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GSE65941
Homo sapiens
18 Downloadable Samples
Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
The synthesis and processing of mRNA, from transcription to translation initiation, often requires splicing of intragenic material. The final mRNA composition varies based upon proteins that modulate splice site selection. EWS-FLI1 is an Ewing sarcoma (ES) oncogene with an interactome that we demonstrate to have multiple partners in spliceosomal complexes. We evaluate EWS-FLI1 upon post-transcriptional gene regulation using both exon array and RNA-seq. Genes that potentially regulate oncogenesis including CLK1, CASP3, PPFIBP1, and TERT validate as alternatively spliced by EWS-FLI1. EWS-FLI1 also alters splicing by directly binding to known splicing factors including DDX5, hnRNPK, and PRPF6. Reduction of EWS-FLI1 produces an isoform of g-TERT that has increased telomerase activity compared to WT TERT. The small molecule YK-4-279 is an inhibitor of EWS-FLI1 oncogenic function that disrupts specific protein interactions including DDX5 and RNA helicase A (RHA) that alters RNA splicing ratios. As such, YK-4-279 validates the splicing mechanism of EWS-FLI1 showing alternatively spliced gene patterns that significantly overlap with EWS-FLI1 reduction and WT human mesenchymal stem cells. Exon array analysis of 75 ES patient samples show similar isoform expression patterns to cell line models expressing EWS-FLI1, supporting the clinical relevance of our findings. These experiments establish systemic alternative splicing as an oncogenic process modulated by EWS-FLI1. EWS-FLI1 modulation of mRNA splicing may provide insight into the contribution of splicing towards oncogenesis, and reciprocally, EWS-FLI1 interactions with splicing proteins may inform the splicing code.
Publication Title
Oncogenic fusion protein EWS-FLI1 is a network hub that regulates alternative splicing.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 16 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
We have discovered frequent genetic inactivation of the STAG2 gene in diverse human cancers including glioblastoma, Ewing's sarcoma, and melanoma. STAG2 encodes a subunit of the sister chromatid cohesion complex called the "cohesin complex" that is responsible for the cohesion of sister chromatids following DNA replication and is cleaved at the metaphase to anaphase transition to enable chromosome segregation into daughter cells. Interestingly, the cohesin complex has also been implicated as a regulator of chromatin architecture and transcription. To determine the functional significance of STAG2 inactivation in cancer pathogenesis, we used somatic cell gene targeting to correct the endogenous mutations of STAG2 in two aneuploid human glioblastoma cell lines, H4 and 42MGBA. Similarly, somatic cell gene targeting was also used to introduce a nonsense mutation into codon 6 of the endogenous wild-type allele of STAG2 in HCT116 cells, a near-diploid human colorectal cancer cell line with stable karyotype. Expression profiling of these three paired sets of STAG2-proficient and deficient cells demonstrated that STAG2 does not play a global role in transcriptional regulation nor does it recurrently modulate the expression of specific tumor-promoting or suppressing genes.
Publication Title
Mutational inactivation of STAG2 causes aneuploidy in human cancer.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 3 Downloadable Samples
Illumina HiSeq 2500
Description
A chimeric fusion between the RNA binding protein EWS and the ETS family transcription factor FLI1 (EWS-FLI1), created from a chromosomal translocation, is implicated in driving the majority of Ewing sarcomas (ES) by modulation of transcription and alternative splicing. The small molecule YK-4-279 inhibits EWS-FLI1 function and induces apoptosis. We tested 69 anti-cancer drugs in combination with YK-4-279 and found that vinca alkaloids exhibited synergy with YK-4-279 in five ES cell lines. The combination of YK-4-279 and vincristine reduced tumor burden and increased survival in mice bearing ES xenografts. We determined that independent drug-induced events converged to cause this synergistic therapeutic effect. YK-4-279 rapidly induced G2/M arrest, increased the abundance of cyclin B1, and decreased EWS-FLI1–mediated expression of microtubule-associated proteins, which rendered cells more susceptible to microtubule depolymerization by vincristine. YK-4-279 reduced the expression of the EWS-FLI1 target gene encoding ubiquitin ligase UBE2C, and this in part contributed to the increase in cyclin B1. Biochemical assays revealed that YK-4-279 also increased the abundance of proapoptotic isoforms of MCL1 and BCL2, presumably through inhibition of alternative splicing by EWS-FLI1, thus promoting cell death in response to vincristine. Thus a combination of vincristine and YK-4-279 might be therapeutically effective in ES patients. Overall design: Examination of mRNA profiles of TC32 on knockdown of EWS-FLI1 or treatment with YK-4-279: 3 samples Total: 1 TC32 WT Control, 1 TC32 shEF, 1 TC32 YK
Publication Title
Inhibition of the oncogenic fusion protein EWS-FLI1 causes G<sub>2</sub>-M cell cycle arrest and enhanced vincristine sensitivity in Ewing's sarcoma.
Sample Metadata Fields
Cell line, Subject
View Samples- Homo sapiens
- 27 Downloadable Samples
- IlluminaHiSeq2000
Description
Ewing's sarcoma family of tumors (ESFT) is an aggressive pediatric bone and soft tissue cancer. It is the prototypical example of mesenchymal tumors driven by a fusion oncogene involving the ewing sarcoma break point region 1 (EWSR1) gene, most frequently– EWS-FLI1. We have discovered that loss of EWSR1 leads to accumulation of R-loops, replication stress and impaired homologous recombination, recapitulating breast cancer 1, early onset (BRCA1) deficiency. EWS-FLI1 acts dominant negatively in ESFT to impart the same phenotypes. Further we demonstrate that in ESFT, BRCA1 predominantly associates with the elongating transcription machinery and is unavailable for DNA strand break repair. Gene expression profiling identified upregulated compensatory mechanisms in ESFT cells to process increased R-loops (RNASEH2 and FEN1) and replication stress (Fanconi Anemia). Taken together, our data identifies BRCA1 sequestration due to transcription stress as the mechanistic basis for ESFT chemosensitivity and suggests potential targets for the much lacking second-line therapy. Overall design: Examination of gene expression of four ESFT cell lines and two control cell lines. Cells were treated to LD65 dose of etoposideand samples collected at 6 hour intervals over 24 hours
Publication Title
EWS-FLI1 increases transcription to cause R-loops and block BRCA1 repair in Ewing sarcoma.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Gene 1.1 ST Array (hugene11st)
Description
In vitro expansion of adult human islet cells is an attractive solution for the shortage of tissue for cell replacement therapy of type 1 diabetes. Using a lineage tracing approach, we have demonstrated that -cell-derived (BCD) cells rapidly dedifferentiate in culture and can proliferate for up to 16 population doublings. Dedifferentiation is associated with changes resembling epithelial-mesenchymal transition (EMT). The WNT pathway has been shown to induce EMT and plays key roles in regulating replication and differentiation in many cell types. Here we show that BCD cell dedifferentiation is associated with -catenin translocation into the nucleus and activation of the WNT pathway. Inhibition of -catenin expression in expanded BCD cells using short hairpin RNA resulted in growth arrest, mesenchymal-epithelial transition, and redifferentiation, as judged by activation of -cell gene expression. Furthermore, inhibition of -catenin expression synergized with redifferentiation induced by a combination of soluble factors, as judged by an increase in the number of C-peptide-positive cells. Simultaneous inhibition of the WNT and NOTCH pathways also resulted in a synergistic effect on redifferentiation. These findings, which were reproducible in cells derived from multiple human donors, suggest that inhibition of the WNT pathway may contribute to a therapeutically applicable way for generation of functional insulin-producing cells following ex-vivo expansion.
Publication Title
Redifferentiation of adult human β cells expanded in vitro by inhibition of the WNT pathway.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Homo sapiens
- 60 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Gene expression was influenced most by the tissue source, followed by culture methodology, next by location where the cells were cultured and lastly the donor variability.
Publication Title
The impact of cell source, culture methodology, culture location, and individual donors on gene expression profiles of bone marrow-derived and adipose-derived stromal cells.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
We used a microarray to examine the global gene expression profile of MCF7 cells grown in 2D and 3D culture conditions. Our goal was to identify changes in the expression of genes that regulate iron metabolism when cellular spatial organization was altered.
Publication Title
Contribution of three-dimensional architecture and tumor-associated fibroblasts to hepcidin regulation in breast cancer.
Sample Metadata Fields
Age, Specimen part, Cell line
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Expansion of beta cells from the limited number of adult human islet donors is an attractive prospect for increasing cell availability for cell therapy of diabetes. However, while evidence supports the replicative capacity of adult beta cells in vivo, attempts at expanding human islet cells in tissue culture resulted in loss of beta-cell phenotype. Using a genetic lineage-tracing approach we have provided evidence for massive proliferation of beta-cell-derived (BCD) cells within these cultures. Expansion involves dedifferentiation resembling epithelial-mesenchymal transition (EMT). Epigenetic analyses indicate that key beta-cell genes maintain a partially open chromatin structure in expanded BCD cells, although they are not transcribed. Here we report that BCD cells can be induced to redifferentiate by a combination of soluble factors. The redifferentiated cells express beta-cell genes, store insulin in typical secretory vesicles, and release it in response to glucose. The redifferentiation process involves mesenchymal-epithelial transition, as judged from changes in gene expression. Moreover, inhibition of the EMT effector SLUG using shRNA results in stimulation of redifferentiation. BCD cells also give rise at a low rate to cells expressing other islet hormones, suggesting transition through an islet progenitor-like stage during redifferentiation. These findings suggest that ex-vivo expansion of adult human islet cells is a promising approach for generation of insulin-producing cells for transplantation, as well as basic research, toxicology studies, and drug screening.
Publication Title
Insulin-producing cells generated from dedifferentiated human pancreatic beta cells expanded in vitro.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 9 Downloadable Samples
- Illumina HiSeq 2500
Description
Background. More than one million women in fertile age are infected with Trypanosoma cruzi worldwide. Anti-T.cruzi seropositivity in mothers has been associated with adverse pregnancy outcome but there is still a knowledge gap regarding this effect. Our aim was to compare the gene expression profile of term placental environment from T. cruzi seropositive (SP) and seronegative (SN) mothers. Methods. A RNA-Seq was performed in 9 pools of 2 different placental RNA samples each: 3 belonging to placentas from SN and 6 from SP. Each pool consisted of a binomial of a female/male newborn and a vaginal/caesarean delivery. None of the newborns resulted infected. Results. Only 42 genes showed a significant fold change between SP and SN groups. Among the down-regulated genes were KISS1 and CGB5. In the up-regulated genes group were: KIF12, HLA-G, PRG2, TAC3, FN1 and ATXN3L. To identify pathways significantly associated with maternal T. cruzi-infection, a gene-set association analysis was implemented. The placental environment transcriptomic profile of SP consisted of an enrichment in immunological genes sets (inflammatory response and lymphocytic activation were over-expressed) whereas numerous biosynthetic processes were down-regulated. Conclusions. It is worth noting that several differentially expressed genes in SP placentas code for proteins associated to preeclampsia and miscarriage. This first transcriptomics study in human term placental environment from non-infected deliveries shows a placental response that may affect the faetus while protecting it from the parasite infection; this host response could be responsible for the low rate of congenital transmission observed in human chronic Chagas disease. Background. More than one million women in fertile age are infected with Trypanosoma cruzi worldwide. Anti-T.cruzi seropositivity in mothers has been associated with adverse pregnancy outcome but there is still a knowledge gap regarding this effect. Our aim was to compare the gene expression profile of term placental environment from T. cruzi seropositive (SP) and seronegative (SN) mothers. Methods. A RNA-Seq was performed in 9 pools of 2 different placental RNA samples each: 3 belonging to placentas from SN and 6 from SP. Each pool consisted of a binomial of a female/male newborn and a vaginal/caesarean delivery. None of the newborns resulted infected. Results. Only 42 genes showed a significant fold change between SP and SN groups. Among the down-regulated genes were KISS1 and CGB5. In the up-regulated genes group were: KIF12, HLA-G, PRG2, TAC3, FN1 and ATXN3L. To identify pathways significantly associated with maternal T. cruzi-infection, a gene-set association analysis was implemented. The placental environment transcriptomic profile of SP consisted of an enrichment in immunological genes sets (inflammatory response and lymphocytic activation were over-expressed) whereas numerous biosynthetic processes were down-regulated. Conclusions. It is worth noting that several differentially expressed genes in SP placentas code for proteins associated to preeclampsia and miscarriage. This first transcriptomics study in human term placental environment from non-infected deliveries shows a placental response that may affect the faetus while protecting it from the parasite infection; this host response could be responsible for the low rate of congenital transmission observed in human chronic Chagas disease. Overall design: Serodiagnosis of pregnant women was done by means of conventional serological methods and carried out by the respective health centres based on routine assays. In maternal and umbilical cord blood samples T. cruzi presence was tested using multiplex Real Time PCR as previously described [6]. Maternal infection with other pathogens that produce congenital transmission and adverse pregnancy outcome were considered as exclusion criteria, as well as missing data or incorrect sampling. Fresh normal placentas were obtained after labour from vaginal or caesarean deliveries and placed within 24 hours at 4°C. Each placenta was dissected and the middle section [7] at 2 cm distance from the umbilical cord was isolated and placed into RNAlater solution (Applied Biosystems, Foster City, CA). Total RNA was extracted with TRIzol reagent (Invitrogen, Carlsbad, CA) and stored at -80°C until used. Transcriptomic studies. A RNA-Seq experiment was done in 9 pools of 2 different placental RNA samples each: 3 pools (C1, C2 and C3) belonging to placentas from seronegative mothers (SN) and 6 pools (TC4 to TC9) from seropositive mothers (SP). Each pool consisted of a binomial of a female/male newborn and a vaginal/caesarean delivery. The cDNA Libraries were prepared according to Illumina''s TruSeq Stranded Total RNA with Ribo-Zero Gold for Human and a Hiseq 2.500 Illumina platform with 100 bp paired-end reads was used for sequencing
Publication Title
Alterations in Placental Gene Expression of Pregnant Women with Chronic Chagas Disease.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
GENES ASSOCIATED WITH THE CELL CYCLE, LINEAGE COMMITMENT AND IMMUNOMODULATORY POTENTIAL DISCRIMINATE HUMAN POSTNATAL STEM CELLS OF DIFFERENT ORIGIN.
Publication Title
Functional differences between mesenchymal stem cell populations are reflected by their transcriptome.
Sample Metadata Fields
No sample metadata fields
View Samples