular markers, and expression levels of selected genes involved in apoptosis. Primary AML samples showed differential sensitivity to treatment with either ara-C (40% sensitive, 17% intermediate, 43% resistant) or BV6 (51% sensitive, 21% intermediate, 28% resistant). Notably, 69% of ara-C resistant samples showed a good to fair response to IAP inhibition. Furthermore, combination treatment of ara-C with BV6 showed additive effects in most samples. Differences in sensitivity to IAP antagonist treatment correlated with significantly elevated expression levels of TNF and lower levels of XIAP in BV6 sensitive samples, as well as with NPM1 mutations. Gene expression profiling pointed to apoptosis-related pathways, which were specifically induced by IAP inhibition in sensitive samples. Thus, our results suggest IAP inhibition as a potential novel therapeutic option in AML.

2014-12-31 | GSE46819 | GEO

Inhibitor of apoptosis proteins as promising therapeutic targets in chronic lymphocytic leukemia

Project description:Inhibitor of apoptosis (IAP) proteins are expressed at high levels in CLL cells and may contribute to evasion of cell death leading to poor therapeutic outcome. Of note, prognostic unfavourable cases with e.g. non-mutated VH-status and TP53 mutation responded significantly better to BV6 than samples with unknown or favourable prognosis e.g. 13q deletion. The majority of cases with 17p deletion (10/12) and Fludarabine refractory cases were sensitive to BV6, indicating that BV6 acts independently of the p53 pathway. Importantly, BV6 dose-dependently induced cell death in 28 of 51 (54%) investigated patient samples while B cells from healthy donors were largely unaffected. BV6 also triggered cell death under survival conditions mimicking the microenvironment e.g. by adding CD40 ligand or in conditioned medium. Gene expression profiling identified cell death- and NF-kB-signaling among the top pathways regulated by BV6. This was confirmed by data showing that BV6 causes degradation of cIAP1 and cIAP2 and NF-kB pathway activation. BV6 induced cell death depended on production of reactive oxygen species, since addition of ROS scavengers significantly rescued BV6-triggerd cell death. In contrast, BV6 induced cell death independently of caspase activity, RIP1 activity or TNF-alpha, since zVAD.fmk, necrostatin-1 or TNF-alpha-blocking antibody Enbrel failed to protect against cell death. Of note, transcripts of ROS regulatory proteins were modulated by BV6. Thus, these data have important implications for developing new therapeutic strategies to overcome cell death resistance in CLL especially in poor prognostic subgroups. Gene expression was profiled in 12 CLL samples [n=3 CLL cases for 4 hours and 20 hours with either DMSO or BV6].

2015-03-31 | E-GEOD-62533 | biostudies-arrayexpress

Inhibitor of apoptosis proteins as promising therapeutic targets in chronic lymphocytic leukemia

2015-03-31 | GSE62533 | GEO

Gene expression profiles of mono- and biallelic CEBPA mutations in cytogenetically normal AML

Project description:Purpose: CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal AML (CN-AML). Patients and Methods: 467 homogeneously treated CN-AML patients were subdivided into moCEBPA, biCEBPA and wildtype (wt) CEBPA patients. The subgroups were analyzed for clinical parameters and for additional mutations in the NPM1, FLT3 and MLL genes. Furthermore, we obtained gene expression profiles (GEP) for a subgroup of 61 patients using oligonucleotide microarrays.

2009-12-31 | GSE15210 | GEO

Transcription profiling of human AML FAB-M0 samples

Project description:Ficolled AML-M0 sample gene expression profiles on Affymetrix HGU133Plus2.0 GeneChips. Acute myeloid leukemia (AML) classified as FAB-M0 is defined as a subtype with minimally differentiated morphology. Here we investigated by gene expression (GEP) profiling whether AML-M0 cases should be considered as one or more unique molecular subgroups that discriminates them from other AML patients. By applying GEP and subsequent unsupervised analysis of 35 AML-M0 samples and 253 previously reported AML cases, we demonstrate that AML-M0 cases express a unique signature. Hematological transcription regulators such as CEBPA, CEBPD, PU.1 and ETV6 and the differentiation associated gene MPO appeared strongly down-regulated, in line with the very primitive state of this type of leukemia. Moreover, AML M0 cases appeared to have a strong positive correlation with a previously defined immature AML subgroup with adverse prognosis. AML-M0 leukemias frequently carry loss-of-function RUNX-1 mutation and unsupervised analyses revealed a striking distinction between cases with and without mutations. RUNX1 mutant AML-M0 samples showed a distinct up-regulation of B-cell-related genes, e.g. members of the B-cell receptor complex, transcriptions regulators RUNX3, ETS2, IRF8 or PRDM1 and major histocompatibility complex class II genes. Importantly, expression of one single gene, i.e. BLNK, enabled prediction of RUNX1 mutations in AML-M0 with high accuracy. We propose that RUNX1 mutations in this subgroup of AML cause lineage infidelity, leading to aberrant co-expression of myeloid and B-lymphoid genes in the same cells. Experiment Overall Design: 35 samples

2009-07-18 | E-GEOD-17061 | biostudies-arrayexpress

Gene expression profiling of 35 AML FAB-M0 samples

2009-07-14 | GSE17061 | GEO