Sequencing studies from several model systems have suggested that diverse and abundant small RNAs may derive from tRNA, but the function of these molecules remains undefined. Here we demonstrate that one such tRNA fragment, cloned from human B cells and designated CU1276, in fact possesses the functional characteristics of a microRNA, including a DICER1-dependent biogenesis, physical association with Argonaute proteins, and the ability to repress mRNA transcripts in a sequence-specific manner. The gene expression profiling undertaken for this study was done in order to assay mRNA-level changes in 293T cells upon modulation of CU1276 levels, and thereby to identify direct targets of this sequence. Ultimately, we fully validated the endogenous gene RPA1 as a CU1276 target.
tRNA-derived microRNA modulates proliferation and the DNA damage response and is down-regulated in B cell lymphoma.
Specimen part, Cell line
View SamplesMetastasis depends on the ability of tumor cells to establish a relationship with the newly seeded host tissue that is conducive to their survival and proliferation. Recent evidence suggests that tumor cells regulate their own dissemination by preparing permissive metastatic niches within host tissues. However, the factors that are implicated in rendering tissues permissive for metastatic tumor growth have yet to be fully elucidated. Breast tumors arising during pregnancy display highly aggressive behaviour and early metastatic proclivity, raising the possibility that pregnancy may constitute a physiological condition of permissiveness for tumor dissemination. We show that during murine gestation, both the rate and degree of metastatic tumor growth are enhanced irrespective of tumor type and that decreased natural killer (NK) cell activity is responsible for the observed increase in experimental metastasis. We identify gene expression changes in pregnant mouse lung and liver that bear striking similarity with reported pre-metastatic niche signatures and several of the up-regulated genes are indicative of myeloid-cell infiltration. We provide evidence, that CD11b+ Gr-1+ myeloid-derived suppressor cells accumulate in pregnant mice and exert an inhibitory effect on NK cell activity, thereby enhancing metastatic tumor growth. MDSC have never been evoked in the context of pregnancy and our observations suggest that they may represent a further shared mechanism of immune suppression occurring during gestation and tumor growth.
Myeloid-derived suppressor cells are implicated in regulating permissiveness for tumor metastasis during mouse gestation.
Specimen part
View SamplesBurkitt lymphoma (BL) is a highly aggressive B cell non-Hodgkin lymphoma (B-NHL), which originates from germinal center (GC) B cells and harbors translocations deregulating the MYC oncogene. A comparative analysis of microRNAs (miRNAs) expressed in normal and malignant GC B cells identified miR-28 as significantly down-regulated in BL, as well as in other GC-derived B-NHL. We show that re-expression of miR-28 impairs cell growth and clonogenic properties of BL cells by modulating several targets including MAD2L1, a component of the spindle checkpoint whose down-regulation is essential in mediating miR-28-induced growth-arrest, and BAG1, an activator of the ERK pathway.
MicroRNA 28 controls cell proliferation and is down-regulated in B-cell lymphomas.
Cell line, Treatment, Time
View SamplesThe cytosolic protein Sharpin is as a component of the linear ubiquitin chain assembly complex (LUBAC), which regulates NF-B signaling in response to specific ligands. Its inactivating mutation in Cpdm (chronic proliferative dermatitis mutation) mice causes multi-organ inflammation, yet this phenotype is not transferable into wildtype mice by hematopoietic stem cell transfer. Recent evidence demonstrated that Cpdm mice additionally display low bone mass, but the cellular and molecular causes of this phenotype remained to be established. Here we have applied non-decalcified histology together with cellular and dynamic histomorphometry to perform a thorough skeletal phenotyping of Cpdm mice. We show that Cpdm mice display trabecular and cortical osteopenia, solely explained by impaired bone formation, whereas osteoclastogenesis is unaffected. We additionally found that Cpdm mice display a severe disturbance of articular cartilage integrity in the absence of joint inflammation, supporting the concept that Sharpin-deficiency affects mesenchymal cell differentiation. Consistently, Cpdm mesenchymal cells displayed reduced osteogenic capacitiy ex vivo, yet this defect was not associated with impaired NF-B signaling. A molecular comparison of wildtype and Cpdm bone marrow cell populations further revealed that Cpdm mesenchymal cells produce higher levels of Cxcl5 and lower levels of IL1ra. Collectively, our data demonstrate that skeletal defects of Cpdm mice are not caused by chronic inflammation, but that Sharpin is as a critical regulator of mesenchymal cell differentiation and gene expression. They additionally provide an alternative molecular explanation for the inflammatory phenotype of Cpdm mice and the absence of disease transfer by hematopoetic stem cell transplantation.
Sharpin Controls Osteogenic Differentiation of Mesenchymal Bone Marrow Cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
PRC2 loss amplifies Ras-driven transcription and confers sensitivity to BRD4-based therapies.
Cell line, Treatment
View SamplesThe polycomb repressive complex 2 (PRC2) exerts oncogenic effects in many tumour types1. However, loss-of-function mutations in PRC2 components occur in a subset of haematopoietic malignancies, sug- gesting that this complex plays a dichotomous and poorly understood role in cancer2,3. Here we provide genomic, cellular, and mouse mod- elling data demonstrating that the polycomb group gene SUZ12 func- tions as tumour suppressor in PNS tumours, high-grade gliomas and melanomas by cooperating with mutations in NF1. NF1 encodes a Ras GTPase-activating protein (RasGAP) and its loss drives cancer by activating Ras4. We show that SUZ12 loss potentiates the effects of NF1 mutations by amplifying Ras-driven transcription through effects on chromatin. Importantly, however, SUZ12 inactivation also triggers an epigenetic switch that sensitizes these cancers to bromodomain inhib- itors. Collectively, these studies not only reveal an unexpected con- nection between the PRC2 complex, NF1 and Ras, but also identify a promising epigenetic-based therapeutic strategy that may be exploited for a variety of cancers.
PRC2 loss amplifies Ras-driven transcription and confers sensitivity to BRD4-based therapies.
Cell line, Treatment
View SamplesThis study examines the transcriptional changes invoked by activation of gp130 signaling in different mouse models of B cell lymphomagenesis. In order to study the in vivo effects of aberrant activity of IL-6/IL-6R/gp130-JAK/STAT3 signaling, we designed a transgene that allows conditional expression of L-gp130 by generating a ROSA26 knock-in mouse strain where compound L-gp130 and ZsGreen expression from the CAG promoter is prevented by a loxP- and a rox-flanked stop cassette. Total RNA extracted from purified B cells from young CD19Cre+/- ;L-gp130fl/+ and wildtype control mice was sequenced using unique molecular identifiers (UMI) in a paired end design where read1 corresponds to the cDNA and read2 contains the UMI. Furthermore, aging CD19Cre+/- ;L-gp130fl/+ animals developed tumors located predominantly in mesenteric lymph nodes. Infiltration of CD19;L-gp activated B cells was determined by Flow Cytometry and ZsGreen expression. Total RNA from tumors generally containing >60% ZsGreen+ cells was profiled as described above, for tumors with lower CD19;L-gp activated B cell content FACS was applied. In order to study the effects of activated IL-6/IL-6R/gp130-JAK/STAT3 signaling on Eµ-Myc-driven lymphomagenesis, CD19Cre;L-gp130fl;Eµ-Myc triple transgenic mice were generated and fetal liver hematopoietic stem/progenitor cell (FL-HSPC) grafts were transplanted into lethally irradiated syngeneic mice alongside FL-HSPC from CD19Cre;L-gp130f and Eµ-Myc control mice. Lastly, IL-6/IL-6R/gp130-JAK/STAT3 signaling was activated in the entire hematopoetic system using Vav1Cre resulting in Vav1Cre+/- ;L-gp130fl/+ animals. Independent of the time point of activation during hematopoietic and B cell differentiation, all Cre;L-gp compound mice succumbed to tumors of B cell origin. Overall design: Bulk gene expression data are presented for (i) purified B cells from wildtype control mice (n=6) and young CD19;L-gp mice (n=4), (ii) tumors detected in aging CD19;L-gp mice with a mature (n=11) and plasma cell phenotype (n=6), respectively, (iii) tumors arising in lethally irradiated syngeneic mice after transplantation of fetal liver hematopoietic stem/progenitor cells from CD19;L-gp;Myc (n=9), CD19;L-gp (n=7) and Eµ-Myc (n=9) mice, respectively, and (iv) malignant B cells from Vav1;L-gp mice (n=13).
Activated gp130 signaling selectively targets B cell differentiation to induce mature lymphoma and plasmacytoma.
Specimen part, Subject
View SamplesIn vitro differentiation of embryonic stem cells (ESC) provides models that reproduce in vivo development and cells for therapy. Whether the epigenetic signatures that are crucial for brain development and function and that are sensitive to in vitro culture are similar between native brain tissues and their artificial counterpart generated from ESC is largely unknown. Here, using RNA-seq we have compared the parental origin-dependent expression of imprinted genes (IGs), a model of epigenetic regulation, in cerebral cortex generated either in vivo, or from ESCs using in vitro corticogenesis, a model that reproduces the landmarks of in vivo corticogenesis. For a majority of IGs, the expressed parental alleles were the same for in vivo and in vitro cortex. In most cases, this choice was already set in ESCs and faithfully maintained during the 3 weeks of in vitro corticogenesis. Confirming these findings, methylation, which selects the parental allele to be transcribed, was also largely equivalent between the 2 types of cortex and ESCs. Our results thus indicate that the allele specific expression of imprinted transcripts, a model of epigenetic regulation resulting from a differential methylation of parental genomes, is mostly mimicked in cortical cells derived from ESC. Overall design: We have crossed two strains of mice (B6 and JF1) that display more than 12 million of SNPs (Takada et al., Genome Res. 2013 Aug;23(8):1329-38. doi: 10.1101/gr.156497.113). We have then analyzed allele specific expression transcriptome-wide using RNA-seq on hybrid F1 cortex generated either in vivo or in vitro from ESCs. In addition, we have used 2 different developmental stages of in vivo cortex (E13.5, P0) and three stages in vitro (undiffererentiated ESC, and differentiated into cortex for 12 and 21 days) to measure the dynamics of parental expression. Please note that [1] the same raw data files were used to generate the ''*allele-specific_sense_read_bases_by_gene_withoutContamination.txt'' processed data files. [2] The samples associated with each file are indicated in the file column header (as their GSM accession numbers). [3] The readme.txt file contains the data processing steps, file description.
In Vitro Corticogenesis from Embryonic Stem Cells Recapitulates the In Vivo Epigenetic Control of Imprinted Gene Expression.
No sample metadata fields
View SamplesIdentification of genes that are differentially-expressed in dusp2um287/um287;dusp6um286/um286 mutant embryos compared to wildtype Overall design: Total RNA was extracted from pools of dechrionated, deyolked wildtype and dusp2um287/um287;dusp6um286/um286 embryos at 18hpf using the RNeasy Mini Kit (Qiagen). Three libraries from wildtype embryos and three libraries from dusp2um287/um287;dusp6um286/um286 embryos were then generated from 3mg RNA using the TruSeq Stranded mRNA Library Prep Kit (Illumina). All libraries were analyzed for quality on a bioanalyzer prior to sequencing (Agilent 2100 BioAnalyzer).
A parental requirement for dual-specificity phosphatase 6 in zebrafish.
No sample metadata fields
View SamplesBovine chondrocyte-seeded and mesenchymal stem cell (MSC)-seeded agarose were cultured for 28 days in chemically defined media containing 10 ng/mL TGF-beta3. Chondrogenic differentiated MSCs were compared to chondrocytes at this timepoint and to undifferentiated MSCs harvested at day 0.
Evaluation of the complex transcriptional topography of mesenchymal stem cell chondrogenesis for cartilage tissue engineering.
Specimen part, Subject
View Samples