Regulatory T cells (Tregs) expressing the transcription factor Foxp3 have a pivotal role in maintaining immunological self-tolerance1-5; yet, excessive Treg activities suppress anti-tumor immune responses6-8. Compared to resting phenotype Tregs (rTregs) in the secondary lymphoid organs, Tregs in non-lymphoid tissues including solid tumors exhibit an activated Treg (aTreg) phenotype9-11. However, aTreg function and whether its generation can be manipulated to promote tumor immunity without evoking autoimmunity are largely unexplored. Here we show that the transcription factor Foxo1, previously demonstrated to promote Treg suppression of lymphoproliferative diseases12,13, has an unexpected function in inhibiting aTreg-mediated immune tolerance. We found that aTregs turned over at a slower rate than rTregs, but were not locally maintained in tissues. Transcriptome analysis revealed that aTreg differentiation was associated with repression of Foxo1-dependent gene transcription, concomitant with reduced Foxo1 expression, cytoplasmic Foxo1 localization, and enhanced Foxo1 phosphorylation at sites of the Akt kinase. Treg-specific expression of an Akt-insensitive Foxo1 mutant prevented downregulation of lymphoid organ homing molecules, and impeded Treg homing to non-lymphoid organs, causing CD8+ T cell-mediated autoimmune diseases. Compared to Tregs from healthy tissues, tumor-infiltrating Tregs downregulated Foxo1 target genes more substantially. Expression of the Foxo1 mutant at a lower dose was sufficient to deplete tumor-associated Tregs, activate effector CD8+ T cells, and inhibit tumor growth without inflicting autoimmunity. Thus, Foxo1 inactivation is essential for the migration of aTregs that have a crucial function in suppressing CD8+ T cell responses; and the Foxo signaling pathway in Tregs can be titrated to preferentially break tumor immune tolerance. Overall design: Transcriptome of splenic rTreg (CD4+Foxp3+CD62LhiCD44lo) and aTreg (CD4+Foxp3+CD62LhiCD44lo) were compared. Duplicates from biologically independent animials were used.
Graded Foxo1 activity in Treg cells differentiates tumour immunity from spontaneous autoimmunity.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Ets transcription factor GABP controls T cell homeostasis and immunity.
Specimen part
View SamplesEts family transcription factor GA-binding protein (GABP) regulates gene expression in CD4 and CD8 T cells.
Ets transcription factor GABP controls T cell homeostasis and immunity.
Specimen part
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.
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View SamplesTranscript profiling analysis of Hydraulic conductivity of Root 1 (HCR1) mutant compared to wild type (Col-0) using ARABIDOPSIS GENE1.1ST ARRAY STRIP (901793, Affymetrix, Santa Clara, USA).
A Potassium-Dependent Oxygen Sensing Pathway Regulates Plant Root Hydraulics.
Age, Specimen part
View SamplesAnalysis of lung CD11c+ antigen presenting cells (APCs) isolated from wildtype or Mir22-/- mice exposed to nanoparticulate carbon black (nCB) for one month. MiR-22 plays important roles in nCB induced experimental emphysema through regulating APC activation. Results provide insight into the biological role and target genes of miR-22.
The microRNA miR-22 inhibits the histone deacetylase HDAC4 to promote T(H)17 cell-dependent emphysema.
Age, Specimen part
View SamplesRNA-seq analysis was performed between WT and alphaT-cat KO mouse cerebella aiming to discover gene transcripts altered by the loss of alphaT-cat These altered gene transcripts could be associated with several neurologic disease-relevant pathways Overall design: Total RNA extracted of cerebellar tissue (n=3) from the brains of WT ad alphaT-cat KO mice
αT-catenin in restricted brain cell types and its potential connection to autism.
Specimen part, Subject
View SamplesMitogen-activated protein kinase kinase 4 (MKK4) is a dual-specificity kinase activated by environmental stress, cytokines, and peptide growth factors that reportedly can promote or inhibit tumor cell growth and metastasis. Somatic mutations in the gene encoding MKK4 (MAP2K4) have been identified in various human cancers, but the consequences of these mutations on MKK4 function and the biology of tumor cells that have them have not been elucidated. Here we report that, of the eleven mutations within the MAP2K kinase domain described thus far, one had gain-of-function (Q142L) and six had loss-of-function. Three of the loss-of-function mutations are nonsense mutations that produced C-terminally-truncated proteins (I295fs*23, R304*, and W310*) that were highly ubiqitinated and rapidly degraded when introduced into cells, and three are missense mutations in the ATP-binding pocket (N234I), activation loop (S251N), or C-lobe (P326L). We modeled the consequences of MAP2K4 loss-of-function mutations on cells by introducing MKK4 short-hairpin RNA constructs and found that MKK4 depletion enhanced the ability of a weakly tumorigenic murine cancer cell to metastasize when injected into syngeneic mice but had no effect on primary tumor formation. MKK4-depleted cells exhibited an increased capacity to migrate across PET filters and to invade through matrigel but no change in anchorage-dependent or -independent proliferation. Transcriptional profiling of these cells revealed gene expression changes that promote epithelial-to-mesenchymal transition and angiogenesis. We conclude that MKK4 inactivation promoted metastasis but not primary tumor formation. Collectively, these findings implicate loss-of-function MAP2K4 somatic mutations in tumor metastasis and provide one of the few examples of a somatic mutation in cancer cells that exerts a metastasis-specific effect.
Map2k4 functions as a tumor suppressor in lung adenocarcinoma and inhibits tumor cell invasion by decreasing peroxisome proliferator-activated receptor γ2 expression.
Specimen part, Cell line
View SamplesEptstein-Barr Virus, an oncogenic herpesvirus, infects and immortalizes human B cells in culture into indefinitely-proliferating LCLs. We examined the gene expression of primary B cells during the process of infection and growth transformation at the exon level to analyze early and late virus-induced changes in expression and exon usage.
An ATM/Chk2-mediated DNA damage-responsive signaling pathway suppresses Epstein-Barr virus transformation of primary human B cells.
Specimen part
View SamplesRNA-seq analysis of BJ cells overexpressing RasV12 and escaping senescence Overall design: Immortalized BJ-hTERT cells expressing an oncogenic version of Ras under the control of a doxycyclin-inducible promoter were grown for 60 days in the presence of Dox to induce oncogene-induced senescence (OIS). Three individual clones escaping senescence were isolated and were analyzed by RNA-seq.
Overexpression of Claspin and Timeless protects cancer cells from replication stress in a checkpoint-independent manner.
Specimen part, Subject
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