The discovery of the first histone demethylase in 2004 (LSD1/KDM1) opened new avenues for the understanding of how histone methylation impacts cellular functions. A great number of histone demethylases have been identified since, which are potentially linked to gene regulation as well as to stem cell self-renewal and differentiation. KDM6A/UTY and KDM6B/JMJD3 are both H3K27me3/2-specific histone demethylases, which are known to play a central role in regulation of posterior development, by regulating HOX gene expression. So far nothing is known about the role of histone lysine demethylases (KDMs) during early hematopoiesis. We are studying the role of KDM6A and KDM6B on self-renewal, global gene expression and on local and global chromatin states in embryonic stem cells (ESCs) and during differentiation. In order to completely abrogate KDM6 demethylase activity in ESCs we employed a specific inhibitor (GSK-J4, Kruidenier et al. 2012). Treatment of ESCs with GSK-J4 had no effect on viability and proliferation . However, ESC differentiation in the presence of GSK-J4 was completely abrogated. In conclusion we show that ESC differentiation is completely blockend in the absence of any H3K27 demethylase activity.
Inhibition of KDM6 activity during murine ESC differentiation induces DNA damage.
Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Early membrane initiated transcriptional effects of estrogens in breast cancer cells: First pharmacological evidence for a novel membrane estrogen receptor element (ERx).
Specimen part, Cell line
View SamplesEstrogens have been reported to activate several processes via membrane binding to either classic estrogen receptors (ERs) or GPR30. We have used either estradiol or BSA-conjugated estradiol in order to initiate membrane-initiated actions and ICI 172,780 (ICI) or G15 to explore ER- and GPR30-related transcription. Our results show that the majority of G15-inhibited transcription is depending on ERs, as it is also inhibited by ICI. However, a small number of transcripts, related to specific actions/pathways is either exclusively inhibited by G15, providing evidence about a specific GPR30 signature, or not inhibited by ICI or G15 suggesting the existence of another, yet unidentified estrogen receptor.
Early membrane initiated transcriptional effects of estrogens in breast cancer cells: First pharmacological evidence for a novel membrane estrogen receptor element (ERx).
Specimen part, Cell line
View SamplesEstrogens have been reported to activate several processes via membrane binding to either classic estrogen receptors (ERs) or GPR30. We have used either estradiol or BSA-conjugated estradiol in order to initiate membrane-initiated actions and ICI 172,780 (ICI) or G15 to explore ER- and GPR30-related transcription. Our results show that the majority of G15-inhibited transcription is depending on ERs, as it is also inhibited by ICI. However, a small number of transcripts, related to specific actions/pathways is either exclusively inhibited by G15, providing evidence about a specific GPR30 signature, or not inhibited by ICI or G15 suggesting the existence of another, yet unidentified estrogen receptor.
Early membrane initiated transcriptional effects of estrogens in breast cancer cells: First pharmacological evidence for a novel membrane estrogen receptor element (ERx).
Specimen part, Cell line
View SamplesEstrogens have been reported to activate several processes via membrane binding to either classic estrogen receptors (ERs) or GPR30. We have used either estradiol or BSA-conjugated estradiol in order to initiate membrane-initiated actions and ICI 172,780 (ICI) or G15 to explore ER- and GPR30-related transcription. Our results show that the majority of G15-inhibited transcription is depending on ERs, as it is also inhibited by ICI. However, a small number of transcripts, related to specific actions/pathways is either exclusively inhibited by G15, providing evidence about a specific GPR30 signature, or not inhibited by ICI or G15 suggesting the existence of another, yet unidentified estrogen receptor.
Early membrane initiated transcriptional effects of estrogens in breast cancer cells: First pharmacological evidence for a novel membrane estrogen receptor element (ERx).
Specimen part, Cell line
View SamplesEstrogens have been reported to activate several processes via membrane binding to either classic estrogen receptors (ERs) or GPR30. We have used either estradiol or BSA-conjugated estradiol in order to initiate membrane-initiated actions and ICI 172,780 (ICI) or G15 to explore ER- and GPR30-related transcription. Our results show that the majority of G15-inhibited transcription is depending on ERs, as it is also inhibited by ICI. However, a small number of transcripts, related to specific actions/pathways is either exclusively inhibited by G15, providing evidence about a specific GPR30 signature, or not inhibited by ICI or G15 suggesting the existence of another, yet unidentified estrogen receptor.
Early membrane initiated transcriptional effects of estrogens in breast cancer cells: First pharmacological evidence for a novel membrane estrogen receptor element (ERx).
Specimen part, Cell line
View SamplesThe role of androgen in breast cancer development is not fully understood although androgen receptors (AR) have been identified in breast cancer clinical samples and cell lines. However the whole spectra of androgen actions cannot be accounted to the classic AR mode of action and the possible existence of a cell surface AR has been suggested. Indeed androgens like all steroids have been reported to trigger membrane initiated signaling activity and exert specific actions. Androgens acting on the membrane can rapidly activate kinase signaling pathways and ultimately could affect gene expression. However, the molecular nature of membrane androgen binding sites represents another major persisting question. In the present study, we investigated early transcriptional effects of testosterone and the impermeable testosterone-BSA conjugate, in two breast cancer cell lines, in an attempt to decipher specific genes modified in each case, providing evidences about specific membrane initiating actions. Our data indicate that the two agents tested affect the expression of several genes. A group of genes were commonly affected while others were uniquely modified by each agent. In MDA-MB-231 cells, that are AR negative, the majority of genes affected by testosterone were also affected by testosterone-BSA indicating a membrane action. Subsequent analysis revealed that the two agents trigger different molecular pathways and cellular/molecular functions, suggestive of a molecular heterogeneity of membrane and intracellular AR. In addition, the phenotypic interactions of membrane-acting androgen with growth factor were verified at the transcriptomic level. Finally an interesting interplay between membrane-acting androgen with inflammation-related molecules, with potential clinical implications was revealed.
Conjugated and non-conjugated androgens differentially modulate specific early gene transcription in breast cancer in a cell-specific manner.
Specimen part, Cell line
View SamplesHIV-1 nucleoside reverse transcriptase inhibitor (NRTI) use is associated with severe adverse events. However, the exact mechanisms behind their toxicity has not been fully understood. Mitochondrial dysfunction after chronic exposure to NRTIs has predominantly been assigned to mitochondrial polymerase-? inhibition by NRTIs. However, an increasing amount of data suggests that this is not the sole mechanism. Many NRTI induced adverse events have been linked to the incurrence of oxidative stress, although the causality of events leading to reactive oxygen species (ROS) production and their role in toxicity is unclear. In this study we show that short-term effects of these drugs, which are rarely discussed in the literature, include direct inhibition of the mitochondrial respiratory chain (MRC), decreased ATP levels and increased ROS production. Collectively these events affect fitness and longevity of C. elegans through mitohormetic signalling events. Furthermore, we demonstrate that these effects can be normalized by addition of the anti-oxidant N-acetylcysteine (NAC), which suggests that ROS likely influence the onset and severity of adverse events upon drug exposure. Overall design: RNA-seq on Caenorhabditis elegans exposed to DMSO, 3''-azido-3''-deoxythymidine (zidovudine or AZT), 2'',3''-didehydro-2'',3''-deoxythymidine (stavudine or d4T), 3''-deoxy-3''-fluorothymidine (alovudine or FLT) or untreated control after 24 or 72 hours of exposure.
Beyond the polymerase-γ theory: Production of ROS as a mode of NRTI-induced mitochondrial toxicity.
Specimen part, Subject
View SamplesMicroRNA-520f regulates EMT, as it activates CDH1 (mRNA) and E-cadherin (protein) expression, and it suppresses tumor cell invasion. We have characterized miR-520f target genes through whole genome transcriptional profiling of miRNA transfected pancreas cancer cells (PANC-1).
miRNA-520f Reverses Epithelial-to-Mesenchymal Transition by Targeting <i>ADAM9</i> and <i>TGFBR2</i>.
Cell line, Treatment
View SamplesHigh VEGFC mRNA expression of AML blasts is related to increased in vitro and in vivo drug resistance. The prognostic significance of VEGFC on long-term outcome and its associated gene expression profiles remain to be defined. We studied the effect of VEGFC on treatment outcome and investigated gene expression profiles associated with VEGFC using microarray data of 525 adult and 100 pediatric AML patients. High VEGFC expression appeared strongly associated with reduced complete remission rate, reduced overall and event-free survival (OS and EFS) in adult AML. Multivariable analysis established high VEGFC as prognostic indicator independent of cytogenetic risk, FLT3-ITD, NPM1, CEBPA, age and WBC. Also in pediatric AML high VEGFC was related to reduced OS. A unique series of differentially expressed genes was identified that distinguished AML with high VEGFC from AML with low VEGFC, i.e., 331 upregulated genes (representative of proliferation, VEGF-receptor activity, signal transduction) and 44 downregulated genes (e.g. related to apoptosis) consistent with a role in enhanced chemoresistance. In conclusion, high VEGFC predicts adverse long-term prognosis and provides prognostic information in addition to well-known prognostic factors.
High VEGFC expression is associated with unique gene expression profiles and predicts adverse prognosis in pediatric and adult acute myeloid leukemia.
Specimen part, Subject
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