Cells with slow proliferation kinetics that retain the nuclear label over long time periods – the label-retaining cells (LRCs) – represent multipotent stem cells in a number of adult tissues. Since the identity of liver LRCs (LLRCs) had remained elusive we utilized a genetic approach to reveal LLRCs in normal non-injured livers and characterized their regenerative properties in vivo and in culture. We found that LLRCs were located in biliary vessels and participated in the regeneration of biliary but not hepatocyte injury. In culture experiments the sorted LLRCs displayed an enhanced self-renewal capacity but a unipotent biliary differentiation potential. Transcriptome analysis revealed a unique set of tumorigenesis- and nervous system-related genes upregulated in LLRCs when compared to non-LRC cholangiocytes. We conclude that the LLRCs established during the normal morphogenesis of the liver do not represent a multipotent primitive somatic stem cell population but act as unipotent biliary progenitor cells. Overall design: Transcriptome comparison of label-retaining biliary epithelial cells and non-label-retaining biliary epithelial cells (cells with GFP expression were compared to the cells without GFP). Illumina HiSeq 2000 was used to analyze 8 RNA samples from 4 mice.
A label-retaining but unipotent cell population resides in biliary compartment of mammalian liver.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Biologic pathways associated with relapse in childhood acute lymphoblastic leukemia: a Children's Oncology Group study.
No sample metadata fields
View Samples35 paired samples from initial diagnosis and first marrow relapse. Genes and pathways differentiating diagnosis and relapse were identified. Potential therapeutic targets were also identified.
Biologic pathways associated with relapse in childhood acute lymphoblastic leukemia: a Children's Oncology Group study.
No sample metadata fields
View SamplesAlthough remission rates for metastatic melanoma are generally very poor, some patients can survive for prolonged periods following metastasis. We used gene expression profiling, mitotic index (MI), and quantification of tumor infiltrating leukocytes (TILs) and CD3+ cells in metastatic lesions to search for a molecular basis for this observation and to develop improved methods for predicting patient survival. We identified a group of 266 genes associated with postrecurrence survival. Genes positively associated with survival were predominantly immune response related (e.g., ICOS, CD3d, ZAP70, TRAT1, TARP, GZMK, LCK, CD2, CXCL13, CCL19, CCR7, VCAM1) while genes negatively associated with survival were cell proliferation related (e.g., PDE4D, CDK2, GREF1, NUSAP1, SPC24).
Immune profile and mitotic index of metastatic melanoma lesions enhance clinical staging in predicting patient survival.
Sex, Age
View SamplesIt is widely accepted that a womans lifetime risk of developing breast cancer at menopause is reduced by early full term pregnancy and multiparity. This phenomenon is associated with the development and differentiation of the breast, which ultimately imprints a specific genomic profile in the mammary epithelium. In the present work we demonstrate that this profile represents a permanent signature that could be associated with the breast cancer risk reduction conferred by pregnancy.
Defining the genomic signature of the parous breast.
No sample metadata fields
View SamplesDevelopment of T-cells provides a unique opportunity to study cell-fate determination due to the accessability and the well defined stages of development. In order to understand the genetic programs underlying fetal and adult Tcell fate specification we subjected highly purified fetal and adult T-cell progenitor populations to a genomewide transcriptional analysis. The aim was to identify molecular elements that govern T-cell fate specification as a whole but ultimately to isolate elements that were specific for a given population in a specific developmental window.
Global transcriptional analysis of primitive thymocytes reveals accelerated dynamics of T cell specification in fetal stages.
Sex
View SamplesDesign: Persistent latently infected CD4+ T cells represent a major obstacle to HIV eradication. Histone deacetylase inhibitors (HDACis) are a promising activation therapy in a shock and kill strategy. However, off-target effects of HDACis on host gene expression are poorly understood in primary cells of the immune system. We hypothesized that HDACi-modulated genes would be best identified with a dose response analysis. Methods: Resting primary CD4+ T cells were treated with increasing concentrations (0.34, 1, 3, or 10 M) of the HDACi, suberoylanilide hydroxamic acid (SAHA), for 24 hours and then subjected to microarray gene expression analysis. Genes with dose-correlated expression were identified with a likelihood ratio test using Isogene GX and a subset of these genes with a consistent trend of up or downregulation at each dose of SAHA were identified as dose-responsive. Histone modifications were characterized in promoter regions of the top 6 SAHA dose-responsive genes by RT-qPCR analysis of immunopreciptated chromatin (ChIP). Results: A large number of genes were shown to be up (N=657) or down (N=725) regulated by SAHA in a dose-responsive manner (FDR p-value < 0.05 and fold change |2|). Several of these genes (CTNNAL1, DPEP2, H1F0, IRGM, PHF15, and SELL) are potential in vivo biomarkers of SAHA activity. SAHA dose-responsive gene categories included transcription factors, HIV restriction factors, histone methyltransferases, and host proteins that interact with HIV proteins or the HIV LTR. Pathway analysis suggested net downregulation of T cell activation with increasing SAHA dose. Histone acetylation was not correlated with host expression, but plausible alternative mechanisms for SAHA-modulated expression were identified. Conclusions: Numerous host genes in CD4+ T cells are modulated by SAHA in a dose-responsive manner, including genes that may negatively influence HIV activation from latency. Our study suggests that SAHA influences gene expression through a confluence of several mechanisms, including histone acetylation, histone methylation, and altered expression and activity of transcription factors.
Dose-responsive gene expression in suberoylanilide hydroxamic acid-treated resting CD4+ T cells.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Identification of post-transcriptional regulatory networks during myeloblast-to-monocyte differentiation transition.
Specimen part, Treatment
View SamplesTreatment of leukemia cells with 1,25-dihydroxyvitamin D3 may overcome their differentiation block and lead to the transition from myeloblasts to monocytes. To identify microRNA-mRNA networks relevant for myeloid differentiation, we profiled the expression of mRNAs and microRNAs associated to the low- and high-density ribosomal fractions in leukemic cells and in their differentiated monocytic counterpart. Intersection between mRNAs shifted across the fractions after treatment with putative target genes of modulated microRNAs showed a series of molecular networks relevant for the monocyte cell fate determination
Identification of post-transcriptional regulatory networks during myeloblast-to-monocyte differentiation transition.
Specimen part, Treatment
View SamplesA formidable challenge in neural repair in the adult central nervous system (CNS) is the long distances that regenerating axons often need to travel in order to reconnect with their targets. Thus, a sustained capacity for axon regeneration is critical for achieving functional restoration. Although deletion of either Phosphatase and tensin homolog (PTEN), a negative regulator of mammalian target of rapamycin (mTOR), or suppressor of cytokine signaling 3 (SOCS3), a negative regulator of Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway, in adult retinal ganglion cells (RGCs) individually promoted significant optic nerve regeneration, such regrowth tapered off around two weeks after the crush injury. Remarkably, we now find that simultaneous deletion of both PTEN and SOCS3 enable robust and sustained axon regeneration. We further show that PTEN and SOCS3 regulate two independent pathways that act synergistically to promote enhanced axon regeneration. Gene expression analyses suggest that double deletion not only result in the induction of many growth-related genes, but also allow RGCs to maintain the expression of a repertoire of genes at the physiological level after injury. Our results reveal concurrent activation of mTOR and STAT3 pathways as a key for sustaining long-distance axon regeneration in adult CNS, a crucial step toward functional recovery.
Sustained axon regeneration induced by co-deletion of PTEN and SOCS3.
Specimen part
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