Luminal 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 SamplesSomatic mutations in calreticulin (CALR) are present in approximately 40% of patients with myeloproliferative neoplasms (MPN). However, the mechanism by which mutant CALR is oncogenic is unknown. Here, we demonstrate that a megakaryocytic-specific MPN phenotype is induced when mutant CALR is over-expressed in mice and that the thrombopoietin receptor, MPL is required for mutant CALR driven transformation. Whole transcriptome analysis reveals enrichment of STAT signatures in mutant CALR transformed cells and JAK2 inhibitor treatment abrogates STAT activation. Employing extensive mutagenesis-based structure-function analysis we demonstrate that the positively charged amino acids within the mutant CALR C-terminus are required for cellular transformation through facilitating physical interaction between mutant CALR and MPL. Together, our findings elucidate a novel mechanism of cancer pathogenesis. Overall design: Transcriptomes derived from BA/F3-MPL cells transformed with human wild-type CALR, human mutant CALR 52bp del, or Empty vector, at time zero (t0) and 24 hours (t24) after IL3-withdrawal culture were generated by deep sequencing, two replicas, by HiSeq2000.
Mutant Calreticulin Requires Both Its Mutant C-terminus and the Thrombopoietin Receptor for Oncogenic Transformation.
Cell line, Subject
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 SamplesGata2, a zinc finger TF, is essential for the generation and survival of HSCs in the embryo and has been implicated in the pathogenesis of AML, yet the requirement for Gata2 in adult HSCs and LSCs remains unclear. Using a conditional mouse model where Gata2 was deleted specifically in hematopoietic cells, we show that knockout of Gata2 leads to a rapid and complete cell-autonomous loss of adult HSCs. In Meis1a/Hoxa9 driven AML, deletion of Gata2 impedes maintenance and self-renewal of LSCs. We then performed RNA-seq from sorted control and Gata2 KO LSCs (CD45.2+ c-Kit+) after pIpC treatment in transplanted mice. Overall design: Wild Type and Gata2-/- Meis1a/Hoxa9 LSCs were harvested from mice 24 days after pIpC administration
Gata2 as a Crucial Regulator of Stem Cells in Adult Hematopoiesis and Acute Myeloid Leukemia.
Cell line, Subject
View SamplesGata2, a zinc finger TF, is essential for the generation and survival of HSCs in the embryo and has been implicated in the pathogenesis of AML, yet the requirement for Gata2 in adult HSCs and LSCs remains unclear. Using a conditional mouse model where Gata2 was deleted specifically in hematopoietic cells, we show that knockout of Gata2 leads to a rapid and complete cell-autonomous loss of adult HSCs. We then performed RNA-seq in sorted HSCs (LSK CD48- CD150+) from control and Gata2+/fl;Vav-iCre+ 8-to-10-week old mice. Overall design: Wild Type and Gata2+/- HSCs were harvested from 8-to-10-week old mice
Gata2 as a Crucial Regulator of Stem Cells in Adult Hematopoiesis and Acute Myeloid Leukemia.
Cell line, Subject
View SamplesGene expression data indicate an early up-regulation of inflammatory and fibrotic remodeling pathways in DSC2 transgenic mice vs. non-transgenic control mice. The mice were analyzed at the age of 3.5 and 13 weeks.
Transgenic mice overexpressing desmocollin-2 (DSC2) develop cardiomyopathy associated with myocardial inflammation and fibrotic remodeling.
Age, Specimen part
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 SamplesAberrant 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 SamplesAbstract: Cellular senescence, an integral component of aging and cancer, arises in response to diverse triggers, including telomere attrition, macromolecular damage, and signaling from activated oncogenes. At present, senescent cells are identified by the combined presence of multiple traits, such as senescence-associated protein expression and secretion, DNA damage, and ß-galactosidase activity; unfortunately, these traits are neither exclusively nor universally present in senescent cells. To identify robust shared markers of senescence, we have performed RNA-sequencing analysis across 8 diverse models of senescence triggered in human diploid fibroblasts (WI-38, IMR-90) and endothelial cells (HUVEC, HAEC) by replicative exhaustion, exposure to ionizing radiation or doxorubicin, and expression of the oncogene HRASG12V. The intersection of the altered transcriptomes revealed 47 RNAs consistently elevated and 26 RNAs consistently reduced across all senescence models, including many protein-coding mRNAs and some long noncoding RNAs. We propose that these shared transcriptome profiles will enable the identification of senescent cells in vivo, the investigation of their roles in aging and malignancy, and the development of strategies to target senescent cells therapeutically. Overall design: Transcriptomic analysis of various cell line models of senescence and their respective controls
Transcriptome signature of cellular senescence.
Specimen part, Cell line, Treatment, Subject
View SamplesInterleukin-6 (IL-6) is a proinflammatory cytokine that exerts a wide range of cellular, physiological and pathophysiological responses. Pyrrolidine dithiocarbamate (PDTC) antagonizes the cellular responsiveness to IL-6 through impairment in STAT3 activation and downstream signaling. Here, a transcriptional profiling was conducted as a basis for understanding the biological properties of PDTC in human HepG2 hepatocarcinoma cells. A global comparison of mRNA identified a highly significant difference of dysregulated gene expression transduced by PDTC versus IL-6 in HepG2 cells. Through an unbiased pathway analysis method, we have uncovered the mammalian target of rapamycin (mTOR) pathway together with rapid and dynamic alterations in REDD1 (regulated in development and DNA damage response 1) expression as one of the underlying molecular mechanisms responsible for IL-6 resistance to PDTC. Quantitative PCR and Western blot analyses validated the microarray data by showing the reciprocal pattern of REDD1 expression and subsequent mTOR inhibition after stimulation with PDTC relative to IL-6.
Impact of pyrrolidine dithiocarbamate and interleukin-6 on mammalian target of rapamycin complex 1 regulation and global protein translation.
Cell line
View Samples