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 SamplesThe identification of subtype-specific translocations has revolutionized diagnostics of sarcoma and provided new insight into oncogenesis. We used RNA-Seq to investigate samples diagnosed as small round cell tumors of bone, possibly Ewing sarcoma, but lacking the canonical EWSR1-ETS translocation. A new fusion was observed between the BCL6 co-repressor (BCOR) and the testis specific cyclin B3 (CCNB3) genes on chromosome X. RNA-Seq results were confirmed by RT-PCR and cloning the tumor-specific genomic translocation breakpoints. 24 BCOR-CCNB3-positive tumors were identified among a series of 594 sarcomas. Gene profiling experiments indicate that BCOR-CCNB3-positive cases are biologically distinct from other sarcomas, particularly Ewings sarcoma. Finally, we show that CCNB3 immunohistochemistry is a powerful diagnostic marker for this group of sarcoma and that over-expression of BCOR-CCNB3 or of a truncated CCNB3 activates S-phase in NIH3T3 cells. Thus the intrachromosomal X fusion described here represents a new subtype of bone sarcoma caused by a novel gene fusion mechanism.
A new subtype of bone sarcoma defined by BCOR-CCNB3 gene fusion.
Sex, Age, Specimen part
View SamplesIdentification of druggable targets is a prerequisite for developing targeted therapies against Ewing sarcoma. We report the identification of Protein Kinase C Beta (PRKCB) as a protein specifically and highly expressed in Ewing sarcoma as compared to other pediatric cancers. Its transcriptional activation is directly regulated by the EWSR1-FLI1 oncogene. Getting insights in PRKCB activity we show that, together with PRKCA, it is responsible for the phosphorylation of histone H3T6, allowing global maintenance of H3K4 trimethylation on a variety of gene promoters. In the long term, PRKCB RNA interference induces apoptosis in vitro. More importantly, in xenograft mice models, complete impairment of tumor engraftment and even tumor regression were observed upon PRKCB inhibition, highlighting PRKCB as a most valuable therapeutic target. Deciphering PRKCB roles in Ewing sarcoma using expression profiling, we found a strong overlap with genes modulated by EWSR1-FLI1 and an involvement of RPKCB in regulating crucial signaling pathways. Altogether, we show that PRKCB may have two important independent functions and should be considered as highly valuable for understanding Ewing sarcoma biology and as a promising target for new therapeutic approaches in Ewing sarcoma.
Targeting the EWSR1-FLI1 oncogene-induced protein kinase PKC-β abolishes ewing sarcoma growth.
Cell line
View SamplesThe purpose of this study was to define biomarkers of sensitivty and mechanisms of resistance to the KDM1A/LSD1 inhibtor SP-2509 (HCI-2509) in Ewing sarcoma cell lines. We report that regardless of drug sensitivity all cell lines engage the UPR and ER-stress response following treatment with SP-2509 resulting in apoptotic cytotoxicity. In addition hypersentsitive cell lines shared a common basal transcriptnomic profile, with hypersensitive cell lines signficantly inducing ETS1 which was not observed in sensitive cell lines. Overall design: 6 Ewing sarcoma cell lines were treated with either vehicle control (DMSO) or the reversible LSD1/KDM1A inhibitor SP-2509 (2uM) for 48hrs. Three SP-2509 hypersensitive (IC50< 300nM)(A673, TC32, TC252) and three SP-2509 sensitive (IC50>900nM) (EWS-502, ES-2 and TC71) cell lines were investigated. Paired RNA from three indpendent experiments per cell line was analyzed.
Therapeutic Targeting of KDM1A/LSD1 in Ewing Sarcoma with SP-2509 Engages the Endoplasmic Reticulum Stress Response.
Treatment, Subject
View SamplesFor this study, we selected, from the French Sarcoma Group (FSG) database, soft tissue sarcomas with no recurrent chromosomal translocations and for which a frozen tissue of the untreated primary tumor was available. Three hundred and ten sarcomas have been studied. They are split in two cohorts.
Validated prediction of clinical outcome in sarcomas and multiple types of cancer on the basis of a gene expression signature related to genome complexity.
Specimen part, Disease, Time
View SamplesExpression profiling of Ewing sarcoma samples in the frame of the CIT program from the french Ligue Nationale Contre le Cancer (http://cit.ligue-cancer.net).
Common variants near TARDBP and EGR2 are associated with susceptibility to Ewing sarcoma.
Sex, Age
View SamplesThe transition from progenitor to differentiated cells is critical for successful organogenesis; subtle alterations in this process can lead to developmental disorders. The anterior heart field (AHF) encompasses a niche in which cardiac progenitors maintain their multipotent and undifferentiated nature by signals from the surrounding tissues, which thus far have been poorly defined. Using systems biology approaches and perturbations of signaling molecules in chick embryos, we revealed a tight crosstalk between the bone morphogenic protein (BMP) and fibroblast growth factor (FGF) signaling pathways within the AHF: BMP4 promotes myofibrillar gene expression and cardiomyocyte contractions, by blocking FGF signaling. Furthermore, inhibition of the FGF-ERK pathway is both sufficient and necessary for these processes, suggesting that FGF signaling blocks premature differentiation of cardiac progenitors in the AHF. Investigating the molecular mechanisms downstream to BMP signaling revealed that BMP4 induced a set of neural crest-related genes; including MSX1, which was sufficient to induce cardiomyocyte differentiation. We suggest that BMP and FGF signaling pathways act via inter- and intra-regulatory loops in multiple tissues, to coordinate the balance between proliferation and differentiation of cardiac progenitors.
BMP-mediated inhibition of FGF signaling promotes cardiomyocyte differentiation of anterior heart field progenitors.
No sample metadata fields
View SamplesTo get insight in the functional role of EGR2 for Ewing sarcoma, we performed a transcriptional profiling of Ewing sarcoma cells after knockdown of EGR2 and compared the resulting transcriptional signature with that of EWSR1-FLI1-silenced Ewing sarcoma cells. In accordance with the strong EGR2-induction by EWSR1-FLI1, both genes highly significantly overlap in their transcriptional signatures. Gene-set enrichment analyses (GSEA) and DAVID (Database for Annotation, Visualisation and Integrated Discovery) gene ontology analyses indicated a strong impact of EGR2 on cholesterol and lipid biosynthesis resembling its function in orchestrating lipid metabolism of myelinating Schwann cells.
Chimeric EWSR1-FLI1 regulates the Ewing sarcoma susceptibility gene EGR2 via a GGAA microsatellite.
Cell line, Treatment
View SamplesDuring its long infection cycle, human cytomegalovirus (HCMV) extensively manipulates cellular gene expression to maintain conditions favorable for viral propagation. In order to reveal the signature of cellular genes that are manipulated by HCMV, we measured RNA abundance and rate of protein production through the course of HCMV infection. We characterized changes for most expressed cellular genes and although much of the regulation was transcriptional we uncover diverse and dynamic translational regulation for subsets of host genes, revealing unappreciated coordination in translational control that suggests common regulators Overall design: Ribosome profiling and mRNA-seq along HCMV infection
The Transcription and Translation Landscapes during Human Cytomegalovirus Infection Reveal Novel Host-Pathogen Interactions.
No sample metadata fields
View SamplesA cell supsension containing an equal mix of HEK and 3T3 cells was used in the Fluidigm C1 Overall design: Suspensions of 3T3 and HEK cells were diluted down to a concentration of 250,000 per mL and mixed 1:1, then loaded onto two medium C1 cell capture chips.
Highly Parallel Genome-wide Expression Profiling of Individual Cells Using Nanoliter Droplets.
No sample metadata fields
View Samples