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1.
Ann Oncol ; 34(5): 477-485, 2023 05.
Article in English | MEDLINE | ID: mdl-36858151

ABSTRACT

BACKGROUND: The first interim analysis of the phase III, randomized, double-blind, placebo-controlled, multinational TITAN study demonstrated improved overall survival (OS) and radiographic progression-free survival (rPFS) with apalutamide added to ongoing androgen deprivation therapy (ADT) in patients with metastatic castration-sensitive prostate cancer. The final analysis confirmed improvement in OS and other long-term outcomes. We evaluated prostate-specific antigen (PSA) kinetics and the association between PSA decline and outcomes in patients with metastatic castration-sensitive prostate cancer from TITAN. PATIENTS AND METHODS: Patients received apalutamide (240 mg/day) or placebo plus ADT (1 : 1). This post hoc exploratory analysis evaluated PSA kinetics and decline in relation to rPFS (22.7 months' follow-up) and OS, time to PSA progression, and time to castration resistance (44.0 months' follow-up) in patients with or without confirmed PSA decline using a landmark analysis, the Kaplan-Meier method, and Cox proportional hazards model. RESULTS: One thousand and fifty-two patients (apalutamide, 525; placebo, 527) were enrolled. Best confirmed PSA declines (≥50% or ≥90% from baseline or to ≤0.2 ng/ml) were achieved at any time during the study in 90%, 73%, and 68% of apalutamide-treated versus 55%, 29%, and 32% of placebo-treated patients, respectively. By 3 months of apalutamide treatment, best deep PSA decline of ≥90% or to ≤0.2 ng/ml occurred in 59% and 51% of apalutamide- and in 13% and 18% of placebo-treated patients, respectively. Achievement of deep PSA decline at landmark 3 months of apalutamide treatment was associated with longer OS [hazard ratio (HR) 0.35; 95% confidence interval (CI) 0.25-0.48), rPFS (HR 0.44; 95% CI 0.30-0.65), time to PSA progression (HR 0.31; 95% CI 0.22-0.44), and time to castration resistance (HR 0.38; 95% CI 0.27-0.52) compared with no decline (P < 0.0001 for all). Similar results were observed at landmark 6 and 12 months of apalutamide treatment. CONCLUSIONS: Apalutamide plus ADT demonstrated a robust (rapid, deep, and durable) PSA decline that was associated with improved clinical outcomes, including long-term survival.


Subject(s)
Prostate-Specific Antigen , Prostatic Neoplasms, Castration-Resistant , Male , Humans , Androgen Antagonists/therapeutic use , Androgens/therapeutic use , Castration
2.
Brain Behav Immun ; 68: 183-196, 2018 02.
Article in English | MEDLINE | ID: mdl-29061364

ABSTRACT

Microglia, like macrophages, can adopt inflammatory and anti-inflammatory phenotypes depending on the stimulus. In macrophages, the evidence indicates that these phenotypes have different metabolic profiles with lipopolysaccharide (LPS)- or interferon-γ (IFNγ)-stimulated inflammatory cells switching to glycolysis as their main source of ATP and interleukin-4 (IL-4)-stimulated cells utilizing oxidative phosphorylation. There is a paucity of information regarding the metabolic signatures of inflammatory and anti-inflammatory microglia. Here, we polarized primary microglia with IFNγ and show that the characteristic increases in tumor necrosis factor-α (TNFα) and nitric oxide synthase 2 (NOS2) were accompanied by increased glycolysis and an increase in the expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase (PFKFB)3, an enzyme that plays a significant role in driving glycolysis. These changes were associated with increased expression of ferritin and retention of iron in microglia. Significantly, retention of iron in microglia increased TNFα expression and also increased glycolysis suggesting that increased intracellular iron concentration may drive the metabolic and/or inflammatory changes. Analysis of microglia prepared from wildtype mice and from transgenic mice that overexpress amyloid precursor protein (APP) and presenilin 1 (PS1; APP/PS1) revealed genotype-related increases in glycolysis, accompanied by increased PFKFB3, and an increase in the expression of ferritin. The data indicate a distinct metabolic signature of inflammatory microglia from APP/PS1 mice that are also distinguishable by their iron handling profiles.


Subject(s)
Microglia/immunology , Microglia/metabolism , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Animals , Brain/metabolism , Disease Models, Animal , Ferritins/metabolism , Glycolysis/physiology , Inflammation/metabolism , Interferon-gamma/metabolism , Interleukin-4/metabolism , Iron/metabolism , Lipopolysaccharides/metabolism , Mice , Mice, Inbred C57BL , Nitric Oxide Synthase Type II/metabolism , Phosphofructokinase-2/metabolism , Presenilin-1/genetics , Presenilin-1/metabolism , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation
3.
Appl Environ Microbiol ; 82(7): 2167-2176, 2016 Jan 29.
Article in English | MEDLINE | ID: mdl-26826233

ABSTRACT

Scombrotoxin fish poisoning (SFP) remains the main contributor of fish poisoning incidents in the United States, despite efforts to control its spread. Psychrotrophic histamine-producing bacteria (HPB) indigenous to scombrotoxin-forming fish may contribute to the incidence of SFP. We examined the gills, skin, and anal vents of yellowfin (n = 3), skipjack (n = 1), and albacore (n = 6) tuna for the presence of indigenous HPB. Thirteen HPB strains were isolated from the anal vent samples from albacore (n = 3) and yellowfin (n = 2) tuna. Four of these isolates were identified as Photobacterium kishitanii and nine isolates as Photobacterium angustum; these isolates produced 560 to 603 and 1,582 to 2,338 ppm histamine in marine broth containing 1% histidine (25°C for 48 h), respectively. The optimum growth temperatures and salt concentrations were 26 to 27°C and 1% salt for P. kishitanii and 30 to 32°C and 2% salt for P. angustum in Luria 70% seawater (LSW-70). The optimum activity of the HDC enzyme was at 15 to 30°C for both species. At 5°C, P. kishitanii and P. angustum had growth rates of 0.1 and 0.2 h(-1), respectively, and the activities of histidine decarboxylase (HDC) enzymes were 71% and 63%, respectively. These results show that indigenous HPB in tuna are capable of growing at elevated and refrigeration temperatures. These findings demonstrate the need to examine the relationships between the rate of histamine production at refrigeration temperatures, seafood shelf life, and regulatory limits.


Subject(s)
Histamine/biosynthesis , Photobacterium/metabolism , Seafood/microbiology , Tuna/microbiology , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Food Contamination , Foodborne Diseases/microbiology , Histamine/toxicity , Histidine Decarboxylase/genetics , Histidine Decarboxylase/metabolism , Marine Toxins/metabolism , Marine Toxins/toxicity , Photobacterium/classification , Photobacterium/enzymology , Photobacterium/genetics , Phylogeny
4.
ESMO Open ; 9(5): 103007, 2024 May.
Article in English | MEDLINE | ID: mdl-38744101

ABSTRACT

BACKGROUND: Understanding stakeholders' perception of cure in prostate cancer (PC) is essential to preparing for effective communication about emerging treatments with curative intent. This study used artificial intelligence (AI) for landscape review and linguistic analysis of definition, context and value of cure among stakeholders in PC. MATERIALS AND METHODS: Subject-matter experts (SMEs) selected cure-related key words using Elicit, a semantic literature search engine, and extracted hits containing the key words from Medline, Sermo and Overton, representing academic researchers, health care providers (HCPs) and policymakers, respectively. NetBase Quid, a social media analytics and natural language processing tool, was used to carry out key word searches in social media (representing the general public). NetBase Quid analysed linguistics of key word-specific hit sets for key word count, geolocation and sentiments. SMEs qualitatively summarised key word-specific insights. Contextual terms frequently occurring with key words were identified and quantified. RESULTS: SMEs identified seven key words applicable to PC (number of acquired hits) across four platforms: Cure (12429), Survivor (6063), Remission (1904), Survivorship (1179), Curative intent (432), No evidence of disease (381) and Complete remission (83). Most commonly used key words were Cure by the general public and HCPs (11815 and 224 hits), Survivorship by academic researchers and Survivor by policymakers (378 hits each). All stakeholders discussed Cure and cure-related key words primarily in early-stage PC and associated them with positive sentiments. All stakeholders defined cure differently but communicated about it in relation to disease measurements (e.g. prostate-specific antigen) or surgery. Stakeholders preferred different terms when discussing cure in PC: Cure (academic researchers), Cure rates (HCPs), Potential cure and Survivor/Survivorship (policymakers) and Cure and Survivor (general public). CONCLUSION: This human-led, AI-assisted large-scale qualitative language-based research revealed that cure was commonly discussed by academic researchers, HCPs, policymakers and the general public, especially in early-stage PC. Stakeholders defined and contextualised cure in their communications differently and associated it with positive value.


Subject(s)
Artificial Intelligence , Prostatic Neoplasms , Social Media , Humans , Male , Prostatic Neoplasms/therapy , Linguistics/methods , Health Policy , Perception , Natural Language Processing
5.
Int J Behav Med ; 19(2): 165-73, 2012 Jun.
Article in English | MEDLINE | ID: mdl-21562781

ABSTRACT

BACKGROUND: Somatisation disorder (SD) has been reported as common in all ethnic groups, but the estimates of its prevalence have varied and the evidence for its associated factors has been inconsistent. PURPOSE: This study seeks to determine the prevalence of SD and its associated factors in multiethnic primary care clinic attenders. METHODS: This cross-sectional study was on clinic attenders aged 18 years and above at three urban primary care clinics in Malaysia. The operational definition of SD was based on ICD-10 criteria for SD for research, frequent attendance, and excluded moderate to severe anxiety and depression. The instruments used were the ICD-10 symptom list, the Hospital Anxiety and Depression Scale, a semi-structured questionnaire, and SF-36. RESULTS: We recruited 1,763 patients (response rate 63.8%). The mean age of respondents was 44.7 ± 15.8 years, 807 (45.8%) were male; there were 35.3% Malay, 30.1% Chinese and 34.6% Indian. SD prevalence was 3.7%; the prevalence in Malay was 5.8%, Indian 3.0% and Chinese 2.1%. Significant associations were found between SD prevalence and ethnicity, family history of alcoholism, blue-collar workers and the physical component summary (PCS) score of SF-36. Multivariate analysis showed that SD predictors were Malay ethnicity (OR 2.7, 95% CI 1.6, 4.6), blue-collar worker (OR 2.0, 95% CI 1.2, 3.5) and impaired PCS score of SF-36 (OR 0.92, 95% CI 0.90, 0.95). CONCLUSION: The prevalence of SD was relatively uncommon with the stringent operational criteria used. SD preponderance in blue-collar workers may be attributable to secondary gain from getting sickness certificates and being paid for time off work.


Subject(s)
Cross-Cultural Comparison , Cultural Characteristics , Somatoform Disorders/ethnology , Adult , Age Factors , Chi-Square Distribution , China/ethnology , Cross-Sectional Studies , Female , Humans , India/ethnology , Malaysia/ethnology , Male , Middle Aged , Prevalence , Primary Health Care/statistics & numerical data , Sex Factors , Socioeconomic Factors , Somatoform Disorders/diagnosis , Statistics, Nonparametric
6.
J Exp Med ; 169(6): 2085-96, 1989 Jun 01.
Article in English | MEDLINE | ID: mdl-2525172

ABSTRACT

We examined the possible role of CD4 molecules during in vivo and in vitro fetal thymic development. Our results show that fetal thymi treated with intact anti-CD4 mAbs fail to generate CD4 single-positive T cells, while the generation of the other phenotypes remains unchanged. Most importantly, the use of F(ab')2 and Fab anti-CD4 mAb gave identical results, i.e., failure to generate CD4+/CD8- T cells, with no effect on the generation of CD4+/CD8+ T cells. Since F(ab')2 and Fab anti-CD4 fail to deplete CD4+/CD8- in adult mice, these results strongly argue that the absence of CD4+/CD8- T cells is not due to depletion, but rather, is caused by a lack of positive selection, attributable to an obstructed CD4-MHC class II interaction. Furthermore, we also observed an increase in TCR/CD3 expression after anti-CD4 (divalent or monovalent) mAb treatment. The TCR/CD3 upregulation occurs in the double-positive population, and may result from CD4 signaling after mAb engagement, or may be a consequence of the blocked CD4-class II interactions. One proposed model argues that the CD3 upregulation occurs in an effort to compensate for the reduction in avidity or signaling that is normally provided by the interaction of the CD4 accessory molecule and its ligand. As a whole, our findings advocate that CD4 molecules play a decisive role in the differentiation of thymocytes.


Subject(s)
Antigens, Differentiation, T-Lymphocyte/physiology , T-Lymphocytes/physiology , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/physiology , Antigens, Differentiation, T-Lymphocyte/immunology , Antigens, Differentiation, T-Lymphocyte/metabolism , CD3 Complex , Cell Differentiation , Female , Fetus , Histocompatibility Antigens Class II/immunology , Immunoglobulin Fab Fragments/physiology , Immunosuppressive Agents/physiology , Mice , Mice, Inbred C57BL , Mice, Nude , Organ Culture Techniques , Pregnancy , Receptors, Antigen, T-Cell/metabolism , T-Lymphocytes/classification , T-Lymphocytes/immunology
7.
Science ; 249(4976): 1558-61, 1990 Sep 28.
Article in English | MEDLINE | ID: mdl-2120773

ABSTRACT

Most immature CD4+CD8+ thymocytes express only a small number of T cell receptor (TCR) molecules on their surface, and the TCR molecules they do express are only marginally capable of transducing intracellular signals. TCR expression and function was not intrinsically low in immature CD4+CD8+ thymocytes, but was found to be actively inhibited by CD4-mediated signals. Indeed, release of CD4+CD8+ thymocytes from CD4-mediated signals resulted in significant increases in both TCR expression and signaling function. These results suggest that, in CD4+CD8+ cells developing in the thymus, increased TCR expression and function requires release from CD4-mediated inhibition.


Subject(s)
Antigens, Differentiation, T-Lymphocyte/immunology , CD4 Antigens/immunology , Receptors, Antigen, T-Cell/physiology , T-Lymphocytes/immunology , Animals , Antibodies, Monoclonal/immunology , CD8 Antigens , Cell Membrane/immunology , Cells, Cultured , Histocompatibility Antigens Class II/immunology , Mice , Mice, Inbred C57BL , Receptors, Antigen, T-Cell/biosynthesis
8.
J Pharmacol Exp Ther ; 325(2): 681-90, 2008 May.
Article in English | MEDLINE | ID: mdl-18287214

ABSTRACT

We have recently proposed the hypothesis that inhibition of the cyclic nucleotide phosphodiesterase (PDE) 10A may represent a new pharmacological approach to the treatment of schizophrenia (Curr Opin Invest Drug 8:54-59, 2007). PDE10A is highly expressed in the medium spiny neurons of the mammalian striatum (Brain Res 985:113-126, 2003; J Histochem Cytochem 54:1205-1213, 2006; Neuroscience 139:597-607, 2006), where the enzyme is hypothesized to regulate both cAMP and cGMP signaling cascades to impact early signal processing in the corticostriatothalamic circuit (Neuropharmacology 51:374-385, 2006; Neuropharmacology 51:386-396, 2006). Our current understanding of the physiological role of PDE10A and the therapeutic utility of PDE10A inhibitors derives in part from studies with papaverine, the only pharmacological tool for this target extensively profiled to date. However, this agent has significant limitations in this regard, namely, relatively poor potency and selectivity and a very short exposure half-life after systemic administration. In the present report, we describe the discovery of a new class of PDE10A inhibitors exemplified by TP-10 (2-{4-[-pyridin-4-yl-1-(2,2,2-trifluoro-ethyl)-1H-pyrazol-3-yl]-phenoxymethyl}-quinoline succinic acid), an agent with greatly improved potency, selectivity, and pharmaceutical properties. These new pharmacological tools enabled studies that provide further evidence that inhibition of PDE10A represents an important new target for the treatment of schizophrenia and related disorders of basal ganglia function.


Subject(s)
Phosphodiesterase Inhibitors/pharmacology , Phosphoric Diester Hydrolases/physiology , Pyrazoles/pharmacology , Quinolines/pharmacology , Schizophrenia/drug therapy , Animals , Behavior, Animal/drug effects , Brain/drug effects , Brain/metabolism , Cyclic AMP/metabolism , Cyclic GMP/metabolism , Dopamine/metabolism , Male , Mice , Mice, Inbred C57BL , Motor Activity/drug effects , Phosphodiesterase Inhibitors/blood , Phosphodiesterase Inhibitors/pharmacokinetics , Phosphoric Diester Hydrolases/genetics , Rats , Rats, Inbred F344 , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/genetics , Reflex, Startle/drug effects , Schizophrenia/metabolism , Schizophrenia/physiopathology
9.
Sci Rep ; 8(1): 2860, 2018 02 12.
Article in English | MEDLINE | ID: mdl-29434252

ABSTRACT

The hot injection synthesis of nanomaterials is a highly diverse and fundamental field of chemical research, which has shown much success in the bottom up approach to nanomaterial design. Here we report a synthetic strategy for the production of anisotropic metal chalcogenide nanomaterials of different compositions and shapes, using an optimised hot injection approach. Its unique advantage compared to other hot injection routes is that it employs one chemical to act as many agents: high boiling point, viscous solvent, reducing agent, and surface coordinating ligand. It has been employed to produce a range of nanomaterials, such as CuS, Bi2S3, Cu2-xSe, FeSe2, and Bi4Se3, among others, with various structures including nanoplates and nanosheets. Overall, this article will highlight the excellent versatility of the method, which can be tuned to produce many different materials and shapes. In addition, due to the nature of the synthesis, 2D nanomaterial products are produced as monolayers without the need for exfoliation; a significant achievement towards future development of these materials.

10.
Neuropharmacology ; 53(1): 113-24, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17559891

ABSTRACT

PDE1B is a calcium-dependent cyclic nucleotide phosphodiesterase that is highly expressed in the striatum. In order to investigate the physiological role of PDE1B in the central nervous system, PDE1B knockout mice (C57BL/6N background) were assessed in behavioral tests and their brains were assayed for monoamine content. In a variety of well-characterized behavioral tasks, including the elevated plus maze (anxiety-like behavior), forced swim test (depression-like behavior), hot plate (nociception) and two cognition models (passive avoidance and acquisition of conditioned avoidance responding), PDE1B knockout mice performed similarly to wild-type mice. PDE1B knockout mice showed increased baseline exploratory activity when compared to wild-type mice. When challenged with amphetamine (AMPH) and methamphetamine (METH), male and female PDE1B knockout mice showed an exaggerated locomotor response. Male PDE1B knockout mice also showed increased locomotor responses to higher doses of phencyclidine (PCP) and MK-801; however, this effect was not consistently observed in female knockout mice. In the striatum, increased dopamine turnover (DOPAC/DA and HVA/DA ratios) was found in both male and female PDE1B knockout mice. Striatal serotonin (5-HT) levels were also decreased in PDE1B knockout mice, although levels of the metabolite, 5HIAA, were unchanged. The present studies demonstrate increased striatal dopamine turnover in PDE1B knockout mice associated with increased baseline motor activity and an exaggerated locomotor response to dopaminergic stimulants such as methamphetamine and amphetamine. These data further support a role for PDE1B in striatal function.


Subject(s)
Behavior, Animal/physiology , Brain Chemistry/genetics , Mice, Knockout , Phosphoric Diester Hydrolases/deficiency , Animals , Avoidance Learning/drug effects , Avoidance Learning/physiology , Behavior, Animal/drug effects , Biogenic Monoamines/metabolism , Brain Chemistry/drug effects , Central Nervous System Stimulants/pharmacology , Chromatography, High Pressure Liquid/methods , Cyclic Nucleotide Phosphodiesterases, Type 1 , Dizocilpine Maleate/pharmacology , Dose-Response Relationship, Drug , Excitatory Amino Acid Antagonists/pharmacology , Female , Male , Maze Learning/drug effects , Maze Learning/physiology , Mice , Mice, Inbred C57BL , Mice, Knockout/genetics , Mice, Knockout/metabolism , Mice, Knockout/physiology , Motor Activity/drug effects , Motor Activity/genetics , Phencyclidine/pharmacology , Sex Factors , Swimming
11.
Mol Cell Biol ; 13(6): 3255-65, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8388535

ABSTRACT

We have used the multifunctional transforming protein, simian virus 40 T antigen, as a probe to study the mechanisms of cell growth regulation in the intact organism. T antigen appears to perturb cell growth, at least in part, by stably interacting with specific cellular proteins that function to maintain normal cell growth properties. Experiments in cultured cells indicate that at least three distinct regions of simian virus 40 T antigen have roles in transformation. Two regions correlate with the binding of known cellular proteins, p53, pRB, and p107. A third activity, located near the amino terminus, has been defined genetically but not biochemically. By targeting expression of wild-type and mutant forms of T antigen to distinct cell types in transgenic mice, we have begun to systematically determine which activities play a role in tumorigenesis of each cell type. In this study, we sought to determine the role of the amino-terminal transformation function with such an analysis of the T-antigen mutant dl1135. This protein, which lacks amino acids 17 to 27, retains the p53-, pRB-, and p107-binding activities yet fails to transform cells in culture. To direct expression in transgenic mice, we used the lymphotropic papovavirus transcriptional signals that are specific for B and T lymphocytes and the choroid plexus epithelium of the brain. We show here that although defective in cell culture, dl1135 specifically induced the development of thymic lymphomas in the mouse. Expression of the protein was routinely observed in B- and T-lymphoid cells, although B-cell abnormalities were not observed. Choroid plexus tumors were observed only infrequently; however, dl1135 was not consistently expressed in this tissue. Within a given transgenic line, the penetrance of T-cell tumorigenesis was 100% but appeared to require secondary events, as judged from the clonal nature of the tumors. These experiments suggest that the amino-terminal region of T antigen has a role in the transformation of certain cell types (such as fibroblasts in culture and B lymphocytes) but is dispensable for the transformation of T lymphocytes.


Subject(s)
Antigens, Polyomavirus Transforming/genetics , Brain Neoplasms/genetics , Cell Transformation, Viral/genetics , Choroid Plexus Neoplasms/genetics , Mutagenesis , Simian virus 40/genetics , Splenic Neoplasms/genetics , Thymus Neoplasms/genetics , Animals , Antibodies, Monoclonal , Antigens, Polyomavirus Transforming/physiology , Base Sequence , Brain Neoplasms/microbiology , Cell Division , Choroid Plexus Neoplasms/microbiology , Flow Cytometry , Lymphocyte Depletion , Mice , Mice, Transgenic , Molecular Sequence Data , Oligodeoxyribonucleotides , Polymerase Chain Reaction , Restriction Mapping , Sequence Deletion , Splenic Neoplasms/microbiology , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Thymus Gland/immunology , Thymus Neoplasms/microbiology
12.
Mol Cell Biol ; 16(4): 1458-70, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8657119

ABSTRACT

To elucidate signal transduction pathways leading to neuronal differentiation, we have investigated a conditionally immortalized cell line from rat hippocampal neurons (H19-7) that express a temperature sensitive simian virus 40 large T antigen. Treatment of H19-7 cells with the differentiating agent basic fibroblast growth factor at 39 degrees C, the nonpermissive temperature for T function, resulted in the activation of c-Raf-1, MEK, and mitogen-activated protein (MAP) kinases (ERK1 and -2). To evaluate the role of Raf-1 in neuronal cell differentiation, we stably transfected H19-7 cells with v-raf or an oncogenic human Raf-1-estrogen receptor fusion gene (deltaRaf-1:ER). deltaRaf-1:ER transfectants in the presence of estradiol for 1 to 2 days expressed a differentiation phenotype only at the nonpermissive temperature. However, extended exposure of the deltaRaf-1:ER transfectants to estradiol or stable expression of the v-raf construct yielded cells that extended processes at the permissive as well as the nonpermissive temperature, suggesting that cells expressing the large T antigen are capable of responding to the Raf differentiation signal. deltaRaf-1:ER, MEK, and MAP kinase activities in the deltaRaf-1:ER cells were elevated constitutively for up to 36 h of estradiol treatment at the permissive temperature. At the nonpermissive temperature, MEK and ERKs were activated to a significantly lesser extent, suggesting that prolonged MAP kinase activation may not be sufficient for differentiation. To test this possibility, H19-7 cells were transfected or microinjected with constitutively activated MEK. The results indicate that prolonged activation of MEK or MAP kinases (ERK1 and -2) is not sufficient for differentiation of H19-7 neuronal cells and raise the possibility that an alternative signaling pathway is required for differentiation of H19-7 cells by Raf.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinases/genetics , Hippocampus/cytology , MAP Kinase Kinase Kinase 1 , Mitogen-Activated Protein Kinases , Neurons/cytology , Protein Serine-Threonine Kinases/genetics , Retroviridae Proteins, Oncogenic/genetics , Animals , Antigens, Polyomavirus Transforming/genetics , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Line , Estradiol/pharmacology , Fibroblast Growth Factor 2/pharmacology , Hippocampus/metabolism , Humans , Mitogen-Activated Protein Kinase 1 , Mitogen-Activated Protein Kinase 3 , Oncogene Proteins v-raf , Phosphorylation , Protein Serine-Threonine Kinases/metabolism , Rats , Receptors, Estrogen/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Retroviridae Proteins, Oncogenic/metabolism , Signal Transduction , Temperature , Transfection
13.
Mol Cell Biol ; 17(5): 2401-12, 1997 May.
Article in English | MEDLINE | ID: mdl-9111309

ABSTRACT

Heparin-binding epidermal growth factor (HB-EGF) gene transcription is rapidly activated in NIH 3T3 cells transformed by oncogenic Ras and Raf and mediates the autocrine activation of the c-Jun N-terminal kinases (JNKs) observed in these cells. A 1.7-kb fragment of the promoter of the murine HB-EGF gene linked to a luciferase reporter was strongly induced following activation of deltaRaf-1:ER, a conditionally active form of oncogenic human Raf-1. Promoter activation by deltaRaf-1:ER required a composite AP-1/Ets transcription factor binding site located between bp -974 and -988 upstream of the translation initiation site. In vivo genomic footprinting indicated that the basal level of occupancy of this composite AP-1/Ets element increased following deltaRaf-1:ER activation. Cotransfection of Ets-2 and p44 mitogen-activated protein (MAP) kinase expression vectors strongly potentiated HB-EGF promoter activation in response to deltaRaf-1:ER. Potentiated activation required both p44 MAP kinase catalytic activity and threonine 72 in the Pointed domain of Ets-2. Biochemical assays demonstrated the ability of the p42 and p44 MAP kinases to phosphorylate Ets-2 on threonine 72. Importantly, in intact cells, the kinetics of phosphorylation of Ets-2 on this residue closely mirror the activation of the p42 and p44 MAP kinases and the observed onset of HB-EGF gene transcription following deltaRaf-1:ER activation. These data firmly establish Ets-2 as a direct target of the Raf-MEK-MAP kinase signaling pathway and strongly implicate Ets-2 in the regulation of HB-EGF gene expression.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinases/metabolism , DNA-Binding Proteins , Epidermal Growth Factor/metabolism , Heparin/metabolism , Protein Serine-Threonine Kinases/pharmacology , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins/pharmacology , Repressor Proteins/metabolism , Trans-Activators/metabolism , Trans-Activators/pharmacology , Transcription Factors , 3T3 Cells , Animals , Base Sequence , DNA Footprinting , Enzyme Activation , Gene Expression Regulation/drug effects , Heparin-binding EGF-like Growth Factor , Humans , Intercellular Signaling Peptides and Proteins , Mice , Molecular Sequence Data , Phosphorylation , Point Mutation , Promoter Regions, Genetic , Proto-Oncogene Protein c-ets-2 , Proto-Oncogene Proteins c-raf , Transcription Factor AP-1/metabolism
14.
Oncogene ; 19(4): 526-36, 2000 Jan 27.
Article in English | MEDLINE | ID: mdl-10698522

ABSTRACT

The Raf/MEK/MAP kinase cascade plays a critical role in transducing growth signals from activated cell surface receptors. Using deltaMEK1:ER, a conditionally-active form of MEK1, we demonstrate the ability of this dual specificity protein kinase to abrogate the cytokine-dependency of the human and murine hematopoietic cells lines TF-1, FDC-P1 and FL5.12. Cytokine-independent cells were obtained from TF-1, FDC-P1 and FL5.12 cells at frequencies of 2.5 x 10(-3), 5 x 10(-5) and 10(-7) respectively, indicating that not all cells expressing deltaMEK1:ER were factor-independent. In general, cells that were converted to a cytokine-independent phenotype displayed a higher level of MAP kinase activity in response to deltaMEK1:ER activation than those that remained cytokine-dependent. deltaME-K1:ER-responsive cells could be maintained long-term in the presence of beta-estradiol as well as the estrogen-receptor antagonist 4-Hydroxy-Tamoxifen and the anti-estrogen ICI 164383. Removal of hormone led to the rapid cessation of cell growth in a manner similar to that observed when cytokine is withdrawn from the parental cells. Treatment of deltaMEKI:ER-responsive cells with a specific and selective inhibitor, PD98059, prevented growth in response to beta-estradiol. GM-CSF mRNA transcripts were detected in the MEK1-responsive cells indicating that the activated deltaMEK1:ER may induce a pathway leading to autocrine proliferation. Treatment of MEK1-responsive cells with an anti-GM-CSF antibody, but not a control antibody, suppressed cell growth. The cell lines described here will be useful for elaborating the ability of the MAP kinase pathway to regulate cell proliferation in hematopoietic cells.


Subject(s)
Autocrine Communication , Cell Transformation, Neoplastic/genetics , Hematopoietic Stem Cells/enzymology , MAP Kinase Signaling System , Mitogen-Activated Protein Kinase Kinases/physiology , Protein Serine-Threonine Kinases/physiology , Animals , Antibodies, Monoclonal/pharmacology , Cell Division/drug effects , Cell Line , Cytokines/pharmacology , Enzyme Activation , Enzyme Induction , Estradiol/pharmacology , Flavonoids/pharmacology , Genes, Synthetic , Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/pathology , Humans , MAP Kinase Kinase 1 , Mice , Mitogen-Activated Protein Kinase Kinases/biosynthesis , Mitogen-Activated Protein Kinase Kinases/genetics , Mutagenesis, Site-Directed , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/genetics , Receptors, Estrogen/genetics , Receptors, Estrogen/metabolism , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/physiology , Tamoxifen/analogs & derivatives , Tamoxifen/pharmacology , Transfection
15.
Trends Pharmacol Sci ; 12(12): 462-7, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1792690

ABSTRACT

The vascular endothelium is a remarkably heterogeneous organ. In addition to well-characterized anatomical diversity in situ, specific differences are increasingly being recognized between surface antigens on endothelial cells from different tissues, including absence of the classic endothelial marker factor VIII-related antigen (von Willebrand factor) from many endothelial cells. Microvascular heterogeneity extends to properties of endothelial cells thought to be involved in tumour angiogenesis and metastasis, such as growth factor responsiveness and expression of cell adhesion molecules. These findings are not only of relevance to the unambiguous identification and characterization of cultured endothelial cells, but, as Roy Bicknell and colleagues discuss, may explain the phenomenon of preferential organ tumour metastasis and provide novel opportunities for antitumour therapy.


Subject(s)
Endothelium, Vascular/physiology , Neoplasm Metastasis/pathology , Organ Specificity/physiology , Cell Adhesion/physiology , Endothelium, Vascular/cytology , Humans , Microcirculation , Neoplastic Cells, Circulating/pathology
16.
J Leukoc Biol ; 70(1): 87-95, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11435490

ABSTRACT

Previously, we showed that NO induces thymocyte apoptosis via a caspase-1-dependent mechanism [(1) ]. In the present study, we investigated the role of heme oxygenase, catalase, bax, and p53 in this process. The NO donor, S-nitroso-N-acetyl penicillamine (SNAP), induced DNA fragmentation in thymocytes in a time- and concentration-dependent way. SNAP (100 microM) induced 50--60% apoptosis; higher doses did not increase the rate of apoptosis significantly. SNAP decreased catalase and heme iron (Fe) levels without affecting superoxide dismutase, glutathione, or total Fe stores in thymocytes. SNAP significantly increased the expression of heme oxygenase 1 (HSP-32), p53, and bax but not bcl-2. Treatment with the heme oxygenase inhibitor, tin protoporphyrin IX inhibited SNAP-induced thymocyte apoptosis. Furthermore, thymocytes from p53 null mice were resistant to NO-induced apoptosis. Our data suggest that NO may induce its cytotoxic effects on thymocytes by modulating heme oxygenase and catalase activity as well as up-regulating pro-apoptotic proteins p53 and bax.


Subject(s)
Apoptosis/drug effects , Nitric Oxide/pharmacology , Thymus Gland/drug effects , Tumor Suppressor Protein p53/physiology , Animals , Apoptosis/physiology , Catalase/metabolism , Coculture Techniques , Enzyme Induction/drug effects , Erythrocytes/cytology , Gene Expression/drug effects , Glutathione/metabolism , Heme/metabolism , Heme Oxygenase (Decyclizing)/biosynthesis , Heme Oxygenase-1 , Iron/metabolism , Membrane Proteins , Mice , Mice, Inbred BALB C , Mice, Knockout , Nitric Oxide Donors/pharmacology , Oxidative Stress/drug effects , Oxidative Stress/physiology , Penicillamine/analogs & derivatives , Penicillamine/pharmacology , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-bcl-2/biosynthesis , Proto-Oncogene Proteins c-bcl-2/genetics , S-Nitroso-N-Acetylpenicillamine , Superoxide Dismutase/metabolism , Thymus Gland/cytology , Thymus Gland/metabolism , Tumor Suppressor Protein p53/biosynthesis , Tumor Suppressor Protein p53/genetics , bcl-2-Associated X Protein
17.
Mar Environ Res ; 59(4): 367-80, 2005 May.
Article in English | MEDLINE | ID: mdl-15589987

ABSTRACT

When Hurricane Iniki struck the Hawaiian Islands in September 1992, it provided a rare opportunity to examine the immediate effects of a hurricane on two intertidal benthic communities off the reefs of O'ahu, Hawai'i. The Niu Beach site contained large, obvious aggregations of the tube building polychaete Diopatra dexiognatha, and the Wailupe Beach site was without obvious tubiculous fauna at the surface. Ten replicate sediment cores were taken before and after the hurricane with a 7.6 cm PVC corer and organisms were identified to family and enumerated. There were no substantial depletions or loss of taxa after the hurricane. Oligochaetes were the most dominant taxa pre-and post-hurricane. The abundance of all dominant polychaete families increased post-hurricane. The three most abundant polychaetes were capitellids and D. dexiognatha (Onuphidae) at Niu Beach and Pygospio muscularis (Spionidae) at Wailupe Beach. We suggest that D. dexiognatha and P. muscularis help stabilize the sediments since they both form dense tube mats while capitellids and oligochaetes are considered highly adaptive surface burrowers that can take advantage of newly disturbed sediments. Overall, there was no substantial effect observed on the intertidal fauna exposed to this severe disturbance. It is suggested here that invertebrate communities in this area are adapted to survive and thrive in high-energy environments and possibly benefit from dense aggregations of tube building polychaetes.


Subject(s)
Disasters , Polychaeta/growth & development , Animals , Classification , Ecosystem , Geologic Sediments , Hawaii , Population Dynamics
18.
Neuropharmacology ; 95: 434-47, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25959066

ABSTRACT

It has been suggested that amphetamine abuse and withdrawal mimics the diverse nature of bipolar disorder symptomatology in humans. Here, we determined if a single paradigm of amphetamine sensitization would be sufficient to produce both manic- and depressive-related behaviors in mice. CD-1 mice were subcutaneously dosed for 5 days with 1.8 mg/kg d-amphetamine or vehicle. On days 6-31 of withdrawal, amphetamine-sensitized (AS) mice were compared to vehicle-treated (VT) mice on a range of behavioral and biochemical endpoints. AS mice demonstrated reliable mania- and depression-related behaviors from day 7 to day 28 of withdrawal. Relative to VT mice, AS mice exhibited long-lasting mania-like hyperactivity following either an acute 30-min restraint stress or a low-dose 1 mg/kg d-amphetamine challenge, which was attenuated by the mood-stabilizers lithium and quetiapine. In absence of any challenge, AS mice showed anhedonia-like decreases in sucrose preference and depression-like impairments in the off-line consolidation of motor memory, as reflected by the lack of spontaneous improvement across days of training on the rotarod. AS mice also demonstrated a functional impairment in nest building, an ethologically-relevant activity of daily living. Western blot analyses revealed a significant increase in methylation of histone 3 at lysine 9 (H3K9), but not lysine 4 (H3K4), in hippocampus of AS mice relative to VT mice. In situ hybridization for the immediate-early gene activity-regulated cytoskeleton-associated protein (Arc) further revealed heightened activation of corticolimbic structures, decreased functional connectivity between frontal cortex and striatum, and increased functional connectivity between the amygdala and hippocampus of AS mice. The effects of amphetamine sensitization were blunted in C57BL/6J mice relative to CD-1 mice. These results show that a single amphetamine sensitization protocol is sufficient to produce behavioral, functional, and biochemical phenotypes in mice that are relevant to bipolar disorder.


Subject(s)
Bipolar Disorder/chemically induced , Cerebral Cortex/drug effects , Dextroamphetamine/administration & dosage , Disease Models, Animal , Limbic System/drug effects , Substance Withdrawal Syndrome/psychology , Anhedonia , Animals , Bipolar Disorder/drug therapy , Bipolar Disorder/physiopathology , Cerebral Cortex/metabolism , Limbic System/metabolism , Lithium Compounds/pharmacology , Male , Memory Consolidation , Mice , Mice, Inbred C57BL , Motor Activity , Nesting Behavior , Neural Pathways/drug effects , Neural Pathways/metabolism , Psychotropic Drugs/pharmacology , Quetiapine Fumarate/pharmacology , Restraint, Physical , Species Specificity , Stress, Psychological/physiopathology , Substance Withdrawal Syndrome/drug therapy , Substance Withdrawal Syndrome/physiopathology
19.
Gene ; 238(2): 301-13, 1999 Oct 01.
Article in English | MEDLINE | ID: mdl-10570958

ABSTRACT

Wnt proteins influence many aspects of embryonic development, and their activity is regulated by several secreted antagonists, including the Xenopus Dickkopf-1 (xDkk-1) protein. xDkk-1 inhibits Wnt activities in Xenopus embryos and may play a role in induction of head structures. Here, we characterize a family of human Dkk-related genes composed of Dkk-1, Dkk-2, Dkk-3, and Dkk-4, together with a unique Dkk-3 related protein termed Soggy (Sgy). hDkks 1-4 contain two distinct cysteine-rich domains in which the positions of 10 cysteine residues are highly conserved between family members. Sgy is a novel secreted protein related to Dkk-3 but which lacks the cysteine-rich domains. Members of the Dkk-related family display unique patterns of mRNA expression in human and mouse tissues, and are secreted when expressed in 293T cells. Furthermore, secreted hDkk-2 and hDkk-4 undergo proteolytic processing which results in cleavage of the second cysteine-rich domain from the full-length protein. Members of the human Dkk-related family differ not only in their structures and expression patterns, but also in their abilities to inhibit Wnt signaling. hDkk-1 and hDkk-4, but not hDkk-2, hDkk-3 or Sgy, suppress Wnt-induced secondary axis induction in Xenopus embryos. hDkk-1 and hDkk-4 do not block axis induction triggered either by Xenopus Dishevelled (Xdsh) or Xenopus Frizzled-8 (Xfz8), both of which function to transduce signals from Wnt ligands. Thus, hDkks 1 and 4 may inhibit Wnt activity by a mechanism upstream of Frizzled. Our findings highlight the structural and functional heterogeneity of human Dkk-related proteins.


Subject(s)
Multigene Family , Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Cell Line , DNA Primers , Female , Humans , Intercellular Signaling Peptides and Proteins , Mice , Molecular Sequence Data , Protein Processing, Post-Translational , Proteins/metabolism , RNA, Messenger/genetics , Sequence Homology, Amino Acid , Xenopus/embryology , Xenopus Proteins
20.
Transplantation ; 59(2): 268-73, 1995 Jan 27.
Article in English | MEDLINE | ID: mdl-7839451

ABSTRACT

One of the principal target organs during graft-versus-host disease (GvHD) is the intestinal epithelium, although the reasons for the preferential involvement of particular organs in this disease are not known. This study analyzed the subset distribution of donor and host lymphocytes in the small intestinal epithelium and the spleen during GvHD in a parent (C57BL/6J) into F1 (C57BL/6JxDBA2/J F1) model. While the donor cell population in the spleen consisted of B and T cells, the donor cell population in the intestine contained only T cells during the course of GvHD. These infiltrating donor cells resembled the host intraepithelial lymphocytes (IELs), which are predominantly CD8+ T cells. This subset distribution of donor cells in the intestinal epithelium was remarkable since they originated from a donor splenocyte population containing few CD8+ lymphocytes. In addition, although the injected donor splenic T cells were virtually all alpha/beta TCR+, several months after GvHD induction more than 30% of the donor cells in the intestine were gamma/delta TCR+, thereby resembling the host IELs not only in their expression of CD4 and CD8, but also in their TCR expression. In contrast, no gamma/delta TCR+ donor cells were detectable in the spleen of GvHD mice. The subset distribution of donor and host IELs remained constant throughout the disease, while in the spleen a decrease of both donor and host B cells and a temporary increase of both donor and host CD8+ cells was observed. These findings demonstrate that in a given target organ during GvHD the disease process affects both donor and host lymphoid populations. In addition the different tissue microenvironments eventually lead to donor cell repopulation with a subset distribution similar to the host natural lymphoid population of the particular target organ.


Subject(s)
Graft vs Host Disease/immunology , Graft vs Host Disease/pathology , Intestine, Small/cytology , Intestine, Small/immunology , Lymphocyte Subsets/immunology , Spleen/cytology , Spleen/immunology , Animals , B-Lymphocyte Subsets/immunology , CD4-CD8 Ratio , CD8-Positive T-Lymphocytes/immunology , Disease Models, Animal , Epithelial Cells , Epithelium/immunology , Intestinal Mucosa/cytology , Intestinal Mucosa/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Phenotype , Receptors, Antigen, T-Cell, gamma-delta/analysis , Receptors, Antigen, T-Cell, gamma-delta/immunology , T-Lymphocyte Subsets/immunology , Tissue Donors
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