This SuperSeries is composed of the SubSeries listed below.
Cancer stemness in Wnt-driven mammary tumorigenesis.
No sample metadata fields
View SamplesFicolled 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.
Gene expression profiling of minimally differentiated acute myeloid leukemia: M0 is a distinct entity subdivided by RUNX1 mutation status.
Specimen part
View SamplesThe Wnt/beta-catenin signalling pathway plays a central role in mammary stem cell homeostasis and in breast cancer. We employed the CD29hiCD24+ cell surface antigens to identify a subpopulation of mammary CSCs from Apc1572T/+, a mouse model for metaplastic breast adenocarcinoma, a subtype of triple-negative breast cancer in man. The MaCSCs are capable of recapitulating tumorigenesis when transplanted at low multiplicities in vivo, and of forming self-renewing organoids in vitro. Expression profiling of the different subpopulations sorted from normal and neoplastic mammary tissues revealed that the normal stem cell compartment is more similar to tumor cells than to their own differentiated progenies. Accordingly, Wnt signaling was found to be activated in the subpopulation encompassing normal mammary stem cells, though to a lesser degree than in the tumor cells. By comparing normal with cancer mouse mammary compartments, we were able to derive a MaCSC-specific signature composed of human orthologous genes able to predict poor survival, relapse and distant metastasis in human breast cancer. Finally, upon intravenous injection, only MaCSCs among the different tumor cell subpopulations are able to form metastatic lesions in a broad spectrum of anatomical sites. Overall, our data indicate that constitutive Wnt signaling activation interferes with mammary stem cell homeostasis leading to metaplasia and basal-like adenocarcinomas.
Cancer stemness in Wnt-driven mammary tumorigenesis.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The male germ cell gene regulator CTCFL is functionally different from CTCF and binds CTCF-like consensus sites in a nucleosome composition-dependent manner.
Specimen part
View SamplesMiRNAs have the potential to regulate cellular differentiation programs. However, miRNA-deficiency in primary hematopoietic stem cells (HSCs) results in HSC depletion in mice, leaving the question of whether miRNAs play a role in early-lineage decisions unanswered. To address this issue, we deleted Dicer1, which encodes an essential RNaseIII enzyme for miRNA biogenesis, in murine CCAAT/enhancer-binding protein alpha (C/EBPA)-positive myeloid-committed progenitors in vivo. In contrast to the results in HSCs, we found that miRNA depletion affected neither the number of myeloid progenitors nor the percentage of C/EBPA-positive progenitor cells. Analysis of gene-expression profiles from wild type and Dicer1-deficient granulocyte-macrophage progenitors (GMPs) revealed that 20 miRNA families were active in GMPs. Of the derepressed miRNA targets in Dicer1-null GMPs, 27% are normally exclusively expressed in HSCs or are specific for multi-potent progenitors and erythropoiesis, indicating an altered gene-expression landscape. Dicer1-deficient GMPs were defective in myeloid development in vitro and exhibited an increased replating capacity, indicating a regained self-renewal potential of these cells. In mice, Dicer1 deletion blocked monocytic differentiation, depleted macrophages and caused myeloid dysplasia with morphological features of Pelger-Hut anomaly. These results provide evidence for a miRNA-controlled switch for a cellular program of self-renewal and expansion towards myeloid differentiation in GMPs.
Dicer1 deletion in myeloid-committed progenitors causes neutrophil dysplasia and blocks macrophage/dendritic cell development in mice.
Specimen part
View SamplesWe compared the transcriptomes of EpiSCs maintained in the presence or absence of Wnt pathway inhibitor IWP2. We screened also our gene expression data for potential markers for genuine EpiSCs, maintained in the presence of Wnt inhibition and compared with ESC expression data. We compared the transcriptomes of EpiSCs maintained in the presence or absence of IWP2. The high level of Wnt-induced differentiation occurring in conventional EpiSC cultures may have interfered with the analysis of their characteristics. By applying Wnt inhibitors we are now able to establish the properties of genuine EpiSCs.
Endogenous WNT signals mediate BMP-induced and spontaneous differentiation of epiblast stem cells and human embryonic stem cells.
Specimen part, Treatment
View SamplesBackground: The ubiquitin-conjugating enzyme HR6B is required for spermatogenesis in mouse. Loss of HR6B results in aberrant histone modification patterns on the trancriptionally silenced X and Y chromosomes (XY body) and on centromeric chromatin in meiotic prophase. We studied the relationship between these chromatin modifications and their effects on global gene expression patterns, in spermatocytes and spermatids.
No associated publication
Sex, Specimen part
View SamplesThe effect of CTCFL mutation on the transcriptional program in testes
The male germ cell gene regulator CTCFL is functionally different from CTCF and binds CTCF-like consensus sites in a nucleosome composition-dependent manner.
Specimen part
View SamplesTo identify cellular and genetic abnormalities involved in interstrand cross link repair-deficient bone marrow failure and its transformation to leukemia, we used an Ercc1 hypomorphic mouse model (Ercc1 -/d).
ICL-induced miR139-3p and miR199a-3p have opposite roles in hematopoietic cell expansion and leukemic transformation.
Age, Specimen part
View SamplesThe majority of sporadic colorectal cancer cases are initiated by mutations in the APC tumor suppressor gene leading to constitutive activation of the Wnt/b-catenin signaling pathway and adenoma formation. Several pre-clinical models carrying germline mutations in the endogenous mouse Apc tumor supressor gene have been generated and their phenotype characterized. The predisposition of these mouse models to multiple intestinal adenomas closely resembles the FAP phenotype at the molecular, cellular and phenotypic level and may prove valuable to elucidate the molecular and cellular mechanisms underlying colorectal tumorigenesis. The goal of this study is to establish an expression signature characteristic of intestinal tumors characterized by the inactivation of Apc.
Cross-species comparison of human and mouse intestinal polyps reveals conserved mechanisms in adenomatous polyposis coli (APC)-driven tumorigenesis.
Sex, Age, Specimen part
View Samples