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Gonzalez-Llerena JL, Espinosa-Rodriguez BA, Treviño-Almaguer D, Mendez-Lopez LF, Carranza-Rosales P, Gonzalez-Barranco P, Guzman-Delgado NE, Romo-Mancillas A, Balderas-Renteria I. Cordycepin Triphosphate as a Potential Modulator of Cellular Plasticity in Cancer via cAMP-Dependent Pathways: An In Silico Approach. Int J Mol Sci 2024; 25:5692. [PMID: 38891880 PMCID: PMC11171877 DOI: 10.3390/ijms25115692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/14/2024] [Accepted: 05/21/2024] [Indexed: 06/21/2024] Open
Abstract
Cordycepin, or 3'-deoxyadenosine, is an adenosine analog with a broad spectrum of biological activity. The key structural difference between cordycepin and adenosine lies in the absence of a hydroxyl group at the 3' position of the ribose ring. Upon administration, cordycepin can undergo an enzymatic transformation in specific tissues, forming cordycepin triphosphate. In this study, we conducted a comprehensive analysis of the structural features of cordycepin and its derivatives, contrasting them with endogenous purine-based metabolites using chemoinformatics and bioinformatics tools in addition to molecular dynamics simulations. We tested the hypothesis that cordycepin triphosphate could bind to the active site of the adenylate cyclase enzyme. The outcomes of our molecular dynamics simulations revealed scores that are comparable to, and superior to, those of adenosine triphosphate (ATP), the endogenous ligand. This interaction could reduce the production of cyclic adenosine monophosphate (cAMP) by acting as a pseudo-ATP that lacks a hydroxyl group at the 3' position, essential to carry out nucleotide cyclization. We discuss the implications in the context of the plasticity of cancer and other cells within the tumor microenvironment, such as cancer-associated fibroblast, endothelial, and immune cells. This interaction could awaken antitumor immunity by preventing phenotypic changes in the immune cells driven by sustained cAMP signaling. The last could be an unreported molecular mechanism that helps to explain more details about cordycepin's mechanism of action.
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Affiliation(s)
- Jose Luis Gonzalez-Llerena
- Laboratory of Molecular Pharmacology and Biological Models, School of Chemistry, Autonomous University of Nuevo Leon, San Nicolas de los Garza 66451, Mexico; (J.L.G.-L.); (B.A.E.-R.); (D.T.-A.); (P.G.-B.)
- Center for Research on Nutrition and Public Health, School of Public Health and Nutrition, Autonomous University of Nuevo Leon, Monterrey 66460, Mexico;
| | - Bryan Alejandro Espinosa-Rodriguez
- Laboratory of Molecular Pharmacology and Biological Models, School of Chemistry, Autonomous University of Nuevo Leon, San Nicolas de los Garza 66451, Mexico; (J.L.G.-L.); (B.A.E.-R.); (D.T.-A.); (P.G.-B.)
| | - Daniela Treviño-Almaguer
- Laboratory of Molecular Pharmacology and Biological Models, School of Chemistry, Autonomous University of Nuevo Leon, San Nicolas de los Garza 66451, Mexico; (J.L.G.-L.); (B.A.E.-R.); (D.T.-A.); (P.G.-B.)
| | - Luis Fernando Mendez-Lopez
- Center for Research on Nutrition and Public Health, School of Public Health and Nutrition, Autonomous University of Nuevo Leon, Monterrey 66460, Mexico;
| | - Pilar Carranza-Rosales
- Laboratory of Cell Biology, Northeast Biomedical Research Center, Mexican Social Security Institute, Monterrey 64720, Mexico;
| | - Patricia Gonzalez-Barranco
- Laboratory of Molecular Pharmacology and Biological Models, School of Chemistry, Autonomous University of Nuevo Leon, San Nicolas de los Garza 66451, Mexico; (J.L.G.-L.); (B.A.E.-R.); (D.T.-A.); (P.G.-B.)
| | - Nancy Elena Guzman-Delgado
- Health Research Division, High Specialty Medical Unit, Cardiology Hospital N. 34. Mexican Social Security Institute, Monterrey 64360, Mexico;
| | - Antonio Romo-Mancillas
- Computer Aided Drug Design and Synthesis Group, School of Chemistry, Autonomous University of Queretaro, Queretaro 76010, Mexico
| | - Isaias Balderas-Renteria
- Laboratory of Molecular Pharmacology and Biological Models, School of Chemistry, Autonomous University of Nuevo Leon, San Nicolas de los Garza 66451, Mexico; (J.L.G.-L.); (B.A.E.-R.); (D.T.-A.); (P.G.-B.)
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2
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Parsons EC, Hoffmann R, Baillie GS. Revisiting the roles of cAMP signalling in the progression of prostate cancer. Biochem J 2023; 480:1599-1614. [PMID: 37830741 PMCID: PMC10586777 DOI: 10.1042/bcj20230297] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/29/2023] [Accepted: 10/05/2023] [Indexed: 10/14/2023]
Abstract
Prostate cancer is one of the most common cancers in men and one of the top causes of death in men worldwide. Development and function of both normal prostate cells and early-stage prostate cancer cells are dependent on the cross-talk between androgen signalling systems and a variety of other transduction pathways which drive differentiation of these cells towards castration-resistance. One such signalling pathway is the ubiquitous cAMP signalling axis which functions to activate spatially restricted pools of cAMP effectors such as protein kinase A (PKA). The importance of both PKA and cAMP in the development of prostate cancer, and their interactions with the androgen receptor, were the focus of a review by Merkle and Hoffmann in 2010. In this updated review, we revisit this topic with analysis of current PKA-related prostate cancer literature and introduce novel information on the relevance of another cAMP effector, the exchange protein directly activated by cAMP (EPAC).
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Affiliation(s)
- Emma C. Parsons
- School of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Bearsden, Glasgow G61 1QH, U.K
| | - Ralf Hoffmann
- Oncology, Philips Research Eindhoven, High Tech Campus 34, 5656 AE Eindhoven, The Netherlands
- School of Cardiovascular & Metabolic Health, University of Glasgow, University Avenue, Glasgow G12 8QQ, U.K
| | - George S. Baillie
- School of Cardiovascular & Metabolic Health, University of Glasgow, University Avenue, Glasgow G12 8QQ, U.K
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3
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Dehghanian M, Yarahmadi G, Sandoghsaz RS, Khodadadian A, Shamsi F, Vahidi Mehrjardi MY. Evaluation of Rap1GAP and EPAC1 Gene Expression in Endometriosis Disease. Adv Biomed Res 2023; 12:101. [PMID: 37288024 PMCID: PMC10241619 DOI: 10.4103/abr.abr_86_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/30/2022] [Accepted: 07/03/2022] [Indexed: 06/09/2023] Open
Abstract
Background Endometriosis is a female reproductive system disease in which the endometrial tissue is found in other women's organs. Various factors are effective in the development of endometriosis, and because of the interaction of genetics and environmental factors, this disease is a multi-factorial disease. MAPK/ERK and PI3K/Akt/mTOR pathways are activated by growth factors and steroid hormones and are known as two important pathways involved in the processes of growth, proliferation, and survival of endometriosis cells. Raps, monomeric GTPase of the Ras family, are able to activate these pathways independent of Ras. The goal of our study was to evaluate the expression level of Rap1GAP and EPAC1 genes as two important RapGAPs (GTPase-activating proteins) and RapGEFs (guanine nucleotide exchange factors), respectively, in endometriosis tissues and normal endometrium tissues. Materials and Methods In this study, 15 samples of women without signs of endometriosis were taken as control samples. Fifteen ectopic and 15 eutopic samples were taken from women with endometriosis using laparoscopic surgery. The expression of EPAC1 and Rap1GAP genes was investigated by the real-time polymerase chain reaction technique, and the results were analyzed by one-way ANOVA test. Results EPAC1 upregulated significantly in ectopic tissues compared to eutopic and control tissues. Rap1GAP expression was lower in ectopic tissues compared to control and eutopic tissues. Conclusions Based on these results, it may be concluded that changes in the expression of the Rap1GAP and Epca1 genes may play a role in the pathways involved in the pathogenesis, displacement, and migration of endometriosis cells.
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Affiliation(s)
- Mehran Dehghanian
- Department of Medical Genetics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
- Abortion Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Ghafour Yarahmadi
- Department of Medical Genetics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
- Abortion Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Reyhaneh Sadat Sandoghsaz
- Abortion Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Ali Khodadadian
- Department of Medical Genetics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Farimah Shamsi
- Department of Biostatistics and Epidemiology, Center for Healthcare Data Modeling, School of Pulic Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Mohammad Yahya Vahidi Mehrjardi
- Research Center for Food Hygiene and Safety, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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Belyaev GP, Vyshtakalyuk AB, Parfenov AA, Shashin MS, Galyametdinova IV, Semenov VE, Zobov VV. Comparative assessment of hepatoprotective properties of some “doubled” 4,6-dimethyl-1,2-dihydro-1-(2-hydroxyethyl)pyrimidin-2-one derivatives. Russ Chem Bull 2022. [DOI: 10.1007/s11172-022-3699-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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5
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Krishnan A, Bhasker AI, Singh MK, Rodriguez CI, Castro-Pérez E, Altameemi S, Lares M, Khan H, Ndiaye M, Ahmad N, Schieke SM, Setaluri V. EPAC Regulates Melanoma Growth by Stimulating mTORC1 Signaling and Loss of EPAC Signaling Dependence Correlates with Melanoma Progression. Mol Cancer Res 2022; 20:1548-1560. [PMID: 35834616 PMCID: PMC9532357 DOI: 10.1158/1541-7786.mcr-22-0026] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 06/02/2022] [Accepted: 07/08/2022] [Indexed: 11/16/2022]
Abstract
Exchange proteins directly activated by cAMP (EPAC) belong to a family of RAP guanine nucleotide exchange factors (RAPGEF). EPAC1/2 (RAPGEF3/4) activates RAP1 and the alternative cAMP signaling pathway. We previously showed that the differential growth response of primary and metastatic melanoma cells to cAMP is mediated by EPAC. However, the mechanisms responsible for this differential response to EPAC signaling are not understood. In this study, we show that pharmacologic inhibition or siRNA-mediated knockdown of EPAC selectively inhibits the growth and survival of primary melanoma cells by downregulation of cell-cycle proteins and inhibiting the cell-cycle progression independent of ERK1/2 phosphorylation. EPAC inhibition results in upregulation of AKT phosphorylation but a downregulation of mTORC1 activity and its downstream effectors. We also show that EPAC regulates both glycolysis and oxidative phosphorylation, and production of mitochondrial reactive oxygen species, preferentially in primary melanoma cells. Employing a series of genetically matched primary and lymph node metastatic (LNM) melanoma cells, and distant organ metastatic melanoma cells, we show that the LNM and metastatic melanoma cells become progressively less responsive and refractory to EPAC inhibition suggesting loss of dependency on EPAC signaling correlates with melanoma progression. Analysis of The Cancer Genome Atlas dataset showed that lower RAPGEF3, RAPGEF4 mRNA expression in primary tumor is a predictor of better disease-free survival of patients diagnosed with primary melanoma suggesting that EPAC signaling facilitates tumor progression and EPAC is a useful prognostic marker. These data highlight EPAC signaling as a potential target for prevention of melanoma progression. IMPLICATIONS This study establishes loss of dependency on EPAC-mTORC1 signaling as hallmark of primary melanoma evolution and targeting this escape mechanism is a promising strategy for metastatic melanoma.
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Affiliation(s)
- Aishwarya Krishnan
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Aishwarya I. Bhasker
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Mithalesh K. Singh
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Carlos. I. Rodriguez
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Edgardo Castro-Pérez
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Sarah Altameemi
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Marcos Lares
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Hamidullah Khan
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Mary Ndiaye
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705
| | - Stefan M. Schieke
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705
| | - Vijayasaradhi Setaluri
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705
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6
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Pan Y, Liu J, Ren J, Luo Y, Sun X. Epac: A Promising Therapeutic Target for Vascular Diseases: A Review. Front Pharmacol 2022; 13:929152. [PMID: 35910387 PMCID: PMC9330031 DOI: 10.3389/fphar.2022.929152] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 06/14/2022] [Indexed: 11/13/2022] Open
Abstract
Vascular diseases affect the circulatory system and comprise most human diseases. They cause severe symptoms and affect the quality of life of patients. Recently, since their identification, exchange proteins directly activated by cAMP (Epac) have attracted increasing scientific interest, because of their role in cyclic adenosine monophosphate (cAMP) signaling, a well-known signal transduction pathway. The role of Epac in cardiovascular disease and cancer is extensively studied, whereas their role in kidney disease has not been comprehensively explored yet. In this study, we aimed to review recent studies on the regulatory effects of Epac on various vascular diseases, such as cardiovascular disease, cerebrovascular disease, and cancer. Accumulating evidence has shown that both Epac1 and Epac2 play important roles in vascular diseases under both physiological and pathological conditions. Additionally, there has been an increasing focus on Epac pharmacological modulators. Therefore, we speculated that Epac could serve as a novel therapeutic target for the treatment of vascular diseases.
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Affiliation(s)
- Yunfeng Pan
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Efficacy Evaluation of Chinese Medicine Against Glycolipid Metabolic Disorders, State Administration of Traditional Chinese Medicine, Beijing, China
| | - Jia Liu
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Jiahui Ren
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Efficacy Evaluation of Chinese Medicine Against Glycolipid Metabolic Disorders, State Administration of Traditional Chinese Medicine, Beijing, China
| | - Yun Luo
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Efficacy Evaluation of Chinese Medicine Against Glycolipid Metabolic Disorders, State Administration of Traditional Chinese Medicine, Beijing, China
- *Correspondence: Yun Luo, ; Xiaobo Sun,
| | - Xiaobo Sun
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Efficacy Evaluation of Chinese Medicine Against Glycolipid Metabolic Disorders, State Administration of Traditional Chinese Medicine, Beijing, China
- *Correspondence: Yun Luo, ; Xiaobo Sun,
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7
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Guo R, Liu T, Shasaltaneh MD, Wang X, Imani S, Wen Q. Targeting Adenylate Cyclase Family: New Concept of Targeted Cancer Therapy. Front Oncol 2022; 12:829212. [PMID: 35832555 PMCID: PMC9271773 DOI: 10.3389/fonc.2022.829212] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 05/26/2022] [Indexed: 12/18/2022] Open
Abstract
The adenylate cyclase (ADCY) superfamily is a group of glycoproteins regulating intracellular signaling. ADCYs act as key regulators in the cyclic adenosine monophosphate (cAMP) signaling pathway and are related to cell sensitivity to chemotherapy and ionizing radiation. Many members of the superfamily are detectable in most chemoresistance cases despite the complexity and unknownness of the specific mechanism underlying the role of ADCYs in the proliferation and invasion of cancer cells. The overactivation of ADCY, as well as its upstream and downstream regulators, is implicated as a major potential target of novel anticancer therapies and markers of exceptional responders to chemotherapy. The present review focuses on the oncogenic functions of the ADCY family and emphasizes the possibility of the mediating roles of deleterious nonsynonymous single nucleotide polymorphisms (nsSNPs) in ADCY as a prognostic therapeutic target in modulating resistance to chemotherapy and immunotherapy. It assesses the mediating roles of ADCY and its counterparts as stress regulators in reprogramming cancer cell metabolism and the tumor microenvironment. Additionally, the well-evaluated inhibitors of ADCY-related signaling, which are under clinical investigation, are highlighted. A better understanding of ADCY-induced signaling and deleterious nsSNPs (p.E1003K and p.R1116C) in ADCY6 provides new opportunities for developing novel therapeutic strategies in personalized oncology and new approaches to enhance chemoimmunotherapy efficacy in treating various cancers.
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Affiliation(s)
- Rui Guo
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Tian Liu
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | | | - Xuan Wang
- China Regional Research Center, International Centre for Genetic Engineering and Biotechnology Taizhou, Jiangsu, China
| | - Saber Imani
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
- China Regional Research Center, International Centre for Genetic Engineering and Biotechnology Taizhou, Jiangsu, China
- *Correspondence: Saber Imani, ; QingLian Wen,
| | - QingLian Wen
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
- *Correspondence: Saber Imani, ; QingLian Wen,
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8
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Ahmed MB, Alghamdi AAA, Islam SU, Lee JS, Lee YS. cAMP Signaling in Cancer: A PKA-CREB and EPAC-Centric Approach. Cells 2022; 11:cells11132020. [PMID: 35805104 PMCID: PMC9266045 DOI: 10.3390/cells11132020] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/17/2022] [Accepted: 06/23/2022] [Indexed: 02/01/2023] Open
Abstract
Cancer is one of the most common causes of death globally. Despite extensive research and considerable advances in cancer therapy, the fundamentals of the disease remain unclear. Understanding the key signaling mechanisms that cause cancer cell malignancy may help to uncover new pharmaco-targets. Cyclic adenosine monophosphate (cAMP) regulates various biological functions, including those in malignant cells. Understanding intracellular second messenger pathways is crucial for identifying downstream proteins involved in cancer growth and development. cAMP regulates cell signaling and a variety of physiological and pathological activities. There may be an impact on gene transcription from protein kinase A (PKA) as well as its downstream effectors, such as cAMP response element-binding protein (CREB). The position of CREB downstream of numerous growth signaling pathways implies its oncogenic potential in tumor cells. Tumor growth is associated with increased CREB expression and activation. PKA can be used as both an onco-drug target and a biomarker to find, identify, and stage tumors. Exploring cAMP effectors and their downstream pathways in cancer has become easier using exchange protein directly activated by cAMP (EPAC) modulators. This signaling system may inhibit or accelerate tumor growth depending on the tumor and its environment. As cAMP and its effectors are critical for cancer development, targeting them may be a useful cancer treatment strategy. Moreover, by reviewing the material from a distinct viewpoint, this review aims to give a knowledge of the impact of the cAMP signaling pathway and the related effectors on cancer incidence and development. These innovative insights seek to encourage the development of novel treatment techniques and new approaches.
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Affiliation(s)
- Muhammad Bilal Ahmed
- BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea; (M.B.A.); (J.-S.L.)
| | | | - Salman Ul Islam
- Department of Pharmacy, Cecos University, Peshawar, Street 1, Sector F 5 Phase 6 Hayatabad, Peshawar 25000, Pakistan;
| | - Joon-Seok Lee
- BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea; (M.B.A.); (J.-S.L.)
| | - Young-Sup Lee
- BK21 FOUR KNU Creative BioResearch Group, School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 41566, Korea; (M.B.A.); (J.-S.L.)
- Correspondence: ; Tel.: +82-53-950-6353; Fax: +82-53-943-2762
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9
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The Role of Neuropeptide-Stimulated cAMP-EPACs Signalling in Cancer Cells. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27010311. [PMID: 35011543 PMCID: PMC8746471 DOI: 10.3390/molecules27010311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/23/2021] [Accepted: 12/27/2021] [Indexed: 02/06/2023]
Abstract
Neuropeptides are autocrine and paracrine signalling factors and mainly bind to G protein-coupled receptors (GPCRs) to trigger intracellular secondary messenger release including adenosine 3′, 5′-cyclic monophosphate (cAMP), thus modulating cancer progress in different kind of tumours. As one of the downstream effectors of cAMP, exchange proteins directly activated by cAMP (EPACs) play dual roles in cancer proliferation and metastasis. More evidence about the relationship between neuropeptides and EPAC pathways have been proposed for their potential role in cancer development; hence, this review focuses on the role of neuropeptide/GPCR system modulation of cAMP/EPACs pathways in cancers. The correlated downstream pathways between neuropeptides and EPACs in cancer cell proliferation, migration, and metastasis is discussed to glimmer the direction of future research.
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10
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Yang Y, Xiang P, Chen Q, Luo Y, Wang H, Li H, Yang L, Hu C, Zhang J, Li Y, Xia H, Chen Z, Yang J. The imbalance of PGD2-DPs pathway is involved in the type 2 diabetes brain injury by regulating autophagy. Int J Biol Sci 2021; 17:3993-4004. [PMID: 34671214 PMCID: PMC8495389 DOI: 10.7150/ijbs.60149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 09/07/2021] [Indexed: 12/17/2022] Open
Abstract
Prostaglandin D2 (PGD2) is the most abundant prostaglandin in the brain, but its involvement in brain damage caused by type 2 diabetes (T2D) has not been reported. In the present study, we found that increased PGD2 content is related to the inhibition of autophagy, which aggravates brain damage in T2D, and may be involved in the imbalanced expression of the corresponding PGD2 receptors DP1 and DP2. We demonstrated that DP2 inhibited autophagy and promotedT2D-induced brain damage by activating the PI3K/AKT/mTOR pathway, whereas DP1enhanced autophagy and amelioratedT2D brain damage by activating the cAMP/PKA pathway. In a T2D rat model, DP1 expression was decreased, and DP2 expression was increased; therefore, the imbalance in PGD2-DPs may be involved in T2D brain damage through the regulation of autophagy. However, there have been no reports on whether PKA can directly inhibit mTOR. The PKA catalytic subunit (PKA-C) has three subtypes (α, β and γ), and γ is not expressed in the brain. Subsequently, we suggested that PKA could directly interact with mTOR through PKA-C(α) and PKA-C(β). Our results suggest that the imbalance in PGD2-DPs is related to changes in autophagy levels in T2D brain damage, and PGD2 is involved in T2D brain damage by promoting autophagy via DP1-PKA/mTOR and inhibiting autophagy via DP2-PI3K/AKT/mTOR.
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Affiliation(s)
- Yang Yang
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China.,Department of Pharmacology, Chongqing Health Center for Women and Children Chongqing 400016, China
| | - Pu Xiang
- Department of pharmacy,Dianjiang People's Hospital of Chongqing, Dianjiang, Chongqing 408300, China
| | - Qi Chen
- Pharmacy department of GuiZhou Provincial People,s Hospital, Guiyang 550000, China
| | - Ying Luo
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Hong Wang
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Huan Li
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Lu Yang
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Congli Hu
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Jiahua Zhang
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Yuke Li
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Hui Xia
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Zhihao Chen
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
| | - Junqing Yang
- Department of Pharmacology, Chongqing Medical University, the Key Laboratory of Biochemistry and Molecular Pharmacology, Chongqing 400016, China
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11
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Glucagon transiently stimulates mTORC1 by activation of an EPAC/Rap1 signaling axis. Cell Signal 2021; 84:110010. [PMID: 33872697 PMCID: PMC8169602 DOI: 10.1016/j.cellsig.2021.110010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 11/22/2022]
Abstract
Activation of the protein kinase mechanistic target of rapamycin (mTOR) in both complexes 1 and 2 (mTORC1/2) in the liver is repressed during fasting and rapidly stimulated in response to a meal. The effect of feeding on hepatic mTORC1/2 is attributed to an increase in plasma levels of nutrients, such as amino acids, and insulin. By contrast, fasting is associated with elevated plasma levels of glucagon, which is conventionally viewed as having a counter-regulatory role to insulin. More recently an expanded role for glucagon action in post-prandial metabolism has been demonstrated. Herein we investigated the impact of insulin and glucagon on mTORC1/2 activation. In H4IIE and HepG2 cultures, insulin enhanced phosphorylation of the mTORC1 substrates S6K1 and 4E-BP1. Surprisingly, the effect of glucagon on mTORC1 was biphasic, wherein there was an acute increase in phosphorylation of S6K1 and 4E-BP1 over the first hour of exposure, followed by latent suppression. The transient stimulatory effect of glucagon on mTORC1 was not additive with insulin, suggesting convergent signaling. Glucagon enhanced cAMP levels and mTORC1 stimulation required activation of the glucagon receptor, PI3K/Akt, and exchange protein activated by cAMP (EPAC). EPAC acts as the guanine nucleotide exchange factor for the small GTPase Rap1. Rap1 expression enhanced S6K1 phosphorylation and glucagon addition to culture medium promoted Rap1-GTP loading. Signaling through mTORC1 acts to regulate protein synthesis and we found that glucagon promoted an EPAC-dependent increase in protein synthesis. Overall, the findings support that glucagon elicits acute activation of mTORC1/2 by an EPAC-dependent increase in Rap1-GTP.
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Wehbe N, Slika H, Mesmar J, Nasser SA, Pintus G, Baydoun S, Badran A, Kobeissy F, Eid AH, Baydoun E. The Role of Epac in Cancer Progression. Int J Mol Sci 2020; 21:ijms21186489. [PMID: 32899451 PMCID: PMC7555121 DOI: 10.3390/ijms21186489] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/28/2020] [Accepted: 07/29/2020] [Indexed: 12/14/2022] Open
Abstract
Cancer continues to be a prime contributor to global mortality. Despite tremendous research efforts and major advances in cancer therapy, much remains to be learned about the underlying molecular mechanisms of this debilitating disease. A better understanding of the key signaling events driving the malignant phenotype of cancer cells may help identify new pharmaco-targets. Cyclic adenosine 3',5'-monophosphate (cAMP) modulates a plethora of biological processes, including those that are characteristic of malignant cells. Over the years, most cAMP-mediated actions were attributed to the activity of its effector protein kinase A (PKA). However, studies have revealed an important role for the exchange protein activated by cAMP (Epac) as another effector mediating the actions of cAMP. In cancer, Epac appears to have a dual role in regulating cellular processes that are essential for carcinogenesis. In addition, the development of Epac modulators offered new routes to further explore the role of this cAMP effector and its downstream pathways in cancer. In this review, the potentials of Epac as an attractive target in the fight against cancer are depicted. Additionally, the role of Epac in cancer progression, namely its effect on cancer cell proliferation, migration/metastasis, and apoptosis, with the possible interaction of reactive oxygen species (ROS) in these phenomena, is discussed with emphasis on the underlying mechanisms and pathways.
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Affiliation(s)
- Nadine Wehbe
- Department of Biology, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon; (N.W.); (J.M.)
| | - Hasan Slika
- Department of Pharmacology and Therapeutics, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon;
| | - Joelle Mesmar
- Department of Biology, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon; (N.W.); (J.M.)
| | - Suzanne A. Nasser
- Department of Pharmacology, Beirut Arab University, P.O. Box 11-5020 Beirut, Lebanon;
| | - Gianfranco Pintus
- Department of Biomedical Sciences, University of Sharjah, P.O. Box 27272 Sharjah, UAE;
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43, 07100 Sassari, Italy
| | - Serine Baydoun
- Department of Radiology, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon;
| | - Adnan Badran
- Department of Basic Sciences, University of Petra, P.O. Box 961343, Amman 11196, Jordan;
| | - Firas Kobeissy
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Beirut, Lebanon;
| | - Ali H. Eid
- Department of Pharmacology and Therapeutics, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon;
- Department of Pharmacology and Therapeutics, Faculty of Medicine, American University of Beirut, P.O. Box 11-0236, Beirut, Lebanon
- Correspondence: (A.H.E.); (E.B.); Tel.: +961-1-350-000 (ext. 4891) (A.H.E. & E.B.)
| | - Elias Baydoun
- Department of Biology, American University of Beirut, P.O. Box 11-0236 Beirut, Lebanon; (N.W.); (J.M.)
- Correspondence: (A.H.E.); (E.B.); Tel.: +961-1-350-000 (ext. 4891) (A.H.E. & E.B.)
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EPAC in Vascular Smooth Muscle Cells. Int J Mol Sci 2020; 21:ijms21145160. [PMID: 32708284 PMCID: PMC7404248 DOI: 10.3390/ijms21145160] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/09/2020] [Accepted: 07/19/2020] [Indexed: 02/07/2023] Open
Abstract
Vascular smooth muscle cells (VSMCs) are major components of blood vessels. They regulate physiological functions, such as vascular tone and blood flow. Under pathological conditions, VSMCs undergo a remodeling process known as phenotypic switching. During this process, VSMCs lose their contractility and acquire a synthetic phenotype, where they over-proliferate and migrate from the tunica media to the tunica interna, contributing to the occlusion of blood vessels. Since their discovery as effector proteins of cyclic adenosine 3′,5′-monophosphate (cAMP), exchange proteins activated by cAMP (EPACs) have been shown to play vital roles in a plethora of pathways in different cell systems. While extensive research to identify the role of EPAC in the vasculature has been conducted, much remains to be explored to resolve the reported discordance in EPAC’s effects. In this paper, we review the role of EPAC in VSMCs, namely its regulation of the vascular tone and phenotypic switching, with the likely involvement of reactive oxygen species (ROS) in the interplay between EPAC and its targets/effectors.
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Chen Y, Li Q, Li Q, Xing S, Liu Y, Liu Y, Chen Y, Liu W, Feng F, Sun H. p62/SQSTM1, a Central but Unexploited Target: Advances in Its Physiological/Pathogenic Functions and Small Molecular Modulators. J Med Chem 2020; 63:10135-10157. [DOI: 10.1021/acs.jmedchem.9b02038] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Ying Chen
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Qi Li
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Qihang Li
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Shuaishuai Xing
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Yang Liu
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Yijun Liu
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Yao Chen
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, People’s Republic of China
| | - Wenyuan Liu
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
| | - Feng Feng
- Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
- Jiangsu Food and Pharmaceuticals Science College, Institute of Food and Pharmaceuticals Research, Huaian 223005, People’s Republic of China
| | - Haopeng Sun
- School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People’s Republic of China
- Jiangsu Food and Pharmaceuticals Science College, Institute of Food and Pharmaceuticals Research, Huaian 223005, People’s Republic of China
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Massimi M, Ragusa F, Cardarelli S, Giorgi M. Targeting Cyclic AMP Signalling in Hepatocellular Carcinoma. Cells 2019; 8:cells8121511. [PMID: 31775395 PMCID: PMC6952960 DOI: 10.3390/cells8121511] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is a major healthcare problem worldwide, representing one of the leading causes of cancer mortality. Since there are currently no predictive biomarkers for early stage diagnosis, HCC is detected only in advanced stages and most patients die within one year, as radical tumour resection is generally performed late during the disease. The development of alternative therapeutic approaches to HCC remains one of the most challenging areas of cancer. This review focuses on the relevance of cAMP signalling in the development of hepatocellular carcinoma and identifies the modulation of this second messenger as a new strategy for the control of tumour growth. In addition, because the cAMP pathway is controlled by phosphodiesterases (PDEs), targeting these enzymes using PDE inhibitors is becoming an attractive and promising tool for the control of HCC. Among them, based on current preclinical and clinical findings, PDE4-specific inhibitors remarkably demonstrate therapeutic potential in the management of cancer outcomes, especially as adjuvants to standard therapies. However, more preclinical studies are warranted to ascertain their efficacy during the different stages of hepatocyte transformation and in the treatment of established HCC.
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Affiliation(s)
- Mara Massimi
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy;
- Correspondence: (M.M.); (M.G.); Tel.: +39-0862-433219 (M.M.); +39-06-49912308 (M.G.)
| | - Federica Ragusa
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy;
| | - Silvia Cardarelli
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza University of Rome, 00185 Rome, Italy;
| | - Mauro Giorgi
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza University of Rome, 00185 Rome, Italy;
- Correspondence: (M.M.); (M.G.); Tel.: +39-0862-433219 (M.M.); +39-06-49912308 (M.G.)
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Smith SA, Newby AC, Bond M. Ending Restenosis: Inhibition of Vascular Smooth Muscle Cell Proliferation by cAMP. Cells 2019; 8:cells8111447. [PMID: 31744111 PMCID: PMC6912325 DOI: 10.3390/cells8111447] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 12/17/2022] Open
Abstract
Increased vascular smooth muscle cell (VSMC) proliferation contributes towards restenosis after angioplasty, vein graft intimal thickening and atherogenesis. The second messenger 3′ 5′ cyclic adenosine monophosphate (cAMP) plays an important role in maintaining VSMC quiescence in healthy vessels and repressing VSMC proliferation during resolution of vascular injury. Although the anti-mitogenic properties of cAMP in VSMC have been recognised for many years, it is only recently that we gained a detailed understanding of the underlying signalling mechanisms. Stimuli that elevate cAMP in VSMC inhibit G1-S phase cell cycle progression by inhibiting expression of cyclins and preventing S-Phase Kinase Associated Protein-2 (Skp2-mediated degradation of cyclin-dependent kinase inhibitors. Early studies implicated inhibition of MAPK signalling, although this does not fully explain the anti-mitogenic effects of cAMP. The cAMP effectors, Protein Kinase A (PKA) and Exchange Protein Activated by cAMP (EPAC) act together to inhibit VSMC proliferation by inducing Cyclic-AMP Response Element Binding protein (CREB) activity and inhibiting members of the RhoGTPases, which results in remodelling of the actin cytoskeleton. Cyclic-AMP induced actin remodelling controls proliferation by modulating the activity of Serum Response Factor (SRF) and TEA Domain Transcription Factors (TEAD), which regulate expression of genes required for proliferation. Here we review recent research characterising these mechanisms, highlighting novel drug targets that may allow the anti-mitogenic properties of cAMP to be harnessed therapeutically to limit restenosis.
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Affiliation(s)
| | | | - Mark Bond
- Correspondence: ; Tel.: +44-117-3423586
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Zhang X, Cao S, Barila G, Edreira MM, Hong K, Wankhede M, Naim N, Buck M, Altschuler DL. Cyclase-associated protein 1 (CAP1) is a prenyl-binding partner of Rap1 GTPase. J Biol Chem 2018; 293:7659-7673. [PMID: 29618512 PMCID: PMC5961064 DOI: 10.1074/jbc.ra118.001779] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 02/22/2018] [Indexed: 12/20/2022] Open
Abstract
Rap1 proteins are members of the Ras subfamily of small GTPases involved in many biological responses, including adhesion, cell proliferation, and differentiation. Like all small GTPases, they work as molecular allosteric units that are active in signaling only when associated with the proper membrane compartment. Prenylation, occurring in the cytosol, is an enzymatic posttranslational event that anchors small GTPases at the membrane, and prenyl-binding proteins are needed to mask the cytoplasm-exposed lipid during transit to the target membrane. However, several of these proteins still await discovery. In this study, we report that cyclase-associated protein 1 (CAP1) binds Rap1. We found that this binding is GTP-independent, does not involve Rap1's effector domain, and is fully contained in its C-terminal hypervariable region (HVR). Furthermore, Rap1 prenylation was required for high-affinity interactions with CAP1 in a geranylgeranyl-specific manner. The prenyl binding specifically involved CAP1's C-terminal hydrophobic β-sheet domain. We present a combination of experimental and computational approaches, yielding a model whereby the high-affinity binding between Rap1 and CAP1 involves electrostatic and nonpolar side-chain interactions between Rap1's HVR residues, lipid, and CAP1 β-sheet domain. The binding was stabilized by the lipid insertion into the β-solenoid whose interior was occupied by nonpolar side chains. This model was reminiscent of the recently solved structure of the PDEδ-K-Ras complex; accordingly, disruptors of this complex, e.g. deltarasin, blocked the Rap1-CAP1 interaction. These findings indicate that CAP1 is a geranylgeranyl-binding partner of Rap1.
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Affiliation(s)
- Xuefeng Zhang
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Shufen Cao
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44116
| | - Guillermo Barila
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Martin M Edreira
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Kyoungja Hong
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Mamta Wankhede
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Nyla Naim
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Matthias Buck
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44116
| | - Daniel L Altschuler
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
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18
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Robichaux WG, Cheng X. Intracellular cAMP Sensor EPAC: Physiology, Pathophysiology, and Therapeutics Development. Physiol Rev 2018; 98:919-1053. [PMID: 29537337 PMCID: PMC6050347 DOI: 10.1152/physrev.00025.2017] [Citation(s) in RCA: 138] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/13/2022] Open
Abstract
This review focuses on one family of the known cAMP receptors, the exchange proteins directly activated by cAMP (EPACs), also known as the cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFs). Although EPAC proteins are fairly new additions to the growing list of cAMP effectors, and relatively "young" in the cAMP discovery timeline, the significance of an EPAC presence in different cell systems is extraordinary. The study of EPACs has considerably expanded the diversity and adaptive nature of cAMP signaling associated with numerous physiological and pathophysiological responses. This review comprehensively covers EPAC protein functions at the molecular, cellular, physiological, and pathophysiological levels; and in turn, the applications of employing EPAC-based biosensors as detection tools for dissecting cAMP signaling and the implications for targeting EPAC proteins for therapeutic development are also discussed.
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Affiliation(s)
- William G Robichaux
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
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19
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Insights into exchange factor directly activated by cAMP (EPAC) as potential target for cancer treatment. Mol Cell Biochem 2018; 447:77-92. [PMID: 29417338 DOI: 10.1007/s11010-018-3294-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Accepted: 01/19/2018] [Indexed: 01/02/2023]
Abstract
Cancer remains a global health problem and approximately 1.7 million new cancer cases are diagnosed every year worldwide. Although diverse molecules are currently being explored as targets for cancer therapy the tumor treatment and therapy is highly tricky. Secondary messengers are important for hormone-mediated signaling pathway. Cyclic AMP (cAMP), a secondary messenger responsible for various physiological processes regulates cell metabolism by activating Protein kinase A (PKA) and by targeting exchange protein directly activated by cAMP (EPAC). EPAC is present in two isoforms EPAC1 and EPAC2, which exhibit different tissue distribution and is involved in GDP/GTP exchange along with activating Rap1- and Rap2-mediated signaling pathways. EPAC is also known for its dual role in cancer as pro- and anti-proliferative in addition to metastasis. Results after perturbing EPAC activity suggests its involvement in cancer cell migration, proliferation, and cytoskeleton remodeling which makes it a potential therapeutic target for cancer treatments.
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Overexpression of exchange protein directly activated by cAMP-1 (EPAC1) attenuates bladder cancer cell migration. Biochem Biophys Res Commun 2017; 495:64-70. [PMID: 29111327 DOI: 10.1016/j.bbrc.2017.10.142] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 10/26/2017] [Indexed: 12/11/2022]
Abstract
Exchange protein directly activated by cAMP (EPAC) is a mediator of a cAMP signaling pathway that is independent of protein kinase A. EPAC has two isoforms (EPAC1 and EPAC2) and is a cAMP-dependent guanine nucleotide exchange factor for the small GTPases, Rap1 and Rap2. Recent studies suggest that EPAC1 has both positive and negative influences on cancer and is involved in cell proliferation, apoptosis, migration and metastasis. We report that EPAC1 and EPAC2 expression levels were significantly lower in bladder cancer tissue than in normal bladder tissue. In addition, bladder cancer cell lines showed reduced EPAC1 mRNA expression. Furthermore, EPAC1 overexpression in bladder cancer cell lines induced morphologic changes and markedly suppressed cell migration without affecting cell viability. The overexpressed EPAC1 preferentially localized at cell-cell interfaces. In conclusion, reduced EPAC1 expression in bladder tumors and poor migration of EPAC1-overexpressing cells implicate EPAC1 as an inhibitor of bladder cancer cell migration.
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Guan Z, Zhuang W, Lei H, Wang D, Yao Y, Guo D, Sun Q, Chen Y, Chen X, Lin H, Teng B, Zhang Y. Epac1, PDE4, and PKC protein expression and their correlation with AKAP95 and Cx43 in esophagus cancer tissues. Thorac Cancer 2017; 8:572-576. [PMID: 28771997 PMCID: PMC5668522 DOI: 10.1111/1759-7714.12479] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/13/2017] [Accepted: 06/13/2017] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND This study examined the expression of exchange protein directly activated by cAMP1 (Epac1), PDE4, and PKC in esophageal cancer tissues, and analyzed the association of each protein with the pathological parameters of the samples. METHODS Epac1, PDE4, and PKC protein expression was evaluated by PV-9000 two-step immunohistochemical techniques in 51 esophageal cancer specimens and 10 para-carcinoma tissues. RESULTS The positive expression rates of Epac1 and PKC in esophageal cancer tissues (62.7% and 68.6%, respectively) were higher compared to those in para-carcinoma tissues (20% and 20%, respectively) (P < 0.05). The positive expression rate of PDE4 in esophageal cancer tissues (54.1%) was higher than in para-carcinoma tissues (30%), (P > 0.05). Epac1, PDE4, and PKC protein expression levels were not associated with the extent of tumor differentiation and/or lymph node metastasis (P > 0.05). Epac1 protein expression levels correlated with PDE4, PKC, and AKAP95 protein expression levels. In addition, there was a correlation between PKC and Cx43 protein levels (P < 0.05). CONCLUSION The expression rates of Epac1, PDE4, and PKC protein in esophageal cancer tissues were significantly higher compared to the rates in para-carcinoma tissues, suggesting an association between these proteins and the development and progression of esophageal cancer. The correlations between these proteins also revealed that they may exert a synergistic effect during the development of esophageal cancer.
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Affiliation(s)
- Zhiyu Guan
- Department of Thoracic Surgery, The Second Hospital of Tianjin Medical University, Tianjin, China
| | - Winxin Zhuang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Hui Lei
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Dai Wang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Youliang Yao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Dongbei Guo
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Qian Sun
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Yun Chen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Xiaoyi Chen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Hongyan Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Bogang Teng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Yongxing Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
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Huang P, Sun Q, Zhuang W, Peng K, Wang D, Yao Y, Guo D, Zhang L, Shen C, Sun M, Tang C, Teng B, Zhang Y. Epac1, PDE4, and PKC protein expression and their association with AKAP95, Cx43, and cyclinD2/E1 in breast cancer tissues. Thorac Cancer 2017; 8:495-500. [PMID: 28755423 PMCID: PMC5582487 DOI: 10.1111/1759-7714.12475] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/11/2017] [Accepted: 06/11/2017] [Indexed: 12/03/2022] Open
Abstract
Background This study was conducted to investigate the exchange protein directly activated by cAMP (Epac1), PDE4, and PKC expression in breast cancer tissues, and the correlation between these proteins and AKAP95, Cx43, cyclin D2, and cyclin E1. Methods PV‐9000 two‐step immunohistochemistry was used to analyze protein expression. Results The positive rate of Epac1 protein expression in breast cancer tissues (58%) was higher than in para‐carcinoma tissues (10%) (P < 0.05). There were no significant differences in the positive rates of PDE4 and PKC expression between breast cancer and para‐carcinoma tissues (P > 0.05). The positive expression rate of PDE4 was higher in the P53 protein positive group compared to the P53 negative group (P < 0.05). Correlations between Epac1 and cyclin D2, PDE4 and cyclin D2, AKAP95 and PKC, Cx43 and PKC, and cyclin D2 and PKC proteins were observed (P < 0.05). Conclusion Epac1 expression in breast cancer tissues was increased, suggesting that the protein may be involved in the development of breast cancer. Correlations between Epac1 and cyclin D2, PDE4 and cyclin D2, AKAP95 and PKC, Cx43 and PKC, and cyclin D2 and PKC proteins suggested synergistic effects among these proteins in the development of breast cancer.
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Affiliation(s)
- Ping Huang
- Department of Gynecology, Qilu Hospital of Shandong University, Jinan, China
| | - Qian Sun
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Wenxin Zhuang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Kuan Peng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Dai Wang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Youliang Yao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Dongbei Guo
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Lu Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Chuhan Shen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Mengyun Sun
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Chaoying Tang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Bogang Teng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Yongxing Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
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Sun DP, Fang CL, Chen HK, Wen KS, Hseu YC, Hung ST, Uen YH, Lin KY. EPAC1 overexpression is a prognostic marker and its inhibition shows promising therapeutic potential for gastric cancer. Oncol Rep 2017; 37:1953-1960. [PMID: 28260059 PMCID: PMC5367365 DOI: 10.3892/or.2017.5442] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 02/01/2017] [Indexed: 01/18/2023] Open
Abstract
cAMP signaling controls a variety of cellular functions. In addition to the well-known signal transducer cAMP-dependent protein kinase, a more recently discovered transducer is the exchange protein directly activated by cAMP (EPAC). EPAC responses are mediated by small G proteins, which regulate biologic functions such as cell adhesion, migration and proliferation. Recently, the clinical importance of EPAC1 has received increased attention. This study investigated the correlations between the expression of EPAC1 and various clinicopathologic parameters as well as the survival of the patients with gastric cancer (GC). The patient cohort in this study consisted of 141 cases of GC that presented from 1999 through 2011; documented clinicopathologic parameters and clinical outcomes were available for all cases. Immunoblotting, immunohistochemistry and quantitative real-time PCR were used to examine EPAC1 expression in gastric cells and tissues. siRNA technology was used to study the effect of EPAC1 knockdown on cell proliferation and invasion. An increase in EPAC1 expression was found in GC cells and tissues. The overexpression of EPAC1 was associated with the depth of invasion (P=0.0021), stage (P=0.0429), and vascular invasion (P=0.0049) and was correlated with poor disease-free survival (P=0.0029) and overall survival (P=0.0024). A univariate Cox regression analysis showed that the overexpression of EPAC1 was a prognostic marker for GC (P=0.038). Furthermore, cell studies indicated that the knockdown of EPAC1 in GC cells suppressed cell proliferation and invasion. The overexpression of EPAC1 can be used as a marker to predict the outcome of patients with GC, and EPAC1 represents a potential therapeutic modality for treating GC.
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Affiliation(s)
- Ding-Ping Sun
- Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan, R.O.C
| | - Chia-Lang Fang
- Department of Pathology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, R.O.C
| | - Han-Kun Chen
- Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan, R.O.C
| | - Kuo-Shan Wen
- Department of Pharmacy, Chi Mei Medical Center, Tainan, Taiwan, R.O.C
| | - You-Cheng Hseu
- Department of Cosmeceutics, China Medical University, Taichung, Taiwan, R.O.C
| | - Shih-Ting Hung
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan, R.O.C
| | - Yih-Huei Uen
- The Superintendent's Office, Chi Mei Hospital Chiali, Tainan, Taiwan, R.O.C
| | - Kai-Yuan Lin
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan, R.O.C
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Mandal A, Agrahari V, Khurana V, Pal D, Mitra AK. Transporter effects on cell permeability in drug delivery. Expert Opin Drug Deliv 2016; 14:385-401. [PMID: 27449574 DOI: 10.1080/17425247.2016.1214565] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
INTRODUCTION The role of drug transporters as one of the determinants of cellular drug permeability has become increasingly evident. Despite the lipophilicity of a drug molecule as rate-limiting factor for passive diffusion across biological membranes, carrier-mediated and active transport have gained attention over the years. A better understanding of the effects and roles of these influx transporters towards transmembrane permeability of a drug molecule need to be delineated for drug development and delivery. Areas covered: This review focuses on findings relative to role of transporters in drug absorption and bioavailability. Particularly the areas demanding further research have been emphasized. This review will also highlight various transporters expressed on vital organs and their effects on drug pharmacokinetics. Expert opinion: Significant efforts have been devoted to understand the role of transporters, their iterative interplay with metabolizing enzymes through molecular enzymology, binding and structure-activity relationship studies. A few assays such as parallel artificial membrane permeation assay (PAMPA) have been developed to analyze drug transport across phospholipid membranes. Although large web-accessible databases on tissue selective expression profiles at transcriptomic as well as proteomic are available, there is a need to collocate the scattered literature on the role of transporters in drug development and delivery.
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Affiliation(s)
- Abhirup Mandal
- a Division of Pharmaceutical Sciences, School of Pharmacy , University of Missouri-Kansas City , Kansas City , MO , USA
| | - Vibhuti Agrahari
- a Division of Pharmaceutical Sciences, School of Pharmacy , University of Missouri-Kansas City , Kansas City , MO , USA
| | - Varun Khurana
- b R&D , INSYS Therapeutics Inc , Chandler , AZ , USA
| | - Dhananjay Pal
- a Division of Pharmaceutical Sciences, School of Pharmacy , University of Missouri-Kansas City , Kansas City , MO , USA
| | - Ashim K Mitra
- c UMKC School of Pharmacy, Division of Pharmaceutical Sciences , University of Missouri-Kansas City , Kansas City , MO , USA
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25
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Amunjela JN, Tucker SJ. POPDC proteins as potential novel therapeutic targets in cancer. Drug Discov Today 2016; 21:1920-1927. [PMID: 27458118 DOI: 10.1016/j.drudis.2016.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 07/10/2016] [Accepted: 07/18/2016] [Indexed: 02/08/2023]
Abstract
Popeye domain-containing (POPDC) proteins are a novel class of cAMP-binding molecules that affect cancer cell behaviour and correlate with poor clinical outcomes. They are encoded by the POPDC genes POPDC1, POPDC2, and POPDC3. The deletion of POPDC genes and the suppression of POPDC proteins correlate with enhanced cancer cell proliferation, migration, invasion, metastasis, drug resistance, and poor patient survival in various human cancers. Overexpression of POPDC proteins inhibits cancer cell migration and invasion in vitro. POPDC proteins present promising anticancer therapeutic targets and here we review their roles in promoting cancer progression and highlight their potential as anticancer therapeutic targets.
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Affiliation(s)
- Johanna N Amunjela
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Steven J Tucker
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
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26
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Cao S, Bian Z, Zhu X, Shen SR. Effect of Epac1 on pERK and VEGF Activation in Postoperative Persistent Pain in Rats. J Mol Neurosci 2016; 59:554-64. [DOI: 10.1007/s12031-016-0776-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/02/2016] [Indexed: 02/01/2023]
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27
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Gao M, Ma Y, Bast RC, Li Y, Wan L, Liu Y, Sun Y, Fang Z, Zhang L, Wang X, Wei Z. Epac1 knockdown inhibits the proliferation of ovarian cancer cells by inactivating AKT/Cyclin D1/CDK4 pathway in vitro and in vivo. Med Oncol 2016; 33:73. [PMID: 27277757 DOI: 10.1007/s12032-016-0786-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 05/27/2016] [Indexed: 12/14/2022]
Abstract
Ovarian cancer is the leading cause of death among gynecological malignancies, and high grade serous ovarian carcinoma is the most common and most aggressive subtype. Recently, it was demonstrated that cAMP mediates protein kinase A-independent effects through Epac (exchange protein directly activated by cAMP) proteins. Epac proteins, including Epac1 and Epac2, are implicated in several diverse cellular responses, such as insulin secretion, exocytosis, cellular calcium handling and formation of cell-cell junctions. Several reports document that Epac1 could play vital roles in promoting proliferation, invasion and migration of some cancer cells. However, the expression levels and roles of Epac1 in ovarian cancer have not been investigated. In the present study, we detected the expression levels of Epac1 mRNA and protein in three kinds of ovarian cancer cells SKOV3, OVCAR3 and CAOV3. Furthermore, the effect of Epac1 knockdown on the proliferation and apoptosis of SKOV3 and OVCAR3 cells was evaluated in vitro and in vivo. The results showed that there was higher expression of Epac1 mRNA and protein in SKOV3 and OVCAR3 cells. Epac1 knockdown inhibited the proliferation of SKOV3 and OVCAR3 cells in vitro and in vivo. Decreased proliferation may be due to downregulation of Epac1-induced G1 phase arrest by inactivating the AKT/Cyclin D1/CDK4 pathway, but not to alterations in the MAPK pathway or to apoptosis. Taken together, our data provide new insight into the essential role of Epac1 in regulating growth of ovarian cancer cells and suggest that Epac1 might represent an attractive therapeutic target for treatment of ovarian cancer.
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Affiliation(s)
- Meng Gao
- Department of Immunology, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Yanyan Ma
- Department of Immunology, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Robert C Bast
- Department of Experimental Therapeutics, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yue Li
- Department of Immunology, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Lu Wan
- Department of Immunology, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Yanping Liu
- Department of Gynecology and Obstetrics, Jinan Central Hospital Affiliated to Shandong University, 105# Jiefang Road, Jinan, 250013, Shandong, People's Republic of China.,Department of Gynecology and Obstetrics, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Yingshuo Sun
- Department of Gynecology and Obstetrics, Jinan Central Hospital Affiliated to Shandong University, 105# Jiefang Road, Jinan, 250013, Shandong, People's Republic of China.,Department of Gynecology and Obstetrics, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Zhenghui Fang
- Department of Gynecology and Obstetrics, Jinan Central Hospital Affiliated to Shandong University, 105# Jiefang Road, Jinan, 250013, Shandong, People's Republic of China
| | - Lining Zhang
- Department of Immunology, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China
| | - Xiaoyan Wang
- Department of Immunology, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China.
| | - Zengtao Wei
- Department of Gynecology and Obstetrics, Jinan Central Hospital Affiliated to Shandong University, 105# Jiefang Road, Jinan, 250013, Shandong, People's Republic of China. .,Department of Gynecology and Obstetrics, Shandong University School of Medicine, 44# Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China.
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28
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Almahariq M, Mei FC, Cheng X. The pleiotropic role of exchange protein directly activated by cAMP 1 (EPAC1) in cancer: implications for therapeutic intervention. Acta Biochim Biophys Sin (Shanghai) 2016; 48:75-81. [PMID: 26525949 DOI: 10.1093/abbs/gmv115] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 08/30/2015] [Indexed: 01/03/2023] Open
Abstract
The pleiotropic second messenger adenosine 3',5'-cyclic monophosphate (cAMP) regulates a myriad of biological processes under both physiological and pathophysiological conditions. Exchange protein directly activated by cAMP 1 (EPAC1) mediates the intracellular functions of cAMP by acting as a guanine nucleotide exchange factor for the Ras-like Rap small GTPases. Recent studies suggest that EPAC1 plays important roles in immunomodulation, cancer cell migration/metastasis, and metabolism. These results, coupled with the successful development of EPAC-specific small molecule inhibitors, identify EPAC1 as a promising therapeutic target for cancer treatments.
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Affiliation(s)
- Muayad Almahariq
- Department of Pharmacology and Toxicology, The University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Fang C Mei
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
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29
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Abstract
Nociceptors and neurons in the central nervous system (CNS) that receive nociceptive input show remarkable plasticity in response to injury. This plasticity is thought to underlie the development of chronic pain states. Hence, further understanding of the molecular mechanisms driving and maintaining this plasticity has the potential to lead to novel therapeutic approaches for the treatment of chronic pain states. An important concept in pain plasticity is the presence and persistence of "hyperalgesic priming." This priming arises from an initial injury and results in a remarkable susceptibility to normally subthreshold noxious inputs causing a prolonged pain state in primed animals. Here we describe our current understanding of how this priming is manifested through changes in signaling in the primary nociceptor as well as through memory like alterations at CNS synapses. Moreover, we discuss how commonly utilized analgesics, such as opioids, enhance priming therefore potentially contributing to the development of persistent pain states. Finally we highlight where these priming models draw parallels to common human chronic pain conditions. Collectively, these advances in our understanding of pain plasticity reveal a variety of targets for therapeutic intervention with the potential to reverse rather than palliate chronic pain states.
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Affiliation(s)
- Ram Kandasamy
- Department of Pharmacology, The University of Arizona, Tucson, AZ, 85721, USA
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30
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Misra UK, Pizzo SV. Activated α2-macroglobulin binding to human prostate cancer cells triggers insulin-like responses. J Biol Chem 2015; 290:9571-87. [PMID: 25720493 DOI: 10.1074/jbc.m114.617837] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Indexed: 12/21/2022] Open
Abstract
Ligation of cell surface GRP78 by activated α2-macroglobulin (α2M*) promotes cell proliferation and suppresses apoptosis. α2M*-treated human prostate cancer cells exhibit a 2-3-fold increase in glucose uptake and lactate secretion, an effect similar to insulin treatment. In both α2M* and insulin-treated cells, the mRNA levels of SREBP1-c, SREBP2, fatty-acid synthase, acetyl-CoA carboxylase, ATP citrate lyase, and Glut-1 were significantly increased together with their protein levels, except for SREBP2. Pretreatment of cells with α2M* antagonist antibody directed against the carboxyl-terminal domain of GRP78 blocks these α2M*-mediated effects, and silencing GRP78 expression by RNAi inhibits up-regulation of ATP citrate lyase and fatty-acid synthase. α2M* induces a 2-3-fold increase in lipogenesis as determined by 6-[(14)C]glucose or 1-[(14)C]acetate incorporation into free cholesterol, cholesterol esters, triglycerides, free fatty acids, and phosphatidylcholine, which is blocked by inhibitors of fatty-acid synthase, PI 3-kinase, mTORC, or an antibody against the carboxyl-terminal domain of GRP78. We also assessed the incorporation of [(14)CH3]choline into phosphatidylcholine and observed similar effects. Lipogenesis is significantly affected by pretreatment of prostate cancer cells with fatostatin A, which blocks sterol regulatory element-binding protein proteolytic cleavage and activation. This study demonstrates that α2M* functions as a growth factor, leading to proliferation of prostate cancer cells by promoting insulin-like responses. An antibody against the carboxyl-terminal domain of GRP78 may have important applications in prostate cancer therapy.
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Affiliation(s)
- Uma Kant Misra
- From the Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710
| | - Salvatore Vincent Pizzo
- From the Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710
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31
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Almahariq M, Chao C, Mei FC, Hellmich MR, Patrikeev I, Motamedi M, Cheng X. Pharmacological inhibition and genetic knockdown of exchange protein directly activated by cAMP 1 reduce pancreatic cancer metastasis in vivo. Mol Pharmacol 2014; 87:142-9. [PMID: 25385424 DOI: 10.1124/mol.114.095158] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
cAMP plays a critical role in regulating migration of various cancers. This role is context dependent and is determined by which of the two main cAMP sensors is at play: cAMP-dependent protein kinase or exchange protein directly activated by cAMP (EPAC). Recently, we have shown that the cAMP sensor protein EPAC1 promotes invasion/migration of pancreatic ductal adenocarcinoma (PDA) in vitro. In this study, we investigated the role of EPAC1 in invasion and metastasis of PDA in vivo, and evaluated the therapeutic potential of EPAC inhibitors as antimetastasis agents for this neoplasm. We employed an orthotopic metastatic mouse model in which the PDA cells MIA PaCa-2 were injected into the pancreas of athymic nude mice, and their local and distant spread was monitored by in vivo imaging and histologic evaluation of the number of metastatic foci in the liver. Either genetic suppression of EPAC1 or its pharmacologic inhibition with 3-(5-tert-butyl-isoxazol-3-yl)-2-[(3-chloro-phenyl)-hydrazono]-3-oxo-propionitrile, an EPAC-specific antagonist recently identified in our laboratory, decreased invasion and metastasis of the PDA cells. Mechanistically, EPAC1 promotes activation and trafficking of integrin β1, which plays an essential role in PDA migration and metastasis. Our data show that EPAC1 facilitates metastasis of PDA cells and EPAC1 might be a potential novel therapeutic target for developing antimetastasis agents for PDA.
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Affiliation(s)
- Muayad Almahariq
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
| | - Celia Chao
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
| | - Fang C Mei
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
| | - Mark R Hellmich
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
| | - Igor Patrikeev
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
| | - Massoud Motamedi
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas (M.A., F.C.M., X.C.); and Departments of Pharmacology and Toxicology (M.A.), Surgery (M.R.H., C.C.), and Ophthalmology and Visual Sciences (I.P., M.M.), University of Texas Medical Branch, Galveston, Texas
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32
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Appukuttan A, Flacke JP, Flacke H, Posadowsky A, Reusch HP, Ladilov Y. Inhibition of soluble adenylyl cyclase increases the radiosensitivity of prostate cancer cells. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2656-63. [PMID: 25257405 DOI: 10.1016/j.bbadis.2014.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 09/15/2014] [Accepted: 09/16/2014] [Indexed: 11/16/2022]
Abstract
Pharmacological modulation of tumor radiosensitivity is a promising strategy for enhancing the outcome of radiotherapy. cAMP signaling plays an essential role in modulating the proliferation and apoptosis of different cell types, including cancer cells. Until now, the regulation of this pathway was restricted to the transmembrane class of adenylyl cyclases. In the present study, the role of an alternative source of cAMP, the intracellular localized soluble adenylyl cyclase (sAC), in the radiosensitivity of prostate cancer cells was investigated. Pharmacological inhibition of sAC activity led to marked suppression of proliferation, lactate dehydrogenase release, and induction of apoptosis. The combination of ionizing radiation with partial suppression of sAC activity (~50%) immediately after irradiation synergistically inhibited proliferation and induced apoptosis. Overexpression of sAC in normal prostate epithelial PNT2 cells increased the cAMP content and accelerated cell proliferation under control conditions. The effects of radiation were significantly reduced in transformed PNT2 cells compared with control cells. Analysis of the underlying cellular mechanisms of sAC-induced radioresistance revealed the sAC-dependent activation of B-Raf/ERK1/2 signaling. In agreement with this finding, inhibition of ERK1/2 in prostate cancer cells enhanced the cytotoxic effect of irradiation. In conclusion, the present study suggests that sAC-dependent signaling plays an important role in the radioresistance of prostate cancer cells. This article is part of a Special Issue entitled: The role of soluble adenylyl cyclase in health and disease.
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Affiliation(s)
| | - Jan-Paul Flacke
- Department of Clinical Pharmacology, Ruhr-University Bochum, Germany
| | - Hanna Flacke
- Department of Clinical Pharmacology, Ruhr-University Bochum, Germany
| | | | - H Peter Reusch
- Department of Clinical Pharmacology, Ruhr-University Bochum, Germany
| | - Yury Ladilov
- Department of Clinical Pharmacology, Ruhr-University Bochum, Germany; Center for Cardiovascular Research, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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33
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Role of soluble adenylyl cyclase in cell death and growth. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2646-55. [PMID: 25010002 DOI: 10.1016/j.bbadis.2014.06.034] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 06/26/2014] [Accepted: 06/27/2014] [Indexed: 12/13/2022]
Abstract
cAMP signaling is an evolutionarily conserved intracellular communication system controlling numerous cellular functions. Until recently, transmembrane adenylyl cyclase (tmAC) was considered the major source for cAMP in the cell, and the role of cAMP signaling was therefore attributed exclusively to the activity of this family of enzymes. However, increasing evidence demonstrates the role of an alternative, intracellular source of cAMP produced by type 10 soluble adenylyl cyclase (sAC). In contrast to tmAC, sAC produces cAMP in various intracellular microdomains close to specific cAMP targets, e.g., in nucleus and mitochondria. Ongoing research demonstrates involvement of sAC in diverse physiological and pathological processes. The present review is focused on the role of cAMP signaling, particularly that of sAC, in cell death and growth. Although the contributions of sAC to the regulation of these cellular functions have only recently been discovered, current data suggest that sAC plays key roles in mitochondrial bioenergetics and the mitochondrial apoptosis pathway, as well as cell proliferation and development. Furthermore, recent reports suggest the importance of sAC in several pathologies associated with apoptosis as well as in oncogenesis. This article is part of a Special Issue entitled: The role of soluble adenylyl cyclase in health and disease.
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34
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Zhao H, Wei R, Wang L, Tian Q, Tao M, Ke J, Liu Y, Hou W, Zhang L, Yang J, Hong T. Activation of glucagon-like peptide-1 receptor inhibits growth and promotes apoptosis of human pancreatic cancer cells in a cAMP-dependent manner. Am J Physiol Endocrinol Metab 2014; 306:E1431-41. [PMID: 24801389 DOI: 10.1152/ajpendo.00017.2014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) promotes pancreatic β-cell regeneration through GLP-1 receptor (GLP-1R) activation. However, whether it promotes exocrine pancreas growth and thereby increases the risk of pancreatic cancer has been a topic of debate in recent years. Clinical data and animal studies published so far have been controversial. In the present study, we report that GLP-1R activation with liraglutide inhibited growth and promoted apoptosis in human pancreatic cancer cell lines in vitro and attenuated pancreatic tumor growth in a mouse xenograft model in vivo. These effects of liraglutide were mediated through activation of cAMP production and consequent inhibition of Akt and ERK1/2 signaling pathways in a GLP-1R-dependent manner. Moreover, we examined GLP-1R expression in human pancreatic cancer tissues and found that 43.3% of tumor tissues were GLP-1R-null. In the GLP-1R-positive tumor tissues (56.7%), the level of GLP-1R was lower compared with that in tumor-adjacent normal pancreatic tissues. Furthermore, the GLP-1R-positive tumors were significantly smaller than the GLP-1R-null tumors. Our study shows for the first time that GLP-1R activation has a cytoreductive effect on human pancreatic cancer cells in vitro and in vivo, which may help address safety concerns of GLP-1-based therapies in the context of human pancreatic cancer.
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Affiliation(s)
- Hejun Zhao
- Department of Endocrinology and Metabolism and
| | - Rui Wei
- Department of Endocrinology and Metabolism and
| | - Liang Wang
- Department of Endocrinology and Metabolism and
| | - Qing Tian
- Department of Endocrinology and Metabolism and
| | - Ming Tao
- Department of General Surgery, Peking University Third Hospital, Beijing, China
| | - Jing Ke
- Department of Endocrinology and Metabolism and
| | - Ye Liu
- Department of Endocrinology and Metabolism and
| | - Wenfang Hou
- Department of Endocrinology and Metabolism and
| | - Lin Zhang
- Department of Endocrinology and Metabolism and
| | - Jin Yang
- Department of Endocrinology and Metabolism and
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35
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Wang H, Heijnen CJ, van Velthoven CTJ, Willemen HLDM, Ishikawa Y, Zhang X, Sood AK, Vroon A, Eijkelkamp N, Kavelaars A. Balancing GRK2 and EPAC1 levels prevents and relieves chronic pain. J Clin Invest 2013; 123:5023-34. [PMID: 24231349 DOI: 10.1172/jci66241] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 09/12/2013] [Indexed: 01/12/2023] Open
Abstract
Chronic pain is a major clinical problem, yet the mechanisms underlying the transition from acute to chronic pain remain poorly understood. In mice, reduced expression of GPCR kinase 2 (GRK2) in nociceptors promotes cAMP signaling to the guanine nucleotide exchange factor EPAC1 and prolongs the PGE2-induced increase in pain sensitivity (hyperalgesia). Here we hypothesized that reduction of GRK2 or increased EPAC1 in dorsal root ganglion (DRG) neurons would promote the transition to chronic pain. We used 2 mouse models of hyperalgesic priming in which the transition from acute to chronic PGE2-induced hyperalgesia occurs. Hyperalgesic priming with carrageenan induced a sustained decrease in nociceptor GRK2, whereas priming with the PKCε agonist ΨεRACK increased DRG EPAC1. When either GRK2 was increased in vivo by viral-based gene transfer or EPAC1 was decreased in vivo, as was the case for mice heterozygous for Epac1 or mice treated with Epac1 antisense oligodeoxynucleotides, chronic PGE2-induced hyperalgesia development was prevented in the 2 priming models. Using the CFA model of chronic inflammatory pain, we found that increasing GRK2 or decreasing EPAC1 inhibited chronic hyperalgesia. Our data suggest that therapies targeted at balancing nociceptor GRK2 and EPAC1 levels have promise for the prevention and treatment of chronic pain.
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Okunishi K, DeGraaf AJ, Zasłona Z, Peters-Golden M. Inhibition of protein translation as a novel mechanism for prostaglandin E2 regulation of cell functions. FASEB J 2013; 28:56-66. [PMID: 24072780 DOI: 10.1096/fj.13-231720] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Prostaglandin E2 (PGE2) regulates numerous biological processes by modulating transcriptional activation, epigenetic control, proteolysis, and secretion of various proteins. Scar formation depends on fibroblast elaboration of matrix proteins such as collagen, and this process is strongly suppressed by PGE2 through activation of cAMP-dependent protein kinase A (PKA). However, the actual mechanism by which PGE2-PKA signaling inhibits collagen expression in fibroblasts has never been delineated, and that was the objective of this study. PGE2 unexpectedly induced a rapid reduction in procollagen I protein expression in adult lung fibroblasts, with a half-maximum effect at 1.5 h. This effect reflected its inhibition of translation rather than transcription. Global protein synthesis was also inhibited by PGE2. This action was mediated by PKA and involved both activation of ribosomal protein (rpS6) and suppression of mammalian target of rapamycin (mTOR). Similar effects of PGE2 were demonstrated in mouse peritoneal macrophages (PMs). These findings identify inhibition of translation as a new mechanism by which PGE2 regulates cellular function and a novel example of translational inhibition mediated by opposing actions on two distinct translational control pathways. Translational inhibition would be expected to contribute to dynamic alterations in cell function that accompany the changing PGE2 levels observed in disease states and with various pharmacotherapies.
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Li Y, Takahashi M, Stork PJS. Ras-mutant cancer cells display B-Raf binding to Ras that activates extracellular signal-regulated kinase and is inhibited by protein kinase A phosphorylation. J Biol Chem 2013; 288:27646-27657. [PMID: 23893412 DOI: 10.1074/jbc.m113.463067] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The small G protein Ras regulates proliferation through activation of the mitogen-activated protein (MAP) kinase (ERK) cascade. The first step of Ras-dependent activation of ERK signaling is Ras binding to members of the Raf family of MAP kinase kinase kinases, C-Raf and B-Raf. Recently, it has been reported that in melanoma cells harboring oncogenic Ras mutations, B-Raf does not bind to Ras and does not contribute to basal ERK activation. For other types of Ras-mutant tumors, the relative contributions of C-Raf and B-Raf are not known. We examined non-melanoma cancer cell lines containing oncogenic Ras mutations and express both C-Raf and B-Raf isoforms, including the lung cancer cell line H1299 cells. Both B-Raf and C-Raf were constitutively bound to oncogenic Ras and contributed to Ras-dependent ERK activation. Ras binding to B-Raf and C-Raf were both subject to inhibition by the cAMP-dependent protein kinase PKA. cAMP inhibited the growth of H1299 cells and Ras-dependent ERK activation via PKA. PKA inhibited the binding of Ras to both C-Raf and B-Raf through phosphorylations of C-Raf at Ser-259 and B-Raf at Ser-365, respectively. These studies demonstrate that in non-melanocytic Ras-mutant cancer cells, Ras signaling to B-Raf is a significant contributor to ERK activation and that the B-Raf pathway, like that of C-Raf, is a target for inhibition by PKA. We suggest that cAMP and hormones coupled to cAMP may prove useful in dampening the effects of oncogenic Ras in non-melanocytic cancer cells through PKA-dependent actions on B-Raf as well as C-Raf.
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Affiliation(s)
- Yanping Li
- Vollum Institute, Oregon Health and Science University, Portland, Oregon 97239
| | - Maho Takahashi
- Vollum Institute, Oregon Health and Science University, Portland, Oregon 97239
| | - Philip J S Stork
- Vollum Institute, Oregon Health and Science University, Portland, Oregon 97239.
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Hennenberg M, Strittmatter F, Schmetkamp H, Rutz B, Walther S, Stief CG, Gratzke C. The cAMP effector EPAC activates Elk1 transcription factor in prostate smooth muscle, and is a minor regulator of α1-adrenergic contraction. J Biomed Sci 2013; 20:46. [PMID: 23815815 PMCID: PMC3712007 DOI: 10.1186/1423-0127-20-46] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 06/19/2013] [Indexed: 11/22/2022] Open
Abstract
Background Prostate smooth muscle tone is regulated by α1-adrenoceptor-induced contraction and cAMP-mediated relaxation. EPAC is an effector of cAMP, being involved in smooth muscle relaxation and cell cycle control outside the lower urinary tract. Here, we investigated the expression and function of EPAC in human prostate tissues from patients undergoing radical prostatectomy. Results mRNA and protein expression of EPAC was detected in all prostate tissues by RT-PCR and Western blot analysis. Immunoreactivity was observed in stromal cells, and colocalized with immunofluorescence for α-smooth muscle actin and calponin. Under normal conditions, noradrenaline- or phenylephrine-induced contraction of prostate strips in the organ bath was not affected by the EPAC activator pCPT (SP-8-pCPT-2′-O-Me-cAMPS.NA) (30 μM). However, when the cyclooxygenase inhibitor indomethacin (50 μM) was added, EPAC activators pCPT and OME (8-CPT-2′-O-Me-cAMP.Na) (30 μM) significantly reduced contractions by low concentrations of phenylephrine. These effects were not observed on noradrenaline-induced contraction. OME and pCPT caused phosphorylation of the transcription factor Elk1 in prostate tissues. Elk1 activation was confirmed by EMSA (electrophoretic mobility shift assay), where OME and pCPT incresed Elk1 binding to a specific DNA probe. Conclusions EPAC activation may reduce α1-adrenergic prostate contraction in the human prostate, although this effect is masked by cyclooxygenases and β-adrenoceptors. A main EPAC function in the human prostate may be the regulation of the transcription factor Elk1.
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Affiliation(s)
- Martin Hennenberg
- Department of Urology, Ludwig-Maximilians University, Munich, Germany
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Misra UK, Payne S, Pizzo SV. The Monomeric Receptor Binding Domain of Tetrameric α2-Macroglobulin Binds to Cell Surface GRP78 Triggering Equivalent Activation of Signaling Cascades. Biochemistry 2013; 52:4014-25. [DOI: 10.1021/bi400376s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Uma Kant Misra
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, United
States
| | - Sturgis Payne
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, United
States
| | - Salvatore Vincent Pizzo
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, United
States
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Evidence for a pro-proliferative feedback loop in prostate cancer: the role of Epac1 and COX-2-dependent pathways. PLoS One 2013; 8:e63150. [PMID: 23646189 PMCID: PMC3640024 DOI: 10.1371/journal.pone.0063150] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 03/29/2013] [Indexed: 12/15/2022] Open
Abstract
Objective In human prostate cancer cells, a selective Epac agonist, 8-CPT-2Me-cAMP, upregulates cell proliferation and survival via activation of Ras-MAPK and PI- 3-kinase-Akt-mTOR signaling cascades. Here we examine the role of inflammatory mediators in Epac1-induced cellular proliferation by determining the expression of the pro-inflammatory markers p-cPLA2, COX-2, and PGE2 in prostate cancer cells treated with 8-CPT-2Me-cAMP. Methods We employed inhibitors of COX-2, mTORC1, and mTORC2 to probe cyclic AMP-dependent pathways in human prostate cancer cells. RNAi targeting Epac1, Raptor, and Rictor was also employed in these studies. Results 8-CPT-2Me-cAMP treatment caused a 2–2.5-fold increase of p-cPLA2S505, COX-2, and PGE2 levels in human prostate cancer cell lines. Pretreatment of cells with the COX-2 inhibitor SC-58125 or the EP4 antagonist AH-23848, or with an inhibitor of mTORC1 and mTORC2, Torin1, significantly reduced the Epac1-dependent increase of p-cPLA2 and COX-2, p-S6-kinaseT389, and p-AKTS473. In addition, Epac1-induced protein and DNA synthesis were greatly reduced upon pretreatment of cells with either COX-2, EP4, or mTOR inhibitors. Transfection of prostate cancer cells with Epac1 dsRNA, Raptor dsRNA, or Rictor dsRNA profoundly reduced Epac1-dependent increases in p-cPLA2 and COX-2. Conclusion We show that Epac1, a downstream effector of cAMP, functions as a pro-inflammatory modulator in prostate cancer cells and promotes cell proliferation and survival by upregulating Ras-MAPK, and PI 3-kinase-Akt-mTOR signaling.
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Flacke JP, Flacke H, Appukuttan A, Palisaar RJ, Noldus J, Robinson BD, Reusch HP, Zippin JH, Ladilov Y. Type 10 soluble adenylyl cyclase is overexpressed in prostate carcinoma and controls proliferation of prostate cancer cells. J Biol Chem 2012; 288:3126-35. [PMID: 23255611 DOI: 10.1074/jbc.m112.403279] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
cAMP signaling plays an essential role in modulating the proliferation of different cell types, including cancer cells. Until now, the regulation of this pathway was restricted to the transmembrane class of adenylyl cyclases. In this study, significant overexpression of soluble adenylyl cyclase (sAC), an alternative source of cAMP, was found in human prostate carcinoma, and therefore, the contribution of this cyclase was investigated in the prostate carcinoma cell lines LNCaP and PC3. Suppression of sAC activity by treatment with the sAC-specific inhibitor KH7 or by sAC-specific knockdown mediated by siRNA or shRNA transfection prevented the proliferation of prostate carcinoma cells, led to lactate dehydrogenase release, and induced apoptosis. Cell cycle analysis revealed a significant rise in the G(2) phase population 12 h after sAC inhibition, which was accompanied by the down-regulation of cyclin B(1) and CDK1. sAC-dependent regulation of proliferation involves the EPAC/Rap1/B-Raf signaling pathway. In contrast, protein kinase A does not play a role. In conclusion, this study suggests a novel sAC-dependent signaling pathway that controls the proliferation of prostate carcinoma cells.
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Affiliation(s)
- Jan-Paul Flacke
- Department of Clinical Pharmacology, Ruhr University Bochum, 44801 Bochum, Germany
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Misra UK, Pizzo SV. Receptor-recognized α₂-macroglobulin binds to cell surface-associated GRP78 and activates mTORC1 and mTORC2 signaling in prostate cancer cells. PLoS One 2012; 7:e51735. [PMID: 23272152 PMCID: PMC3522726 DOI: 10.1371/journal.pone.0051735] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 11/05/2012] [Indexed: 02/02/2023] Open
Abstract
OBJECTIVE Tetrameric α(2)-macroglobulin (α(2)M), a plasma panproteinase inhibitor, is activated upon interaction with a proteinase, and undergoes a major conformational change exposing a receptor recognition site in each of its subunits. Activated α(2)M (α(2)M*) binds to cancer cell surface GRP78 and triggers proliferative and antiapoptotic signaling. We have studied the role of α(2)M* in the regulation of mTORC1 and TORC2 signaling in the growth of human prostate cancer cells. METHODS Employing immunoprecipitation techniques and Western blotting as well as kinase assays, activation of the mTORC1 and mTORC2 complexes, as well as down stream targets were studied. RNAi was also employed to silence expression of Raptor, Rictor, or GRP78 in parallel studies. RESULTS Stimulation of cells with α(2)M* promotes phosphorylation of mTOR, TSC2, S6-Kinase, 4EBP, Akt(T308), and Akt(S473) in a concentration and time-dependent manner. Rheb, Raptor, and Rictor also increased. α(2)M* treatment of cells elevated mTORC1 kinase activity as determined by kinase assays of mTOR or Raptor immunoprecipitates. mTORC1 activity was sensitive to LY294002 and rapamycin or transfection of cells with GRP78 dsRNA. Down regulation of Raptor expression by RNAi significantly reduced α(2)M*-induced S6-Kinase phosphorylation at T389 and kinase activity in Raptor immunoprecipitates. α(2)M*-treated cells demonstrate about a twofold increase in mTORC2 kinase activity as determined by kinase assay of Akt(S473) phosphorylation and levels of p-Akt(S473) in mTOR and Rictor immunoprecipitates. mTORC2 activity was sensitive to LY294002 and transfection of cells with GRP78 dsRNA, but insensitive to rapamycin. Down regulation of Rictor expression by RNAi significantly reduces α(2)M*-induced phosphorylation of Akt(S473) phosphorylation in Rictor immunoprecipitates. CONCLUSION Binding of α(2)M* to prostate cancer cell surface GRP78 upregulates mTORC1 and mTORC2 activation and promotes protein synthesis in the prostate cancer cells.
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Affiliation(s)
- Uma K. Misra
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Salvatore V. Pizzo
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, United States of America
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Goncharova EA, Khavin IS, Goncharov DA, Krymskaya VP. Differential effects of formoterol on thrombin- and PDGF-induced proliferation of human pulmonary arterial vascular smooth muscle cells. Respir Res 2012. [PMID: 23186269 PMCID: PMC3545871 DOI: 10.1186/1465-9921-13-109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Background Increased pulmonary arterial vascular smooth muscle (PAVSM) cell proliferation is a key pathophysiological component of pulmonary vascular remodeling in pulmonary arterial hypertension (PH). The long-acting β2-adrenergic receptor (β2AR) agonist formoterol, a racemate comprised of (R,R)- and (S,S)-enantiomers, is commonly used as a vasodilator in chronic obstructive pulmonary disease (COPD). PH, a common complication of COPD, increases patients’ morbidity and reduces survival. Recent studies demonstrate that formoterol has anti-proliferative effects on airway smooth muscle cells and bronchial fibroblasts. The effects of formoterol and its enantiomers on PAVSM cell proliferation are not determined. The goals of this study were to examine effects of racemic formoterol and its enantiomers on PAVSM cell proliferation as it relates to COPD-associated PH. Methods Basal, thrombin-, PDGF- and chronic hypoxia-induced proliferation of primary human PAVSM cells was examined by DNA synthesis analysis using BrdU incorporation assay. ERK1/2, mTORC1 and mTORC2 activation were determined by phosphorylation levels of ERK1/2, ribosomal protein S6 and S473-Akt using immunoblot analysis. Results We found that (R,R) and racemic formoterol inhibited basal, thrombin- and chronic hypoxia-induced proliferation of human PAVSM cells while (S,S) formoterol had lesser inhibitory effect. The β2AR blocker propranolol abrogated the growth inhibitory effect of formoterol. (R,R), but not (S,S) formoterol attenuated basal, thrombin- and chronic hypoxia-induced ERK1/2 phosphorylation, but had little effect on Akt and S6 phosphorylation levels. Formoterol and its enantiomers did not significantly affect PDGF-induced DNA synthesis and PDGF-dependent ERK1/2, S473-Akt and S6 phosphorylation in human PAVSM cells. Conclusions Formoterol inhibits basal, thrombin-, and chronic hypoxia-, but not PDGF-induced human PAVSM cell proliferation and ERK1/2, but has little effect on mTORC1 and mTORC2 signaling. Anti-proliferative effects of formoterol depend predominantly on its (R,R) enantiomer and require the binding with β2AR. These data suggest that (R,R) formoterol may be considered as potential adjuvant therapy to inhibit PAVSM cell proliferation in COPD-associated PH.
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Affiliation(s)
- Elena A Goncharova
- Pulmonary, Allergy & Critical Care Division, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
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Sui H, Fan ZZ, Li Q. Signal transduction pathways and transcriptional mechanisms of ABCB1/Pgp-mediated multiple drug resistance in human cancer cells. J Int Med Res 2012; 40:426-35. [PMID: 22613403 DOI: 10.1177/147323001204000204] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Multiple drug resistance (MDR), defined as the ability of tumour cells to survive exposure to many chemotherapeutic agents, is a major cause of treatment failure in human cancers. The membrane transporter P-glycoprotein (Pgp, encoded by the ABCB1 [adenosine triphosphate-binding cassette, subfamily B, member 1] gene) is the main mechanism for decreased intracellular drug accumulation in human MDR cancer. ABCB1/Pgp-mediated MDR involves several signal transduction pathways and transcription factors. Activation of these signal transduction pathways influences the prognosis of MDR human cancer. Signalling pathways involved in ABCB1/Pgp-mediated MDR include the mitogen-activated protein kinase (MAPK), c-Jun NH(2)-terminal kinase (JNK), p38, cyclic adenosine monophosphate-dependent protein kinase, phosphatidylino sitol 3-kinase and protein kinase C signalling pathways. This review summarizes the biological characteristics, target points and signalling cascade mediators of these pathways. Drugs targeted against these pathways may provide new therapies for treatment of ABCB1/Pgp-mediated MDR.
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Affiliation(s)
- H Sui
- Interventional Cancer Institute of Chinese Integrative Medicine, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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Zhang X, Szeto C, Gao E, Tang M, Jin J, Fu Q, Makarewich C, Ai X, Li Y, Tang A, Wang J, Gao H, Wang F, Ge XJ, Kunapuli SP, Zhou L, Zeng C, Xiang KY, Chen X. Cardiotoxic and cardioprotective features of chronic β-adrenergic signaling. Circ Res 2012; 112:498-509. [PMID: 23104882 DOI: 10.1161/circresaha.112.273896] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE In the failing heart, persistent β-adrenergic receptor activation is thought to induce myocyte death by protein kinase A (PKA)-dependent and PKA-independent activation of calcium/calmodulin-dependent kinase II. β-adrenergic signaling pathways also are capable of activating cardioprotective mechanisms. OBJECTIVE This study used a novel PKA inhibitor peptide to inhibit PKA activity to test the hypothesis that β-adrenergic receptor signaling causes cell death through PKA-dependent pathways and cardioprotection through PKA-independent pathways. METHODS AND RESULTS In PKA inhibitor peptide transgenic mice, chronic isoproterenol failed to induce cardiac hypertrophy, fibrosis, and myocyte apoptosis, and decreased cardiac function. In cultured adult feline ventricular myocytes, PKA inhibition protected myocytes from death induced by β1-adrenergic receptor agonists by preventing cytosolic and sarcoplasmic reticulum Ca(2+) overload and calcium/calmodulin-dependent kinase II activation. PKA inhibition revealed a cardioprotective role of β-adrenergic signaling via cAMP/exchange protein directly activated by cAMP/Rap1/Rac/extracellular signal-regulated kinase pathway. Selective PKA inhibition causes protection in the heart after myocardial infarction that was superior to β-blocker therapy. CONCLUSIONS These results suggest that selective block of PKA could be a novel heart failure therapy.
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Affiliation(s)
- Xiaoying Zhang
- Cardiovascular Research Center, Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, USA
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Isoform-specific antagonists of exchange proteins directly activated by cAMP. Proc Natl Acad Sci U S A 2012; 109:18613-8. [PMID: 23091014 DOI: 10.1073/pnas.1210209109] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The major physiological effects of cAMP in mammalian cells are transduced by two ubiquitously expressed intracellular cAMP receptors, protein kinase A (PKA) and exchange protein directly activated by cAMP (EPAC), as well as cyclic nucleotide-gated ion channels in certain tissues. Although a large number of PKA inhibitors are available, there are no reported EPAC-specific antagonists, despite extensive research efforts. Here we report the identification and characterization of noncyclic nucleotide EPAC antagonists that are exclusively specific for the EPAC2 isoform. These EAPC2-specific antagonists, designated as ESI-05 and ESI-07, inhibit Rap1 activation mediated by EAPC2, but not EPAC1, with high potency in vitro. Moreover, ESI-05 and ESI-07 are capable of suppressing the cAMP-mediated activation of EPAC2, but not EPAC1 and PKA, as monitored in living cells through the use of EPAC- and PKA-based FRET reporters, or by the use of Rap1-GTP pull-down assays. Deuterium exchange mass spectroscopy analysis further reveals that EPAC2-specific inhibitors exert their isoform selectivity through a unique mechanism by binding to a previously undescribed allosteric site: the interface of the two cAMP binding domains, which is not present in the EPAC1 isoform. Isoform-specific EPAC pharmacological probes are highly desired and will be valuable tools for dissecting the biological functions of EPAC proteins and their roles in various disease states.
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Almahariq M, Tsalkova T, Mei FC, Chen H, Zhou J, Sastry SK, Schwede F, Cheng X. A novel EPAC-specific inhibitor suppresses pancreatic cancer cell migration and invasion. Mol Pharmacol 2012; 83:122-8. [PMID: 23066090 DOI: 10.1124/mol.112.080689] [Citation(s) in RCA: 172] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Exchange protein directly activated by cAMP (EPAC) and cAMP-dependent protein kinase (PKA) are two intracellular receptors that mediate the effects of the prototypic second messenger cAMP. Identifying pharmacological probes for selectively modulating EPAC activity represents a significant unmet need within the research field. Herein, we report the identification and characterization of 3-(5-tert-butyl-isoxazol-3-yl)-2-[(3-chloro-phenyl)-hydrazono]-3-oxo-propionitrile (ESI-09), a novel noncyclic nucleotide EPAC antagonist that is capable of specifically blocking intracellular EPAC-mediated Rap1 activation and Akt phosphorylation, as well as EPAC-mediated insulin secretion in pancreatic β cells. Using this novel EPAC-specific inhibitor, we have probed the functional roles of overexpression of EPAC1 in pancreatic cancer cells. Our studies show that EPAC1 plays an important role in pancreatic cancer cell migration and invasion, and thus represents a potential target for developing novel therapeutic strategies for pancreatic cancer.
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Affiliation(s)
- Muayad Almahariq
- Department of Pharmacology and Toxicology, The University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0615, USA.
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Abstract
Obesity is increasing worldwide and reaches to a large proportion of the population in developed countries. Thus, obesity-associated cancer has become a major health problem. Multiple cancer risk factors in obesity have been identified including insulin/insulin-like growth factor axis, adipokines and cytokines; and multiple intracellular signal pathways have been studied. However, the role of each signal pathway in obesity-associated cancer is controversial. In this review, the recent studies on signal pathways in obesity-associated cancer are summarized and a unified explanation is provided. Multiple risk factors could initially activate phosphoinositide 3-kinase (PI3K/Akt), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) pathways. With increased severity of obesity, mammalian target of rapamycin (mTOR), which is down-stream of both PI3K/Akt and MAPK, is highly activated. Activated mTOR in turn inhibits the PI3K/Akt pathway and further activates the STAT3 pathway. This may explain the activation of the PI3K/Akt pathway at the early stage of obesity and its inhibition at the later stage. mTOR inhibition may be used for cancer therapy, but it may be necessary to be combined with the PI3K/Akt inhibitor as decreased mTOR activity will release its feedback inhibition on the PI3K/Akt pathway, which is under the influence of multiple cancer risk factors in obesity. Thus, dual inhibitors of PI3K and mTOR may provide a novel approach.
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Affiliation(s)
- J Chen
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, Australia.
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Rap-linked cAMP signaling Epac proteins: Compartmentation, functioning and disease implications. Cell Signal 2011; 23:1257-66. [DOI: 10.1016/j.cellsig.2011.03.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 03/04/2011] [Accepted: 03/04/2011] [Indexed: 12/14/2022]
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50
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RNAi screen indicates widespread biological function for human natural antisense transcripts. PLoS One 2010; 5. [PMID: 20957177 PMCID: PMC2949395 DOI: 10.1371/journal.pone.0013177] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Accepted: 09/08/2010] [Indexed: 11/19/2022] Open
Abstract
Natural antisense transcripts represent a class of regulatory RNA molecules, which are characterized by their complementary sequence to another RNA transcript. Extensive sequencing efforts suggest that natural antisense transcripts are prevalent throughout the mammalian genome; however, their biological significance has not been well defined. We performed a loss-of-function RNA interference (RNAi) screen, which targeted 797 evolutionary conserved antisense transcripts, and found evidence for a regulatory role for a number of natural antisense transcripts. Specifically, we found that natural antisense transcripts for CCPG1 and RAPGEF3 may functionally disrupt signaling pathways and corresponding biological phenotypes, such as cell viability, either independently or in parallel with the corresponding sense transcript. Our results show that the large-scale siRNA screen can be applied to evaluate natural antisense transcript modulation of fundamental cellular events.
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