1
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Oh ET, Kim HG, Kim CH, Lee J, Kim C, Lee JS, Cho Y, Park HJ. NQO1 regulates cell cycle progression at the G2/M phase. Theranostics 2023; 13:873-895. [PMID: 36793872 PMCID: PMC9925316 DOI: 10.7150/thno.77444] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 12/26/2022] [Indexed: 01/11/2023] Open
Abstract
Rationale: Overexpression of NAD(P)H:quinone oxidoreductase 1 (NQO1) is associated with tumor cell proliferation and growth in several human cancer types. However, the molecular mechanisms underlying the activity of NQO1 in cell cycle progression are currently unclear. Here, we report a novel function of NQO1 in modulation of the cell cycle regulator, cyclin-dependent kinase subunit-1 (CKS1), at the G2/M phase through effects on the stability of c‑Fos. Methods: The roles of the NQO1/c-Fos/CKS1 signaling pathway in cell cycle progression were analyzed in cancer cells using synchronization of the cell cycle and flow cytometry. The mechanisms underlying NQO1/c-Fos/CKS1-mediated regulation of cell cycle progression in cancer cells were studied using siRNA approaches, overexpression systems, reporter assays, co-immunoprecipitation, pull-down assays, microarray analysis, and CDK1 kinase assays. In addition, publicly available data sets and immunohistochemistry were used to investigate the correlation between NQO1 expression levels and clinicopathological features in cancer patients. Results: Our results suggest that NQO1 directly interacts with the unstructured DNA-binding domain of c-Fos, which has been implicated in cancer proliferation, differentiation, and development as well as patient survival, and inhibits its proteasome-mediated degradation, thereby inducing CKS1 expression and regulation of cell cycle progression at the G2/M phase. Notably, a NQO1 deficiency in human cancer cell lines led to suppression of c-Fos-mediated CKS1 expression and cell cycle progression. Consistent with this, high NQO1 expression was correlated with increased CKS1 and poor prognosis in cancer patients. Conclusions: Collectively, our results support a novel regulatory role of NQO1 in the mechanism of cell cycle progression at the G2/M phase in cancer through effects on c‑Fos/CKS1 signaling.
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Affiliation(s)
- Eun-Taex Oh
- Department of Biomedical Sciences, College of Medicine, Inha University, Incheon 22212, Republic of Korea
| | - Ha Gyeong Kim
- Program in Biomedical Science & Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Chul Hoon Kim
- Department of Pharmacology, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Jeonghun Lee
- Department of Polymer Science & Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Chulhee Kim
- Department of Polymer Science & Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Jae-Seon Lee
- Program in Biomedical Science & Engineering, Inha University, Incheon 22212, Republic of Korea.,Department of Molecular Medicine, College of Medicine, Inha University, Incheon 22212, Republic of Korea.,Research Center for Controlling Intracellular Communication, College of Medicine, Inha University, Incheon 22212, Republic of Korea
| | - Yunmi Cho
- Program in Biomedical Science & Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Heon Joo Park
- Program in Biomedical Science & Engineering, Inha University, Incheon 22212, Republic of Korea.,Research Center for Controlling Intracellular Communication, College of Medicine, Inha University, Incheon 22212, Republic of Korea.,Department of Microbiology, College of Medicine, Inha University, Incheon 22212, Republic of Korea
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2
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Anwaier G, Lian G, Ma GZ, Shen WL, Lee CI, Lee PL, Chang ZY, Wang YX, Tian XY, Gao XL, Chiu JJ, Qi R. Punicalagin Attenuates Disturbed Flow-Induced Vascular Dysfunction by Inhibiting Force-Specific Activation of Smad1/5. Front Cell Dev Biol 2021; 9:697539. [PMID: 34262908 PMCID: PMC8273543 DOI: 10.3389/fcell.2021.697539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 06/07/2021] [Indexed: 11/17/2022] Open
Abstract
Background Pathophysiological vascular remodeling in response to disturbed flow with low and oscillatory shear stress (OSS) plays important roles in atherosclerosis progression. Pomegranate extraction (PE) was reported having anti-atherogenic effects. However, whether it can exert a beneficial effect against disturbed flow-induced pathophysiological vascular remodeling to inhibit atherosclerosis remains unclear. The present study aims at investigating the anti-atherogenic effects of pomegranate peel polyphenols (PPP) extraction and its purified compound punicalagin (PU), as well as their protective effects on disturbed flow-induced vascular dysfunction and their underlying molecular mechanisms. Methods The anti-atherogenic effects of PPP/PU were examined on low-density lipoprotein receptor knockout mice fed with a high fat diet. The vaso-protective effects of PPP/PU were examined in rat aortas using myograph assay. A combination of in vivo experiments on rats and in vitro flow system with human endothelial cells (ECs) was used to investigate the pharmacological actions of PPP/PU on EC dysfunction induced by disturbed flow. In addition, the effects of PPP/PU on vascular smooth muscle cell (VSMC) dysfunction were also examined. Results PU is the effective component in PPP against atherosclerosis. PPP/PU evoked endothelium-dependent relaxation in rat aortas. PPP/PU inhibited the activation of Smad1/5 in the EC layers at post-stenotic regions of rat aortas exposed to disturbed flow with OSS. PPP/PU suppressed OSS-induced expression of cell cycle regulatory and pro-inflammatory genes in ECs. Moreover, PPP/PU inhibited inflammation-induced VSMC dysfunction. Conclusion PPP/PU protect against OSS-induced vascular remodeling through inhibiting force-specific activation of Smad1/5 in ECs and this mechanism contributes to their anti-atherogenic effects.
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Affiliation(s)
- Gulinigaer Anwaier
- Department of Pharmacology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.,Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, China.,National Health Commission (NHC) Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Peking University, Beijing, China.,Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, Peking University, Beijing, China
| | - Guan Lian
- Department of Pharmacology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.,Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, China.,National Health Commission (NHC) Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Peking University, Beijing, China.,Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, Peking University, Beijing, China
| | - Gui-Zhi Ma
- College of Pharmacy, Xinjiang Medical University, Xinjiang, China.,Xinjiang Key Laboratory of Active Components and Drug Release Technology of Natural Drugs, Xinjiang, China
| | - Wan-Li Shen
- Department of Pharmacology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.,Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, China.,National Health Commission (NHC) Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Peking University, Beijing, China.,Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, Peking University, Beijing, China
| | - Chih-I Lee
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Pei-Ling Lee
- Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Zhan-Ying Chang
- College of Pharmacy, Xinjiang Medical University, Xinjiang, China.,Xinjiang Key Laboratory of Active Components and Drug Release Technology of Natural Drugs, Xinjiang, China
| | - Yun-Xia Wang
- Department of Pharmacology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.,Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, China.,National Health Commission (NHC) Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Peking University, Beijing, China.,Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, Peking University, Beijing, China
| | - Xiao-Yu Tian
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Xiao-Li Gao
- College of Pharmacy, Xinjiang Medical University, Xinjiang, China.,Xinjiang Key Laboratory of Active Components and Drug Release Technology of Natural Drugs, Xinjiang, China
| | - Jeng-Jiann Chiu
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.,Taipei Heart Institute, Taipei Medical University, Taipei, Taiwan.,Institute of Cellular and System Medicine, National Health Research Institutes, Miaoli, Taiwan.,Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu, Taiwan.,Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan
| | - Rong Qi
- Department of Pharmacology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.,Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China.,State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, China.,National Health Commission (NHC) Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Peking University, Beijing, China.,Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, Peking University, Beijing, China
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3
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Li S, Yu G, Huang W, Wang R, Pu P, Chen M. RING finger protein 10 is a potential drug target for diabetic vascular complications. Mol Med Rep 2019; 20:931-938. [PMID: 31173254 PMCID: PMC6625204 DOI: 10.3892/mmr.2019.10358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 02/28/2019] [Indexed: 12/23/2022] Open
Abstract
Vascular remodeling induced by long-term hyperglycaemia is the main pathological process in diabetic vascular complications. Thus, vascular remodeling may be a potential therapeutic target in diabetes mellitus (DM) with macrovascular disease. The present study aimed to investigate the effect of RING finger protein 10 (RNF10) on vascular remodeling under conditions of chronic hyperglycaemia stimulation. We found that overexpression of RNF10 clearly decreased intimal thickness and attenuated vascular remodeling in DM. TUNEL staining showed that apoptosis was clearly inhibited, an effect that may be mediated by decreases in Bcl-2 protein expression. Quantitative analysis demonstrated that overexpression of RNF10 could suppress inflammation by reducing the levels of TNF-α, and MCP-1 mRNA and NF-κB protein. Meanwhile, overexpression of RNF10 prevented vascular smooth muscle cell (VSMC) hyperproliferation through the downregulation of cyclin D1 and CDK4 proteins. Notably, short hairpin RNF10 (shRNF10) greatly aggravated the pathological responses of diabetic vascular remodeling. These outcomes revealed that the differential expression of RNF10 had a completely opposite effect on vascular damage under hyperglycaemia, further displaying the core function of RNF10 in regulating vascular remodeling induced by diabetes. Consequently, RNF10 could be a novel target for the treatment of diabetic vascular complications.
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Affiliation(s)
- Siyu Li
- Department of Cardiology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Guiquan Yu
- Department of Cardiology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Wei Huang
- Department of Cardiology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Ruiyu Wang
- Department of Cardiology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Peng Pu
- Department of Cardiology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Ming Chen
- Department of Cardiology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
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4
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Lee CT, Boeshore KL, Wu C, Becker KG, Errico SL, Mash DC, Freed WJ. Cocaine promotes primary human astrocyte proliferation via JNK-dependent up-regulation of cyclin A2. Restor Neurol Neurosci 2018; 34:965-976. [PMID: 27834787 DOI: 10.3233/rnn-160676] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE Astrocytes perform a plethora of important functions in the central nervous system (CNS) and are involved in cocaine-evoked synaptic plasticity. Previously, we showed that while cocaine decreased cyclin A2 expression in primary human neural progenitor cells, it increased cyclin A2 expression in human astrocytes. Since cyclin A2 is an essential regulator of the cell cycle, the aim of the present study is to clarify the effect of cocaine on proliferation of human astrocytes and elucidate the underlying molecular mechanisms. METHODS Primary human astrocytes were treated with either 1, 10, or 100 μM cocaine for 48 hr, and cell proliferation was measured using the CyQUANT cell proliferation assay. To elucidate the molecular mechanisms through which cocaine affects the proliferation of astrocytes, we analyzed gene expression profiles in cocaine-treated primary human astrocytes using a human focused cDNA array. Gene ontology/pathway enrichment analysis, STRING protein-protein interaction analysis, RT-qPCR, and western blotting were used to identify signal transduction pathways that are involved in cocaine-induced astrocyte dysfunction. RESULTS Cocaine at 10 and 100 μM significantly increased human astrocyte proliferation. Gene expression profiling revealed the JNK MAP kinase pathway as a driver of cell proliferation affected by cocaine in human astrocytes. Further experiments showed that cocaine-induced JNK activation induced up-regulation of cyclin A2, leading to enhanced proliferation of human astrocytes. CONCLUSION Cocaine-induced abnormal increases in the number of astrocytes may cause disruption in neuron-glia signaling and contribute to synaptic impairment in the CNS. Understanding the mechanisms of cocaine's effects on human astrocytes may help to reveal the involvement of glial cells in addictive behaviors.
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Affiliation(s)
- Chun-Ting Lee
- Section on Development and Plasticity, Cellular Neurobiology Research Branch, Intramural Research Program (IRP), National Institute on Drug Abuse, National Institutes of Health (NIH), Baltimore, MD, USA.,Department of Neurology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | | | - Chun Wu
- Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Kevin G Becker
- Gene Expression and Genomics Unit, Research Resources Branch, IRP, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Stacie L Errico
- Section on Development and Plasticity, Cellular Neurobiology Research Branch, Intramural Research Program (IRP), National Institute on Drug Abuse, National Institutes of Health (NIH), Baltimore, MD, USA
| | - Deborah C Mash
- Department of Neurology, Miller School of Medicine, University of Miami, Miami, FL, USA.,Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - William J Freed
- Section on Development and Plasticity, Cellular Neurobiology Research Branch, Intramural Research Program (IRP), National Institute on Drug Abuse, National Institutes of Health (NIH), Baltimore, MD, USA.,Department of Biology, Lebanon Valley College, Annville, PA, USA
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5
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Nowwarote N, Pavasant P, Osathanon T. Role of endogenous basic fibroblast growth factor in stem cells isolated from human exfoliated deciduous teeth. Arch Oral Biol 2014; 60:408-15. [PMID: 25526625 DOI: 10.1016/j.archoralbio.2014.11.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/05/2014] [Accepted: 11/25/2014] [Indexed: 12/01/2022]
Abstract
OBJECTIVE This study aimed to investigate the role of endogenous basic fibroblast growth factor (bFGF) in stem cells isolated from human exfoliated deciduous teeth. METHODS Cells were isolated from dental pulp tissues of human exfoliated deciduous teeth. The expression of stem cell markers was determined using conventional semi-quantitative polymerase chain reaction (PCR) and flow cytometry. The multipotential differentiation ability was also examined. The lentiviral shRNA or fibroblast growth factor receptor (FGFR) inhibitor was employed to inhibit bFGF mRNA expression and signal transduction, respectively. The colony formation ability was determined by low-density cell seeding protocol. The mRNA expression was evaluated using real-time quantitative PCR. The osteogenic differentiation was examined using alkaline phosphatase enzymatic activity assay and alizarin red staining. RESULTS The results demonstrated that the cells isolated from human exfoliated deciduous teeth (SHEDs) exhibited stem cell characteristics, regarding marker expression and multipotential differentiation ability (osteogenic, adipogenic, and neurogenic lineage). The sh-bFGF transduced SHEDs had lower colony forming unit and higher mineralization than those of the control. Similarly, the decrease of colony number and the increase of mineral deposition were noted upon exposing cells to FGFR chemical inhibitor. CONCLUSION These results imply that the endogenous bFGF may participate in the colony formation and osteogenic differentiation ability. In addition, the inhibition of bFGF signalling may be useful to enhance osteogenic differentiation of stem cells.
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Affiliation(s)
- Nunthawan Nowwarote
- Research Unit of Mineralized Tissue, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand.
| | - Prasit Pavasant
- Research Unit of Mineralized Tissue, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand; Department of Anatomy, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand.
| | - Thanaphum Osathanon
- Research Unit of Mineralized Tissue, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand; Department of Anatomy, Faculty of Dentistry, Chulalongkorn University, Bangkok 10330, Thailand.
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6
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Munteanu A, Ohler U, Gordân R. COUGER--co-factors associated with uniquely-bound genomic regions. Nucleic Acids Res 2014; 42:W461-7. [PMID: 24861628 PMCID: PMC4086139 DOI: 10.1093/nar/gku435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Most transcription factors (TFs) belong to protein families that share a common DNA binding domain and have very similar DNA binding preferences. However, many paralogous TFs (i.e. members of the same TF family) perform different regulatory functions and interact with different genomic regions in the cell. A potential mechanism for achieving this differential in vivo specificity is through interactions with protein co-factors. Computational tools for studying the genomic binding profiles of paralogous TFs and identifying their putative co-factors are currently lacking. Here, we present an interactive web implementation of COUGER, a classification-based framework for identifying protein co-factors that might provide specificity to paralogous TFs. COUGER takes as input two sets of genomic regions bound by paralogous TFs, and it identifies a small set of putative co-factors that best distinguish the two sets of sequences. To achieve this task, COUGER uses a classification approach, with features that reflect the DNA-binding specificities of the putative co-factors. The identified co-factors are presented in a user-friendly output page, together with information that allows the user to understand and to explore the contributions of individual co-factor features. COUGER can be run as a stand-alone tool or through a web interface: http://couger.oit.duke.edu.
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Affiliation(s)
- Alina Munteanu
- Faculty of Computer Science, Alexandru I. Cuza University, Iasi 700483, Romania Berlin Institute for Medical Systems Biology, Max Delbruck Center, 13125 Berlin, Germany
| | - Uwe Ohler
- Berlin Institute for Medical Systems Biology, Max Delbruck Center, 13125 Berlin, Germany Department of Biostatistics and Bioinformatics, Duke University, Durham, NC 27708, USA
| | - Raluca Gordân
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC 27708, USA
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7
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Silvestre-Roig C, Fernández P, Mansego ML, van Tiel CM, Viana R, Anselmi CV, Condorelli G, de Winter RJ, Martín-Fuentes P, Solanas-Barca M, Civeira F, Focaccio A, de Vries CJM, Chaves FJ, Andrés V. Genetic variants in CCNB1 associated with differential gene transcription and risk of coronary in-stent restenosis. ACTA ACUST UNITED AC 2014; 7:59-70. [PMID: 24395923 DOI: 10.1161/circgenetics.113.000305] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The development of diagnostic tools to assess restenosis risk after stent deployment may enable the intervention to be tailored to the individual patient, for example, by targeting the use of drug-eluting stent to high-risk patients, with the goal of improving safety and reducing costs. The CCNB1 gene (encoding cyclin B1) positively regulates cell proliferation, a key component of in-stent restenosis. Therefore, we hypothesized that single-nucleotide polymorphisms in CCNB1 may serve as useful tools in risk stratification for in-stent restenosis. METHODS AND RESULTS We identified 3 single-nucleotide polymorphisms in CCNB1 associated with increased restenosis risk in a cohort of 284 patients undergoing coronary angioplasty and stent placement (rs350099: TT versus CC+TC; odds ratio [OR], 1.82; 95% confidence interval [CI], 1.09-3.03; P=0.023; rs350104: CC versus CT+TT; OR, 1.82; 95% CI, 1.02-3.26; P=0.040; and rs164390: GG versus GT+TT; OR, 2.27; 95% CI, 1.33-3.85; P=0.002). These findings were replicated in another cohort study of 715 patients (rs350099: TT versus CC+TC; OR, 1.88; 95% CI, 0.92-3.81; P=0.080; rs350104: CC versus CT+TT; OR, 2.23; 95% CI, 1.18-4.25; P=0.016; and rs164390: GG versus GT+TT; OR, 1.87; 95% CI, 1.03-3.47; P=0.040). Moreover, the haplotype containing all 3 risk alleles is associated with higher CCNB1 mRNA expression in circulating lymphocytes and increased in-stent restenosis risk (OR, 1.43; 95% CI, 1.00-1.823; P=0.039). The risk variants of rs350099, rs350104, and rs164390 are associated with increased reporter gene expression through binding of transcription factors nuclear factor-Y, activator protein 1, and specificity protein 1, respectively. CONCLUSIONS Allele-dependent transcriptional regulation of CCNB1 associated with rs350099, rs350104, and rs164390 affects the risk of in-stent restenosis. These findings reveal these common genetic variations as attractive diagnostic tools in risk stratification for restenosis.
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8
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Bi D, Toyama K, Lemaître V, Takai J, Fan F, Jenkins DP, Wulff H, Gutterman DD, Park F, Miura H. The intermediate conductance calcium-activated potassium channel KCa3.1 regulates vascular smooth muscle cell proliferation via controlling calcium-dependent signaling. J Biol Chem 2013; 288:15843-53. [PMID: 23609438 PMCID: PMC3668741 DOI: 10.1074/jbc.m112.427187] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 04/12/2013] [Indexed: 01/14/2023] Open
Abstract
The intermediate conductance calcium-activated potassium channel KCa3.1 contributes to a variety of cell activation processes in pathologies such as inflammation, carcinogenesis, and vascular remodeling. We examined the electrophysiological and transcriptional mechanisms by which KCa3.1 regulates vascular smooth muscle cell (VSMC) proliferation. Platelet-derived growth factor-BB (PDGF)-induced proliferation of human coronary artery VSMCs was attenuated by lowering intracellular Ca(2+) concentration ([Ca(2+)]i) and was enhanced by elevating [Ca(2+)]i. KCa3.1 blockade or knockdown inhibited proliferation by suppressing the rise in [Ca(2+)]i and attenuating the expression of phosphorylated cAMP-response element-binding protein (CREB), c-Fos, and neuron-derived orphan receptor-1 (NOR-1). This antiproliferative effect was abolished by elevating [Ca(2+)]i. KCa3.1 overexpression induced VSMC proliferation, and potentiated PDGF-induced proliferation, by inducing CREB phosphorylation, c-Fos, and NOR-1. Pharmacological stimulation of KCa3.1 unexpectedly suppressed proliferation by abolishing the expression and activity of KCa3.1 and PDGF β-receptors and inhibiting the rise in [Ca(2+)]i. The stimulation also attenuated the levels of phosphorylated CREB, c-Fos, and cyclin expression. After KCa3.1 blockade, the characteristic round shape of VSMCs expressing high l-caldesmon and low calponin-1 (dedifferentiation state) was maintained, whereas KCa3.1 stimulation induced a spindle-shaped cellular appearance, with low l-caldesmon and high calponin-1. In conclusion, KCa3.1 plays an important role in VSMC proliferation via controlling Ca(2+)-dependent signaling pathways, and its modulation may therefore constitute a new therapeutic target for cell proliferative diseases such as atherosclerosis.
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Affiliation(s)
- Dan Bi
- From the Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada 89557
| | - Kazuyoshi Toyama
- the Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| | - Vincent Lemaître
- From the Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada 89557
| | - Jun Takai
- From the Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada 89557
| | - Fan Fan
- the Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| | - David P. Jenkins
- the Department of Pharmacology, University of California, Davis, California 95616
| | - Heike Wulff
- the Department of Pharmacology, University of California, Davis, California 95616
| | - David D. Gutterman
- the Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| | - Frank Park
- the Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| | - Hiroto Miura
- From the Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada 89557
- the Department of Medicine and Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
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9
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Hirai H, Satoh H, Kudoh A, Watanabe T. Interaction between resistin and adiponectin in the proliferation of rat vascular smooth muscle cells. Mol Cell Endocrinol 2013; 366:108-16. [PMID: 23267839 DOI: 10.1016/j.mce.2012.12.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 11/15/2012] [Accepted: 12/14/2012] [Indexed: 11/19/2022]
Abstract
We investigated the effect between resistin and adiponectin on the proliferation of vascular smooth muscle cells (VSMCs). We confirmed that resistin significantly increases the number of rat VSMCs as well as thymidine incorporation with them, whereas adiponectin diminishes resistin-induced cell proliferation. Resistin significantly increased p42/44 mitogen-activated protein kinase (MAPK) phosphorylation within rat VSMCs, whereas adiponectin inhibited resistin-induced MAPK phosphorylation. Moreover, resistin significantly increased c-fos expression, whereas adiponectin suppressed resistin-induced c-fos expression. Cell cycle progression is a tightly controlled event that is negatively regulated by cyclin-dependent kinases inhibitors (CDKIs) such as p53, p21, and p27. Resistin significantly decreased the expression of these CDKIs, whereas adiponectin restored the resistin-induced decrease in CDKIs expression. These effects were abolished in the MAPK inhibitors. In conclusion, resistin plays a role in the development of atherosclerosis, whereas adiponectin may be an important in its prevention in insulin-resistant patients.
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Affiliation(s)
- Hiroyuki Hirai
- Department of Nephrology, Fukushima Medical University, 1 Hikarigaoka, Fukushima-City, Fukushima 960-1295, Japan
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10
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Shukla V, Cuenin C, Dubey N, Herceg Z. Loss of histone acetyltransferase cofactor transformation/transcription domain-associated protein impairs liver regeneration after toxic injury. Hepatology 2011; 53:954-63. [PMID: 21319192 DOI: 10.1002/hep.24120] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 12/02/2010] [Indexed: 01/12/2023]
Abstract
Organ regeneration after toxin challenge or physical injury requires a prompt and balanced cell-proliferative response; a well-orchestrated cascade of gene expression is needed to regulate transcription factors and proteins involved in cell cycle progression and cell proliferation. After liver injury, cell cycle entry and progression of hepatocytes are believed to require concerted efforts of transcription factors and histone-modifying activities; however, the actual underlying mechanisms remain largely unknown. The purpose of our study was to investigate the role of the histone acetyltransferase (HAT) cofactor transformation/transcription domain-associated protein (TRRAP) and histone acetylation in the regulation of cell cycle and liver regeneration. To accomplish our purpose, we used a TRRAP conditional knockout mouse model combined with toxin-induced hepatic injury. After we treated the mice with a carbon tetrachloride toxin, conditional ablation of the TRRAP gene in those mice severely impaired liver regeneration and compromised cell cycle entry and progression of hepatocytes. Furthermore, loss of TRRAP impaired the induction of early and late cyclins in regenerating livers by compromising histone acetylation and transcription factor binding at the promoters of the cyclin genes. Our results demonstrate that TRRAP and TRRAP/HAT-mediated acetylation play an important role in liver regeneration after toxic injury and provide insight into the mechanism by which TRRAP/HATs orchestrate the expression of the cyclin genes during cell cycle entry and progression.
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Affiliation(s)
- Vivek Shukla
- International Agency for Research on Cancer (IARC), Lyon, France.
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11
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Sarsour EH, Kumar MG, Chaudhuri L, Kalen AL, Goswami PC. Redox control of the cell cycle in health and disease. Antioxid Redox Signal 2009; 11:2985-3011. [PMID: 19505186 PMCID: PMC2783918 DOI: 10.1089/ars.2009.2513] [Citation(s) in RCA: 284] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The cellular oxidation and reduction (redox) environment is influenced by the production and removal of reactive oxygen species (ROS). In recent years, several reports support the hypothesis that cellular ROS levels could function as ''second messengers'' regulating numerous cellular processes, including proliferation. Periodic oscillations in the cellular redox environment, a redox cycle, regulate cell-cycle progression from quiescence (G(0)) to proliferation (G(1), S, G(2), and M) and back to quiescence. A loss in the redox control of the cell cycle could lead to aberrant proliferation, a hallmark of various human pathologies. This review discusses the literature that supports the concept of a redox cycle controlling the mammalian cell cycle, with an emphasis on how this control relates to proliferative disorders including cancer, wound healing, fibrosis, cardiovascular diseases, diabetes, and neurodegenerative diseases. We hypothesize that reestablishing the redox control of the cell cycle by manipulating the cellular redox environment could improve many aspects of the proliferative disorders.
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Affiliation(s)
- Ehab H Sarsour
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa , Iowa City, Iowa, USA
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12
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Malabanan KP, Kanellakis P, Bobik A, Khachigian LM. Activation Transcription Factor-4 Induced by Fibroblast Growth Factor-2 Regulates Vascular Endothelial Growth Factor-A Transcription in Vascular Smooth Muscle Cells and Mediates Intimal Thickening in Rat Arteries Following Balloon Injury. Circ Res 2008; 103:378-87. [DOI: 10.1161/circresaha.107.168682] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Activation transcription factor (ATF)-4 is a member of the ATF/CREB family of basic leucine zipper transcription factors that regulates cellular responses to a variety of stresses. The role of ATF-4 in smooth muscle cells of the vessel wall is completely unknown. Here, we show that ATF-4 expression is induced in smooth muscle cells in response to injury, both in vitro using a model of mechanical injury and in the media of balloon-injured rat carotid arteries. We demonstrate that ATF-4 is activated by fibroblast growth factor (FGF)-2, an injury-induced mitogen, through the phosphatidylinositol 3-kinase pathway. Injury also activates vascular endothelial growth factor (VEGF)-A, whose expression is stimulated by ATF-4 overexpression and exposure to FGF-2. FGF-2 induces ATF-4 binding to a recognition element located in the VEGF-A gene at +1767 bp and luciferase reporter gene expression dependent on this site. Moreover, ATF-4 knockdown with small interfering RNA or ATF-4 deficiency ameliorates FGF-2–inducible VEGF-A expression. Intraluminal delivery of ATF-4 small interfering RNA in rat carotid arteries blocks balloon injury–inducible ATF-4 and VEGF-A expression after 4 hours and intimal thickening after 14 days. These findings reveal, for the first time, the induction of ATF-4 by both vascular injury and FGF-2. ATF-4 serves as a conduit for the inducible expression of 1 growth factor by another during the process of intimal thickening.
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Affiliation(s)
- Kristine P. Malabanan
- From the Centre for Vascular Research (K.P.M., L.M.K.), School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney; and Baker Heart Research Institute (P.K., A.B.), Melbourne, Australia
| | - Peter Kanellakis
- From the Centre for Vascular Research (K.P.M., L.M.K.), School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney; and Baker Heart Research Institute (P.K., A.B.), Melbourne, Australia
| | - Alexander Bobik
- From the Centre for Vascular Research (K.P.M., L.M.K.), School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney; and Baker Heart Research Institute (P.K., A.B.), Melbourne, Australia
| | - Levon M. Khachigian
- From the Centre for Vascular Research (K.P.M., L.M.K.), School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney; and Baker Heart Research Institute (P.K., A.B.), Melbourne, Australia
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13
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PGC-1alpha inhibits oleic acid induced proliferation and migration of rat vascular smooth muscle cells. PLoS One 2007; 2:e1137. [PMID: 17987121 PMCID: PMC2043491 DOI: 10.1371/journal.pone.0001137] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2007] [Accepted: 10/19/2007] [Indexed: 11/19/2022] Open
Abstract
Background Oleic acid (OA) stimulates vascular smooth muscle cell (VSMC) proliferation and migration. The precise mechanism is still unclear. We sought to investigate the effects of peroxisome proliferator-activated receptor gamma (PPARγ) coactivator-1 alpha (PGC-1α) on OA-induced VSMC proliferation and migration. Principal Findings Oleate and palmitate, the most abundant monounsaturated fatty acid and saturated fatty acid in plasma, respectively, differently affect the mRNA and protein levels of PGC-1α in VSMCs. OA treatment resulted in a reduction of PGC-1α expression, which may be responsible for the increase in VSMC proliferation and migration caused by this fatty acid. In fact, overexpression of PGC-1α prevented OA-induced VSMC proliferation and migration while suppression of PGC-1α by siRNA enhanced the effects of OA. In contrast, palmitic acid (PA) treatment led to opposite effects. This saturated fatty acid induced PGC-1α expression and prevented OA-induced VSMC proliferation and migration. Mechanistic study demonstrated that the effects of PGC-1α on VSMC proliferation and migration result from its capacity to prevent ERK phosphorylation. Conclusions OA and PA regulate PGC-1α expression in VSMCs differentially. OA stimulates VSMC proliferation and migration via suppression of PGC-1α expression while PA reverses the effects of OA by inducing PGC-1α expression. Upregulation of PGC-1α in VSMCs provides a potential novel strategy in preventing atherosclerosis.
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14
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Casalino L, Bakiri L, Talotta F, Weitzman JB, Fusco A, Yaniv M, Verde P. Fra-1 promotes growth and survival in RAS-transformed thyroid cells by controlling cyclin A transcription. EMBO J 2007; 26:1878-90. [PMID: 17347653 PMCID: PMC1847654 DOI: 10.1038/sj.emboj.7601617] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Accepted: 01/25/2007] [Indexed: 11/09/2022] Open
Abstract
Fra-1 is frequently overexpressed in epithelial cancers and implicated in invasiveness. We previously showed that Fra-1 plays crucial roles in RAS transformation in rat thyroid cells and mouse fibroblasts. Here, we report a novel role for Fra-1 as a regulator of mitotic progression in RAS-transformed thyroid cells. Fra-1 expression and phosphorylation are regulated during the cell cycle, peaking at G2/M. Knockdown of Fra-1 caused a proliferative block and apoptosis. Although most Fra-1-knockdown cells accumulated in G2, a fraction of cells entering M-phase underwent abortive cell division and exhibited hallmarks of genomic instability (micronuclei, lagging chromosomes and anaphase bridges). Furthermore, we established a link between Fra-1 and the cell-cycle machinery by identifying cyclin A as a novel transcriptional target of Fra-1. During the cell cycle, Fra-1 was recruited to the cyclin A gene (ccna2) promoter, binding to previously unidentified AP-1 sites and the CRE. Fra-1 also induced the expression of JunB, which in turn interacts with the cyclin A promoter. Hence, Fra-1 induction is important in thyroid tumorigenesis, critically regulating cyclin expression and cell-cycle progression.
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Affiliation(s)
- Laura Casalino
- Institute of Genetics and Biophysics ‘A Buzzati Traverso', CNR, Naples, Italy
- Unit of Gene Expression and Disease, Department of Developmental Biology, Pasteur Institute, Paris, France
- Institute of Genetics and Biophysics ‘A Buzzati Traverso', CNR, Naples, Italy. Tel.: +39 0816132452; Fax: +39 0816132706; E-mail:
| | - Latifa Bakiri
- Research Institute of Molecular Pathology, Vienna, Austria
| | - Francesco Talotta
- Institute of Genetics and Biophysics ‘A Buzzati Traverso', CNR, Naples, Italy
| | - Jonathan B Weitzman
- Unit of Gene Expression and Disease, Department of Developmental Biology, Pasteur Institute, Paris, France
| | - Alfredo Fusco
- Department of Molecular and Cellular Pathology, University ‘Federico II', Naples, Italy
| | - Moshe Yaniv
- Unit of Gene Expression and Disease, Department of Developmental Biology, Pasteur Institute, Paris, France
| | - Pasquale Verde
- Institute of Genetics and Biophysics ‘A Buzzati Traverso', CNR, Naples, Italy
- Institute of Genetics and Biophysics ‘A Buzzati Traverso', CNR, Naples, Italy. E-mail:
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15
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Kamiya K, Sakakibara K, Ryer EJ, Hom RP, Leof EB, Kent KC, Liu B. Phosphorylation of the cyclic AMP response element binding protein mediates transforming growth factor beta-induced downregulation of cyclin A in vascular smooth muscle cells. Mol Cell Biol 2007; 27:3489-98. [PMID: 17325033 PMCID: PMC1899963 DOI: 10.1128/mcb.00665-06] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transforming growth factor beta (TGFbeta), a multifunctional cytokine associated with vascular injury, is a potent inhibitor of cell proliferation. The current results demonstrate that the TGFbeta-induced growth arrest of vascular smooth muscle cells (VSMCs) is associated with cyclin A downregulation. TGFbeta represses the cyclin A gene through a cyclic AMP (cAMP) response element, which complexes with the cAMP response element binding protein (CREB). The CREB-cyclin A promoter interaction is hindered by TGFbeta, preceded by a TGFbeta receptor-dependent CREB phosphorylation. Induction of CREB phosphorylation with forskolin or 6bnz-cAMP mimics TGFbeta's inhibitory effect on cyclin A expression. Conversely, inhibition of CREB phosphorylation with a CREB mutant in which the phosphorylation site at serine 133 was changed to alanine (CREB-S133A) upregulated cyclin A gene expression. Furthermore, the CREB-S133A mutant abolished TGFbeta-induced CREB phosphorylation, cyclin A downregulation, and growth inhibition. Since we have previously shown that the novel PKC isoform protein kinase C delta (PKCdelta) is activated by TGFbeta in VSMCs, we tested the role of this kinase in CREB phosphorylation and cyclin A downregulation. Inhibition of PKCdelta by a dominant-negative mutant or by targeted gene deletion blocked TGFbeta-induced CREB phosphorylation and cyclin A downregulation. Taken together, our data indicate that phosphorylation of CREB stimulated by TGFbeta is a critical step leading to the inhibition of cyclin A expression and, thus, VSMC proliferation.
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Affiliation(s)
- Kentaro Kamiya
- Department of Surgery, Weill Cornell Medical College of Cornell University, New York, NY 1002, USA
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16
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Peng J, Dong W, Chen L, Zou T, Qi Y, Liu Y. Brd2 is a TBP-associated protein and recruits TBP into E2F-1 transcriptional complex in response to serum stimulation. Mol Cell Biochem 2006; 294:45-54. [PMID: 17111193 DOI: 10.1007/s11010-006-9223-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Accepted: 05/01/2006] [Indexed: 10/23/2022]
Abstract
Brd2 is a novel protein kinase and plays a role in cell cycle-responsive transcription. Recent studies show that Brd2 contributes to E2F-1 regulated cell cycle progression. In this process, Brd2 exhibits scaffold or transcriptional adapter functions and mediates recruitment of both E2F-1 transcription factors and chromatin-remodelling activity to the E2F-1-resposive promoter. In the present study, we show that Brd2 is also a TBP-associated protein and a 26 amino acids peptide in the first bromodomain of Brd2 is essential for Brd2-TBP interaction. We found that serum stimulation of serum starved NIH/3T3 cells efficiently induces the formation of the Brd2-E2F-1-TBP complex in vivo. In this process, Brd2 plays a pivotal role in the recruitment of TBP into a E2F-1 transcriptional complex, as tested in overexpression assay and at the endogenous level. Furthermore, the 26 amino acid peptide that mediates Brd2-TBP interaction is proved to be critical for Brd2-dependent transactivation on E2F-1-responsive promoters, and moreover, Brd2 and E2F-1 may cooperatively participate in various serum-induced transactivation processes in Luciferase-reporter assays. Thus taken together, because Brd2 may recruit a HAT in its transactivational complex and E2F-1 has been found to stimulate transcription by recruiting acetyltransferase and cofactors GCN5, we predict that Brd2 and E2F-1 may act in a cooperative way to introduce an optimal environment for TBP binding to the TATA-element of gene promoters.
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Affiliation(s)
- Jinhong Peng
- National Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, Hubei, People's Republic of China
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17
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Sanz-González SM, Melero-Fernández de Mera R, Malek NP, Andrés V. Atheroma development in apolipoprotein E-null mice is not regulated by phosphorylation of p27(Kip1) on threonine 187. J Cell Biochem 2006; 97:735-43. [PMID: 16229012 DOI: 10.1002/jcb.20680] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Excessive cellular proliferation is thought to contribute to neointimal lesion development during atherosclerosis and restenosis after angioplasty. Inhibition of cyclin-dependent kinase (CDK) activity by p27 inhibits mammalian cell growth. Mounting evidence indicates that p27 negatively regulates neointimal thickening in animal models of restenosis and atherosclerosis, and its expression in human neointimal lesions is consistent with such a protective role. Cell cycle progression is facilitated by cyclinE/CDK2-dependent phosphorylation of p27 on threonine 187 (T187) during late G1. The purpose of this study was to assess whether this phosphorylation event plays a role during atherosclerosis. To this end, we generated apolipoprotein E-null mice with both p27 alleles replaced by a mutated form non-phosphorylatable at T187 (apoE-/-p27T187A mice) and investigated the kinetics of atheroma development in these animals compared to apoE-/- controls with an intact p27 gene. Fat feeding resulted in comparable level of hypercholesterolemia in both groups of mice. Surprisingly, aortic p27 expression was not increased in fat-fed apoE-/-p27T187A mice compared with apoE-/- controls. Moreover, atheroma size, lesion cellularity, proliferation, and apoptotic rates were undistinguishable in both groups of fat-fed mice. Thus, in contrast to previous studies that highlight the importance of p27 phosphorylation at T187 on the control of p27 expression and function in different tissues and pathophysiological scenarios, our findings demonstrate that this phosphorylation event is not implicated in the control of aortic p27 expression and atheroma progression in hypercholesterolemic mice.
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Affiliation(s)
- Silvia M Sanz-González
- Laboratory of Vascular Biology, Department of Molecular and Cellular Pathology and Therapy, Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Valencia, Spain
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18
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Cheong A, Bingham AJ, Li J, Kumar B, Sukumar P, Munsch C, Buckley NJ, Neylon CB, Porter KE, Beech DJ, Wood IC. Downregulated REST transcription factor is a switch enabling critical potassium channel expression and cell proliferation. Mol Cell 2005; 20:45-52. [PMID: 16209944 DOI: 10.1016/j.molcel.2005.08.030] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Revised: 07/08/2005] [Accepted: 08/25/2005] [Indexed: 10/25/2022]
Abstract
Induction of K(Ca)3.1 (IKCa) potassium channel plays an important role in vascular smooth muscle cell proliferation. Here, we report that the gene encoding K(Ca)3.1 (KCNN4) contains a functional repressor element 1-silencing transcription factor (REST or NRSF) binding site and is repressed by REST. Although not previously associated with vascular smooth muscle cells, REST is present and recruited to the KCNN4 gene in situ. Significantly, expression of REST declines when there is cellular proliferation, showing an inverse relationship with functional K(Ca)3.1. Downregulated REST and upregulated K(Ca)3.1 are also evident in smooth muscle cells of human neointimal hyperplasia grown in organ culture. Furthermore, inhibition of K(Ca)3.1 suppresses neointimal formation, and exogenous REST reduces the functional impact of K(Ca)3.1. Here, we show REST plays a previously unrecognized role as a switch regulating potassium channel expression and consequently the phenotype of vascular smooth muscle cells and human vascular disease.
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Affiliation(s)
- Alex Cheong
- Institute of Membrane and Systems Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
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19
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Sinha A, Faller D, Denis G. Bromodomain analysis of Brd2-dependent transcriptional activation of cyclin A. Biochem J 2005; 387:257-69. [PMID: 15548137 PMCID: PMC1134954 DOI: 10.1042/bj20041793] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cyclin A is regulated primarily through transcription control during the mammalian cell cycle. A dual mechanism of cyclin A transcriptional repression involves, on the one hand, promoter-bound inhibitory complexes of E2F transcription factors and RB (retinoblastoma) family proteins, and on the other, chromatin-directed histone deacetylase activity that is recruited to the cyclin A promoter early in the cell cycle in association with these RB proteins. This dual regulation maintains transcriptional silence of the cyclin A locus until its transcription is required in S-phase. At that time, RB family members dissociate from E2F proteins and nucleosomal restructuring of the locus takes place, to permit transcriptional activation and resultant S-phase progression to proceed. We have identified a double bromo-domain-containing protein Brd2, which exhibits apparent 'scaffold' or transcriptional adapter functions and mediates recruitment of both E2F transcription factors and chromatin-remodelling activity to the cyclin A promoter. We have shown previously that Brd2-containing nuclear, multiprotein complexes contain E2F-1 and -2. In the present study, we show that, in S-phase, they also contain histone H4-directed acetylase activity. Overexpression of Brd2 in fibroblasts accelerates the cell cycle through increased expression of cyclin A and its associated cyclin-dependent kinase activity. Chromatin immunoprecipitation studies show that Brd2 is physically present at the cyclin A promoter and its overexpression promotes increased histone H4 acetylation at the promoter as it becomes transcriptionally active, suggesting a new model for the dual regulation of cyclin A.
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Affiliation(s)
- Anupama Sinha
- Cancer Research Center, Boston University School of Medicine, 80 East Concord Street, K521, Boston, MA 02118, U.S.A
| | - Douglas V. Faller
- Cancer Research Center, Boston University School of Medicine, 80 East Concord Street, K521, Boston, MA 02118, U.S.A
| | - Gerald V. Denis
- Cancer Research Center, Boston University School of Medicine, 80 East Concord Street, K521, Boston, MA 02118, U.S.A
- To whom correspondence should be addressed (email )
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20
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Fasciano S, Patel RC, Handy I, Patel CV. Regulation of vascular smooth muscle proliferation by heparin: inhibition of cyclin-dependent kinase 2 activity by p27(kip1). J Biol Chem 2005; 280:15682-9. [PMID: 15731113 PMCID: PMC3972062 DOI: 10.1074/jbc.m411458200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Uncontrolled proliferation of vascular smooth muscle cells (VSMCs) contribute to intimal hyperplasia during atherosclerosis and restenosis. Heparin is an antiproliferative agent for VSMCs and has been shown to block VSMC proliferation both in tissue culture systems and in animals. Despite the well documented antiproliferative actions of heparin, its cellular targets largely remain unknown. In an effort to characterize the mechanism of the antiproliferative property of heparin, we have analyzed the effect of heparin on cell cycle in VSMC. Our results indicate that the heparin-induced block in G(1) to S phase transition is imposed by p27(kip1)-mediated inhibition of cyclin-dependent kinase 2 activity. Further analysis of p27(kip1) mRNA levels showed that the increase in p27(kip1) protein levels in heparin-treated VSMC occurs at posttranscriptional levels. We present evidence that heparin causes stabilization of p27(kip1) protein during G(1) phase and thereby prevents activation of cyclin-dependent kinase 2.
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Affiliation(s)
- Stephen Fasciano
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Rekha C. Patel
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Indhira Handy
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Chandrashekhar V. Patel
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
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21
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Katabami M, Donninger H, Hommura F, Leaner VD, Kinoshita I, Chick JFB, Birrer MJ. Cyclin A is a c-Jun target gene and is necessary for c-Jun-induced anchorage-independent growth in RAT1a cells. J Biol Chem 2005; 280:16728-38. [PMID: 15737994 DOI: 10.1074/jbc.m413892200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Overexpression of c-Jun enables Rat1a cells to grow in an anchorage-independent manner. We used an inducible c-Jun system under the regulation of doxycycline in Rat1a cells to identify potential c-Jun target genes necessary for c-Jun-induced anchorage-independent growth. Induction of c-Jun results in sustained expression of cyclin A in the nonadherent state with only minimal expression in the absence of c-Jun. The promoter activity of cyclin A2 was 4-fold higher in Rat1a cells in which c-Jun expression was induced compared with the control cells. Chromatin immunoprecipitation demonstrated that c-Jun bound directly to the cyclin A2 promoter. Mutation analysis of the cyclin A2 promoter mapped the c-Jun regulatory site to an ATF site at position -80. c-Jun was able to bind to this site both in vitro and in vivo, and mutation of this site completely abolished promoter activity. Cyclin A1 was also elevated in c-Jun-overexpressing Rat1a cells; however, c-Jun did not regulate this gene directly, since it did not bind directly to the cyclin A1 promoter. Suppression of cyclin A expression via the introduction of a cyclin A antisense sequences significantly reduced the ability of c-Jun-overexpressing Rat1a cells to grow in an anchorage-independent fashion. Taken together, these results suggest that cyclin A is a target of c-Jun and is necessary but not sufficient for c-Jun-induced anchorage-independent growth. In addition, we demonstrated that the cytoplasmic oncogenes Ras and Src transcriptionally activated the cyclin A2 promoter via the ATF site at position -80. Using a dominant negative c-Jun mutant, TAM67, we showed that this transcriptional activation of cyclin A2 requires c-Jun. Thus, our results suggest that c-Jun is a mediator of the aberrant cyclin A2 expression associated with Ras/Src-induced transformation.
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Affiliation(s)
- Motoo Katabami
- Department of Cell and Cancer Biology, NCI, National Institutes of Health, Rockville, Maryland 20850, USA
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22
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Halawani D, Mondeh R, Stanton LA, Beier F. p38 MAP kinase signaling is necessary for rat chondrosarcoma cell proliferation. Oncogene 2004; 23:3726-31. [PMID: 15116104 DOI: 10.1038/sj.onc.1207422] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Chondrosarcomas represent the second most frequent class of primary skeletal malignancies. This tumor type is highly resistant to radiation therapy and currently available chemotherapies, thereby limiting treatment choice to surgical resection. Identifying the mechanisms responsible for chondrosarcoma cell proliferation is therefore crucial for the development of new treatment strategies. Here, we demonstrate a significant reduction in rat chondrosarcoma cell proliferation following treatment with pharmacological inhibitors (SB202190 and PD169316) of p38 mitogen-activated protein (MAP) kinases. In an attempt to dissect possible mechanisms, we investigated the effect of p38 inhibition on promoter activity of cell-cycle genes. Surprisingly, p38 inhibition resulted in upregulation of the activities of all three D-type cyclin promoters. In addition, p38 inhibitors induced increased transcription of the cell-cycle inhibitor p21(waf1/cip1). As expected, promoter activity of the cyclin A gene, which lies downstream of D-type cyclins and p21 in cell-cycle progression, was strongly reduced by p38 inhibitors. These effects were independent of a cyclic AMP response element and conferred by the proximal 150 nucleotides of the cyclin A promoter. Decreased transcription was accompanied by greatly reduced cyclin A protein levels upon p38 inhibition. These observations indicate complex regulation of chondrosarcoma cell-cycle progression by p38 signaling, and suggest that components of p38 MAP kinase pathways may be effective targets in the treatment of these tumors.
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Affiliation(s)
- Dalia Halawani
- Department of Physiology and Pharmacology, Canadian Institute of Health Research Group in Skeletal Development and Remodeling, University of Western Ontario, London, Ontario, Canada N6A 5C1
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23
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Landsberg JW, Yuan JXJ. Calcium and TRP channels in pulmonary vascular smooth muscle cell proliferation. Physiology (Bethesda) 2004; 19:44-50. [PMID: 15016901 DOI: 10.1152/nips.01457.2003] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ca(2+) is a major trigger for pulmonary vasoconstriction and a stimulus for pulmonary vascular smooth muscle cell proliferation. The transient receptor potential cation channels participate in regulating intracellular Ca(2+) and thus vascular contractility and cell proliferation. Upregulation of genes encoding these channels is involved in the development of pulmonary hypertension.
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Affiliation(s)
- Judd W Landsberg
- Department of Medicine, School of Medicine, University of California, San Diego, California 92103, USA
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24
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Sanz-González SM, Castro C, Pérez P, Andrés V. Role of E2F and ERK1/2 in STI571-mediated smooth muscle cell growth arrest and cyclin A transcriptional repression. Biochem Biophys Res Commun 2004; 317:972-9. [PMID: 15094364 DOI: 10.1016/j.bbrc.2004.03.143] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2004] [Indexed: 12/17/2022]
Abstract
Platelet-derived growth factor (PDGF) ligand and receptors (PDGF-R) activate smooth muscle cell (SMC) proliferation, a key event during vascular obstructive disease. The PDGF-R tyrosine kinase inhibitor STI571 attenuates SMC proliferation and experimental neointimal thickening. Here, we investigated the molecular mechanisms underlying STI571-dependent SMC growth arrest. STI571 abrogates PDGF-BB-dependent cyclin D1 and cyclin A protein expression and inhibits transcriptional activation of reporter genes driven by the human cyclin A gene promoter. Repression of cyclin A promoter activity by STI571 requires a functional E2F-binding site, and forced expression of E2F overrides this inhibitory effect. Moreover, STI571 inhibits E2F DNA-binding activity in SMCs. We also found that STI571 abrogates PDGF-BB-dependent activation of extracellular-regulated kinase 1 and 2 (ERK1/2), and forced activation of these factors impaired STI571-dependent inhibition of both cyclin A promoter activity and SMC proliferation. Thus, E2F and ERK1/2 play an important role in STI571-mediated SMC growth arrest and cyclin A transcriptional repression. These findings may have importance in the development of novel therapeutic strategies for the treatment of neointimal hyperplasia.
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MESH Headings
- Animals
- Becaplermin
- Benzamides
- Cell Cycle Proteins
- Cell Division/drug effects
- Cell Line
- Cyclin A/genetics
- Cyclin A/metabolism
- Cyclin D1/biosynthesis
- DNA-Binding Proteins
- E2F Transcription Factors
- Enzyme Inhibitors/pharmacology
- Humans
- Imatinib Mesylate
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Piperazines/antagonists & inhibitors
- Piperazines/pharmacology
- Platelet-Derived Growth Factor/antagonists & inhibitors
- Platelet-Derived Growth Factor/pharmacology
- Promoter Regions, Genetic
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Proto-Oncogene Proteins c-sis
- Pyrimidines/antagonists & inhibitors
- Pyrimidines/pharmacology
- Rats
- Rats, Wistar
- Receptors, Platelet-Derived Growth Factor/metabolism
- Repressor Proteins/metabolism
- Transcription Factors/metabolism
- Transcription, Genetic
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Affiliation(s)
- Silvia M Sanz-González
- Loboratory of Vascular Biology, Department of Molecular and Cellular Pathology and Therapy, Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Cientificas, Valencia, Spain
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25
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Tessari MA, Gostissa M, Altamura S, Sgarra R, Rustighi A, Salvagno C, Caretti G, Imbriano C, Mantovani R, Del Sal G, Giancotti V, Manfioletti G. Transcriptional activation of the cyclin A gene by the architectural transcription factor HMGA2. Mol Cell Biol 2004; 23:9104-16. [PMID: 14645522 PMCID: PMC309667 DOI: 10.1128/mcb.23.24.9104-9116.2003] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The HMGA2 protein belongs to the HMGA family of architectural transcription factors, which play an important role in chromatin organization. HMGA proteins are overexpressed in several experimental and human tumors and have been implicated in the process of neoplastic transformation. Hmga2 knockout results in the pygmy phenotype in mice and in a decreased growth rate of embryonic fibroblasts, thus indicating a role for HMGA2 in cell proliferation. Here we show that HMGA2 associates with the E1A-regulated transcriptional repressor p120(E4F), interfering with p120(E4F) binding to the cyclin A promoter. Ectopic expression of HMGA2 results in the activation of the cyclin A promoter and induction of the endogenous cyclin A gene. In addition, chromatin immunoprecipitation experiments show that HMGA2 associates with the cyclin A promoter only when the gene is transcriptionally activated. These data identify the cyclin A gene as a cellular target for HMGA2 and, for the first time, suggest a mechanism for HMGA2-dependent cell cycle regulation.
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Affiliation(s)
- Michela A Tessari
- Dipartimento di Biochimica, Biofisica e Chimica delle Macromolecole. Centre of Excellence in Biocristallography, University of Trieste, via L. Giorgieri 1, 34127 Trieste, Italy
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26
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Li Z, Ding M, Thiele CJ, Luo J. Ethanol inhibits brain-derived neurotrophic factor-mediated intracellular signaling and activator protein-1 activation in cerebellar granule neurons. Neuroscience 2004; 126:149-62. [PMID: 15145081 DOI: 10.1016/j.neuroscience.2004.03.028] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2004] [Indexed: 11/15/2022]
Abstract
Developmental exposure to ethanol causes profound damage to the cerebellum, ranging from aberration in neuronal differentiation to cell loss. As a major neurotrophic factor, brain-derived neurotrophic factor (BDNF) and its receptor TrkB are expressed in the developing, as well as adult, cerebellum. Many neurotrophic effects of BDNF are mediated by gene transcription. We hypothesized that ethanol interfered with BDNF signaling and disrupted BDNF-regulated transcriptional activity. Using a transgenic mouse model expressing an activator protein-1 (AP-1) luciferase reporter construct, we demonstrated that BDNF stimulated AP-1 transactivation in cultured cerebellar granule neurons. This observation was validated by the study using a human neuronal cell line expressing inducible TrkB (TB8 neuroblastoma cells). BDNF induced AP-1 transactivation, as well as increased the binding activity of AP-1 protein complex to a DNA sequence containing AP-1 sites in TB8 cells. BDNF-mediated AP-1 activation was mediated by PI3K/Akt and JNK pathways; BDNF activated Akt and JNKs, and blocking these pathways significantly inhibited BDNF-stimulated AP-1 transactivation. More importantly, ethanol inhibited BDNF-mediated activation of PI3K/Akt and JNKs, and blocked BDNF-stimulated AP-1 activation. Since ethanol did not affect either the expression or autophosphorylation of TrkB, it could be concluded that the site of ethanol action was downstream of TrkB. The present study establishes that this AP-1 reporter transgenic mouse model is valuable for assessing AP-1 activity in the CNS neurons. Our results provide an insight into molecular mechanism(s) of ethanol action.
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Affiliation(s)
- Z Li
- Department of Microbiology, West Virginia University School of Medicine, Robert C. Byrd Health Sciences Center, Morgantown, WV 26506, USA
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27
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Sunters A, Thomas DP, Yeudall WA, Grigoriadis AE. Accelerated cell cycle progression in osteoblasts overexpressing the c-fos proto-oncogene: induction of cyclin A and enhanced CDK2 activity. J Biol Chem 2003; 279:9882-91. [PMID: 14699150 DOI: 10.1074/jbc.m310184200] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Transgenic mice overexpressing the c-Fos oncoprotein develop osteosarcomas that are associated with deregulated expression of cell cycle genes. Here we have generated osteoblast cell lines expressing c-fos under the control of a tetracycline-regulatable promoter to investigate the role of c-Fos in osteoblast cell cycle control in vitro. Three stable subclones, AT9.2, AT9.3, and AT9.7, derived from MC3T3-E1 mouse osteoblasts, expressed high levels of exogenous c-fos mRNA and protein in the absence of tetracycline. Functional contribution of ectopic c-Fos to AP-1 complexes was confirmed by electromobility shift assays and transactivation of AP-1 reporter constructs. Induction of exogenous c-Fos in quiescent AT9.2 cells caused accelerated S-phase entry following serum stimulation, resulting in enhanced growth rate. Ectopic c-Fos resulted in increased expression of cyclins A and E protein levels, and premature activation of cyclin A-, cyclin E-, and cyclin-dependent kinase (CDK) 2-associated kinase activities, although cyclin D levels and CDK4 activity were not affected significantly in these cell lines. The enhanced CDK2 kinase activity was associated with a rapid, concomitant dissociation of p27 from CDK2-containing complexes. Deregulated cyclin A expression and CDK2 activity was also observed in primary mouse osteoblasts overexpressing c-Fos, but not in fibroblasts, and c-Fos transgenic tumor-derived osteosarcoma cells constitutively expressed high levels of cyclin A protein. These data suggest that overexpression of c-Fos in osteoblasts results in accelerated S phase entry as a result of deregulated cyclin A/E-CDK2 activity. This represents a novel role for c-Fos in osteoblast growth control and may provide c-Fos-overexpressing osteoblasts with a growth advantage during tumorigenesis.
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Affiliation(s)
- Andrew Sunters
- Department of Craniofacial Development, King's College London, Guy's Hospital, Guy's Tower, United Kingdom
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28
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Kim N, Chung J, Kim E, Han J. Changes in the Ca2+-activated K+ channels of the coronary artery during left ventricular hypertrophy. Circ Res 2003; 93:541-7. [PMID: 12907665 DOI: 10.1161/01.res.0000090087.66390.f2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
It has been suggested that impairment of smooth muscle cell (SMC) function by alterations in the Ca2+-activated K+ (KCa) channels accounts for the reduction in coronary reserve during left ventricular hypertrophy (LVH). However, this hypothesis has not been fully investigated. The main goal of this study was to assess whether the properties of KCa channels in coronary SMCs were altered during LVH. In patch-clamp experiments, the whole-cell currents of the KCa channels were reduced during LVH. The unitary current amplitude and open probability for the KCa channels were significantly reduced in LVH patches compared with control patches. The concentration-response curve of the KCa channel to [Ca2+]i was shifted to the right. Inhibition of the KCa channels by tetraethylammonium (TEA) was more pronounced in LVH cells than in control cells. Western blot analysis indicated no differences in KCa channel expression between the control and LVH coronary SM membranes. In contraction experiments, the effect of high K+ concentration on the resting tension of the LVH coronary artery was greater than on that of the control. The effect of TEA on the resting tension of the LVH coronary artery was reduced compared with the effect on the control. Our findings imply a novel mechanism for reduced coronary reserve during LVH.
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MESH Headings
- Animals
- Cells, Cultured
- Coronary Vessels/physiopathology
- Electric Conductivity
- Hypertrophy, Left Ventricular/chemically induced
- Hypertrophy, Left Ventricular/metabolism
- Hypertrophy, Left Ventricular/physiopathology
- Isoproterenol
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiopathology
- Myocardial Contraction
- Myocardium/cytology
- Patch-Clamp Techniques
- Potassium Channels, Calcium-Activated/metabolism
- Protein Subunits
- Rabbits
- Rats
- Rats, Sprague-Dawley
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Affiliation(s)
- Nari Kim
- Department of Physiology & Biophysics, College of Medicine, Inje University, Busanjin-Gu, Busan, Korea
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29
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Tokunou T, Shibata R, Kai H, Ichiki T, Morisaki T, Fukuyama K, Ono H, Iino N, Masuda S, Shimokawa H, Egashira K, Imaizumi T, Takeshita A. Apoptosis induced by inhibition of cyclic AMP response element-binding protein in vascular smooth muscle cells. Circulation 2003; 108:1246-52. [PMID: 12939230 DOI: 10.1161/01.cir.0000085164.13439.89] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The balance between apoptosis and proliferation of vascular smooth muscle cells (VSMCs) is believed to contribute to the vascular remodeling process. Cyclic AMP response element-binding protein (CREB) is a critical transcription factor for the survival of neuronal cells and T lymphocytes. However, the role of CREB in blood vessels is incompletely characterized. METHODS AND RESULTS Nuclear staining with Hoechst 33258 or propidium iodine showed an increase in apoptotic cells with activation of caspase-3 in VSMCs infected with adenovirus expressing the dominant-negative form of CREB (AdCREBM1). Basal expression of Bcl-2 and Bcl-2 promoter activity were decreased by infection with AdCREBM1. Immunohistochemistry revealed that CREB was mainly induced and activated in the neointimal alpha-smooth muscle actin-positive cells of rat carotid artery after balloon injury. Infection with AdCREBM1 suppressed neointimal formation (intima-media ratio) by 33.8% after 14 days of injury, which was accompanied by an increase in apoptosis as indicated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling-positive cells and a decrease in bromodeoxyuridine incorporation. CONCLUSIONS These results suggest that CRE-dependent gene transcription might play an important role in the survival and proliferation of VSMCs. CREB might be a novel transcription factor mediating the vascular remodeling process and a potential therapeutic target for atherosclerotic disease.
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MESH Headings
- Angioplasty, Balloon
- Animals
- Apoptosis/drug effects
- Apoptosis/physiology
- Bromodeoxyuridine/pharmacokinetics
- Carotid Artery, Common/drug effects
- Carotid Artery, Common/metabolism
- Cell Division
- Cells, Cultured
- Cyclic AMP Response Element-Binding Protein/antagonists & inhibitors
- Cyclic AMP Response Element-Binding Protein/genetics
- Cyclic AMP Response Element-Binding Protein/metabolism
- Disease Models, Animal
- Gene Expression/drug effects
- Genes, Dominant
- Genetic Vectors/administration & dosage
- Genetic Vectors/genetics
- In Situ Nick-End Labeling
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Rats
- Transfection
- Tunica Intima/drug effects
- Tunica Intima/metabolism
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Affiliation(s)
- Tomotake Tokunou
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, 812-8582 Fukuoka, Japan
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30
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Grösch S, Tegeder I, Schilling K, Maier TJ, Niederberger E, Geisslinger G. Activation of c-Jun-N-terminal-kinase is crucial for the induction of a cell cycle arrest in human colon carcinoma cells caused by flurbiprofen enantiomers. FASEB J 2003; 17:1316-8. [PMID: 12759338 DOI: 10.1096/fj.02-0919fje] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The unselective cyclooxygenase (COX) inhibitor S-flurbiprofen and its-in terms of COX-inhibition-"inactive" enantiomer R-flurbiprofen have been previously found to inhibit tumor development and growth in various animal models. The underlying mechanisms are unknown. Here, we show that both R- and S-flurbiprofen reduce survival of three colon cancer cell lines, which differ in the expression of COX-2 (HCT-15, no COX-2; Caco-2, inducible COX-2; and HT-29, constitutive COX-2). The IC50 for S- and R-flurbiprofen ranged from 250 to 450 microM. Both flurbiprofen enantiomers induced apoptosis in all three cell lines as indicated by DNA- and PARP-cleavage. In addition, R- and S-flurbiprofen caused a G1-cell cycle block. The latter was associated with an activation of c-Jun N-terminal kinase (JNK), an increase of the DNA binding activity of the transcription factor AP-1 and down-regulation of cyclin D1 expression. Western blot analysis, as well as supershift experiments, revealed that the AP-1 activation was associated with a change of AP-1 composition toward an increase of JunB. The JNK inhibitor SP600125 antagonized R- and S-flurbiprofen-induced AP-1 DNA binding, suppression of cyclin D1 expression, and the G1-cell cycle block. However, JNK inhibition had no effect on flurbiprofen-induced apoptosis. Hence, the cell cycle arrest is obviously mediated, at least in part, through JNK-activation, whereas R- and S-flurbiprofen-induced apoptosis is largely independent of JNK. Although in vitro effects of R- and S-flurbiprofen were indistinguishable, only R-flurbiprofen inhibited HCT-15 tumor growth in nude mice, suggesting the involvement of additional in vivo targets, which are differently affected by R- and S-flurbiprofen.
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Affiliation(s)
- Sabine Grösch
- pharmazentrum frankfurt, Institut für Klinische Pharmakologie, Klinikum der Johann Wolfgang Goethe Universität, Theodor Stern Kai 7, 60590 Frankfurt/Main, Germany.
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31
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Lin Z, Fillmore GC, Um TH, Elenitoba-Johnson KSJ, Lim MS. Comparative microarray analysis of gene expression during activation of human peripheral blood T cells and leukemic Jurkat T cells. J Transl Med 2003; 83:765-76. [PMID: 12808112 DOI: 10.1097/01.lab.0000073130.58435.e5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Activation of T cells involves a complex cascade of signal transduction pathways linking T-cell receptor engagement at the cell membrane to the transcription of multiple genes within the nucleus. The T-cell leukemia-derived cell line Jurkat has generally been used as a model system for the activation of T cells. However, genome-wide comprehensive studies investigating the activation status, and thus the appropriateness, of this cell line for this purpose have not been performed. We sought to compare the transcriptional profiles of phenotypically purified human CD2(+) T cells with those of Jurkat T cells during T-cell activation, using cDNA microarrays containing 6912 genes. About 300 genes were up-regulated by more than 2-fold during activation of both peripheral blood (PB) T cells and Jurkat T cells. The number of down-regulated genes was significantly lower than that of up-regulated genes. Only 79 genes in PB T cells and 37 genes in Jurkat T cells were down-regulated by more than 2-fold during activation. Comparison of gene expression during activation of Jurkat and PB T cells revealed a common set of genes that were up-regulated, such as Rho GTPase-activating protein 1, SKP2, CDC25A, T-cell specific transcription factor 7, cytoskeletal proteins, and signaling molecules. Genes that were commonly down-regulated in both PB T cells and Jurkat T cells included CDK inhibitors (p16, p19, p27), proapoptotic caspases, and the transcription factors c-fos and jun-B. After activation, 71 genes in PB T cells and only 3 genes in Jurkat T cells were up-regulated 4-fold or more. Of these up-regulated genes and expressed sequence tags, 44 were constitutively expressed at high levels in nonactivated Jurkat cells. Quantitative real-time RT-PCR analysis confirmed our microarray data. Our findings indicate that although there is significant overlap in the activation-associated transcriptional profiles in PB T cells compared with Jurkat T cells, there is a subset of genes showing differential expression patterns during the activation of the two cell types.
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Affiliation(s)
- Zhaosheng Lin
- Department of Pathology, ARUP Institute for Clinical and Experimental Pathology, University of Utah, Salt Lake City, Utah 84132, USA
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32
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Luvalle P, Ma Q, Beier F. The role of activating transcription factor-2 in skeletal growth control. J Bone Joint Surg Am 2003; 85-A Suppl 2:133-6. [PMID: 12721356 DOI: 10.2106/00004623-200300002-00018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Phyllis Luvalle
- Department of Anatomy and Cell Biology, University of Florida, Gainesville 32610, USA.
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33
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Huang H, Petkova SB, Cohen AW, Bouzahzah B, Chan J, Zhou JN, Factor SM, Weiss LM, Krishnamachary M, Mukherjee S, Wittner M, Kitsis RN, Pestell RG, Lisanti MP, Albanese C, Tanowitz HB. Activation of transcription factors AP-1 and NF-kappa B in murine Chagasic myocarditis. Infect Immun 2003; 71:2859-67. [PMID: 12704159 PMCID: PMC153290 DOI: 10.1128/iai.71.5.2859-2867.2003] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The myocardium of CD1 mice was examined for the activation of signal transduction pathways leading to cardiac inflammation and subsequent remodeling during Trypanosoma cruzi infection (Brazil strain). The activity of three pathways of the mitogen-activated protein kinases (MAPKs) was determined. Immunoblotting revealed a persistent elevation of phosphorylated (activated) extracellular-signal-regulated kinase (ERK), which regulates cell proliferation. During infection there was a transient activation of p38 MAPK but no activation of Jun N-terminal kinase. Early targets of activated ERK, c-Jun and c-Fos, were elevated during infection, as demonstrated by semiquantitative reverse transcription-PCR. Immunostaining revealed that the endothelium and the interstitial cells were most intensely stained with antibodies to c-Jun and c-Fos. Soon after infection, AP-1 and NF-kappa B DNA binding activity was increased. Protein levels of cyclin D1, the downstream target of ERK and NF-kappa B, were induced during acute infection. Immunostaining demonstrated increased expression of cyclin D1 in the vascular and endocardial endothelium, inflammatory cells, and the interstitial areas. Increased expression of the cyclin D1-specific phosphorylated retinoblastoma protein (Ser780) was also evident. Immunoblotting and immunostaining also demonstrated increased expression of proliferating cellular nuclear antigen that was predominantly present in the inflammatory cells, interstitial areas (i.e., fibroblasts), and endothelium. These data demonstrate that T. cruzi infection results in activation of the ERK-AP-1 pathway and NF-kappa B. Cyclin D1 expression was also increased. These observations provide a molecular basis for the activation of pathways involved in cardiac remodeling in chagasic cardiomyopathy.
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Affiliation(s)
- Huan Huang
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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34
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Li Z, Miller MW, Luo J. Effects of prenatal exposure to ethanol on the cyclin-dependent kinase system in the developing rat cerebellum. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2002; 139:237-45. [PMID: 12480138 DOI: 10.1016/s0165-3806(02)00573-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Prenatal exposure to ethanol inhibits neurogenesis in the developing cerebellum. Cyclin-dependent kinases (CDKs) are a family of protein kinases that play multiple roles in the regulation of cell proliferation, differentiation and survival. The activity of CDKs is positively regulated by CDK activators, cyclins, and negatively regulated by CDK inhibitors (CDKIs). We hypothesize that impaired cerebellar development induced by gestational ethanol exposure is mediated by disruption of the CDK system. Pregnant rats were fed ad libitum with an ethanol-containing liquid diet (Et) or pair-fed an isocaloric control diet (Ct). Cerebella were collected from pups (postnatal day (P) 0 through P21) and examined for CDK, cyclin, or CDKI expression using a quantitative immunoblotting procedure. In Ct-treated rats, the expression of CDK2 and its activator, cyclin A, paralleled the pattern of granule cell proliferation. Prenatal ethanol exposure produced a significant down-regulation of CDK2/cyclin A expression. Although the amounts of CDK4/CDK6 and their activator, cyclin D2, did not oscillate during postnatal development, their expression in Et-treated pups was significantly (P<0.05) higher than in controls. The expression of a CDK inhibitor, p27(Kip), was inversely correlated to proliferation of cerebellar granule progenitors. Prenatal ethanol exposure caused the down-regulation of p27(Kip) between P0 and P21. Thus, prenatal exposure to ethanol disturbed the expression of cell cycle machineries in the postnatal cerebellum. This may account for the teratogenic effects of ethanol on the developing cerebellum.
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Affiliation(s)
- Zheng Li
- Department of Microbiology, Immunology and Cell Biology, West Virginia University School of Medicine, Robert C. Byrd Health Science Center, P.O. Box 9177, Morgantown, WV 26506, USA
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35
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Andrecht S, Kolbus A, Hartenstein B, Angel P, Schorpp-Kistner M. Cell cycle promoting activity of JunB through cyclin A activation. J Biol Chem 2002; 277:35961-8. [PMID: 12121977 DOI: 10.1074/jbc.m202847200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
JunB, a major component of the AP-1 transcription factor, is known to act antagonistically to c-Jun in transcriptional regulation and is proposed to be a negative regulator of cell proliferation. Employing fibroblasts derived from E9.5 junB(-/-) mouse embryos we provide evidence for a novel cell cycle promoting role of JunB. Despite a normal proliferation rate, primary and immortalized junB(-/-) fibroblasts exhibited an altered cell cycle profile, which was characterized by an increase in the population of S-phase cells, while that of cells in G(2)/M-phase was diminished. This delay in G(2)/M-transition is caused by impaired cyclin A-CDK2 and cyclin B-CDC2 kinase activities and counteracts the accelerated S-phase entry. Cells lacking JunB show severely delayed kinetics of cyclin A mRNA expression due to the loss of proper transcriptional activation mediated via binding of JunB to the CRE element in the cyclin A promoter. Upon reintroduction of an inducible JunB-ER(TM) expression vector the cell cycle distribution and the cell cycle-associated cyclin A-CDK2 kinase activity could be restored. Thus, cyclin A is a direct transcriptional target of JunB driving cell proliferation.
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Affiliation(s)
- Sven Andrecht
- Division for Signal Transduction and Growth Control, Deutsches Krebsforschungszentrum Heidelberg, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
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36
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Beier F, LuValle P. The cyclin D1 and cyclin A genes are targets of activated PTH/PTHrP receptors in Jansen's metaphyseal chondrodysplasia. Mol Endocrinol 2002; 16:2163-73. [PMID: 12198252 DOI: 10.1210/me.2001-0103] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Jansen's metaphyseal chondrodysplasia (JMC) is an autosomal dominant disorder characterized by short-limbed dwarfism, delayed ossification, and hypercalcemia. Activating mutations in the PTH/PTHrP receptor have been identified as the molecular cause of this disorder. Although these mutations have been shown to increase cAMP accumulation, little is known about possible target genes of the downstream signaling pathways that may contribute to the pathogenesis of the disease. Here we demonstrate that JMC mutations of the PTH/PTHrP receptor induce activation of the cyclin D1 and cyclin A promoters in primary mouse chondrocytes and rat chondrosarcoma cells. Induction of cyclin D1 expression is required for stimulation of E2F-dependent transcription by mutant receptors. Activation of the cyclin D1 and cyclin A promoters requires a functional cAMP response element in both genes. Inhibition of protein kinase A or the transcription factor cAMP response element binding protein blocks the stimulation of both promoters by mutant receptors, whereas inhibition of activating transcription factor 2, c-Fos, or c-Jun has only minor effects. In summary, our data suggest that stimulation of cell cycle gene expression and cell cycle progression by mutant PTH/PTHrP receptors contribute to the pathogenesis of JMC.
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MESH Headings
- Animals
- Cell Cycle Proteins
- Chondrocytes
- Cyclic AMP Response Element-Binding Protein/metabolism
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Cyclin A/genetics
- Cyclin D1/genetics
- DNA-Binding Proteins
- E2F Transcription Factors
- Exostoses, Multiple Hereditary/genetics
- Exostoses, Multiple Hereditary/metabolism
- Gene Expression Regulation
- Humans
- Mice
- Mutation/genetics
- Promoter Regions, Genetic/genetics
- Rats
- Receptor, Parathyroid Hormone, Type 1/genetics
- Receptor, Parathyroid Hormone, Type 1/metabolism
- Receptors, Parathyroid Hormone/genetics
- Receptors, Parathyroid Hormone/metabolism
- Response Elements/genetics
- Transcription Factors/metabolism
- Transcription, Genetic
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Affiliation(s)
- Frank Beier
- Canadian Institutes of Health Research Group in Skeletal Development and Remodeling, University of Western Ontario, London, Ontario, Canada N6A 5C1.
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37
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Ahn JD, Morishita R, Kaneda Y, Lee SJ, Kwon KY, Choi SY, Lee KU, Park JY, Moon IJ, Park JG, Yoshizumi M, Ouchi Y, Lee IK. Inhibitory effects of novel AP-1 decoy oligodeoxynucleotides on vascular smooth muscle cell proliferation in vitro and neointimal formation in vivo. Circ Res 2002; 90:1325-32. [PMID: 12089071 DOI: 10.1161/01.res.0000023200.19316.d5] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Excessive proliferation of vascular smooth muscle cells (VSMCs) and neointimal formation are critical steps in the pathogenesis of atherosclerosis and restenosis after percutaneous transluminal angioplasty. In this study, we investigated the hypothesis that the activator protein-1 (AP-1) plays an important role in neointimal formation after vascular injury. A circular dumbbell AP-1 decoy oligodeoxynucleotide (CDODN) was developed as a novel therapeutic strategy for restenosis after angioplasty. This CDODN was more stable than the conventional phosphorothioate linear decoy ODN (PSODN) and maintained structural integrity on exposure to exonuclease III or serum. Transfection with AP-1 decoy ODNs strongly inhibited VSMC proliferation and migration, as well as glucose- and serum-induced expression of PCNA and cyclin A genes. Administration of AP-1 decoy ODNs in vivo using the hemagglutinating virus of Japan (HVJ)-liposome method virtually abolished neointimal formation after balloon injury to the rat carotid artery. Compared with PSODN, CDODN was more effective in inhibiting the proliferation of VSMCs in vitro and neointimal formation in vivo. Our results collectively indicate that AP-1 activation is crucial for the mediation of VSMC proliferation in response to vascular injury. Moreover, the use of stable CDODN specific for AP-1 activity in combination with the highly effective HVJ-liposome method provides a novel potential therapeutic strategy for the prevention of restenosis after angioplasty in humans.
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MESH Headings
- Angioplasty, Balloon/adverse effects
- Animals
- Base Sequence
- Binding Sites
- Carotid Stenosis/etiology
- Carotid Stenosis/pathology
- Carotid Stenosis/prevention & control
- Cell Division/drug effects
- Cell Movement/drug effects
- Cells, Cultured
- DNA, Circular/pharmacology
- DNA-Binding Proteins/metabolism
- Graft Occlusion, Vascular/prevention & control
- Humans
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiology
- Oligodeoxyribonucleotides/chemistry
- Oligodeoxyribonucleotides/metabolism
- Oligodeoxyribonucleotides/pharmacology
- Rats
- Rats, Sprague-Dawley
- Transcription Factor AP-1/antagonists & inhibitors
- Transcription Factor AP-1/physiology
- Transcription, Genetic/drug effects
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Affiliation(s)
- Jong Deok Ahn
- Department of Microbiology, Kyungpook National University, Taegu, Korea
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38
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Yates S, Rayner TE. Transcription factor activation in response to cutaneous injury: role of AP-1 in reepithelialization. Wound Repair Regen 2002; 10:5-15. [PMID: 11983002 DOI: 10.1046/j.1524-475x.2002.10902.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Reepithelialization is the process responsible for restoring an intact epidermis following cutaneous injury. A change in the activity of keratinocytes is required for reepithelialization to occur, and this is likely to be regulated by the altered expression of effector genes, mediated by transcription factors. The injury itself provides a stimulus for transcription factor activation either directly due to mechanical stress, or via paracrine mechanisms such as the release of growth factors from damaged cells. Members of the activator protein-1 family, in particular c-fos and c-jun, have been the most widely studied wound-induced transcription factors. The signal transduction pathways linking cellular injury to activator protein-1 stimulation appear to involve an increase in intracellular Ca2+ and activation of mitogen-activated protein kinases. Given that a number of genes involved in the reepithelialization of wounds are regulated by activator protein-1, a distinct role for this transcription factor in reepithelialization is beginning to emerge. This article reviews the evidence for activator protein-1 involvement in reepithelialization, with particular focus on the activation of this transcription factor in response to wounding, the second messenger/kinase pathways involved, and the modulation of downstream genes that have the capacity to regulate keratinocyte function.
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Affiliation(s)
- Samantha Yates
- Co-operative Research Centre for Tissue Growth and Repair, The University of Adelaide Department of Surgery, The Queen Elizabeth Hospital, Woodville, Australia
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39
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Wellman GC, Cartin L, Eckman DM, Stevenson AS, Saundry CM, Lederer WJ, Nelson MT. Membrane depolarization, elevated Ca(2+) entry, and gene expression in cerebral arteries of hypertensive rats. Am J Physiol Heart Circ Physiol 2001; 281:H2559-67. [PMID: 11709423 DOI: 10.1152/ajpheart.2001.281.6.h2559] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Elevated intracellular Ca(2+) ([Ca(2+)](i)) has been implicated in contractile and phenotypic changes in arterial smooth muscle during hypertension. This study examined the role of membrane potential and [Ca(2+)](i) in altered gene expression in cerebral arteries of a rat (Dahl) genetic model of salt-sensitive hypertension. Cerebral arteries from hypertensive animals (Dahl salt-sensitive) exhibited a tonic membrane depolarization of approximately 15 mV compared with normotensive (Dahl salt-resistant) animals. Consistent with this membrane depolarization, voltage-dependent K(+) currents were decreased in cerebral artery myocytes isolated from hypertensive animals. Arterial wall Ca(2+) was elevated in cerebral arteries from hypertensive animals, an effect reversed by diltiazem, a blocker of voltage-dependent Ca(2+) channels. This depolarization-induced increase in [Ca(2+)](i) was associated with increased activation of the transcription factor, cAMP response element binding protein, and increased expression of the immediate early gene c-fos, both of which are reversed by acute exposure to the voltage-dependent Ca(2+) channel blocker nisoldipine. This study provides the first information linking altered Ca(2+) handling to changes in gene expression in cerebral arteries during hypertension.
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Affiliation(s)
- G C Wellman
- Department of Pharmacology, The University of Vermont College of Medicine, Burlington, Vermont 05405, USA.
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40
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Bottazzi ME, Buzzai M, Zhu X, Desdouets C, Bréchot C, Assoian RK. Distinct effects of mitogens and the actin cytoskeleton on CREB and pocket protein phosphorylation control the extent and timing of cyclin A promoter activity. Mol Cell Biol 2001; 21:7607-16. [PMID: 11604497 PMCID: PMC99932 DOI: 10.1128/mcb.21.22.7607-7616.2001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Soluble mitogens and adhesion-dependent organization of the actin cytoskeleton are required for cells to enter S phase in fibroblasts. The induction of cyclin A is also required for S-phase entry, and we now report that distinct effects of mitogens and the actin cytoskeleton on the phosphorylation of CREB and pocket proteins regulate the extent and timing of cyclin A promoter activity, respectively. First, we show that CREB phosphorylation and binding to the cyclic AMP response element (CRE) determines the extent, but not the timing, of cyclin A promoter activity. Second, we show that pocket protein inactivation regulates the timing, but not the extent, of cyclin A promoter activity. CREB phosphorylation and CRE occupancy are regulated by soluble mitogens alone, while the phosphorylation of pocket proteins requires both mitogens and the organized actin cytoskeleton. Mechanistically, cytoskeletal integrity controls pocket protein phosphorylation by allowing for sustained ERK signaling and, thereby, the expression of cyclin D1. Our results lead to a model of cyclin A gene regulation in which mitogens play a permissive role by stimulating early G(1)-phase phosphorylation of CREB and a distinct regulatory role by cooperating with the organized actin cytoskeleton to regulate the duration of ERK signaling, the expression of cyclin D1, and the timing of pocket protein phosphorylation.
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Affiliation(s)
- M E Bottazzi
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, 19104-6084, USA
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41
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Goukassian D, Díez-Juan A, Asahara T, Schratzberger P, Silver M, Murayama T, Isner JM, Andrés V. Overexpression of p27(Kip1) by doxycycline-regulated adenoviral vectors inhibits endothelial cell proliferation and migration and impairs angiogenesis. FASEB J 2001; 15:1877-85. [PMID: 11532967 DOI: 10.1096/fj.01-0065com] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Formation of new blood vessels in the adult animal (i.e., angiogenesis) is an important event for tissue repair and for tumor growth and metastasis. Angiogenesis involves the migration and proliferation of endothelial cells. We have investigated the role of the growth suppressor p27(Kip1) (p27) on endothelial cell function in vitro and angiogenesis in vivo. We have generated Ad-TetON, a replication-deficient adenovirus that constitutively expresses the reverse tet-responsive transcriptional activator, and Ad-TRE-p27, which drives expression of p27 under the control of the tet response element. Western blot analysis demonstrated doxycycline-dependent overexpression of p27 in human umbilical vein endothelial cells (HUVECs) coinfected with Ad-TetON and Ad-TRE-p27, which resulted in a marked inhibition of DNA replication and cell migration in vitro. Inducible overexpression of p27 in cultured HUVECs inhibited the formation of tubelike structures and, when applied in a murine model of hind limb ischemia, reduced hind limb blood flow recovery and capillary density. These findings thus underscore a novel role of p27 in regulating endothelial cell migration in vitro and angiogenesis in vivo, suggesting a novel anti-angiogenic therapy based on inducible p27 overexpression.
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Affiliation(s)
- D Goukassian
- Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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42
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Díez-Juan A, Andrés V. The growth suppressor p27(Kip1) protects against diet-induced atherosclerosis. FASEB J 2001; 15:1989-95. [PMID: 11532979 DOI: 10.1096/fj.01-0130com] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The molecular basis of atherosclerosis is associated with excessive proliferation of vascular cells. Previous studies have suggested an inverse correlation between the expression of the growth suppressor p27(Kip1) (p27) and cellular proliferation within human atherosclerotic tissue. However, no causal link between diminished p27 expression and atherogenesis has been established. We investigated the effect of p27 inactivation on diet-induced atherogenesis. We find that p27-deficient mice challenged with a high-fat diet for 1 month remain normocholesterolemic and have essentially no visible atheromas. However, when generated in an apolipoprotein E-null genetic background that leads to severe hypercholesterolemia in response to the atherogenic diet, deletion of p27 enhances arterial cell proliferation (approximately fourfold) and accelerates atherogenesis (approximately sixfold) compared with apolipoprotein E-deficient mice with an intact p27 gene. Analysis of apolipoprotein E-null mice bearing only one p27 allele inactivated reveals that a moderate decrease in p27 protein expression in the setting of hypercholesterolemia is sufficient to predispose to atherogenesis. Thus, our study establishes a molecular link between decreased p27 protein expression and atherogenesis in hypercholesterolemic animals.
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Affiliation(s)
- A Díez-Juan
- Instituto de Biomedicina de Valencia (IBV-CSIC), Spanish Council for Scientific Research, C/Jaime Roig 11, 46010-Valencia, Spain
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43
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Goukassian D, Sanz-González SM, Pérez-Roger I, Font de Mora J, Ureña J, Andrés V. Inhibition of the cyclin D1/E2F pathway by PCA-4230, a potent repressor of cellular proliferation. Br J Pharmacol 2001; 132:1597-605. [PMID: 11264255 PMCID: PMC1572687 DOI: 10.1038/sj.bjp.0703945] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
1. Tight control of cellular growth is essential to ensure normal tissue patterning and prevent pathological responses. Excessive vascular smooth muscle cell (VSMC) proliferation is associated with the pathophysiology of atherosclerosis and restenosis post-angioplasty. Thus, drug targeting of pathological VSMC growth may be a suitable therapeutic intervention in vascular proliferative diseases. 2. In the present study, we investigated the mechanisms underlying VSMC growth arrest induced by the pharmacological agent PCA-4230. Addition of PCA-4230 to cultured VSMCs blocked the induction of cyclin D1 and cyclin A expression normally seen in serum-restimulated cells. Moreover, PCA-4230 inhibited cyclin-dependent kinase 2 (CDK2) activity and abrogated hyperphosphorylation of the retinoblastoma (Rb) gene product. Similarly, PCA-4230-dependent growth arrest of transformed cell lines correlated with reduced level of cyclin D1 protein and inhibition of CDK2 activity. Consistent with these findings, PCA-4230 repressed serum-inducible cyclin A promoter activity, and overexpression of either cyclin D1 or E2F1 efficiently circumvented this inhibitory effect. Importantly, adenovirus-mediated overexpression of E2F1 restored S-phase entry in PCA-4230-treated VSMCs, demonstrating that PCA-4230 represses cyclin A gene expression and VSMC growth via inhibition of the cyclin D1/E2F pathway. 3. Because of its ability to inhibit the growth of human VSMCs and transformed cell lines, future studies are warranted to assess whether PCA-4230 may be a suitable therapeutic intervention for the treatment of hyperproliferative disorders, including cardiovascular disease and cancer.
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MESH Headings
- Animals
- Carrier Proteins
- Cell Cycle Proteins/drug effects
- Cell Cycle Proteins/metabolism
- Cell Division/drug effects
- Cells, Cultured
- Cyclin A/genetics
- Cyclin D1/metabolism
- Cyclin D1/physiology
- DNA-Binding Proteins
- Dihydropyridines/pharmacology
- Dose-Response Relationship, Drug
- E2F Transcription Factors
- E2F1 Transcription Factor
- Humans
- Luciferases/drug effects
- Luciferases/genetics
- Luciferases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Promoter Regions, Genetic/genetics
- Rats
- Rats, Inbred F344
- Recombinant Fusion Proteins/drug effects
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Retinoblastoma-Binding Protein 1
- S Phase
- Signal Transduction/drug effects
- Time Factors
- Transcription Factor DP1
- Transcription Factors/metabolism
- Transcription Factors/physiology
- Tumor Cells, Cultured
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Affiliation(s)
- D Goukassian
- Department of Dermatology, Boston University School of Medicine, Boston, Massachusetts, MA 02118, USA
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44
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Andrés V, Ureña J, Poch E, Chen D, Goukassian D. Role of Sp1 in the induction of p27 gene expression in vascular smooth muscle cells in vitro and after balloon angioplasty. Arterioscler Thromb Vasc Biol 2001; 21:342-7. [PMID: 11231912 DOI: 10.1161/01.atv.21.3.342] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
-The abnormal proliferation of vascular smooth muscle cells (VSMCs) plays an important role in atherosclerosis and restenosis. Although several studies have implicated the growth inhibitory protein p27(Kip1) (p27) in the control of myocyte growth and hypertrophy, little is known about the molecular mechanisms that regulate p27 expression in the cardiovascular system. In the present study, we demonstrate the interaction of the transcription factor Sp1 with 2 GC-rich sequences within the p27 promoter in cultured VSMCs. Importantly, point mutations that disrupted Sp1 binding markedly reduced p27 promoter activity, demonstrating that Sp1 is required for efficient p27 gene transcription in cultured VSMCs. Because p27 expression is upregulated after balloon angioplasty, we investigated Sp1 expression and activity in control and balloon-injured rat carotid arteries to assess the role of Sp1 as a physiological regulator of p27 expression. Although immunohistochemical analysis disclosed Sp1 protein expression in both control and balloon-injured arteries, a high level of Sp1 DNA-binding activity was found only in response to balloon angioplasty. Collectively, these results demonstrate that Sp1 is essential for maximum p27 promoter activity in VSMCs and suggest that posttranslational induction of Sp1 DNA-binding activity contributes to the induction of p27 expression and VSMC growth arrest at late time points after balloon angioplasty.
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MESH Headings
- Angioplasty, Balloon
- Animals
- Binding Sites
- Carotid Arteries/metabolism
- Cell Cycle Proteins
- Cells, Cultured
- Cyclin-Dependent Kinase Inhibitor p27
- DNA/genetics
- DNA/metabolism
- GC Rich Sequence/genetics
- Gene Expression Regulation
- Male
- Microtubule-Associated Proteins/genetics
- Microtubule-Associated Proteins/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Promoter Regions, Genetic/genetics
- Protein Binding
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred F344
- Rats, Sprague-Dawley
- Sp1 Transcription Factor/metabolism
- Sp1 Transcription Factor/physiology
- Tumor Suppressor Proteins
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Affiliation(s)
- V Andrés
- Unit of Vascular Biology, Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas, Valencia, Spain.
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45
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Stevenson AS, Cartin L, Wellman TL, Dick MH, Nelson MT, Lounsbury KM. Membrane depolarization mediates phosphorylation and nuclear translocation of CREB in vascular smooth muscle cells. Exp Cell Res 2001; 263:118-30. [PMID: 11161711 DOI: 10.1006/excr.2000.5107] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diverse signals have the potential to modulate gene transcription through the Ca2+ and cAMP response element binding protein (CREB) in vascular smooth muscle cells (VSMCs). A key step in the transmission of these signals is import into the nucleus. Here, we provide evidence that the Ran GTPase, which regulates nuclear import, exerts different regulation over PDGF-BB, Ca2+, and cAMP signaling to CREB in VSMCs. PDGF-BB, membrane depolarization, and forskolin increased levels of activated CREB (P-CREB) and c-fos in VSMCs and intact aorta. The calcium channel antagonist nimodipine reduced the level of P-CREB stimulated by membrane depolarization, but not by PDGF-BB or forskolin. Block of Ran-mediated nuclear import, by wheat germ agglutinin or an inactivating Ran mutant (T24N Ran), significantly reduced nuclear P-CREB in response to PDGF-BB or membrane depolarization, but enhanced levels of P-CREB in response to forskolin. Contrary to expectation, block of nuclear import led to the appearance of P-CREB in the cytoplasm after depolarization. Furthermore, blocking nuclear export with leptomycin B reduced P-CREB stimulation by both depolarization and PDGF-BB. These results suggest that translocation of CREB between the nucleus and the cytoplasm provides an important role in CREB activating pathways in VSMCs.
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Affiliation(s)
- A S Stevenson
- Department of Pharmacology, University of Vermont, Burlington, Vermont 05405, USA
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46
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Sekiguchi K, Kurabayashi M, Oyama Y, Aihara Y, Tanaka T, Sakamoto H, Hoshino Y, Kanda T, Yokoyama T, Shimomura Y, Iijima H, Ohyama Y, Nagai R. Homeobox protein Hex induces SMemb/nonmuscle myosin heavy chain-B gene expression through the cAMP-responsive element. Circ Res 2001; 88:52-8. [PMID: 11139473 DOI: 10.1161/01.res.88.1.52] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Recent studies have shown that the homeobox gene Hex plays an important role in inducing differentiation of vascular endothelial cells. In this study, we examined the expression of Hex in vascular smooth muscle cells (VSMCs) in vitro and in vivo. Immunohistochemistry showed a marked induction of Hex protein in neointimal VSMCs after balloon injury in rat aorta. Western and reverse transcriptase-polymerase chain reaction analyses demonstrated that Hex was abundantly expressed in cultured VSMCs, whereas it was undetectable in other cell types or in normal aorta. The expression pattern of Hex was similar to that of SMemb/NMHC-B, a nonmuscle isoform of myosin heavy chain that we have previously reported to be a molecular marker of dedifferentiated VSMCs. We next examined the role of Hex in SMemb gene transcription. Promoter analysis demonstrated that the sequence identical to consensus cAMP-responsive element (CRE) located at -481 of the SMemb promoter was critical for Hex responsiveness. Mutant Hex expression vector, which lacks the homeodomain, failed to stimulate SMemb gene transcription, suggesting the requirement of the homeodomain for its transactivation. Elecrophoretic mobility shift assay showed that Hex binds to a consensus binding sequence for homeobox proteins, but not to CRE. Cotransfection of protein kinase A expression vector increased the ability of Hex to stimulate SMemb promoter activity in a CRE-dependent manner. Overexpression of CRE binding protein (CREB), but not Mut-CREB which contains mutation at Ser133, strongly activated Hex-induced SMemb promoter activity. These results suggest that Hex mediates transcriptional induction of the SMemb/NMHC-B gene via its homeodomain, and Hex can function as a transcriptional modulator of CRE-dependent transcription in VSMCs.
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MESH Headings
- 3T3 Cells
- Animals
- Animals, Newborn
- Base Sequence
- Binding Sites/genetics
- Blotting, Western
- COS Cells
- Catheterization
- Cattle
- Cell Line
- Cells, Cultured
- Cyclic AMP/metabolism
- Cyclic AMP Response Element-Binding Protein/genetics
- Cyclic AMP Response Element-Binding Protein/metabolism
- Gene Expression Regulation
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Luciferases/genetics
- Luciferases/metabolism
- Male
- Mice
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Mutation
- Myosin Heavy Chains/genetics
- Myosin Heavy Chains/metabolism
- Nonmuscle Myosin Type IIB
- Promoter Regions, Genetic/genetics
- Protein Binding
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Response Elements/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Deletion
- Transcription Factors
- Transcriptional Activation
- Tunica Intima/metabolism
- Tunica Intima/pathology
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Affiliation(s)
- K Sekiguchi
- Second Department of Internal Medicine, Gunma University School of Medicine, Maebashi, Japan
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47
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Abstract
Reactive oxygen intermediates (ROIs) in low concentration, as released permanently by nonphagocytic cells, possess important functions in inter- and intracellular signalling. They lead to alterations in the phosphorylation pattern followed by gene activation, including the expression of proto-oncogenes. Redox-sensitive sites in membrane molecules may trigger adhesion and chemotaxis or open ion channels and activate transport processes across the cytoplasma membrane. ROIs shift the ratio of cyclic GMP to cyclic AMP giving signals to proliferation and differentiation processes. Senescence, apoptosis, and cell death can also be modulated by ROIs, depending on concentration and cell type.
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Affiliation(s)
- B Meier
- Tierärztliche Hochschule, Hannover, Federal Republic of Germany
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48
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Stula M, Orzechowski HD, Gschwend S, Vetter R, von Harsdorf R, Dietz R, Paul M. Influence of sustained mechanical stress on Egr-1 mRNA expression in cultured human endothelial cells. Mol Cell Biochem 2000; 210:101-8. [PMID: 10976763 DOI: 10.1023/a:1007126218740] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Restenosis after initially successful balloon angioplasty of coronary artery stenosis remains a major problem in clinical cardiology. Previous studies have identified pathogenetic factors which trigger cell proliferation and vascular remodeling ultimately leading to restenosis. Since there is evidence that endothelial cells adjacent to the angioplasty wound area synthesize factors which may initiate this process, we investigated the effects of mechanical stimulation on endothelial gene expression in vitro and focussed on the influence of sustained mechanical stress on expression of immediate early genes which have previously been shown to be induced in the vascular wall in vivo. Primary cultured human umbilical vein endothelial cells (HUVEC) and the human endothelial cell line EA.hy 926 were plated on collagen-coated silicone membranes and subjected to constant longitudinal stress of approximately 20% for 10 min to 6 h. Total RNA was isolated and the expression of the immediate early genes c-Fos and Egr-1 was studied by Northern blot analysis. We found a rapid upregulation c-Fos and Egr-1 mRNA which started at 10 min and reached its maxima at 30 min. HUVEC lost most of their stretch response after the third passage whereas immediate early gene expression was constantly in EA.hy 926 cells. Using specific inhibitors we investigated the contribution of several signal transduction pathways to stretch-activated Egr-1 mRNA expression. We found significant suppression of stretch-induced Egr-1 mRNA expression by protein kinase C (PKC) inhibition (p < 0.05) and by calcium depletion (EA.hy 926, p < 0.05; HUVEC, p = 0.063). No effect on stretch-activated Egr-1 mRNA expression was detected by inhibition of protein kinase A, blockade of stretch-activated cation channels or inhibition of microtubule synthesis. We conclude that sustained mechanical strain induces Egr-1 mRNA expression by PKC- and calcium-dependent mechanisms.
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Affiliation(s)
- M Stula
- Institute of Clinical Pharmacology and Toxicology, Benjamin Franklin Medical Center, Freie Universität Berlin, Germany
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49
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Beier F, Taylor AC, LuValle P. Activating transcription factor 2 is necessary for maximal activity and serum induction of the cyclin A promoter in chondrocytes. J Biol Chem 2000; 275:12948-53. [PMID: 10777595 DOI: 10.1074/jbc.275.17.12948] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Endochondral bone growth is regulated through the proliferation and differentiation of growth plate chondrocytes. Mice deficient for the activating transcription factor 2 (ATF-2) gene show reduced proliferation of chondrocytes. Here we demonstrate that the cyclin A gene is a target of ATF-2 in chondrocytes. Serum stimulation of chondrogenic rat chondrosarcoma cells induces cyclin A expression. A cyclic AMP response element (CRE) is necessary for optimal activity and serum inducibility of the cyclin A promoter and confers regulation by ATF-2. Phosphorylation and activity of ATF-2 are enhanced dramatically upon serum stimulation of rat chondrosarcoma cells. Mutation of the CRE or overexpression of dominant-negative ATF-2 inhibits serum induction of the cyclin A promoter. Chondrocytes from ATF-2-deficient mice display reduced and delayed induction of cyclin A upon serum stimulation. The ATF-2-related transcription factor CRE-binding protein contributes to the activity of the cyclin A CRE in chondrocytes, whereas c-Jun and c-Fos regulate the promoter independently of the CRE. Our data suggest that the reduction in cyclin A levels in chondrocytes from ATF-2-deficient mice contributes to their phenotype of reduced chondrocyte proliferation and dwarfism.
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Affiliation(s)
- F Beier
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
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50
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Baetta R, Soma M, De-Fraja C, Comparato C, Teruzzi C, Magrassi L, Cattaneo E. Upregulation and activation of Stat6 precede vascular smooth muscle cell proliferation in carotid artery injury model. Arterioscler Thromb Vasc Biol 2000; 20:931-9. [PMID: 10764656 DOI: 10.1161/01.atv.20.4.931] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The role of signal transducers and activators of transcription (STAT) proteins in modulating proliferation and differentiation of various cell types in the hematopoietic system and the central nervous system has been well established. In contrast, the pathophysiological role of these proteins in vascular proliferative diseases has remained unproven, despite in vitro observations emphasizing the involvement of the STAT system in mediating vascular smooth muscle cell (VSMC) proliferation. On the basis of our previous observations demonstrating the occurrence of a specific modulation of Stat6 protein during the proliferative, migratory, and differentiation phases of the developing brain, we investigated whether Stat6 protein is present and modulated in arterial tissue challenged by perivascular injury. The time course of expression and localization of Stat6 after arterial injury was analyzed by immunohistochemistry, Western blot analysis, and confocal microscopy. Six hours after injury, the expression of Stat6 was markedly increased. This overexpression preceded the onset of VSMC proliferation and was downregulated starting from 7 days after injury, coincident with the decline of VSMC proliferation. Moreover, early after injury, Stat6 was predominantly localized at the nuclear level, denoting its functional activation. Conversely, Stat6 staining at later time points was largely cytosolic, suggesting silencing effects of this signaling pathway. These data indicate that Stat6 signaling may contribute to the modifications of gene expression underlying VSMC activation in the context of acute vascular proliferative diseases.
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Affiliation(s)
- R Baetta
- Institute of Pharmacological Sciences, University of Milan, Milan, Italy.
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