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GSE11794
Mus musculus
64 Downloadable Samples
Affymetrix Murine Genome U74A Version 2 Array (mgu74av2)
Description
Oncogenic tyrosine kinases, such as BCR-ABL, TEL-ABL, TEL-PDGF-beta-R and FLT3-ITD, play a major role in the development of hematopoietic malignancy. They activate many of the same signal transduction pathways.
Publication Title
Id1 is a common downstream target of oncogenic tyrosine kinases in leukemic cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Prospective identification of resistance mechanisms to HSP90 inhibition in KRAS mutant cancer cells.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Inhibition of the HSP90 chaperone results in depletion of many signaling proteins that drive tumorigenesis, such as downstream effectors of KRAS, the most commonly mutated human oncogene. As a consequence, several small-molecule HSP90 inhibitors are being evaluated in clinical trials as anticancer agents. To prospectively identify mechanisms through which HSP90-dependent cancer cells evade pharmacologic HSP90 blockade, we generated multiple mutant KRAS-driven cancer cell lines with acquired resistance to the purine-scaffold HSP90 inhibitor PU-H71. All cell lines retained dependence on HSP90 function, as evidenced by sensitivity to short hairpin RNA-mediated suppression of HSP90AA1 or HSP90AB1 (also called HSP90 and HSP90, respectively), and exhibited two types of genomic alterations that interfere with the effects of PU-H71 on cell viability and proliferation: (i) a Y142N missense mutation in the ATP-binding domain of HSP90 that co-occurred with amplification of the HSP90AA1 locus, (ii) genomic amplification and overexpression of the ABCB1 gene encoding the MDR1 drug efflux pump. In support of a functional role for these alterations, exogenous expression of HSP90 Y142N conferred PU-H71 resistance to HSP90-dependent cells, and pharmacologic MDR1 inhibition with tariquidar or lowering ABCB1 expression restored sensitivity to PU-H71 in ABCB1-amplified cells. Finally, comparison with structurally distinct HSP90 inhibitors currently in clinical development revealed that PU-H71 resistance could be overcome, in part, by ganetespib (also known as STA9090) but not tanespimycin (also known as 17-AAG). Together, these data identify potential mechanisms of acquired resistance to small molecules targeting HSP90 that may warrant proactive screening for additional HSP90 inhibitors or rational combination therapies.
Publication Title
Prospective identification of resistance mechanisms to HSP90 inhibition in KRAS mutant cancer cells.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Recently, the p53-miR-34a network was identified to play an important role in tumorigenesis. As in acute myeloid leukemia with complex karyotype (CK-AML) TP53 alterations are the most common known molecular lesion, we further analyzed the p53-miR-34a axis in CK-AML with known TP53 status. Clinically, low miR-34a expression and TP53 alterations predicted for chemotherapy resistance and inferior outcome. Notably, in TP53unaltered CK-AML high miR-34a expression predicted for inferior overall survival (OS), whereas in TP53biallelic altered CK-AML high miR-34a expression pointed to better OS.
Publication Title
Altered miRNA and gene expression in acute myeloid leukemia with complex karyotype identify networks of prognostic relevance.
Sample Metadata Fields
Disease
View Samples- Mus musculus
- 10 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Aberrant expression of the homeodomain transcription factor CDX2 occurs in most cases of acute myeloid leukemia (AML) and promotes leukemogenesis, making CDX2, in principle, an attractive therapeutic target. Conversely, CDX2 acts as a tumor suppressor in colonic epithelium. The effectors mediating the leukemogenic activity of CDX2 and the mechanism underlying its context-dependent properties are poorly characterized, and strategies for interfering with CDX2 function in AML remain elusive. We report data implicating repression of the transcription factor KLF4 as important for the oncogenic activity of CDX2, and demonstrate that CDX2 differentially regulates KLF4 in AML versus colon cancer cells through a mechanism that involves tissue-specific patterns of promoter binding and epigenetic modifications. Furthermore, we identified deregulation of the PPAR signaling pathway as a feature of AML expressing CDX2, and observed that PPAR agonists derepress KLF4 and are preferentially toxic to CDX2-positive leukemic cells. These data delineate transcriptional programs associated with CDX2 expression in hematopoietic cells; provide insight into the antagonistic duality of CDX2 function in AML versus colon cancer; and suggest reactivation of KLF4 expression, through modulation of PPAR signaling, as a new therapeutic modality in a large proportion of AML patients.
Publication Title
CDX2-driven leukemogenesis involves KLF4 repression and deregulated PPARγ signaling.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 253 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Many cases of acute myeloid leukemia (AML) are associated with mutational activation of RTKs such as FLT3. However, RTK inhibitors have limited clinical efficacy as single agents, indicating that AML is driven by concomitant activation of different signaling molecules. We used a functional genomic approach to identify RET, encoding an RTK not previously implicated in AML, as essential gene in different AML subtypes, and observed that RET-dependent AML cells show activation of RET signaling via ARTN/GFRA3 and NRTN/GFRA2 ligand/co-receptor complexes.
Publication Title
RET-mediated autophagy suppression as targetable co-dependence in acute myeloid leukemia.
Sample Metadata Fields
Specimen part, Disease
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Many human oncogenes are challenging therapeutic targets. An alternative to direct targeting of oncogenes is to perform synthetic lethality screens for genes that are essential only in the context of specific cancer-causing mutations. We used high-throughput RNA interference (RNAi) to identify synthetic lethal interactions in cancer cells harboring mutant KRAS, the most commonly mutated human oncogene. We find that cells that are dependent on mutant KRAS exhibit sensitivity to suppression of the serine/threonine kinase STK33 irrespective of tissue origin, whereas STK33 is not required by KRAS-independent cells. STK33 promotes cancer cell viability in a kinase activity-dependent manner by regulating the suppression of mitochondrial apoptosis mediated through S6K1-induced inactivation of the death agonist BAD selectively in mutant KRAS-dependent cells. These observations identify STK33 as a target for treatment of the broad spectrum of mutant KRAS-driven cancers, and demonstrate the potential of RNAi screens for discovering critical functional dependencies created by oncogenic mutations that may enable therapeutic intervention for cancers associated with undruggable genetic alterations.
Publication Title
Synthetic lethal interaction between oncogenic KRAS dependency and STK33 suppression in human cancer cells.
Sample Metadata Fields
Cell line
View Samples- Escherichia coli str. k-12 substr. mg1655
- 58 Downloadable Samples
- Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
The widespread use of electricity raises the question of whether or not 50 Hz (power line frequency in Europe) magnetic fields (MFs) affect organisms. We investigated the transcription of Escherichia coli K-12 MG1655 in response to extremely low-frequency (ELF) MFs. Fields generated by three signal types (sinusoidal continuous, sinusoidal intermittent, and power line intermittent; all at 50 Hz, 1 mT), were applied and gene expression was monitored at the transcript level using an Affymetrix whole-genome microarray. Bacterial cells were grown continuously in a chemostat (dilution rate D = 0.4 h-1) fed with glucose-limited minimal medium and exposed to 50 Hz MFs with a homogenous flux density of 1 mT. For all three types of MFs investigated, neither bacterial growth (determined using optical density) nor culturable counts were affected. Likewise, no statistically significant change (fold-change > 2, P 0.01) in the expression of 4,358 genes and 714 intergenic regions represented on the gene chip was detected after MF exposure for 2.5 h (1.4 generations) or 15 h (8.7 generations). Moreover, short-term exposure (8 min) to the sinusoidal continuous and power line intermittent signal neither affected bacterial growth nor showed evidence for reliable changes in transcription. In conclusion, our experiments did not indicate that the different tested MFs (50 Hz, 1 mT) affected the transcription of E. coli.
Publication Title
Genome-wide transcription analysis of Escherichia coli in response to extremely low-frequency magnetic fields.
Sample Metadata Fields
Treatment
View Samples- Mus musculus, Homo sapiens
- 8 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Musashi-2 regulates normal hematopoiesis and promotes aggressive myeloid leukemia.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Mus musculus
- 3 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
We demonstrate that Msi2 is the predominant form expressed in hematopoietic stem cells (HSC), and its knockdown leads to reduced engraftment and depletion of HSCs in vivo. Overexpression of Msi2 in a mouse model increases HSC cell cycle progression and cooperates with BCR-ABL1 to induce an aggressive leukemia. MSI2 is over-expressed in human myeloid leukemia, and expression levels directly correlate with decreased patient survival, thereby defining MSI2 expression as a novel prognostic marker in acute myeloid leukemia (AML). Depletion of MSI2 in human myeloid leukemia cells leads to decreased proliferation and apoptosis. These data implicate the MSI2 RNA binding protein in myeloid leukemogenesis and identify a novel potential target for therapy in AML.
Publication Title
Musashi-2 regulates normal hematopoiesis and promotes aggressive myeloid leukemia.
Sample Metadata Fields
Specimen part
View Samples