Imatinib has become the current standard therapy for patients with chronic myelogenous leukaemia (CML). For a better understanding of the Imatinib-related molecular effects in vivo, we assessed gene expression profiles of Philadelphia Chromosome positive (Ph+) CD34+ cells from peripheral blood of 6 patients with de novo CML in chronic phase. After 7 days of treatment with Imatinib the Ph+ CD34+ cells were reassessed to look for changes in the transcriptome. The expression level of 303 genes was significantly different comparing the transcriptome of the Ph+ CD34+ cells before and after 7 days of Imatinib therapy (183 down-regulated, 120 up-regulated, lower bound 1.2-fold). For a substantial number of genes governing cell cycle and DNA replication, the level of expression significantly decreased (CDC2, RRM2, PCNA, MCM4). On the other hand, therapy with Imatinib was associated with an increase of genes related to adhesive interactions, such as L-selectin or CD44. A group of 8 genes with differential expression levels were confirmed using a gene specific quantitative real-time PCR. Thus, during the first week of treatment, Imatinib is preferentially counteracting the bcr-abl induced effects related to a disturbed cell cycle and defective adhesion of leukemic Ph+ CD34+ cells.
Early in vivo changes of the transcriptome in Philadelphia chromosome-positive CD34+ cells from patients with chronic myelogenous leukaemia following imatinib therapy.
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View SamplesWe found that composition of cell subsets within the CD34+ cell population is markedly altered in chronic phase (CP) chronic myeloid leukemia (CML). Specifically, proportions and absolute cell counts of common myeloid progenitors (CMP) and megakaryocyte-erythrocyte progenitors (MEP) are significantly greater in comparison to normal bone marrow whereas absolute numbers of hematopoietic stem cells (HSC) are equal. To understand the basis for this, we performed gene expression profiling (Affymetrix HU-133A 2.0) of the distinct CD34+ cell subsets from six patients with CP CML and five healthy donors. Euclidean distance analysis revealed a remarkable transcriptional similarity between the CML patients' HSC and normal progenitors, especially CMP. CP CML HSC were transcriptionally more similar to their progeny than normal HSC to theirs, suggesting a more mature phenotype. Hence, the greatest differences between CP CML patients and normal donors were apparent in HSC including downregulation of genes encoding adhesion molecules, transcription factors, regulators of stem-cell fate and inhibitors of cell proliferation in CP CML. Impaired adhesive and migratory capacities were functionally corroborated by fibronectin detachment analysis and transwell assays, respectively. Based on our findings we propose a loss of quiescence of the CML HSC on detachment from the niche leading to expansion of myeloid progenitors.
The hematopoietic stem cell in chronic phase CML is characterized by a transcriptional profile resembling normal myeloid progenitor cells and reflecting loss of quiescence.
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View SamplesMature NK and T-cell lymphomas are occasionally encountered in Asia but are very rare in Western populations. In part due to its rarity, little is known about this group of neoplasms, and despite being rather different disease entities, they are all treated similarly but with diverse clinical outcomes. Novel biomarkers (at both the genetic and protein levels) are needed to resolve diagnostic difficulties, improve prognostication and develop targeted therapies. To rectify this deficiency, we interrogated the transcriptome of several NK and mature T-cell lymphomas by whole-genome expression profiling for new markers that may further stratify this diverse group of conditions. Our initial efforts have identified a promising candidate marker that appears to differentiate NKTL lymphoma from other forms of T-cell neoplasms, and this finding has been validated by immunohistochemistry on archival material in a large number of patient cases.
Nuclear expression of MATK is a novel marker of type II enteropathy-associated T-cell lymphoma.
Specimen part, Cell line
View SamplesEndocrine therapy is the main therapeutic option for patients with estrogen receptor alpha positive (ER+) breast cancer. Nevertheless, most of them become estrogen-independent and relapse after the treatment. Ret is a tyrosine kinase receptor that shows elevated expression levels in ER+ human breast tumors. In this study, we demonstrate that activation of the Ret receptor promotes proliferation as well as cell migration irrespective of endocrine therapy. Microarray data show that Ret activation involves changes in the expression of inflammatory- and motility-related genes. In vivo treatment with a Ret pathway inhibitor in a ER+/Ret+ mouse mammary cancer model, reduces tumor growth and lung metastasis even after endocrine therapy. Additionally, we show a connection between Ret and inflammatory pathways. The pro-inflamatory cytokine IL6 lies at the core of this regulation, which involves a positive feedback loop with IL6 and the Ret pathway reciprocally stimulating each other to further leading metastasis risk. Our findings provide insight into endocrine resistance mechanism and point at the Ret pathway as a potential target for future therapies.
Ret inhibition decreases growth and metastatic potential of estrogen receptor positive breast cancer cells.
Cell line, Treatment, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
High expression of miR-125b-2 and SNORD116 noncoding RNA clusters characterize ERG-related B cell precursor acute lymphoblastic leukemia.
Specimen part, Disease, Disease stage
View SamplesERG-related B cell precursor acute lymphoblastic leukemia (BCP ALL) is a recently described childhood ALL subtype characterized by aberrant ERG protein expression and highly recurrent ERG intragenic deletions. Several studies reported a remarkably favourable outcome for ERG-related BCP-ALL despite a high incidence of apparently inauspicious IKZF1 aberrations. In this study we investigated by integrative genomic analysis the main features of the ERG-related group in a cohort of B-others BCP ALL patients enrolled in the AIEOP ALL 2000 therapeutic protocol. We report a specific microRNA and snoRNA signature that characterizes ERG-related patients with up-regulation of the miR-125b-2 cluster on chromosome 21 and several snoRNAs in the Prader-Willi locus at 15q11.2, including the orphan SNORD116 cluster. Given the current lack of parameters for a comprehensive classification we suggest toexploit the noncoding RNAs signature for differential diagnosis of ERG-related patients.
High expression of miR-125b-2 and SNORD116 noncoding RNA clusters characterize ERG-related B cell precursor acute lymphoblastic leukemia.
Specimen part, Disease, Disease stage
View SamplesThe ecto-enzyme CD38 is a marker of unfavorable prognosis for chronic lymphocytic leukemia (CLL) patients and an indicator of activation and proliferation of leukemic cells. Here we show that CD38 is enzymatically active in primary CLL cells and that its forced expression increases disease aggressiveness in a xenograft model. The effect is completely lost when using an enzyme deficient version of CD38 with a single amino-acid mutation. Through the enzymatic conversion of NAD, CD38 increases cytoplasmic Ca2+ concentrations, positively influencing proliferation, chemotaxis, adhesion and matrix digestion. Inhibition of the enzymatic activities of CD38 using the flavonoid kuromanin blocks CLL homing. In a short-term xenograft model using primary cells, kuromanin treatment traps CLL cells in the blood, increasing responses to chemotherapy.
The enzymatic activities of CD38 enhance CLL growth and trafficking: implications for therapeutic targeting.
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View SamplesClonal cellular variance often confounds reproducibility of forward and reverse genetic studies. We developed combinatorial approaches for whole genome saturated mutagenesis using haploid murine ES cells to permit induction and reversion of genetic mutations. Using these systems, we created a biobank with over 100000 individual ES cell lines with repairable and genetically bar coded mutations targeting 16950 genes. This biobank termed “Haplobank” is freely available. In addition, we developed a genetic color coding system for rapid repair of mutations and direct functional validation in sister clones. Using this system, we report functional validation of essential ES cell genes. We also identified phospholipase16G as a key pathway for cytotoxicity of human rhinoviruses, the most frequent cause of the common cold. Moreover, we derived 3D blood vessel organoids from haploid ES cells, combining conditional mutagenesis in haploid ES cells with tissue engineering. We identified multiple novel genes, such as Connexin43/Gja1, in blood vessel formation and tip cell specification in vitro and also in vivo. Taken together, we develop a conditional homozygous ES cell resource for the community to empower controlled genetic studies in murine ES cells and tissues derived from it. Overall design: RNA-Seq was carried out using standard protocols. https://www.haplobank.at/ecommerce/control/haplobank_resource
Comparative glycoproteomics of stem cells identifies new players in ricin toxicity.
Subject
View SamplesDiagnostic samples of peripheral blood form acute myeloid leukemia were analysed for gene expression differences
NFATc1 as a therapeutic target in FLT3-ITD-positive AML.
Sex, Specimen part
View SamplesGenetic variation governs protein expression through both transcriptional and post-transcriptional processes. To investigate this relationship, we combined a multiplexed, mass spectrometry-based method for protein quantification with an emerging mouse model harboring extensive genetic variation from 8 founder strains. We collected genome-wide mRNA and protein profiling measurements to link genetic variation to protein expression differences in livers from 192 Diversity Outcross mice. Overall design: Illumina 100bp single-end liver RNA-seq from 192 male and female Diversity Outbred 26-week old mice raised on standard chow or high fat diet. Each sample was sequenced in 2x technical replicates across multiple flowcells. Samples were randomly assigned lanes and multiplexed at 12-24x.
Epistatic Networks Jointly Influence Phenotypes Related to Metabolic Disease and Gene Expression in Diversity Outbred Mice.
Sex, Specimen part, Cell line, Subject
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