The Philadelphia chromosome (Ph) encoding the oncogenic BCR-ABL1 kinase defines a subset of ALL with a particularly unfavorable prognosis. Acute lymphoblastic leukemia (ALL) cells are derived from B cell precursors in most cases and typically carry rearranged immunglobulin heavy chain (IGH) variable (V) region genes devoid of somatic mutations. Somatic hypermutation is restricted to mature germinal center B cells and depends on activation-induced cytidine deaminase (AID). Studying AID expression in 108 cases of ALL, we detected AID mRNA in 24 of 28 Ph-positive ALLs as compared to 6 of 80 Ph-negative ALLs. Forced expression of BCR-ABL1 in Ph-negative ALL cells and inhibition of the BCR-ABL1-kinase showed that aberrant expression of AID depends on BCR-ABL1 kinase activity. Consistent with aberrant AID expression in Ph-positive ALL, IGH V region genes and BCL6 were mutated in many Ph-positive but unmutated in most Ph-negative cases. In addition, AID introduced DNA-single-strand breaks within the tumor suppressor gene CDKN2B in Ph-positive ALL cells, which was sensitive to BCR-ABL1 kinase inhibition and silencing of AID expression by RNA interference. These findings identify AID as a BCR-ABL1-induced mutator in Ph-positive ALL cells, which may be relevant with respect to the particularly unfavorable prognosis of this leukemia subset.
Activation-induced cytidine deaminase acts as a mutator in BCR-ABL1-transformed acute lymphoblastic leukemia cells.
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View SamplesThe normal growth and function of mammary epithelial cells depend on interactions with the supportive stroma. Alterations in this communication can lead to the progression or expansion of malignant growth. The human mammary gland contains two distinctive types of fibroblasts within the stroma. The epithelial cells are surrounded by loosely connected intralobular fibroblasts, which are subsequently surrounded by the more compacted interlobular fibroblasts. The different proximity of these fibroblasts to the epithelial cells suggests distinctive functions for these two subtypes. In this report, we compared the gene expression profiles between the two stromal subtypes.
Interlobular and intralobular mammary stroma: genotype may not reflect phenotype.
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View SamplesBackground: Here, the role of a-ketoglutarate (aKG) in the epi-metabolic control of DNA demethylation has been investigated in therapeutically relevant cardiac mesenchymal cells (CMSCs) isolated from controls and type 2 diabetes donors. Methods & results: Quantitative global analysis, methylated and hydroxymethylated DNA sequencing and gene specific GC methylation detection revealed an accumulation of 5mC, 5hmC and 5fC in the genomic DNA of human CMSCs isolated from diabetic (D) donors (D-CMSCs). Whole heart genomic DNA analysis revealed iterative oxidative cytosine modification accumulation in mice exposed to high fat diet (HFD), injected with streptozotocin (STZ) or both in combination (STZ-HFD). In this context, untargeted and targeted metabolomics indicated an intracellular reduction of aKG synthesis in D-CMSCs and in the whole heart of HFD mice. This observation was paralleled by a compromised thymine DNA glycosylase (TDG) and ten eleven translocation protein 1 (TET1) association and function with TET1 relocating out of the nucleus. Molecular dynamics and mutational analyses showed that aKG binds TDG on Arg275 providing an enzymatic allosteric activation. As a consequence, the enzyme significantly increased its capacity to remove G/T nucleotide mismatched or 5fC. Accordingly, an exogenous source of aKG restored the DNA demethylation cycle by promoting TDG function, TET1 nuclear localization and TET/TDG association. TDG inactivation by CRISPR/Cas9 knockout or TET/TDG siRNA knockdown induced 5fC accumulation thus partially mimicking the diabetic epigenetic landscape in cells of non- diabetic origin. The novel compound (S)-2-[(2,6-dichlorobenzoyl)amino]succinic acid (AA6), identified as an inhibitor of aKG-dehydrogenase, increased the aKG level in D- CMSCs and in the heart of HFD mice eliciting DNA demethylation, glucose uptake and insulin response. Conclusions: In this report we established that diabetes may epigenetically modify and compromise function of therapeutically relevant cardiac mesenchymal cells. Restoring the epi-metabolic control of DNA demethylation cycle promises beneficial effects on cells compromised by environmental metabolic changes. Overall design: Human primary cardiac mesenchymal cells (CMSC) from 7 diabetic (D) and 7 non-diabetic (ND) donors were analyzed after few rounds of ex vivo expansion. RNA was isolated and sequenced.
Stable Oxidative Cytosine Modifications Accumulate in Cardiac Mesenchymal Cells From Type2 Diabetes Patients: Rescue by α-Ketoglutarate and TET-TDG Functional Reactivation.
Specimen part, Subject
View SamplesWe disprove that the impaired Myd88-dependent proinflammatory response of neonatal monocytes is a correlate for immaturity and confirm it as display of transient alarmin-mediated stress tolerization. We find a strong inducibility of TRIF-dependent genes in neonatal monocytes by LPS but a barely detectable expression at baseline.
S100-alarmin-induced innate immune programming protects newborn infants from sepsis.
Specimen part, Treatment
View SamplesIn order to identify genes that are activated in differentiating WT ESCs, but are missing in Tal-1-/- and Runx1-/- ESCs, and which might be involved in the generation of definitive hematopoietic progenitors and their specification thereafter, we performed microarray analyses on purified Flk-1+ cells, differentiated from these ESCs for 4, 5, and 6 days in vitro.
Ectopic Runx1 expression rescues Tal-1-deficiency in the generation of primitive and definitive hematopoiesis.
Specimen part, Cell line, Time
View SamplesEwing sarcoma family of tumors (ESFT) are aggressive bone and soft tissue tumors of unknown cellular origin. Most ESFT express EWS-FLI1, a chimeric protein which functions as a growth-promoting oncogene in ESFT but is toxic to most normal cells. A major difficulty in understanding EWS-FLI1 function has been the lack of an adequate model in which to study EWS-FLI1-induced transformation. Although the cell of origin of ESFT remains elusive, both mesenchymal (MSC) and neural crest (NCSC) have been implicated. We recently developed the tools to generate NCSC from human embryonic stem cells (hNCSC). In the current study we used this model to test the hypothesis that neural crest-derived stem cells are the cells of origin of ESFT and to evaluate the consequences of EWS-FLI1 expression on human neural crest biology.
Modeling initiation of Ewing sarcoma in human neural crest cells.
Specimen part
View SamplesIntracranial B16 melanoma tumors isolated from C57Bl6 mice were analyzed by mRNAseq. Four experimental groups were analyzed: (1) Mice with intracranial tumors receiving IgG; (2) Mice with intracranial tumors receiving anti-PD-1 plus anti-CTLA-4 therapy; (3) Mice with intracranial plus extracranial tumors receiving IgG; (4) Mice with intracranial plus extracranial tumors receiving anti-PD-1 plus anti-CTLA-4 therapy. Taggart et al., PNAS 2018; Overall design: mRNAseq profiles of intracranial B16 tumours at day 9 post-cancer cell implantation were generated for 4 different experimental groups (biological triplicates)
Anti-PD-1/anti-CTLA-4 efficacy in melanoma brain metastases depends on extracranial disease and augmentation of CD8<sup>+</sup> T cell trafficking.
Specimen part, Cell line, Treatment, Subject
View SamplesPatients relapsing with FLT3-ITD mutant acute myeloid leukemia (AML) after allogeneic hematopoietic cell transplantation (allo-HCT) have a one-year-survival below 20%. We observed that sorafenib increased IL-15 production by FLT3-ITD+-leukemia cells, which synergized with the allogeneic CD8+T-cell response, leading to long-term survival in murine and humanized FLT3-ITD+AML models. Using IL-15 deficiency in recipient tissues or leukemia cells, IL-15 production upon sorafenib-treatment could be attributed to leukemia cells. Sorafenib treatment-related IL-15 production caused an increase in CD8+CD107a+IFN-+ T-cells with features of longevity (Bcl-2high/reduced PD-1-levels), which eradicated leukemia in secondary recipients. Mechanistically, sorafenib reduced ATF4 expression, thereby blocking negative regulation of IRF7-activation, which enhances IL-15 transcription. Consistent with the mouse data, IL-15 and pIRF7 levels increased in leukemic blasts of FLT3-ITD+AML patients upon sorafenib treatment. Analysis of 130 patients with FLT3-ITD-mutant AML relapsing after allo-HCT showed the highest complete remission-rate and median overall-survival-rate in the sorafenib/donor lymphocyte infusion (DLI) group compared to all other groups (chemotherapy, chemotherapy/DLI, sorafenib alone). Our findings indicate that the synergism of DLI and sorafenib is mediated via reduced ATF4 expression, causing activation of the pIRF7/IL-15-axis in leukemia cells. The sorafenib/DLI strategy therefore has the potential for an immune-mediated cure of FLT3-ITD-mutant AML- relapse, an otherwise fatal complication after allo-HCT.
Sorafenib promotes graft-versus-leukemia activity in mice and humans through IL-15 production in FLT3-ITD-mutant leukemia cells.
Specimen part, Treatment, Time
View SamplesInflammatory mediators play a role in the pathogenesis/progression of chronic heart failure (CHF). The aim of the present study was to identify diagnostic/prognostic markers and gene expression profiles of CHF vs control.
Gene expression profiles in peripheral blood mononuclear cells of chronic heart failure patients.
No sample metadata fields
View SamplesTo understand differences between resting and activated memory CD8+ T cells, we compared the global gene expression of ex vivo isolated naive and spleen and BM memory cells to in vitro activated spleen and BM memory cells.
Memory CD8(+) T cells colocalize with IL-7(+) stromal cells in bone marrow and rest in terms of proliferation and transcription.
Sex, Specimen part
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