Effect of retinoic acid on Nm/23 nucleoside diphosphate kinase and components of cyclic adenosine monophosphate-dependent signalling in human neuroblastorna cell lines

Abstract Bromodomain and extra-terminal domain (BET) proteins, cyclic adenosine monophosphate response element-binding protein (CBP), and the E1A-binding protein of p300 (EP300) are important players in histone acetylation. Preclinical evidence supports the notion that small molecules targeting these proteins individually or in combination can elicit antitumor activity. Here, we characterize the antitumor activity of the pan BET/CBP/EP300 inhibitor NEO2734 and provide insights into its mechanism of action through bromodomain-binding assays, in vitro and in vivo treatments of cancer cell lines, immunoblotting, and transcriptome analyses. In a panel of 60 models derived from different tumor types, NEO2734 exhibited antiproliferative activity in multiple cell lines, with the most potent activity observed in hematologic and prostate cancers. Focusing on lymphoma cell lines, NEO2374 exhibited a pattern of response and transcriptional changes similar to lymphoma cells exposed to either BET or CBP/EP300 inhibitors alone. However, NEO2734 was more potent than single-agent BET or CBP/EP300 inhibitors alone. In conclusion, NEO2734 is a novel antitumor compound that shows preferential activity in lymphomas, leukemias, and prostate cancers.

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Insulin-like growth factor-binding protein-3 production by MCF-7 breast cancer cells: stimulation by retinoic acid and cyclic adenosine monophosphate and differential effects of estradiol.

Endocrinology ◽

10.1210/endo.136.3.7532580 ◽

1995 ◽

Vol 136 (3) ◽

pp. 1219-1226 ◽

Cited By ~ 49

Author(s):

J L Martin ◽

J A Coverley ◽

S T Pattison ◽

R C Baxter

Keyword(s):

Breast Cancer ◽

Retinoic Acid ◽

Growth Factor ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Insulin Like Growth Factor ◽

Factor Binding ◽

Mcf 7

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Isogenic Human Cell Lines for Drug Discovery: Regulation of Target Gene Expression by Engineered Zinc-Finger Protein Transcription Factors

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057104272663 ◽

2005 ◽

Vol 10 (4) ◽

pp. 304-313 ◽

Cited By ~ 11

Author(s):

Pei-Qi Liu ◽

Siyuan Tan ◽

Matthew C. Mendel ◽

Richard J. Murrills ◽

Bheem M. Bhat ◽

...

Keyword(s):

Cell Lines ◽

Zinc Finger ◽

Human Cell ◽

Target Gene ◽

Zinc Finger Protein ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Hek293 Cells ◽

Human Cell Lines ◽

Finger Protein

Isogenic cell lines differing only in the expression of the protein of interest provide the ideal platform for cell-based screening. However, related natural lines differentially expressing the therapeutic target of choice are rare. Here the authors report a strategy for drug screening employing isogenic human cell lines in which the expression of the target protein is regulated by a gene-specific engineered zinc-finger protein (ZFP) transcription factor (TF). To demonstrate this approach, a ZFP TF activator of the human parathyroid hormone receptor 1 (PTHR1) gene was identified and introduced into HEK293 cells (negative for PTHR1). Following induction of ZFP TF expression, this cell line produced functional PTHR1 protein, resulting in a robust and ligand-specific cyclic adenosine monophosphate (cAMP) response. Reciprocally, the natural expression of PTHR1 observed in SAOS2 cells was dramatically reduced by the introduction of the appropriate PTHR1-specific ZFP TF repressor. Moreover, this ZFP-driven PTHR1 repression selectively eliminated the functional cAMP response invoked by known ligands of PTHR1. These data establish ZFP TF–generated isogenic lines as a general approach for the identification of therapeutic agents specific for the target gene of interest.

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GPR18 undergoes a high degree of constitutive trafficking but is unresponsive to N-Arachidonoyl Glycine

PeerJ ◽

10.7717/peerj.1835 ◽

2016 ◽

Vol 4 ◽

pp. e1835 ◽

Cited By ~ 32

Author(s):

David B. Finlay ◽

Wayne R. Joseph ◽

Natasha L. Grimsey ◽

Michelle Glass

Keyword(s):

Cell Lines ◽

Membrane Trafficking ◽

Cannabinoid Receptor ◽

Signal Sequence ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Receptor Expression ◽

Cellular Migration ◽

Orphan Receptor ◽

Cell Surface Expression

The orphan receptor GPR18 has become a research target following the discovery of a putative endogenous agonist, N-arachidonoyl glycine (NAGly). Chemical similarity between NAGly and the endocannabinoid anandamide suggested the hypothesis that GPR18 is a third cannabinoid receptor. GPR18-mediated cellular signalling through inhibition of cyclic adenosine monophosphate (cAMP) and phosphorylation of extracellular signal-regulated kinase (ERK), in addition to physiological consequences such as regulation of cellular migration and proliferation/apoptosis have been described in response to both NAGly and anandamide. However, discordant findings have also been reported. Here we sought to describe the functional consequences of GPR18 activation in heterologously-expressing HEK cells. GPR18 expression was predominantly intracellular in stably transfected cell lines, but moderate cell surface expression could be achieved in transiently transfected cells which also had higher overall expression. Assays were employed to characterise the ability of NAGly or anandamide to inhibit cAMP or induce ERK phosphorylation through GPR18, or induce receptor trafficking. Positive control experiments, which utilised cells expressing hCB1 receptors (hCB1R), were performed to validate assay design and performance. While these functional pathways in GPR18-expressing cells were not modified on treatment with a panel of putative GPR18 ligands, a constitutive phenotype was discovered for this receptor. Our data reveal that GPR18 undergoes rapid constitutive receptor membrane trafficking—several-fold faster than hCB1R, a highly constitutively active receptor. To enhance the likelihood of detecting agonist-mediated receptor signalling responses, we increased GPR18 protein expression (by tagging with a preprolactin signal sequence) and generated a putative constitutively inactive receptor by mutating the hGPR18 gene at amino acid site 108 (alanine to asparagine). This A108N mutant did cause an increase in surface receptor expression (which may argue for reduced constitutive activity), but no ligand-mediated effects were detected. Two glioblastoma multiforme cell lines (which endogenously express GPR18) were assayed for NAGly-induced pERK phosphorylation, with negative results. Despite a lack of ligand-mediated responses in all assays, the constitutive trafficking of GPR18 remains an interesting facet of receptor function and will have consequences for understanding the role of GPR18 in physiology.

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Cyclic adenosine monophosphate protects renal cell lines against amphotericin B toxicity in a PKA-independent manner

Drug and Chemical Toxicology ◽

10.3109/01480545.2015.1012210 ◽

2015 ◽

Vol 39 (1) ◽

pp. 28-34

Author(s):

A. F. Ferreira ◽

F. D. França ◽

J. V. Rossoni ◽

P. H. L. Viana ◽

K. C. M. Moraes ◽

...

Keyword(s):

Amphotericin B ◽

Cell Lines ◽

Renal Cell ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Independent Manner ◽

Renal Cell Lines

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LSP1 modulates the locomotion of monocyte-differentiated U937 cells

Blood ◽

10.1182/blood.v96.3.1100 ◽

2000 ◽

Vol 96 (3) ◽

pp. 1100-1105 ◽

Cited By ~ 8

Author(s):

Yao Li ◽

Qihong Zhang ◽

Rosemary Aaron ◽

Lee Hilliard ◽

Thomas H. Howard

Keyword(s):

Cell Division ◽

Cell Lines ◽

U937 Cell ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Specific Protein ◽

Actin Binding ◽

U937 Cells ◽

Monocytic Differentiation ◽

Entire Cell

Abstract To examine the effect of lymphocyte specific protein 1 (LSP1) on phagocytic cell motility, stable transfection of LSP1-null U937 cell line with an episomal expression vector carrying the LSP1 complementary DNA created lines expressing varied LSP1 levels. Mock transfectants without LSP1 (U937−) and cell lines with LSP1 levels similar to those of monocytes (U937+) or 4-fold those of monocytes (U937++++) express LSP1 as indicated and express other actin-binding proteins at normal levels before or after monocytic induction (MI) with dibutyryl cyclic adenosine monophosphate. The cell lines were compared for rate of growth and cell division and, after monocytic differentiation, were video-tracked to measure locomotion as distance moved in 2 hours and examined for morphologic changes. Rates of cell division and growth were similar for different U937 cell lines at all LSP1 levels. In contrast, mean rate of locomotion (micrometers moved in 2 hours) was slower in MI–U937++++ (7.78 + 1.11μm, n = 3) and MI-U937− (23.89 + 2.78μm, n = 3) than in MI-U937+ cells (50.77 + 4.11μm, n = 3). Compared with MI-U937−, the locomotive histogram (n = 150 cells) of MI-U937+ or MI-U937++++ cells shows all cells move respectively faster or slower as an entire cell population. In LSP1+ U937 phagocytes, high LSP1 levels inhibit some (locomotion) but not all (cytokinesis) cell motile behaviors and cause the formation of surface projections. In contrast, normal LSP1 levels in U937 phagocytes enhance some (locomotion) but not all (cytokinesis) cellular motile behaviors and have no effect on cell morphology. Therefore, LSP1 level has a unique biphasic effect on cellular locomotion. The data suggest LSP1 is an important regulator of phagocyte locomotion.

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All-trans retinoic acid and cyclic adenosine monophosphate cooperate in the expression of leukocyte alkaline phosphatase in acute promyelocytic leukemia cells

Blood ◽

10.1182/blood.v85.12.3619.bloodjournal85123619 ◽

1995 ◽

Vol 85 (12) ◽

pp. 3619-3635 ◽

Cited By ~ 35

Author(s):

M Gianni ◽

M Terao ◽

P Norio ◽

T Barbui ◽

A Rambaldi ◽

...

Keyword(s):

Alkaline Phosphatase ◽

Retinoic Acid ◽

Acute Promyelocytic Leukemia ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Promyelocytic Leukemia ◽

Myelogenous Leukemia ◽

Trans Retinoic Acid ◽

All Trans Retinoic Acid ◽

Leukocyte Alkaline Phosphatase

Treatment of acute promyelocytic leukemia (APL) blasts with cyclic adenosine monophosphate (cAMP) analogs, in combination with all-trans retinoic acid (ATRA), results in the upregulation of the expression of leukocyte alkaline phosphatase (LAP), a marker for the differentiation of the granulocyte. The synergistic interaction between the cyclic nucleotide analogs and the retinoid is not unique to APL cells, as it is observed also in the peripheral granulocytes of chronic myelogenous leukemia (CML) patients. The molecular mechanisms underlying LAP induction were studied in NB4, an immortalized APL cell line. Induction of LAP enzymatic activity is dependent on the time of exposure and on the concentrations of dibutyryl-cAMP or 8-bromo-cAMP and ATRA, two factors that influence the kinetics of appearance of detectable levels of the enzyme. Augmentation of LAP levels by ATRA and cAMP is the result of both transcriptional and early posttranscriptional events and requires de novo protein synthesis. LAP induction correlates with augmentation in the levels of the type I catalytic subunit of cAMP-dependent protein kinase transcript and with granulocytic differentiation. The transcriptional component of the process leading to increased LAP gene expression was reproduced in its main features by transient transfection experiments performed in COS-7 cells using the normal retinoic acid receptor type alpha (RAR-alpha) or the APL-specific aberrant form (PML-RAR) and the upstream promoter of the liver/bone/kidney (L/B/K)-type alkaline phosphatase gene. The promoter is upregulated by treatment with ATRA, and this upregulation is further increased by cAMP analogs.

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