The accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) results in the condition called ER stress which induces the unfolded protein response (UPR) which is a complex cellular process that includes changes in expression of many genes. Failure to restore homeostasis in the ER is associated with human diseases. To identify the underlying changes in gene expression in response to ER stress, we induced ER stress in human B-cells and then measured gene expression at 10 time-points. We followed up those results by studying cells from 60 unrelated people. We rediscovered genes that were known to play a role in ER stress response and uncovered several thousand genes that are not known to be involved. Two of these are VLDLR and INHBE which showed significant increase in expression following ER stress in B-cells and
Gene expression and genetic variation in response to endoplasmic reticulum stress in human cells.
Cell line, Subject, Time
View SamplesThe causative role of activated Hedgehog signaling in liver fibrosis was investigated in vivo.
Hepatic expression of Sonic Hedgehog induces liver fibrosis and promotes hepatocarcinogenesis in a transgenic mouse model.
Sex, Specimen part
View SamplesThe goal of this experiment was to investigate the molecular mechanism of how Set-beta regulates neurite growth. Set-betas subcellular localization is regulated by posttranslational modifications. We found that Set-beta suppresses neurite growth of purified postnatal rat retinal ganglion cell (RGC) primary neurons when it is overexpressed in the nucleus, whereas recruiting Set-beta to cellular membrane by fusing myr-tag to its N-terminus promotes neurite growth. Here, we transfected purified by immunopanning postnatal rat RGC with wild-type Set-beta which localizes to the nucleus, myr-Set-beta which is recruited to cellular membranes, and mCherry control, and analyzed with microarrays Set-betas subcellular localization-dependent effects on gene expression. We found that wild-type Set- regulated expression of significantly more genes than myr-Set-, consistent with wild-type Set-s nuclear localization and previously described roles in regulating transcription. These data reveal potential downstream gene effectors regulating neurite growth, and specific candidate genes could be validated and tested in future experiments.
Regulating Set-β's Subcellular Localization Toggles Its Function between Inhibiting and Promoting Axon Growth and Regeneration.
Specimen part
View SamplesAnalysis of rapamycin effects on white adipose tissue at gene expression level. The hypothesis tested in the present study was that rapamycin could modify immune cell composition and inflammatory state of the adipose tissue of obese mice.
Beneficial metabolic effects of rapamycin are associated with enhanced regulatory cells in diet-induced obese mice.
Age, Specimen part
View SamplesTristetraprolin (TTP, encoded by Zfp36) regulates the mRNA stability of several important cytokines. Due to the critical role of this RNA-binding protein in the control of inflammation, TTP deficiency leads to the spontaneous development of a complex inflammatory syndrome. So far, this phenotype has been largely attributed to dysregulated production of TNF and IL-23 by myeloid cells such as macrophages or dendritic cells. Here, we generated mice with conditional deletion of TTP in keratinocytes. These mice developed exacerbated inflammation in the imiquimod-induced psoriasis model. Furthermore, these mice progressively developed a spontaneous pathology with systemic inflammation, psoriatic-like skin lesions and dactylitis. Finally, we provide evidence that keratinocyte-derived TNF productin drives the different pathological features. In summary, these findings expand current views on the initiation of psoriasis and related arthritis by revealing the keratinocyte-intrinsic role of TTP.
Tristetraprolin expression by keratinocytes controls local and systemic inflammation.
Specimen part, Treatment
View SamplesA "Cartes d'Identite des Tumeurs" (CIT) project from the french Ligue Nationale Contre le Cancer (<a href="http://cit.ligue-cancer.net" target="_blank">http://cit.ligue-cancer.net</a>). 104 samples; Affymetrix U133A micro-arrays.<br></br> <br></br> Ninety two patients with T-ALL were diagnosed and treated at Saint-Louis hospital, Paris. Seven patients were studied at diagnosis and relapse (total 99 T-ALL samples). There were 56 children (median age 9 years old; range 1 to 16), and 36 adults (median age 27; range 17 to 66). Informed consent was obtained from the patients and/or relatives. T-ALL diagnosis was based on morphological and immunophenotypical criteria using flow cytometry and an extended monoclonal antibody panel.<br></br> <br></br> Using a combination of molecular cytogenetic and large-scale expression analysis in human T-ALL, we identified and characterized a new recurrent chromosomal translocation, targeting the major homeobox gene cluster HOXA and the TCRB locus. Specific quantitative PCR analysis showed that the expression of the whole HOXA gene cluster was dramatically dysregulated in the HOXA-rearranged cases, and also in MLL and CALM-AF10-related T-ALL cases, strongly suggesting that HOXA genes are oncogenic in these leukemias. Inclusion of HOXA-translocated cases in a general molecular portrait of 92 T-ALL based on large-scale expression analysis shows that this rearrangement defines a new homogeneous subgroup, which shares common biological networks with the TLX1 and TLX3-related cases. Since T-ALLs derive from T-cell progenitors, expression profiles of the distinct T-ALL subgroups were analyzed with respect to those of normal human thymic sub-populations. Inappropriate utilization or perturbation of specific molecular networks involved in thymic differentiation was detected. Moreover, we found a significant association between T-ALL oncogenic subgroups and ectopic expression of a limited set of genes, including several developmental genes, namely HOXA, TLX1, TLX3, NKX3-1, SIX6 and TFAP2C. These data strongly support the view that the abnormal expression of developmental genes, including the prototypical homeobox genes HOXA, is critical in T-ALL oncogenesis.<br></br> <br></br> Project Leader: <br></br> FranC'ois Sigaux<br></br> Institut Universitaire d'Hematologie<br></br> Hopital Saint Louis, Paris, France<br></br> <br></br> Data submission:<br></br>Fabien Petel
HOXA genes are included in genetic and biologic networks defining human acute T-cell leukemia (T-ALL).
Sex, Age, Specimen part, Disease, Disease stage, Subject
View SamplesPrevious results suggest that Bmh might inhibit the activity of the transcription factor Adr1 after binding to Adr1-dependent promoters. In a strain lacking the two major histone deacetylases, Hda1 and Rpd3 (hdac), Adr1 is bound to its target promoters recruiting what appears to be an inactive RNA ploymerase II preinitiation complex (PIC). To determine whether Bmh activity inhibits this inactive PIC and the generality of this effect on glucose-repressed gene expression, the mRNA profiles of wild type, bmh mutant, hdac mutant, and bmh hdac mutant cells grown in high glucose medium were compared.
14-3-3 (Bmh) proteins regulate combinatorial transcription following RNA polymerase II recruitment by binding at Adr1-dependent promoters in Saccharomyces cerevisiae.
No sample metadata fields
View SamplesGene signature determination of the effect of a new bromodomain inhibitor among a representative set of leukemic cell lines
BET inhibitor OTX015 targets BRD2 and BRD4 and decreases c-MYC in acute leukemia cells.
Cell line, Compound
View SamplessiRNA-mediated inhibition compared to untreated cells and cells transfected with nonsense siRNA.
Yes-associated protein up-regulates Jagged-1 and activates the Notch pathway in human hepatocellular carcinoma.
Cell line, Treatment
View SamplesAcute myeloid leukemia (AML) is a heterogeneous group of malignancies which may be sensitive to the natural killer (NK) cell anti-tumor response. However, NK cells are frequently defective in AML. Here, we found in an exploratory cohort (n = 46) that NK-cell status at diagnosis of AML separated patients in two groups with a different clinical outcome. Patients with a deficient NK-cell profile, including reduced expression of some activating NK receptors (e.g. DNAM-1, NKp46 and NKG2D) and decreased IFN-g production, had a significantly higher risk of relapse (P = 0.03) independently of cytogenetic classification in multivariate analysis. Patients with defective NK cells showed a profound gene expression decrease in AML blasts for cytokine and chemokine signaling (e.g. IL15, IFNGR1, IFNGR2, CXCR4), antigen processing (e.g. HLA-DRA, HLA-DRB1, CD74) and adhesion molecule pathways (e.g. PVR, ICAM1). A set of 388 leukemic classifier genes defined in the exploratory cohort was independently validated in a multicentric cohort of 194 AML patients. In total, these data evidenced the interplay between NK-cells and AML blasts at diagnosis allowing an immune-based stratification of AML patients independently of clinical classifications.
Defective NK Cells in Acute Myeloid Leukemia Patients at Diagnosis Are Associated with Blast Transcriptional Signatures of Immune Evasion.
Disease, Subject
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