The cellular origin of Ewing tumor (ET), a tumor of bone or soft tissues characterized by specific fusions between EWS and ETS genes, is highly debated. Through gene expression analysis comparing ETs with a variety of normal tissues, we show that the profiles of different EWS-FLI1-silenced Ewing cell lines converge toward that of mesenchymal stem cells (MSC). Moreover, upon EWS-FLI1 silencing, two different Ewing cell lines can differentiate along the adipogenic lineage when incubated in appropriate differentiation cocktails. In addition, Ewing cells can also differentiate along the osteogenic lineage upon long-term inhibition of EWS-FLI1. These in silico and experimental data strongly suggest that the inhibition of EWS-FLI1 may allow Ewing cells to recover the phenotype of their MSC progenitor.
Mesenchymal stem cell features of Ewing tumors.
Specimen part
View SamplesHuman mesenchymal stem cells (MSC) display a high potential for the development of novel treatment strategies for cartilage repair. However, the pathways involved in their differentiation to functional and non hypertrophic chondrocytes remain largely unknown, despite the work on embryologic development and the identification of key growth factors including members of the TGF, Hh, Wnt and FGF families. In this study, we asked if we could identify specific biological networks independently from the growth factor used (TGF-3 or BMP-2). To address this question, we used DNA microarrays and performed large-scale expression profiling of MSC at different time points during their chondral differentiation. By comparing these data with those obtained during their differentiation into osteoblasts and adipocytes, we identified 318 genes specific for chondrogenesis. We distributed the selected genes in 5 classes according to their kinetic of expression and used the Ingenuity software in order to identify new biological networks. We could reconstruct 3 phases for chondral differentiation, characterized by functional pathways. The first phase corresponds to cell attachment and apoptosis prevention with the up-regulation of 5 integrins, BCL6, NFIL3, RGS2 and down-regulation of CTGF and CYR61. The second phase is characterized by a proliferation/differentiation step with the continuous expression of MAF, PGF, HGMA1 or NOTCH3, CHI3L1, WNT5A, LEPR. Finally, the last step of differentiation/hypertrophy is characterized by expression of DKK1, APOD/E, SERPINF1 and TIMP4. These data propose new pathways to understand the complexity of MSC differentiation to chondrocytes and new potential targets for cell therapy applied to cartilage repair.
Gene expression profile of multipotent mesenchymal stromal cells: Identification of pathways common to TGFbeta3/BMP2-induced chondrogenesis.
No sample metadata fields
View SamplesWe have studied the plasma membrane protein phenotype of human culture-amplified and native Bone Marrow Mesenchymal Stem Cells (BM MSCs). We have found, using microarrays and flow cytometry, that cultured cells express specifically 113 transcripts and 17 proteins that were not detected in hematopoietic cells. These antigens define a lineage-homogenous cell population of mesenchymal cells, clearly distinct from the hematopoietic lineages, and distinguishable from other cultured skeletal mesenchymal cells (periosteal cells and synovial fibroblasts). Among the specific membrane proteins present on cultured MSCs, 9 allowed the isolation from BM mononuclear cells of a minute population of native MSCs. The enrichment in Colony-Forming Units-Fibroblasts was low for CD49b, CD90 and CD105, but high for CD73, CD130, CD146, CD200 and integrin alphaV/beta5. Additionally, the expression of CD73, CD146 and CD200 was down-regulated in differentiated cells. The new marker CD200, because of its specificity and immunomodulatory properties, deserves further in depth studies.
Specific plasma membrane protein phenotype of culture-amplified and native human bone marrow mesenchymal stem cells.
Sex, Age, Specimen part, Treatment
View SamplesPurpose: The population of muscle-derived stem cells called MuStem cells is presented as promising candidate for cell-based therapy of muscle diseases. To validate if this agent can be really presented as therapeutic product and so to be eligible to a future clinical use, it is now required to demonstrate beforehand an efficacy with cells prepared in compliance with good manufacturing practices (GMPs). The aim of the current study was to evaluate the use of two xeno-free blood derivatives corresponding to human serum (HS) and human platelet lysate (hPL) as alternatives to controverted but until now used fetal bovine serum (FBS) for isolation and expansion of human MuStem (hMuStem) cells. Methods: A comparative study was performed with hMuStem cells isolated and in vitro expanded by using commercially available HS and hPL to determine its impact on their proliferation rates, clonogenicity, myogenic commitment level and oligopotency with regard to results obtained under FBS-based medium. Also, their respective phenotype and global gene expression patterns were investigated by flow cytometry and high throughput 3' digital gene expression RNA-sequencing in order to define a possible differential impact of the human nutrients tested. Results: Comparatively to FBS-based medium, use of HS- and hPL-supplemented ones efficiently supported long-term proliferation of hMuStem cells and enhanced clonogenicity, without main modification of their expression profile and allowing besides limiting the supplementation in growth factors. In vitro differentiation assay combined to transforming growth factor ß1 (TGF-ß1)-depletion experiments showed a lower myogenic commitment level as well as fusion ability of hMuStem cells when cultured with hPL-based medium according to a TGF-ß1-independent process. Use of hPL-derived 3D hydrogel or fibrinogen-depleted hPL demonstrated that heparin-free hPL derivatives maintain consequent myogenic differentiation potential. In addition, the reduced myogenicity was shown to be rapidly reversible following replacement of hPL by HS or fibrinogen-depleted hPL. Conclusions: All together, our original findings position HS and hPL as efficient and suitable alternatives to FBS for preparation of hMuStem cell batch in compliance with GMPs. Overall design: mRNA profile of hMuStem cells cultured in hPL was compared to the mRNA profile of hMuStem cells cultured in HS. The profiles were generated in triplicates using the 3''DGE-Seq technology.
Human serum and platelet lysate are appropriate xeno-free alternatives for clinical-grade production of human MuStem cell batches.
Specimen part, Subject
View SamplesWe previously identified multipotent stem cells within the lamina propria of the human olfactory mucosa, located in the nasal cavity. We also demonstrated that this cell type differentiates into neural cells and improves locomotor behavior after transplantation in a rat model of Parkinsons disease. Yet, next to nothing is known about their specific stemness characteristics. We therefore devised a study aiming to compare olfactory lamina propria stem cells from 4 individuals to bone marrow mesenchymal stem cells from 4 age- and gendermatched individuals. Using pangenomic microarrays and immunostaining with 34 cell surface marker antibodies, we show here that olfactory stem cells are closely related to bone marrow stem cells. However, olfactory stem cells exhibit also singular traits. By means of techniques such as proliferation assay, cDNA microarrays, RT-PCR, in vitro and in vivo differentiation, we report that, when compared to bone marrow stem cells, olfactory stem cells display i) a high proliferation rate; ii) a propensity to differentiate into osseous cells and iii) a disinclination to give rise to chondrocytes and adipocytes. Since peripheral olfactory stem cells originate from a neural crest-derived tissue and, as shown here, exhibit an increased expression of neural cellrelated genes, we propose to name them olfactory ecto-mesenchymal stem cells (OE-MSC). Further studies are now required to corroborate the therapeutic potential of OE-MSCs in animal models of bone and brain diseases.
The human nose harbors a niche of olfactory ectomesenchymal stem cells displaying neurogenic and osteogenic properties.
Sex, Age, Specimen part, Treatment
View SamplesGene expression profiling of the medial (MGE), lateral (LGE) and caudal (CGE) ganglionic eminence, and cerebral cortex (CTX) at various embryonic stages (E12.5, E14 and E16).
Comprehensive spatiotemporal transcriptomic analyses of the ganglionic eminences demonstrate the uniqueness of its caudal subdivision.
Sex, Specimen part
View SamplesExpression in GFP vs. GFP/hTERT transduced CD8 T Lymphocytes from Healty Donors (HD) 1 and 2 at early and late passages. Using CD8+ T lymphocyte clones over-expressing telomerase we investigated the molecular mechanisms that regulate T cell proliferation. Transduction and subcloning procedures were performed on CD8 + naive T-cell clones isolated from two different healthy individuals aged between 30 to 35 years (HD1 and HD2). T-cell cloneswere transduced to express hTERT/GFP or GFP alone.
Mechanisms regulating the proliferative potential of human CD8+ T lymphocytes overexpressing telomerase.
No sample metadata fields
View SamplesUsing CD8+ T lymphocyte clones over-expressing telomerase weinvestigated the molecular mechanisms that regulate T cell proliferation. Transduction and subcloning procedures were performed on CD8 + naive T-cell clones isolated from two different healthy individuals aged between 30 to 35 years (HD1 and HD2). T-cell cloneswere transduced to express hTERT/GFP or GFP alone. HD2 was profiled on U133Plus 2.0 and submitted as a separate GEO series.
Mechanisms regulating the proliferative potential of human CD8+ T lymphocytes overexpressing telomerase.
No sample metadata fields
View SamplesUsing CD8+ T lymphocyte clones over-expressing telomerase weinvestigated the molecular mechanisms that regulate T cell proliferation. Transduction and subcloning procedures were performed on CD8 + naive T-cell clones isolated from two different healthy individuals aged between 30 to 35 years (HD1 and HD2). T-cell cloneswere transduced to express hTERT/GFP or GFP alone. HD1 was profiled on U133A and submitted as a separate GEO series.
Mechanisms regulating the proliferative potential of human CD8+ T lymphocytes overexpressing telomerase.
No sample metadata fields
View SamplesTo study the effect of balanced chromosomal rearrangements on gene expression, we compared the transcriptomes of cell lines from control and t(11;22)(q23;q11) individuals. This translocation between chromosomes 11 and 22 is the only recurrent constitutional non-Robertsonian translocation in humans. The number of differentially expressed transcripts between the translocated and control cohort is significantly higher than that observed between control samples alone, suggesting that balanced rearrangements have a greater effect on gene expression than normal variation. Altered expression is not limited to genes close to the translocation breakpoint suggesting that a long-range effect is operating. Indeed we show that the nuclear position of the derivative chromosome is altered compared to the normal chromosomes. Our results are consistent with recent studies that indicate a functional role for nuclear position in regulating the expression of some genes in mammalian cells. They may also have implications on reproductive separation, as we show that reciprocal translocations not only provide partial isolation for speciation but also significant changes in transcriptional regulation through alteration of nuclear chromosomes territories.
The effect of translocation-induced nuclear reorganization on gene expression.
Sex, Age, Specimen part
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