Recently, we identified a population of Oct4+Sca-1+Lin-CD45- very small embryonic-like stem-cells (VSELs) in adult tissues. Open chromatin structure of pluripotency genes and genomic imprinting-related epigenetic mechanisms maintain pluripotency and quiescence of VSELs, respectively. However, global transcriptome signature of this rare stem-cell population remains elusive. Here, we demonstrate by genomewide gene-expression analysis with a small number of highly purified murine bone-marrow (BM)-derived VSELs, that Oct4+ VSELs i) express a similar, yet nonidentical, transcriptome as embryonic stem-cells (ESCs), ii) up-regulate cell-cycle checkpoint genes, iii) down-regulate genes involved in protein turnover and mitogenic pathways, and iv) highly express Ezh2, a polycomb group protein.
Global gene expression analysis of very small embryonic-like stem cells reveals that the Ezh2-dependent bivalent domain mechanism contributes to their pluripotent state.
Age, Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Sirt1 Regulates DNA Methylation and Differentiation Potential of Embryonic Stem Cells by Antagonizing Dnmt3l.
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View SamplesDespite education and aggressive treatment, breast cancer (BC) remains a clinical problem. BC cells (BCCs) can migrate early to metastatic sites where they may exist in cellular dormancy for decades. Presently, there are no consensus markers for cancer stem cells (CSCs) that are involved in tumor initiation and progression, and drug resistance. The current designation of CSCs might comprise similar tumor initiating cells, but at different developmental phase. In order to understand these differences, we developed a working hierarchy of BCCs. We initiated the studies in which three BCC subsets were selected based on the relative expressions of the stem cell-linked genes, Octamer4A (Oct4A). The sorted BCCs were subjected to array analyses using Affymetrix gene chip. Hierarchical clustering indicated distinct gene expression among the three subsets. Differential gene expressions of membrane proteins validated three novel genes, TMEM-98, GPR64 and FAT4. These three genes, in combination of known markers for CSCs, CD44, CD24, aldehyde dehydrogenase 1 (ALDH1) and Oct4A, were used to stratify BCCs led to a working hierarchy of BCCs. The validity of the hierarchical BCCs was applied to blood samples from patients, during relapse, and before and after treatment. These studies resulted in the patients grouped with distinct BCCs in the circulation. The relevance of the latter findings are discussed with regards to prediction of treatment response and time of BC relapse. The findings require a larger cohort of patients in a prospective multi-center study. The stratification could be important to understand treatment response, strategies for alternative approaches, and an understanding of the interaction between particular BCC subsets and the tissue microenvironment.
Evaluation of a developmental hierarchy for breast cancer cells to assess risk-based patient selection for targeted treatment.
Specimen part, Cell line
View SamplesStem-cells and transformed cancer cells specifically express a polycomb repressive complex subtype, PRC4 which characteristically contains Sirt1 (Sirtuin-1), a NAD+ dependent class III histone deacetylase (HDAC) and Eed2 isoform as specific members. Analyzing the transcriptiome and methylome analysis of Sirt1 deficient murine ESCs (Sirt1-/- ESC), we demonstrate that these cells repressed specifically on some genomic imprinted and germ-line related genes.
Sirt1 Regulates DNA Methylation and Differentiation Potential of Embryonic Stem Cells by Antagonizing Dnmt3l.
No sample metadata fields
View SamplesTo examine the role of Rb1 in gastrointestinal (GI) tumors we generated mice with an Apc1638N allele, Rbtm2brn floxed alleles, and a villlin-cre transgene (RBVCA). These mice had reduced median survival due to an increase in tumor incidence and multiplicity in the cecum and the proximal colon; they differed from murine intestinal tumors of the Apc1638N type which normally arise solely in the small intestine. We have examined by micro-array analysis three cecal tumors from these mice (probable adenomas), and compared them to three duodenal tumors (probable adenocarcinomas). Expression profiles of duodenal and cecal tumors relative to each other show unique gene subsets up and down regulated. The two tumor types were subsequently shown to differentially regulate distinct sets of genes over expressed in a majority of human colorectal carcinomas.
Loss of Rb1 in the gastrointestinal tract of Apc1638N mice promotes tumors of the cecum and proximal colon.
No sample metadata fields
View SamplesThe NF-B pathway is a critical regulator of the immune system and has been implicated in cellular transformation and tumorigenesis. NF-B response is regulated by the activation state of the IB kinase (IKK) complex and triggered by a wide spectrum of stimuli. We previously reported that NF-B is downstream of Notch1 in T cell acute lymphoblastic leukaemia (T-ALL), however both the mechanisms involving Notch1-induced NF-B activation and the potential importance of NF-B in the maintenance of the disease are unknown. Here we visualize Notch-induced NF-B activation using both human T-ALL cell lines and animal models of this type of leukemia. We show that it is not Notch1 itself but Hes1, a canonical Notch target, the responsible for sustaining IKK activation in T-ALL. Hes1 exerts its effects by a direct transcriptional repression of the deubiquitinating enzyme CYLD, a well-characterized IKK inhibitor. Consistently, CYLD expression is significantly reduced in primary T-ALL leukemias. Finally, we demonstrate that IKK complex inhibition is a promising option for the targeted therapy of T-ALL as suppression of IKK function affected both the survival of human T-ALL cells in vitro and the maintenance of the disease in vivo.
The Notch/Hes1 pathway sustains NF-κB activation through CYLD repression in T cell leukemia.
Specimen part, Cell line
View SamplesInduced and activated regulatory CD4+ Foxp3+ cells compared
Connexin 43 signaling enhances the generation of Foxp3+ regulatory T cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A systems analysis identifies a feedforward inflammatory circuit leading to lethal influenza infection.
Sex, Specimen part
View SamplesTranscriptomic comparison of 5 cell types during lethal and non-lethal influenza infection and further use of these signatures in a top-down systems analysis investigating the relative pathogenic contributions of direct viral damage to lung epithelium vs. dysregulated immunity during lethal influenza infection.
A systems analysis identifies a feedforward inflammatory circuit leading to lethal influenza infection.
Sex, Specimen part
View SamplesMany components of Wnt/-catenin signaling pathway also play critical roles in mammary tumor development. To study the role of Apc in mammary tumorigensis, we introduced conditional Apc mutations specifically into two different mammary epithelial populations using K14-Cre (progenitor) and WAP-cre (lactaing luminal) transgenic mice. Only the K14-cre mediated Apc heterozygosity developed mammary adenocarcinomas demonstrating histological and molecular heterogeneity, suggesting the progenitor cell origin of these tumors. These tumors harbored truncation mutation in a very defined region in the remaining wild-type allele of Apc that would retain some down-regulating activity of -catenin signaling. Our results suggest that not only the epithelial origin but also a certain Apc mutations are selected to achieve a specific level of -catenin signaling optimal for mammary tumor development.
Genetic mechanisms in Apc-mediated mammary tumorigenesis.
No sample metadata fields
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