To characterize the molecular origin of primary lymphomas of the central nervous system (PCNSL), 21 PCNSL of immunocompetent patients were investigated by microarray-based gene expression profiling. Comparison of the transcriptional profile of PCNSL with various normal and neoplastic B cell subsets demonstrated PCNSL (i) to display gene expression patterns most closely related to late germinal center B cells, (ii) to display a gene expression profile similar to systemic diffuse large B cell lymphomas (DLBCL), and (iii) to be in part assigned to the activated B cell-like (ABC) or the germinal center B cell-like (GCB) subtype of DLBCL.
Gene expression profiling suggests primary central nervous system lymphomas to be derived from a late germinal center B cell.
No sample metadata fields
View SamplesIn neural stem cells, stimulation of the death receptor CD95 does not trigger apoptosis but resulted in increased stem cell survival and neuronal specification via activation of the Src /PI3K /AKT/mTOR signalling pathway. To further characterize CD95-dependent neural stem cell survival and differentiation we used conventional gene expression profiling combined with translation state array analysis. Mouse neural stem cells grown in neurosphere cultures were stimulated with a trimerized CD95L construct (CD95L-T4) and total as well as polysomal bound RNA was isolated 48 hours after stimulation and analysed by microarrays. CD95L-T4 treatment induced a global increase in ribosome-bound mRNA and protein translation as well as changes on genes involved in neurogenesis, protein synthesis and transcription factors.
The death receptor CD95 activates adult neural stem cells for working memory formation and brain repair.
Sex, Treatment
View SamplesThe Early Growth Response (Egr) family of transcription factors consists of 4 members (Egr1-4) that are expressed in a wide variety of cell types. A large body of evidence point to a role for Egr transcription factors in growth, survival, and differentiation. A major unanswered question is whether Egr transcription factors serve similar functions in diverse cell types by activating a common set of target genes. Signal transduction cascades in neurons and lymphocytes show striking parallels. Activation of either cell type activates the Ras-MAPK pathway and, in parallel, leads to increases in intracellular calcium stimulating the calcineurin-NFAT pathway. In both cell types, the strength of the activation signal affects the cellular outcomes and very strong stimuli lead to cell death. Notably both these pathways converge on the induction of Egr genes. We believe that downstream targets of Egr transcription factors in lymphocytes may also be activated by Egr factors in activated neurons. There is precedence for common target gene activation in these two cell types: apoptosis in both activated T cells and methamphetamine stimulated neurons occurs via FasL induction by NFAT transcription factors. We propose to use developing T lymphocytes (thymocytes) as a model system for discovery of Egr-dependent target genes for several reasons. First, we have observed a prominent survival defect in thymocytes from mice deficient in both Egr1 and Egr3 (1/3 DKO) and a partial differention block in the immature double negative (DN) stage. In addition, thymocytes are an easily manipulatable cell type, and the DN subpopulation affected in 1/3 DKO mice can be isolated to very high purity. We anticipate that 1/3 DKO thymocytes will provide an excellent experimental system that will provide insight into Egr-dependent transcription in neuronal development, activation, and death.
Redundant role for early growth response transcriptional regulators in thymocyte differentiation and survival.
No sample metadata fields
View SamplesIn most embryos, the mid-blastula transition is a complex process featuring maternal RNA degradation, cell cycle pause, zygotic transcriptional activation and morphological changes. The nucleocytoplasmic (N/C) ratio has been proposed to control the multiple events at MBT. To understand the global transcriptional response to the changes of the N/C ratio, we profiled wild type and haploid embryos using cDNA microarrays at three developmental stages.
Coupling of zygotic transcription to mitotic control at the Drosophila mid-blastula transition.
No sample metadata fields
View SamplesKaposis sarcoma-associated hepesvirus (KSHV) encodes four genes with homology to human interferon regulatory factors (IRFs). One of these IRFs, the viral interferon regulatory factor 3 (vIRF-3) is expressed in latently infected PEL cells and required for their continuous proliferation. Moreover, vIRF-3 is known to be involved in modulation of the type I interferon response.
Kaposi's sarcoma-associated herpesvirus viral interferon regulatory factor 3 inhibits gamma interferon and major histocompatibility complex class II expression.
Specimen part, Cell line
View SamplesProtein homeostasis in the endoplasmic reticulum (ER) has recently emerged as a therapeutic target for cancer treatment. Disruption of ER homeostasis results in ER stress, which is a major cause of cell death for cells exposed to the proteasome inhibitor Bortezomib, an anti-cancer drug approved for treatment of multiple myeloma and Mantle cell lymphoma. We recently reported that the ERAD inhibitor Eeyarestatin I (EerI) also disturbs ER homeostasis and has anti-cancer activities resembling that of Bortezomib.
The ERAD inhibitor Eeyarestatin I is a bifunctional compound with a membrane-binding domain and a p97/VCP inhibitory group.
Cell line
View SamplesThe ubiquitin-proteasome system (UPS) has recently emerged as a major target for drug development in cancer therapy. The proteasome inhibitor bortezomib has clinical activity in multiple myeloma and mantle cell lymphoma. Here we report that Eeyarestatin I (EerI), a chemical inhibitor that blocks ER-associated protein degradation (ERAD), has anti-tumor and biologic activities similar to bortezomib, and can synergize with bortezomib. Like bortezomib, EerI-induced cytotoxicity requires the upregulation of the BH3 only pro-apoptotic protein NOXA. We further demonstrate that both EerI and bortezomib activate NOXA via an unanticipated mechanism that requires cooperation between two processes: First, these agents elicit an integrated stress response program at the ER to activate the CREB/ATF transcription factors ATF3 and ATF4. We show that ATF3 and ATF4 form a complex capable of binding to the NOXA promoter, which is required for NOXA activation. Second, EerI and bortezomib also block ubiquitination of histone H2A to relieve its inhibition on NOXA transcription. Our results identify a class of anti-cancer agents that integrate ER stress response with an epigenetic mechanism to induce cell death.
ERAD inhibitors integrate ER stress with an epigenetic mechanism to activate BH3-only protein NOXA in cancer cells.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Plasmacytoid dendritic cells and C1q differentially regulate inflammatory gene induction by lupus immune complexes.
Specimen part, Treatment, Subject
View SamplesThe goal of this study was to determine what genes are up- and down-regulated in response to lupus immune complexes in purified CD14+ monocyte stimulations. Our results have shown that novel genes are induced by immune complexes but the response is less robust when using purified monocytes versus total PBMCs
Plasmacytoid dendritic cells and C1q differentially regulate inflammatory gene induction by lupus immune complexes.
Specimen part, Treatment, Subject
View SamplesWe demonstrate for the first time that the extracellular matrix glycoprotein Tenascin-C regulates the expression of key patterning genes during late embryonic spinal cord development, leading to a timely maturation of gliogenic neural precursor cells. We first show that Tenascin-C is expressed by gliogenic neural precursor cells during late embryonic development. The loss of Tenascin-C leads to a sustained generation and delayed migration of Fibroblast growth factor receptor 3 expressing immature astrocytes in vivo. Furthermore, we could demonstrate an upregulation of Nk2 transcription factor related locus 2 (Nkx2.2) and its downstream target Sulfatase 1 in vivo. A dorsal expansion of Nkx2.2-positive cells within the ventral spinal cord indicates a potential progenitor cell domain shift. Moreover, Sulfatase 1 is known to regulate growth factor signalling by cleaving sulphate residues from heparan sulphate proteoglycans. Consistent with this possibility we observed changes in both Fibroblast growth factor 2 and Epidermal growth factor responsiveness of spinal cord neural precursor cells. Taken together our data clearly show that Tenascin-C promotes the astroglial lineage progression during spinal cord development.
The extracellular matrix molecule tenascin C modulates expression levels and territories of key patterning genes during spinal cord astrocyte specification.
Specimen part
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