Gene regulatory networks that govern hematopoietic stem cells (HSC) and leukemiainitiating cells (L-IC) are deeply entangled. Thus, the discovery of compounds that target L-IC while sparing HSC is an attractive but difficult endeavor. Presently, most drug discovery approaches fail to counter-screen compounds against normal hematopoietic stem/progenitor cells (HSPC) to assess therapeutic index. Here, we present a combined in vitro and in vivo strategy to identify compounds specific to L-IC in acute myeloid leukemia (AML). A high-throughput screen of 4000 compounds on novel leukemia cell lines derived from human experimental leukemogenesis models yielded 80 hits, of which most were toxic to normal HSPC. Of the 10 compounds that passed this initial filter, we chose to characterize a single compound, kinetic riboside (KR), on AML L-IC and HSPC. KR demonstrated comparable efficacy to standard therapies against 63 primary AMLs. In vitro, KR effectively targeted the L-IC-enriched CD34+CD38- AML fraction, while sparing normal HSPC enriched fractions, although these effects were mitigated on HSC assayed in vivo, and highlights the importance of in vivo L-IC and HSC assays to measure function. Overall, we provide a novel approach to screen large drug libraries for the discovery of anti-L-IC compounds for human leukemias.
A small molecule screening strategy with validation on human leukemia stem cells uncovers the therapeutic efficacy of kinetin riboside.
Cell line, Treatment
View SamplesWe analysed the transcriptome of different HSC-enriched subpopulations of cells sorted from human umbilical cord blood and isolated from several individuals with different genetic backgrounds. We aim at identifying new cell surface markers associated with human HSC and downstream mature hematopoietic cell activity. Overall design: RNA-seq of CD34+CD45RA- cord blood cells from 17 non-pooled individuals.
GPR56 identifies primary human acute myeloid leukemia cells with high repopulating potential in vivo.
Specimen part, Subject
View SamplesThe goal of the study was to identify genes that are directly or indirectly coregulated by the AhR pathway in primary human AML cells. Patient AML cells were treated for 16 hours with the two indirubin derivatives 6-bromoindirubin-3''oxime (BIO), 1-Methyl-6-bromoindirubin-3''oxime (MeBIO), the AHR-antagonist SR1 (StemReginin1), combinations of BIO+SR1 and MeBIO+SR1 or DMSO alone at indicated concentrations prior to RNA extraction for sequencing. Overall design: RNA-Seq performed on 5 primary AML samples fresh (t0) and after exposure to AhR-agonists (2), -antagonist (1), and DMSO Contributor: Leucegene Project, IRIC
GPR56 identifies primary human acute myeloid leukemia cells with high repopulating potential in vivo.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Stem cell gene expression programs influence clinical outcome in human leukemia.
Specimen part
View SamplesExperiments using xenografts show that some solid tumours and leukemias are organized as cellular hierarchies sustained by cancer stem cells (CSC). Despite promise, the relevance of the CSC model to human disease remains uncertain. Here we show that acute myeloid leukemia (AML) follows a CSC model based on sorting multiple populations from each of 16 primary human AML samples and identifying which contain leukemia stem cells (LSC) using a sensitive xenograft assay. Analysis of gene expression from all functionally validated populations yielded an LSC-specific signature. Similarly, a hematopoietic stem cell (HSC) gene signature was established. Bioinformatic analysis identified a core transcriptional program shared by LSC and HSC, revealing the molecular machinery underlying stemness properties. Both stem cell programs were highly significant independent predictors of patient survival and also found in existing prognostic signatures. Thus, determinants of stemness influence clinical outcome of AML establishing that LSC are clinically relevant and not mere artifacts of xenotransplantation.
Stem cell gene expression programs influence clinical outcome in human leukemia.
No sample metadata fields
View SamplesExperiments using xenografts show that some solid tumours and leukemias are organized as cellular hierarchies sustained by cancer stem cells (CSC). Despite promise, the relevance of the CSC model to human disease remains uncertain. Here we show that acute myeloid leukemia (AML) follows a CSC model based on sorting multiple populations from each of 16 primary human AML samples and identifying which contain leukemia stem cells (LSC) using a sensitive xenograft assay. Analysis of gene expression from all functionally validated populations yielded an LSC-specific signature. Similarly, a hematopoietic stem cell (HSC) gene signature was established. Bioinformatic analysis identified a core transcriptional program shared by LSC and HSC, revealing the molecular machinery underlying stemness properties. Both stem cell programs were highly significant independent predictors of patient survival and also found in existing prognostic signatures. Thus, determinants of stemness influence clinical outcome of AML establishing that LSC are clinically relevant and not mere artifacts of xenotransplantation.
Stem cell gene expression programs influence clinical outcome in human leukemia.
Specimen part
View SamplesCord blood stem cells were expanded and differentiated to NK cells. Samples taken at different days after induction of differentiation were analyzed and compared to undifferentiated expanded stem cells. The most highly upregulated genes were further analyzed.
The Transcription Factor ZNF683/HOBIT Regulates Human NK-Cell Development.
Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
miR-126 Regulates Distinct Self-Renewal Outcomes in Normal and Malignant Hematopoietic Stem Cells.
Specimen part, Cell line, Treatment
View SamplesIn acute myeloid leukemia (AML), leukemia stem cells (LSCs) play a central role in disease progression and recurrence due to their intrinsic capacity for self-renewal and chemotherapy resistance. Whereas epigenetic regulation balances normal blood stem cell self-renewal and fate decisions, mutation and dysregulation of epigenetic modifiers are now considered fundamental to leukemia initiation and progression. Alterations in miRNA function represent a non-canonical epigenetic mechanism influencing malignant hematopoiesis; however, the function of miRNA in LSC remains undetermined. Here we show that miRNA profiling of fractionated AML populations defines an LSC-specific signature that is highly predictive of patient survival. Gain-of-function genetic analysis demonstrated that miR-126 restrained cell cycle progression, prevented LSC differentiation, and increased LSC self-renewal. miR-126 promoted chemo-resistance, preserving LSC quiescence in part through suppression of the G0-to-G1 gatekeeper, CDK3. Thus, in AML, miRNAs influence patient outcome through post-transcriptional regulation of stemness programs in LSC.
miR-126 Regulates Distinct Self-Renewal Outcomes in Normal and Malignant Hematopoietic Stem Cells.
Specimen part, Cell line, Treatment
View SamplesCancer tissue-like structures were developed by using established human tumor cell lines in perfusion-based bioreactor systems. In colorectal cancer (CRC) cell lines, perfusion allowed more homogeneous scaffold seeding than tri-dimensional (3D) static cultures and significantly (13.7 fold, p<0.0001) higher proliferation. Resulting tissues exhibited morphology and phenotypes similar to xenografts generated in immunodeficient mice. Whole transcriptome analysis of 2D, 3D static and 3D perfusion cultures revealed the highest correlation between xenografts and 3D perfusion cultures (r=0.985). Clinically relevant concentrations of 5-FU, used in neo- and adjuvant CRC treatment, had no effect on numbers of HT-29 CRC cells cultured in 3D perfusion or xenografts, as compared with a 55.8% reduction in 2D cultures. Treatment induced apoptosis in 2D cultures, but only “nucleolar stress” in perfused cells and xenografts, consistent with partial responsiveness. In 3D perfusion cultures BCL-2, TRAF1, and FLIP gene expression was marginally affected, as compared with significant down-regulation in 2D cell cultures. Accordingly, ABT-199 BCL-2 inhibitor, induced cytostatic effects in 3D perfusion but not in 2D cell cultures (p=0.003). Tumor cells from partially responsive (Dworak 2) patients undergoing neo-adjuvant treatment, typically (10/11) expressed BCL-2, as compared with 0/3 highly (Dworak 3-4) responsive and 4/15 fully resistant CRC (Dworak 0/1, p=0.03), closely matching 3D perfusion cultures data. These results indicate that 3D perfusion cultures efficiently mimic phenotypic and functional features observed in xenografts and clinical specimens. These models may be of critical translational relevance to address fundamental human tumor cell biology issues and to develop predictive pre-clinical tests of novel compounds. Overall design: Expression profiles of colorectal cancer cell lines cultured in 2D, 3D static, 3D perfusion or growing as xenografts were generated by deep sequencing, in triplicates, using Illumina HiSeq2000.
Bioreactor-engineered cancer tissue-like structures mimic phenotypes, gene expression profiles and drug resistance patterns observed "in vivo".
No sample metadata fields
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