Human strabismic extraocular muscles (EOMs) differ from normal EOMs in structural and functional properties, but the gene expression profile of these two types of human EOM has not been examined. Differences in gene expression may inform about causes and effects of the strabismic condition in humans. Our samples are from human strabismic patients undergoing corrective surgery, and from human organ donors with no history of EOM disease.
Differences in gene expression between strabismic and normal human extraocular muscles.
Sex, Specimen part
View SamplesMitochondria control bioenergetics and cell fate decisions, but whether they also participate in extra-organelle signaling is not understood. Here, we show that interference with cyclophilin D (CypD), a mitochondrial matrix protein and apoptosis regulator, causes accelerated cell proliferation and enhanced cell migration and invasion. These responses are associated with global transcriptional changes in CypD-/- cells, predominantly affecting chemokines and their receptors, and resulting in increased activating phosphorylation of Signal Transduction and Activator of Transcription 3 (STAT3). In turn, STAT3 signaling promotes increased proliferation of CypD-/- cells via accelerated S-phase entry and supports Cxcl12-directed paracrine cell motility. Therefore, mitochondria-to-nuclei transcriptional signaling globally affects cell division and motility. As immunosuppressive therapies often target CypD, this pathway may predispose the tissue microenvironment of these patients to oncogenic transformation.
Cyclophilin D extramitochondrial signaling controls cell cycle progression and chemokine-directed cell motility.
Specimen part
View SamplesPrimordial germ cells (PGCs), the embryonic precursors of eggs and sperm, are a unique model for identifying and studying regulatory mechanisms in singly migrating cells. From their time of specification to eventual colonization of the gonad, mouse PGCs traverse through and interact with many different cell types, including epithelial cells and mesenchymal tissues. Work in drosophila and zebrafish have identified many genes and signaling pathways involved in PGC migration, but little is known about this process in mammals.
Discrete somatic niches coordinate proliferation and migration of primordial germ cells via Wnt signaling.
Specimen part
View SamplesThe basic helix-loop-helix (bHLH) transcription factors of the Drosophilas atonal-related superfamily Neurogenin3 (Neurog3) and NeuroD1 promote endocrine differentiation in the gastrointestinal tract. Atonal Homolog 8 (Atoh8/Math6) is a newly identified member of the atonal-related family whose expression is induced by Neurog3 and NeuroD1 in cell culture, indicating a possible role for this gene in the endocrine differentiation program downstream of these two pro-endocrine factors. Intriguingly, available experimental evidence based on a reduced number of genes suggests that Atoh8 may negatively regulate Neurog3-targeting events. In this study, we have analyzed global changes in gene expression profiles upon exogenous expression of Atoh8 alone or in combination with Neurog3 in mouse pancreatic duct (mPAC) cells. These cells activate neuroendocrine-specific gene expression in response to Neurog3 and NeuroD1 and thus serve as an optimal model to evaluate the proendocrine activity of Atoh8. We have compared transcriptional profiles between mPAC cells treated with a recombinant adenovirus expressing Atoh8 (Ad-Atoh8) or a control adenovirus encoding B-galactosidase (Ad-Bgal), and between cells treated with Ad-Neurog3+Ad-Bgal or cells treated with Ad-Neurog3+Ad-Atoh8. The results obtained show that Atoh8 exhibits a very modest transcriptional activity in these cells thus confirming that Atoh8 does not function as a proendocrine gene. Furthermore, our data also confirm the ability of Atoh8 to block Neurog3-dependent transcriptional activation events. However, since repression is only seen for a small subset of Neurog3 gene targets, we discard a general role of Atoh8 as a negative regulator of Neurog3 pro-endocrine activity.
Characterization of the transcriptional activity of the basic helix-loop-helix (bHLH) transcription factor Atoh8.
Cell line, Treatment
View SamplesThe anthracycline, doxorubicin (Dox), is widely used in oncology, but it may it may cause a cardiomyopathy which has dismal prognosis and cannot be effectively prevented. The secretome of multipotent human amniotic fluid-derived stem cells (hAFS) has previously been demonstrated to reduce ischemic cardiac damage. Here, it is shown that the hAFS conditioned medium (hAFS-CM) antagonizes senescence and apoptosis of cardiomyocytes and cardiac progenitor cells, two major features of Dox cardiotoxicity. Mechanistic studies with primary mouse neonatal cardiomyocytes reveal that hAFS-CM inhibition of Dox-elicited senescence and apoptosis is paralleled by decreased DNA damage and is associated with nuclear translocation of NF-kB and upregulation of a set of genes controlled by NF-kB, namely Il6 and Cxcl1, which promote cardiomyocyte survival, and Cyp1b1 and Abcb1, which encode for proteins involved in Dox metabolism and efflux, respectively. The PI3K/Akt signaling cascade, upstream of NF-kB, is potently activated by the hAFS-CM and pre-treatment with a PI3K inhibitor abrogates NF-kB accumulation into the nucleus, modulation of its target genes, and prevention of Dox-initiated senescence and apoptosis in response to the hAFS-CM. This work may lay the ground for the development of a stem cell-based paracrine therapy of chemotherapy-related cardiotoxicity.
The human amniotic fluid stem cell secretome effectively counteracts doxorubicin-induced cardiotoxicity.
Specimen part
View SamplesMurine pancreatic beta cell line MIN6 was growth at two different concentrations of glucose (22,2 and 5,5 mM of glucose), 37C, 5% CO2 and was treated at four different concentrations of human amylin (0, 1, 10 and 20 uM) during three different times (2, 12 and 24 hours)
Impairment of the ubiquitin-proteasome pathway is a downstream endoplasmic reticulum stress response induced by extracellular human islet amyloid polypeptide and contributes to pancreatic beta-cell apoptosis.
No sample metadata fields
View SamplesMounting evidence points to a link between a cancer possessing stem-like properties and a worse prognosis. To understand the biology, a common approach is to integrate network biology with signal processing mechanics. That said, even with the right tools, predicting the risk for a highly susceptible target using only a handful of gene signatures remains very difficult. By compiling the expression profiles of a panel of tumor stem-like cells (TSLCs) originating in different tissues, comparing these to their parental tumor cells (PTCs) and the human embryonic stem cells (hESCs), and integrating network analysis with signaling mechanics, we propose that network topologically-weighted signaling processing measurements under tissue-specific conditions can provide scalable and predicable target identification.
Network biology of tumor stem-like cells identified a regulatory role of CBX5 in lung cancer.
Specimen part
View SamplesPostnatal handling in rodents leads to decreased anxiety-like behavior in adulthood. We used microarrays to look at gene expression differences in the CA1 region of the hippocampus in female mice subjected to postnatal handling compared to controls.
Variation in the large-scale organization of gene expression levels in the hippocampus relates to stable epigenetic variability in behavior.
No sample metadata fields
View SamplesGenetically identical inbred mice exhibit substantial stable individual variability in exploratory behavior. We used microarrays to look at gene expression differences in the hippocampus in female mice separated by stable differences in exploratory behavior
Variation in the large-scale organization of gene expression levels in the hippocampus relates to stable epigenetic variability in behavior.
No sample metadata fields
View SamplesCD24 is a potential oncogene reported to be overexpressed in a large variety of human malignancies. We have shown that CD24 is overexpressed in 90% of colorectal tumors at a fairly early stage in the multistep process of carcinogenesis. Anti-CD24 monoclonal antibodies (mAb) induce a significant growth inhibition in colorectal and pancreatic cancer cell lines that express the protein. This study is designed to investigate further the effects of CD24 down-regulation using mAb or small interfering RNA in vitro and in vivo. Western blot analysis showed that anti-CD24 mAb induced CD24 protein down-regulation through lysosomal degradation. mAb augmented growth inhibition in combination with five classic chemotherapies. Xenograft models in vivo showed that tumor growth was significantly reduced in mAb-treated mice. Similarly, stable growth inhibition of cancer cell lines was achieved by down-regulation of CD24 expression using short hairpin RNA (shRNA). The produced clones proliferated more slowly, reached lower saturation densities, and showed impaired motility. Most importantly, down-regulation of CD24 retarded tumorigenicity of human cancer cell lines in nude mice. Microarray analysis revealed a similar pattern of gene expression alterations when cells were subjected to anti-CD24 mAb or shRNA. Genes in the Ras pathway, mitogenactivated protein kinase, or BCL-2 family and others of oncogenic association were frequently down-regulated. As a putative new oncogene that is overexpressed in gastrointestinal malignancies early in the carcinogenesis process, CD24 is a potential target for early intervention in the prevention and treatment of cancer.
Targeting CD24 for treatment of colorectal and pancreatic cancer by monoclonal antibodies or small interfering RNA.
Specimen part, Cell line
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