The liver is frequently challenged by surgery-induced metabolic overload, viruses, or toxins, which induce the formation of reactive oxygen species. To determine the effect of oxidative stress on liver regeneration and to identify the underlying signalling pathways, we studied liver repair in mice lacking the Nrf2 transcription factor. In these animals, expression of several cytoprotective enzymes was reduced in hepatocytes, resulting in oxidative stress. As a consequence, tissue damage was aggravated, and liver regeneration after partial hepatectomy was delayed.
Impaired liver regeneration in Nrf2 knockout mice: role of ROS-mediated insulin/IGF-1 resistance.
Specimen part
View SamplesEpithelial-mesenchymal transition (EMT) has been linked to cancer progression and metastatic propensity. The 4T1 tumor is a clinically relevant model of spontaneous breast cancer metastasis. Here we characterize 4T1-derived cell lines for EMT, in vitro invasiveness and in vivo metastatic ability. Contrary to expectations, the 67NR cells, which form primary tumors but fail to metastasize, express vimentin and N-cadherin, but not E-cadherin. 4T1 cells, however, express E-cadherin, are highly migratory and invasive, and metastasize to multiple sites. The 66cl4 metastatic cells display mixed epithelial and mesenchymal markers, but are less migratory and invasive than 67NR cells. These findings demonstrate that the metastatic ability of breast cancer cells does not correlate with genotypic and phenotypic properties of EMT per se, and suggest that other processes may govern metastatic capability. Gene expression analysis also has not identified differences in EMT markers, but has identified several candidate genes that may influence metastatic ability.
Epithelial-mesenchymal transition (EMT) is not sufficient for spontaneous murine breast cancer metastasis.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Gene-chip studies of adipogenesis-regulated microRNAs in mouse primary adipocytes and human obesity.
Age, Specimen part
View SamplesVascular smooth muscle cells (VSMC) are important for contraction, blood flow distribution and regulation of blood vessel diameter, but to what extent they contribute to the integrity of blood vessels and blood-brain barrier function is less well understood. In this report, we explored the impact of the progressive loss of VSMC in the Notch3-/- mouse on blood vessel integrity in the central nervous system
Notch3 is necessary for blood vessel integrity in the central nervous system.
Age, Specimen part
View SamplesPrimary murine osteoblasts were isolated form the calvariae of newborn mice. 10 days after the addition of ascorbic acid (50 g/ml) and -glycerophosphate (10 mM), cells were serum-starved over night and then incubated for 6 hours with condtioned medium of MDA-PCa2b cells or conditioned medium of PC-3 cells
Osteolytic prostate cancer cells induce the expression of specific cytokines in bone-forming osteoblasts through a Stat3/5-dependent mechanism.
Specimen part
View SamplesFetal and adult -globin gene expression is tightly regulated during human development. Fetal globin genes are transcriptionally silenced during embryogenesis through the process of hemoglobin switching. Efforts to understand the transcriptional mechanism(s) behind fetal globin silencing have led to novel strategies to derepress fetal globin expression in the adult, which could alleviate symptoms in hereditary b-globin disorders including sickle cell disease (SCD) and -thalassemia. We identified a novel zinc finger protein, pogo transposable element with zinc finger domain (Pogz), expressed in mouse and human hematopoietic stem and progenitor cells, which represses embryonic b-like globin gene expression in mice. Ablation of Pogz expression in adult hematopoietic cells in vivo results in persistence of embryonic b-like globin expression without significantly affecting erythroid development or mouse survival. Elevated embryonic -like globin expression correlates with reduced expression of Bcl11a, a known repressor of embryonic -like globin expression, in Pogz-/- fetal liver cells. Pogz binds to the Bcl11a promoter, and, to erythroid specific intragenic regulatory regions. Importantly, Pogz+/- mice develop normally, but show elevated embryonic b-like globin expression in peripheral blood cells, demonstrating that reducing Pogz levels results in persistence of embryonic b-like globin expression. Finally, knockdown of POGZ in primary human CD34+ hematopoietic stem and progenitor cell derived erythroblasts, reduces BCL11A expression and increases fetal hemoglobin expression. These findings are significant since new therapeutic targets and strategies are needed to treat the increasing global burden of b-globin disorders.
POGZ Is Required for Silencing Mouse Embryonic β-like Hemoglobin and Human Fetal Hemoglobin Expression.
Specimen part
View SamplesUniparental parthenotes are considered an unwanted byproduct of in vitro fertilization. In utero parthenote development is severely compromised by defective organogenesis and in particular by defective cardiogenesis. Although developmentally compromised, apparently pluripotent stem cells can be derived from parthenogenetic blastocysts. Here we hypothesized that nonembryonic parthenogenetic stem cells (PSCs) can be directed toward the cardiac lineage and applied to tissue-engineered heart repair. We first confirmed similar fundamental properties in murine PSCs and embryonic stem cells (ESCs), despite notable differences in genetic (allelic variability) and epigenetic (differential imprinting) characteristics. Haploidentity of major histocompatibility complexes (MHCs) in PSCs is particularly attractive for allogeneic cell-based therapies. Accordingly, we confirmed acceptance of PSCs in MHC-matched allotransplantation. Cardiomyocyte derivation from PSCs and ESCs was equally effective. The use of cardiomyocyte-restricted GFP enabled cell sorting and documentation of advanced structural and functional maturation in vitro and in vivo. This included seamless electrical integration of PSC-derived cardiomyocytes into recipient myocardium. Finally, we enriched cardiomyocytes to facilitate engineering of force-generating myocardium and demonstrated the utility of this technique in enhancing regional myocardial function after myocardial infarction. Collectively, our data demonstrate pluripotency, with unrestricted cardiogenicity in PSCs, and introduce this unique cell type as an attractive source for tissue-engineered heart repair.
Parthenogenetic stem cells for tissue-engineered heart repair.
Specimen part
View SamplesHigh-throughput gene expression profiling has become an important tool for investigating transcriptional activity in a variety of biological samples. To date, the vast majority of these experiments have focused on specific biological processes and perturbations. Here, we profiled gene expression from a diverse array of normal tissues, organs, and cell lines in mice. Keywords: multiple tissues
Expression analysis of G Protein-Coupled Receptors in mouse macrophages.
No sample metadata fields
View SamplesPurpose: We generated extensive transcriptional and proteomic profiles from a Her2-driven mouse model of breast cancer that closely recapitulates human breast cancer. This report makes these data publicly available in raw and processed forms, as a resource to the community. Importantly, we previously made biospecimens from this same mouse model freely available through a sample repository, so researchers can obtain samples to test biological hypotheses without the need of breeding animals and collecting biospecimens.
Proteome and transcriptome profiles of a Her2/Neu-driven mouse model of breast cancer.
Sex, Specimen part
View SamplesNotch1 deficient hair matrix keratinocytes have lower mitotic rates, resulting in smaller follicles with fewer cells. In addition, the ratio of melanocytes to keratinocytes is greatly reduced. Microarray was performed to study downstream mechanism of Notch1-deficiency
Bi-compartmental communication contributes to the opposite proliferative behavior of Notch1-deficient hair follicle and epidermal keratinocytes.
No sample metadata fields
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