Aberrant signal transduction contributes substantially to leukemogenesis. The Janus kinase 1 (JAK1) gene encodes a cytoplasmic tyrosine kinase that noncovalently associates with a variety of cytokine receptors and plays a nonredundant role in lymphoid cell precursor proliferation, survival, and differentiation. Somatic mutations in JAK1 occur in individuals with acute lymphoblastic leukemia (ALL). JAK1 mutations were more prevalent among adult subjects with the T cell precursor ALL, where they accounted for 18% of cases, and were associated with advanced age at diagnosis, poor response to therapy, and overall prognosis
ALL-associated JAK1 mutations confer hypersensitivity to the antiproliferative effect of type I interferon.
Specimen part
View SamplesStatins and bisphosponates (BPs) are two distinct classes of isoprenoid pathway inhibitors targeting HMG-CoA reductase (upstream enzyme) and Farnesyl-pyrophospate synthase (downstream enzyme) respectively. Here we conducted a comparative study of two representatives of these classes, fluvastatin (Fluva) and Zoledronate (Zol), to assess the differences in their in vivo metastatic potentials and pharmacogenomic profiles. Both drugs, being administered after emergence of detectable metastases, appeared to be potent metastasis inhibitors in MDA-MB-231 breast cancer metastasis model. We observed a reduced number of metastatic sites under Fluva, but not Zol treatment. Combinatorial in vivo treatment by Fluva and Zol showed no synergy for these drugs, as reported earlier on the basis of in vitro studies (Budman DR, Oncology 2006), staying in line with similarity of their transcriptomic profiles. Comparison of Zol and Fluva transcriptomic profiles revealed similar patterns of affected genes (describe involved genes functions) through different kinetics (when treated with IC50 determined for 72h treatment, the majority of changes were observed after 24h incubation with Fluva , and only after 48h incubation with Zol at 72h-IC50 or after 24h treatment with its 3 times higher dose). We demonstrated here that targeting different enzymes of the same pathway neither necessarily leads to distinct changes in gene profiles, nor to synergy for in vivo anti-metastatic potential.
Transcriptome analysis and in vivo activity of fluvastatin versus zoledronic acid in a murine breast cancer metastasis model.
Cell line, Time
View SamplesVascular endothelial growth factor is a multifunctional cytokine playing important roles in angiogenesis, tumor progression and metastasis. Alternative splicing results in the production of several different isoforms of VEGF. We have previously generated human breast cancer cells overexpressing VEGF165 or VEGF189 isoforms (referred to as the V165 and V189 clones, respectively) and showed that VEGF189-transfected cells were less tumorigenic. In this study, we used bioluminescence imaging to analyze the metastasis capacity of breast cancer cell lines (MDA-MB-321) overexpressing VEGF isoforms in nude mice. V165, V189 and control cV clones were transfected with a luciferase plasmid to generate bioluminescent clones (the V165-B, V189-B and cV clones, respectively). These clones were then injected into the left heart ventricle of nude mice.
MDA-MB-231 breast cancer cells overexpressing single VEGF isoforms display distinct colonisation characteristics.
No sample metadata fields
View SamplesTo understand the link between invasion behavior and the steps of metastasis formation, we isolated invasive subpopulations from MDA-MB-231 cells in vitro using matrigel coated boyden chambers. Whole genome transcriptional profiling was used to characterize the expression changes uniquely related to invasive abilities of these cells.
Invading basement membrane matrix is sufficient for MDA-MB-231 breast cancer cells to develop a stable in vivo metastatic phenotype.
Cell line
View SamplesTranscriptome levels of matched patient-derived xenograft (PDX) in vitro-in vivo models. Overall design: Comparison of gene expression levels between matched patient-derived xenograft in vitro-in vivo models.
Generation of matched patient-derived xenograft in vitro-in vivo models using 3D macroporous hydrogels for the study of liver cancer.
Specimen part, Disease, Subject
View SamplesLuminal breast cancers express estrogen (ER) and progesterone (PR) receptors, and respond to endocrine therapies. However, some ER+PR+ tumors display intrinsic or acquired resistance, possibly related to PR. Two PR isoforms, PR-A and PR-B, regulate distinct gene subsets that may differentially influence tumor fate. A high PR-A:PR-B ratio is associated with poor prognosis and tamoxifen resistance. We speculate that excessive PR-A marks tumors that will relapse early. Here we address mechanisms by which PR-A regulate transcription, focusing on SUMOylation. We use receptor mutants and synthetic promoter/reporters to show that SUMOylation deficiency or the deSUMOylase SENP1 enhance transcription by PR-A, independent of the receptors dimerization interface or DNA binding domain. De-SUMOylation exposes the agonist properties of the antiprogestin RU486. Thus, on synthetic promoters, SUMOylation functions as an independent brake on transcription by PR-A. What about PR-A SUMOylation of endogenous human breast cancer genes? To study these, we used gene expression profiling. Surprisingly, PR-A SUMOylation influences progestin target genes differentially, with some upregulated, others downregulated, and others unaffected. Hormone-independent gene regulation is also PR-A SUMOylation dependent. Several SUMOylated genes were analyzed in clinical breast cancer database. In sum, we show that SUMOylation does not simply repress PR-A. Rather, it regulates PR-A activity in a target selective manner including genes associated with poor prognosis, shortened survival, and metastasis.
SUMOylation Regulates Transcription by the Progesterone Receptor A Isoform in a Target Gene Selective Manner.
Specimen part, Treatment
View SamplesPsychological, psychosocial and physical stress are major risk factors, which enhance the development of sporadic late-onset Alzheimer`s disease. The chronic unpredictable mild stress model mimics those risk factors and triggers signs of neurodegeneration and neuropathological features of sporadic AD such as tau hyperphosphorylation and enhanced amyloid beta generation. The study investigated the impact of chronic unpredictable mild stress on signs of neurodegeneration by analyzing hippocampal gene expression with whole genome microarray gene expression profiling.
Inhibition of ACE Retards Tau Hyperphosphorylation and Signs of Neuronal Degeneration in Aged Rats Subjected to Chronic Mild Stress.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
De Novo Epigenetic Programs Inhibit PD-1 Blockade-Mediated T Cell Rejuvenation.
Specimen part, Treatment
View SamplesThe initial segment of the epididymis is vital for male fertility, therefore, it is important to understand the mechanisms that regulate this important region. Deprival of testicular luminal fluid factors/lumicrine factors from epididymis, a subset of cells within the initial segment undergo apoptosis. In this study, microarray analyses was used to examine early changes in the downstream signal transduction pathways following the loss of lumicrine factors, and we discovered the following cascade of events leading to loss of protection and eventual apoptosis. First, mRNA expression of several key components of ERK pathway decreased sharply after 6 hours of loss protection from testicular lumicrine factors. After 12 hours, the levels of mRNA expression of STAT and NF-B pathways components increased, mRNA expression of genes encoding cell cycle inhibitors increased. After 18 hours of loss protection from testicular lumicrine factors, apoptosis was observed in the initial segment. In conclusion, testicular lumicrine factors protect the cells of the initial segment by activating ERK pathway, repressing STAT and NF-B pathways, and preventing a cascade of reactions leading to apoptosis.
Testicular lumicrine factors regulate ERK, STAT, and NFKB pathways in the initial segment of the rat epididymis to prevent apoptosis.
Sex, Specimen part, Time
View SamplesThe pancreatic beta cells are the only cells that can produce insulin in response to prevailing glycemia. The development of beta cells was found to be depending on the activity of a complex genetic network. Overexpression of transcriptional factor MafK in beta cells have resulted in impairment of thier functions and suppressed insulin secretion and increased the severity of beta cell loss resulting in an overt diabetes.
β-Cell-Specific Mafk Overexpression Impairs Pancreatic Endocrine Cell Development.
Specimen part
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