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Puri S, Kenyon BM, Hamrah P. Immunomodulatory Role of Neuropeptides in the Cornea. Biomedicines 2022; 10:1985. [PMID: 36009532 PMCID: PMC9406019 DOI: 10.3390/biomedicines10081985] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 12/21/2022] Open
Abstract
The transparency of the cornea along with its dense sensory innervation and resident leukocyte populations make it an ideal tissue to study interactions between the nervous and immune systems. The cornea is the most densely innervated tissue of the body and possesses both immune and vascular privilege, in part due to its unique repertoire of resident immune cells. Corneal nerves produce various neuropeptides that have a wide range of functions on immune cells. As research in this area expands, further insights are made into the role of neuropeptides and their immunomodulatory functions in the healthy and diseased cornea. Much remains to be known regarding the details of neuropeptide signaling and how it contributes to pathophysiology, which is likely due to complex interactions among neuropeptides, receptor isoform-specific signaling events, and the inflammatory microenvironment in disease. However, progress in this area has led to an increase in studies that have begun modulating neuropeptide activity for the treatment of corneal diseases with promising results, necessitating the need for a comprehensive review of the literature. This review focuses on the role of neuropeptides in maintaining the homeostasis of the ocular surface, alterations in disease settings, and the possible therapeutic potential of targeting these systems.
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Affiliation(s)
- Sudan Puri
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Brendan M. Kenyon
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Pedram Hamrah
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
- Departments of Immunology and Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
- Cornea Service, Tufts New England Eye Center, Boston, MA 02111, USA
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2
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Bo Q, Yang F, Li Y, Meng X, Zhang H, Zhou Y, Ling S, Sun D, Lv P, Liu L, Shi P, Tian C. Structural insights into the activation of somatostatin receptor 2 by cyclic SST analogues. Cell Discov 2022; 8:47. [PMID: 35595746 PMCID: PMC9122944 DOI: 10.1038/s41421-022-00405-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 03/23/2022] [Indexed: 11/09/2022] Open
Abstract
The endogenous cyclic tetradecapeptide SST14 was reported to stimulate all five somatostatin receptors (SSTR1-5) for hormone release, neurotransmission, cell growth arrest and cancer suppression. Two SST14-derived short cyclic SST analogues (lanreotide or octreotide) with improved stability and longer lifetime were developed as drugs to preferentially activate SSTR2 and treat acromegalia and neuroendocrine tumors. Here, cryo-EM structures of the human SSTR2-Gi complex bound with SST14, octreotide or lanreotide were determined at resolutions of 2.85 Å, 2.97 Å, and 2.87 Å, respectively. Structural and functional analysis revealed that interactions between β-turn residues in SST analogues and transmembrane SSTR2 residues in the ligand-binding pocket are crucial for receptor binding and functional stimulation of the two SST14-derived cyclic octapeptides. Additionally, Q1022.63, N2766.55, and F2947.35 could be responsible for the selectivity of lanreotide or octreotide for SSTR2 over SSTR1 or SSTR4. These results provide valuable insights into further rational development of SST analogue drugs targeting SSTR2.
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Affiliation(s)
- Qing Bo
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Fan Yang
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Yingge Li
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Xianyu Meng
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Huanhuan Zhang
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Yingxin Zhou
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Shenglong Ling
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Demeng Sun
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Pei Lv
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China
| | - Lei Liu
- Tsinghua-Peking Joint Center for Life Sciences, Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China.
| | - Pan Shi
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China.
| | - Changlin Tian
- Department of Chemistry and the First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, Anhui Engineering Laboratory of Peptide Drug, Anhui Laboratory of Advanced Photonic Science and Technology, University of Science and Technology of China, Hefei, Anhui, China. .,High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui, China.
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3
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Krug S, Mordhorst JP, Moser F, Theuerkorn K, Ruffert C, Egidi M, Rinke A, Gress TM, Michl P. Interaction between somatostatin analogues and targeted therapies in neuroendocrine tumor cells. PLoS One 2019; 14:e0218953. [PMID: 31237925 PMCID: PMC6592550 DOI: 10.1371/journal.pone.0218953] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 06/12/2019] [Indexed: 01/17/2023] Open
Abstract
Somatostatin analogues (SSA) represent the standard of care for symptom control in patients with functional gastro-entero-pancreatic neuroendocrine tumors (GEP-NET). In addition, SSA exert significant anti-proliferative effects in mid-gut and pancreatic NET (PanNET). In parallel, molecularly targeted therapies (MTT) have been shown to improve progression free survival (PFS) in patients with PanNET. However, due to either primary or acquired resistance to MTT, their impact on overall survival (OS) remains unclear. To date, various hypotheses exist to explain differences in patient responsiveness to SSA and MTT. However, data addressing one of the most pivotal questions, whether combining SSA with novel MTT will result in synergistic or additive efficacy compared to monotherapy, are lacking. The aim of this study is to characterize the interaction, optimal sequence and dosing of SSA-based and molecularly targeted therapies in PanNET. Somatostatin receptor subtypes 1–5 (SSTR) were evaluated in the neuroendocrine cell lines Bon1, QGP1 and Ins-1 via immunoblot and qRT-PCR. The impact of the SSA-analogue lanreotide alone or in combination with the MTT sunitinib, everolimus and regorafenib on intracellular signalling, hormone secretion and cell proliferation was determined in cell lysates and supernatants. In addition, synergistic effects of SSA and MTT in various sequential therapeutic approaches were investigated. SSTR were differently expressed in the examined neuroendocrine tumor cell lines. SSTR modulation via lanreotide moderately influenced proliferation, mainly via modulating AKT and ERK signalling, which was paralleled by decreased chromogranin A (CgA) expression and secretion. Interestingly, MTT treatment with regorafenib upregulated the expression of SSTR-2 and -5, while sunitinib and everolimus did not significantly alter SSTR expression. Cell viability was significantly reduced by all MTT, with regorafenib exerting the most significant effects. However, compared to the marked effects of MTT alone, synergistic effects of combined MTT and lanreotide treatment were only modest and time- and dose-dependent. SSTR are differentially expressed in various NEN cell lines. Their expression is influenced by MTT treatment. Various sequential or simultaneous combinations of lanreotide and MTT did not lead to significant synergistic effects.
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Affiliation(s)
- Sebastian Krug
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
- Department of Gastroenterology and Endocrinology, Philipps-University, Marburg, Germany
| | - Jan-Philipp Mordhorst
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
| | - Fabian Moser
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
| | - Katharina Theuerkorn
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
| | - Claudia Ruffert
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
| | - Maren Egidi
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
| | - Anja Rinke
- Department of Gastroenterology and Endocrinology, Philipps-University, Marburg, Germany
| | - Thomas M. Gress
- Department of Gastroenterology and Endocrinology, Philipps-University, Marburg, Germany
| | - Patrick Michl
- Department of Internal Medicine I, Martin Luther University Halle/Wittenberg, Halle (Saale), Germany
- * E-mail:
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Zhao Y, Peng L, Li X, Zhang Y. Expression of somatostatin and its receptor 1-5 in endometriotic tissues and cells. Exp Ther Med 2018; 16:3777-3784. [PMID: 30405748 PMCID: PMC6201141 DOI: 10.3892/etm.2018.6730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/09/2018] [Indexed: 12/23/2022] Open
Abstract
The present study aimed to detect the expression of somatostatin (SS) and SS receptor (SSTR)1-5 in tissues from patients with endometriosis (EMS). Reverse transcription-quantitative polymerase chain reaction analysis was applied to examine the expression of somatostatin gene in ectopic endometrial cells (EECs). The expression of somatostatin receptor 1–5 in the ectopic endometrium (EE), eutopic endometrium and normal endometrium and their association with EMS staging were determined by immunohistochemistry. The results indicated that the expression of SS in EECs was significantly higher compared with that in the control group. SSTR1-5 were expressed in the EE tissues from 30 patients with EMS, and the positive rates were 43.3, 70.0, 53.3, 50.0 and 96.7%, respectively, which were closely associated with EMS staging of the patients. The positive rates of SSTR1-5 expression in the eutopic endometrium from 12 patients with EMS were 33.3, 41.7, 58.3, 58.3 and 83.3%, respectively, while the positive rates of SSTR1-5 expression in the normal endometrium from 14 women without EMS were 7.1, 7.1, 21.4, 28.6 and 64.3%, which were lower than the positive rates of SSTR1-5 in the EE (43.3, 70, 53.3, 50 and 96.7%) and eutopic endometrial cells (33.3, 41.7, 58.3, 58.3 and 83.3%). In conclusion, SS was highly expressed in EECs. SSTR1-5 were expressed in the ectopic as well as eutopic endometrium, and low or moderate expression of SSTR1-4 and high expression of SSTR5 were detected in the ectopic and eutopic endometrial tissues, while low expression of SSTR1-4 and partial expression of SSTR5 were detected in normal endometrium. The positive rates of expression of SSTR1-5 in the EE cells and eutopic endometrium were higher than those in the normal endometrium. The expression of all the subtypes of SSTR in the EE tissues was closely associated with EMS staging.
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Affiliation(s)
- Yanhua Zhao
- Department of Obstetrics and Gynecology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Lin Peng
- Reproductive and Stem Cell Research Institute, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Xiang Li
- Department of Pathology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Yi Zhang
- Department of Obstetrics and Gynecology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
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Garbuzenko DV, Arefyev NO, Kazachkov EL. Antiangiogenic therapy for portal hypertension in liver cirrhosis: Current progress and perspectives. World J Gastroenterol 2018; 24:3738-3748. [PMID: 30197479 PMCID: PMC6127663 DOI: 10.3748/wjg.v24.i33.3738] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/09/2018] [Accepted: 07/16/2018] [Indexed: 02/06/2023] Open
Abstract
Developing medicines for hemodynamic disorders that are characteristic of cirrhosis of the liver is a relevant problem in modern hepatology. The increase in hepatic vascular resistance to portal blood flow and subsequent hyperdynamic circulation underlie portal hypertension (PH) and promote its progression, despite the formation of portosystemic collaterals. Angiogenesis and vascular bed restructurization play an important role in PH pathogenesis as well. In this regard, strategic directions in the therapy for PH in cirrhosis include selectively decreasing hepatic vascular resistance while preserving or increasing portal blood flow, and correcting hyperdynamic circulation and pathological angiogenesis. The aim of this review is to describe the mechanisms of angiogenesis in PH and the methods of antiangiogenic therapy. The PubMed database, the Google Scholar retrieval system, and the reference lists from related articles were used to search for relevant publications. Articles corresponding to the aim of the review were selected for 2000-2017 using the keywords: “liver cirrhosis”, “portal hypertension”, “pathogenesis”, “angiogenesis”, and “antiangiogenic therapy”. Antiangiogenic therapy for PH was the inclusion criterion. In this review, we have described angiogenesis inhibitors and their mechanism of action in relation to PH. Although most of them were studied only in animal experiments, this selective therapy for abnormally growing newly formed vessels is pathogenetically reasonable to treat PH and associated complications.
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Affiliation(s)
| | - Nikolay Olegovich Arefyev
- Department of Pathological Anatomy and Forensic Medicine, South Ural State Medical University, Chelyabinsk 454092, Russia
| | - Evgeniy Leonidovich Kazachkov
- Department of Pathological Anatomy and Forensic Medicine, South Ural State Medical University, Chelyabinsk 454092, Russia
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Mohamed A, Romano D, Saveanu A, Roche C, Albertelli M, Barbieri F, Brue T, Niccoli P, Delpero JR, Garcia S, Ferone D, Florio T, Moutardier V, Poizat F, Barlier A, Gerard C. Anti-proliferative and anti-secretory effects of everolimus on human pancreatic neuroendocrine tumors primary cultures: is there any benefit from combination with somatostatin analogs? Oncotarget 2017; 8:41044-41063. [PMID: 28454119 PMCID: PMC5522327 DOI: 10.18632/oncotarget.17008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 03/22/2017] [Indexed: 11/25/2022] Open
Abstract
Therapeutic management of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) is challenging. The mammalian target of rapamycin (mTOR) inhibitor everolimus recently obtained approval from the Food and Drug Administration for the treatment of patients with advanced pancreatic neuroendocrine tumors (pNETs). Despite its promising antitumor efficacy observed in cell lines, clinical benefit for patients is unsatisfactory. The limited therapeutic potential of everolimus in cancer cells has been attributed to Akt activation due to feedback loops relief following mTOR inhibition. Combined inhibition of Akt might then improve everolimus antitumoral effect. In this regard, the somatostatin analog (SSA) octreotide has been shown to repress the PI3K/Akt pathway in some tumor cell lines. Moreover, SSAs are well tolerated and routinely used to reduce symptoms caused by peptide release in patients carrying functional GEP-NETs. We have recently established and characterized primary cultures of human pNETs and demonstrated the anti-proliferative effects of both octreotide and pasireotide. In this study, we aim at determining the antitumor efficacy of everolimus alone or in combination with the SSAs octreotide and pasireotide in primary cultures of pNETs. Everolimus reduced both Chromogranin A secretion and cell viability and upregulated Akt activity in single treatment. Its anti-proliferative and anti-secretory efficacy was not improved combined with the SSAs. Both SSAs did not overcome everolimus-induced Akt upregulation. Furthermore, caspase-dependent apoptosis induced by SSAs was lost in combined treatments. These molecular events provide the first evidence supporting the lack of marked benefit in patients co-treated with everolimus and SSA.
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Affiliation(s)
- Amira Mohamed
- Aix Marseille Univ, CNRS, CRN2M, Marseille, France
- APHM, Conception Hospital, Molecular Biology Laboratory, Marseille, France
| | - David Romano
- Aix Marseille Univ, CNRS, CRN2M, Marseille, France
| | - Alexandru Saveanu
- Aix Marseille Univ, CNRS, CRN2M, Marseille, France
- APHM, Conception Hospital, Molecular Biology Laboratory, Marseille, France
| | - Catherine Roche
- APHM, Conception Hospital, Molecular Biology Laboratory, Marseille, France
| | - Manuela Albertelli
- Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genova, Genova, Italy
| | - Federica Barbieri
- Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genova, Genova, Italy
| | - Thierry Brue
- Aix Marseille Univ, CNRS, CRN2M, Marseille, France
- APHM, Conception Hospital, Endocrinology Department, Marseille, France
| | - Patricia Niccoli
- Paoli Calmettes Cancer Institute, Oncology Department, IPC CoE-ENETS, Marseille, France
| | - Jean-Robert Delpero
- Paoli Calmettes Cancer Institute, Surgery Department, IPC CoE-ENETS, Marseille, France
| | - Stephane Garcia
- APHM, North Hospital, Pathology Laboratory, Marseille, France
| | - Diego Ferone
- Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genova, Genova, Italy
| | - Tullio Florio
- Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genova, Genova, Italy
| | | | - Flora Poizat
- Paoli Calmettes Cancer Institute, Biopathology Department, IPC CoE-ENETS, Marseille, France
| | - Anne Barlier
- Aix Marseille Univ, CNRS, CRN2M, Marseille, France
- APHM, Conception Hospital, Molecular Biology Laboratory, Marseille, France
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Cambiaghi V, Vitali E, Morone D, Peverelli E, Spada A, Mantovani G, Lania AG. Identification of human somatostatin receptor 2 domains involved in internalization and signaling in QGP-1 pancreatic neuroendocrine tumor cell line. Endocrine 2017; 56:146-157. [PMID: 27406390 DOI: 10.1007/s12020-016-1026-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 06/16/2016] [Indexed: 01/14/2023]
Abstract
Somatostatin exerts inhibitory effects on hormone secretion and cell proliferation via five receptor subtypes (SST1-SST5), whose internalization is regulated by β-arrestins. The receptor domains involved in these effects have been only partially elucidated. The aim of the study is to characterize the molecular mechanism and determinants responsible for somatostatin receptor 2 internalization and signaling in pancreatic neuroendocrine QGP-1 cell line, focusing on the third intracellular loop and carboxyl terminal domains. We demonstrated that in cells transfected with somatostatin receptor 2 third intracellular loop mutant, no differences in β-arrestins recruitment and receptor internalization were observed after somatostatin receptor 2 activation in comparison with cells bearing wild-type somatostatin receptor 2. Conversely, the truncated somatostatin receptor 2 failed to recruit β-arrestins and to internalize after somatostatin receptor 2 agonist (BIM23120) incubation. Moreover, the inhibitory effect of BIM23120 on cell proliferation, cyclin D1 expression, P-ERK1/2 levels, apoptosis and vascular endothelial growth factor secretion was completely lost in cells transfected with either third intracellular loop or carboxyl terminal mutants. In conclusion, we demonstrated that somatostatin receptor 2 internalization requires intact carboxyl terminal while the effects of SS on cell proliferation, angiogenesis and apoptosis mediated by somatostatin receptor 2 need the integrity of both third intracellular loop and carboxyl terminal.
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Affiliation(s)
- Valeria Cambiaghi
- Laboratory of Cellular and Molecular Endocrinology, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Eleonora Vitali
- Laboratory of Cellular and Molecular Endocrinology, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Diego Morone
- Laboratory of Cellular and Molecular Endocrinology, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Erika Peverelli
- Endocrine Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Anna Spada
- Endocrine Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Giovanna Mantovani
- Endocrine Unit, Department of Clinical Sciences and Community Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - Andrea Gerardo Lania
- Endocrine Unit, Humanitas Clinical and Research Center, Rozzano, Italy.
- Humanitas University, School of Medicine, Rozzano, Italy.
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Han H, Son S, Son S, Kim N, Yhee JY, Lee JH, Choi JS, Joo CK, Lee H, Lee D, Kim WJ, Kim SH, Kwon IC, Kim H, Kim K. Reducible Polyethylenimine Nanoparticles for Efficient siRNA Delivery in Corneal Neovascularization Therapy. Macromol Biosci 2016; 16:1583-1597. [DOI: 10.1002/mabi.201600051] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 07/14/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Hyounkoo Han
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
- Department of Chemical and Biomolecular Engineering; Sogang University; Shinsu-dong Mapo-gu Seoul 121-742 South Korea
| | - Sohee Son
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
| | - Sejin Son
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
| | - Namho Kim
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
| | - Ji Young Yhee
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
| | - Jae Hyeop Lee
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
- Department of Chemical and Biomolecular Engineering; Sogang University; Shinsu-dong Mapo-gu Seoul 121-742 South Korea
| | - Jun-Sub Choi
- Department of Ophthalmology and Visual Science; Seoul St. Mary's Hospital; College of Medicine; The Catholic University of Korea; 505, Banpo-dong Seocho-gu Seoul 137-040 South Korea
| | - Choun-Ki Joo
- Department of Ophthalmology and Visual Science; Seoul St. Mary's Hospital; College of Medicine; The Catholic University of Korea; 505, Banpo-dong Seocho-gu Seoul 137-040 South Korea
| | - Hohyeon Lee
- Department of Chemical and Biomolecular Engineering; Sogang University; Shinsu-dong Mapo-gu Seoul 121-742 South Korea
| | - Duhwan Lee
- Center for Self-Assembly and Complexity; Institute for Basic Science (IBS); Pohang 790-784 South Korea
- Department of Chemistry Polymer Research Institute; Pohang University of Science and Technology (POSTECH); Pohang 790-784 South Korea
| | - Won Jong Kim
- Center for Self-Assembly and Complexity; Institute for Basic Science (IBS); Pohang 790-784 South Korea
- Department of Chemistry Polymer Research Institute; Pohang University of Science and Technology (POSTECH); Pohang 790-784 South Korea
| | - Sun Hwa Kim
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
| | - Ick Chan Kwon
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
| | - Hyuncheol Kim
- Department of Chemical and Biomolecular Engineering; Sogang University; Shinsu-dong Mapo-gu Seoul 121-742 South Korea
| | - Kwangmeyung Kim
- Center for Theragnosis; Biomedical Research Institute Korea Institute of Science and Technology (KIST); Hwarangno 14-gil 6 Seongbuk-gu Seoul 136-791 South Korea
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Abstract
Neuroendocrine tumors (NET) are characterized by a high over-expression of many different peptide hormone receptors. These receptors represent important molecular targets for imaging and therapy, using either radiolabeled or cold peptide analogs. The clinically best established example is somatostatin receptor targeting. A relatively new application is glucagon-like peptide 1 (GLP-1) receptor-targeted imaging of insulinomas, which is highly sensitive. A potential future candidate for peptide receptor targeting is the gastric inhibitory peptide (GIP) receptor. It was recently found to exhibit a very wide expression in NET and may be a particularly suitable target in somatostatin and GLP-1 receptor negative tumors. With increasing use of peptide receptor targeting, reliable morphologic in vitro tools to assess peptide receptors in tissues are mandatory, such as in vitro receptor autoradiography or thoroughly established immunohistochemical procedures.
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Affiliation(s)
- Meike Körner
- Pathologie Länggasse, CH-3001 Bern, Switzerland.
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10
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Abstract
Neuroendocrine tumours (NETs) represent a less frequent and heterogeneous group of tumours, which has experienced, in recent years, a significant increase in effective therapeutic possibilities overcoming the disappointing results from chemotherapy. Initial improvements in treatment strategies came from somatostatin analogues (SSAs) that have widely demonstrated a significant improvement in symptomatic relief and tumour control growth by a complex mechanism of action over cell survival, angiogenesis and immunomodulation. Recent investigations have pointed out novel SSAs with a wider binding profile (pasireotide), chimeric molecules against somatostatin receptors and dopamine receptors and the combination with targeted agents, such as mTOR inhibitors or antiangiogenic agents. Immunotherapy is the second cornerstone in NET treatment and has been represented with interferon alpha for a long time, with a demonstrated activity on tumour and clinical response. Its less manageable adverse events have limited its usage. However, different checkpoints in immune system regulation have been effectively targeted in different solid tumours, and novel approaches are currently arising in NETs. In conclusion, biotherapy remains an active treatment strategy for initial approach in patients with NETs. Further investigation on patients' selection, molecular profiles, treatment sequence or combination and optimisation of current and novel biotherapy agents is required.
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Affiliation(s)
- T Alonso-Gordoa
- Medical Oncology DepartmentRamón y Cajal University Hospital, Carretera de Colmenar Km 9,100, 28034 Madrid, SpainMedical Oncology DepartmentVall d'Hebrón University Hospital, Passeig de la Vall d'Hebrón, 119-129, 08035 Barcelona, Spain
| | - J Capdevila
- Medical Oncology DepartmentRamón y Cajal University Hospital, Carretera de Colmenar Km 9,100, 28034 Madrid, SpainMedical Oncology DepartmentVall d'Hebrón University Hospital, Passeig de la Vall d'Hebrón, 119-129, 08035 Barcelona, Spain
| | - E Grande
- Medical Oncology DepartmentRamón y Cajal University Hospital, Carretera de Colmenar Km 9,100, 28034 Madrid, SpainMedical Oncology DepartmentVall d'Hebrón University Hospital, Passeig de la Vall d'Hebrón, 119-129, 08035 Barcelona, Spain
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11
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Mozziconacci O, Schöneich C. Effect of Conformation on the Photodegradation of Trp- And Cystine-Containing Cyclic Peptides: Octreotide and Somatostatin. Mol Pharm 2014; 11:3537-46. [DOI: 10.1021/mp5003174] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Olivier Mozziconacci
- Department of Pharmaceutical
Chemistry, University of Kansas, 2095 Constant Avenue, Lawrence, Kansas 66047, United States
| | - Christian Schöneich
- Department of Pharmaceutical
Chemistry, University of Kansas, 2095 Constant Avenue, Lawrence, Kansas 66047, United States
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12
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Reubi JC, Schonbrunn A. Illuminating somatostatin analog action at neuroendocrine tumor receptors. Trends Pharmacol Sci 2013; 34:676-88. [PMID: 24183675 DOI: 10.1016/j.tips.2013.10.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/26/2013] [Accepted: 10/03/2013] [Indexed: 02/08/2023]
Abstract
Somatostatin analogs for the diagnosis and therapy of neuroendocrine tumors (NETs) have been used in clinical applications for more than two decades. Five somatostatin receptor subtypes have been identified and molecular mechanisms of somatostatin receptor signaling and regulation have been elucidated. These advances increased understanding of the biological role of each somatostatin receptor subtype, their distribution in NETs, as well as agonist-specific regulation of receptor signaling, internalization, and phosphorylation, particularly for the sst2 receptor subtype, which is the primary target of current somatostatin analog therapy for NETs. Various hypotheses exist to explain differences in patient responsiveness to somatostatin analog inhibition of tumor secretion and growth as well as differences in the development of tumor resistance to therapy. In addition, we now have a better understanding of the action of both first generation (octreotide, lanreotide, Octreoscan) and second generation (pasireotide) FDA-approved somatostatin analogs, including the biased agonistic character of some agonists. The increased understanding of somatostatin receptor pharmacology provides new opportunities to design more sophisticated assays to aid the future development of somatostatin analogs with increased efficacy.
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Affiliation(s)
- Jean Claude Reubi
- Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland.
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13
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Hypoxia effects on proangiogenic factors in human umbilical vein endothelial cells: functional role of the peptide somatostatin. Naunyn Schmiedebergs Arch Pharmacol 2011; 383:593-612. [DOI: 10.1007/s00210-011-0625-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 03/23/2011] [Indexed: 12/15/2022]
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14
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Burman P, Besjakov J, Svensjö T. Large fat and skin necroses after deep subcutaneous injections of a slow-release somatostatin analogue in a woman with acromegaly. Growth Horm IGF Res 2010; 20:438-440. [PMID: 21071248 DOI: 10.1016/j.ghir.2010.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Revised: 10/17/2010] [Accepted: 10/17/2010] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Somatostatin analogues are the most commonly used drugs for treatment of acromegaly. Known side effects include gastrointestinal reactions, cholelithiasis, effects on glucose metabolism, and mild reactions at injection sites. We report a patient who developed fat and skin necroses after injections of a depot somatostatin analogue. SUBJECT A woman with active acromegaly was given deep subcutaneous injections of an extended release formulation of lanreotide at alternate sides of the buttocks on three occasions over a ten week period. The regimen was then discontinued due to gastrointestinal complaints. One month later indurated subcutaneous nodules appeared at both sites. After another two months, the patient presented 10×10 cm lesions on the buttocks, with central erythematous zones and, at the site of two injections, a necrotic 5×3 cm ulcer. There were no signs of infection or systemic diseases. MRI revealed bilateral fat necroses. A month later, an ulcer developed at the second site. The ulcers were managed conservatively until clear demarcations were obtained, where after surgical revisions were performed. Eight months after the last injection, the wounds could be closed. CONCLUSION The fat and skin necroses represent a side-effect not previously described after deep subcutaneous injections. Possibly, the patient had an exceptional susceptibility to develop an inflammatory, foreign-body like reaction that hypothetically was aggravated by a sustained anti-angiogenic effect of the compound.
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Affiliation(s)
- Pia Burman
- Department of Endocrinology, University Hospital, SE-205 02 Malmö, Sweden.
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15
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Oberg KE, Reubi JC, Kwekkeboom DJ, Krenning EP. Role of somatostatins in gastroenteropancreatic neuroendocrine tumor development and therapy. Gastroenterology 2010; 139:742-53, 753.e1. [PMID: 20637207 DOI: 10.1053/j.gastro.2010.07.002] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Revised: 07/06/2010] [Accepted: 07/08/2010] [Indexed: 12/02/2022]
Abstract
The incidence and prevalence of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) have increased in the past 20 years. GEP-NETs are heterogeneous tumors, in terms of clinical and biological features, that originate from the pancreas or the intestinal tract. Some GEP-NETs grow very slowly, some grow rapidly and do not cause symptoms, and others cause hormone hypersecretion and associated symptoms. Most GEP-NETs overexpress receptors for somatostatins. Somatostatins inhibit the release of many hormones and other secretory proteins; their effects are mediated by G protein-coupled receptors that are expressed in a tissue-specific manner. Most GEP-NETs overexpress the somatostatin receptor SSTR2; somatostatin analogues are the best therapeutic option for functional neuroendocrine tumors because they reduce hormone-related symptoms and also have antitumor effects. Long-acting formulations of somatostatin analogues stabilize tumor growth over long periods. The development of radioactive analogues for imaging and peptide receptor radiotherapy has improved the management of GEP-NETs. Peptide receptor radiotherapy has significant antitumor effects, increasing overall survival times of patients with tumors that express a high density of SSTRs, particularly SSTR2 and SSTR5. The multi-receptor somatostatin analogue SOM230 (pasireotide) and chimeric molecules that bind SSTR2 and the dopamine receptor D2 are also being developed to treat patients with GEP-NETs. Combinations of radioactive labeled and unlabeled somatostatin analogues and therapeutics that inhibit other signaling pathways, such as mammalian target of rapamycin (mTOR) and vascular endothelial growth factor, might be the most effective therapeutics for GEP-NETs.
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Affiliation(s)
- Kjell E Oberg
- Department of Endocrine Oncology, University Hospital, Uppsala, Sweden.
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16
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Abstract
OBJECTIVES This supplement represents the proceedings of a panel of investigators whose goal was to assess the quality of evidence pertaining to current therapeutic approaches in the management of neuroendocrine tumors (NETs). It will examine the differences in opinions between expert faculty and community physicians. METHODS The Neuroendocrine Tumors Summit convened in December 2009 to address 6 statements prepared by panel members that reflect important questions in the management of NETs. RESULTS Panel members were polled on their acceptance of each statement, and those results were compared with community-based oncologists, gastroenterologists, and endocrinologists. CONCLUSIONS More education regarding the treatment of NETs, including pertinent studies, is needed for physicians. Additional multicenter, prospective, placebo-controlled trials are necessary to demonstrate the benefits of somatostatin analogs, including their ability to control symptoms and affect tumor growth, and their synergistic effect with other therapies. New trials should be reported consistently and include time to tumor progression and progression-free survival as primary or secondary end points.
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Zhao R, Yang W, Wang Z, Li G, Qin W, Wang J. Treatment of transplanted tumor of lung adenocarcinoma A549 transfected by human somatostatin receptor subtype 2 (hsstr2) gene with 188Re-RC-160. Nucl Med Biol 2010; 37:977-87. [PMID: 21055629 DOI: 10.1016/j.nucmedbio.2010.05.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2010] [Revised: 05/18/2010] [Accepted: 05/21/2010] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIM Radionuclide-labeled somatostatin analogues selectively target somatostatin receptor (SSTR)-expressing tumors as a basis for diagnosis and treatment of these tumors. To those tumors without somatostatin receptor expressed, the hSSTR2 gene was transfected. Express of the hSSTR2 receptor was imaging and the radiotherapeutic effect was evaluated with (188)Re-RC-160. METHODS The stable hSSTR2-expressing A549 cells (pcDNA3-hSSTR2 A549) and non-somatostatin receptor expressing A549 cells (pcDNA3 A549) were selected by western blot. Later, a corresponding animal tumor model was established. Expression of the hSSTR2 reporter was imaged using (188)Re-RC-160 recognition. Tumors were evaluated for somatostatin receptor expression using immunohistochemistry. The distribution of (188)Re-RC-160 in the animal tumor model was measured and the inhibitory effects of (188)Re-RC-160 were evaluated by measurement of tumor growth and hematoxylin and eosin and TdT mediated dUTP nick end labeling (TUNEL) staining. RESULTS In vivo radioimaging revealed specific targeting of (188)Re-RC-160 to tumors derived from pcDNA3- hSSTR2 A549 cells, compared to those from pcDNA3 A549 cells. pcDNA3- hSSTR2 A549 tumor growth inhibition was significantly higher in the single 7.4 MBq (188)Re-RC-160 treatment group than in the 2×7.4 MBq rhenium-188, RC-160 group, control group, and pcDNA3 A549 tumors (P<.05). Furthermore, treatment fractionation group (2 × 7.4 MBq (188)Re-RC-160), induced significantly increased tumor-growth inhibition compare with single 7.4 MBq (188)Re-RC-160 treatment (P<.05). CONCLUSION These studies showed that (188)Re-RC-160 could be effectively used for targeting therapy the A549-derived tumors exogenously expressing hSSTR2, which will offers a potential therapeutic strategy for the treatment of somatostatin receptor-negative cancers.
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Affiliation(s)
- Rong Zhao
- Department of Nuclear Medicine, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China
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Dall'igna P, Cecchetto G, Bisogno G, Conte M, Chiesa PL, D'Angelo P, De Leonardis F, De Salvo G, Favini F, Ferrari A. Pancreatic tumors in children and adolescents: the Italian TREP project experience. Pediatr Blood Cancer 2010; 54:675-80. [PMID: 19998473 DOI: 10.1002/pbc.22385] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Malignant pancreatic tumors are exceedingly rare in pediatric age and their clinical features and treatment usually go unappreciated by most pediatric oncologists and surgeons. METHODS From January 2000 to July 2009, 21 patients <18 years old with pancreatic tumors were prospectively registered in the Italian cooperative TREP project dedicated to very rare pediatric tumors. RESULTS Tumor types were 4 pancreatoblastomas, 2 pancreatic carcinomas, 3 neoplasms of the endocrine pancreas, and 12 solid pseudopapillary tumors. Three of the four patients with pancreatoblastoma had advanced disease at diagnosis and were given chemotherapy; at the time of this report, three patients were alive in first remission, while one died due to treatment toxicity. Both the cases of pancreatic carcinoma had the acinar cell subtype and successfully underwent pancreaticoduodenectomy with complete tumor resection, remaining without evidence of disease at the time of this analysis. The histological diagnoses of the three endocrine tumors were a malignant islet cell tumor, a gastrinoma, and a well-differentiated tumor. All 12 patients with solid pseudopapillary tumors underwent complete tumor resection and were given no adjuvant treatment; 11 were alive in first remission, while one experienced a local and distant relapse 5 years after diagnosis. CONCLUSIONS Surgery remains the keystone of treatment for pancreatic tumors in pediatric age as in adults. The TREP project shows that prospective cooperative studies are feasible even for such very rare tumors as these and may serve as a model for developing international cooperative schemes.
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19
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Combination therapy in A549 cells. Nucl Med Biol 2010; 37:317-26. [DOI: 10.1016/j.nucmedbio.2009.11.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Revised: 11/26/2009] [Accepted: 11/27/2009] [Indexed: 11/22/2022]
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Thrombospondin-1 is a critical effector of oncosuppressive activity of sst2 somatostatin receptor on pancreatic cancer. Proc Natl Acad Sci U S A 2009; 106:17769-74. [PMID: 19805200 DOI: 10.1073/pnas.0908674106] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The somatostatin receptor subtype 2 (sst2) behaves as a tumor suppressor when expressed and stimulated by its ligand somatostatin in pancreatic cancer. We reveal a mechanism underlying oncosuppressive action of sst2, whereby this inhibitory receptor upregulates the expression of the secreted angioinhibitory factor thrombospondin-1 (TSP-1), as demonstrated in exocrine BxPC-3 and endocrine BON pancreatic cancer cells. The sst2-dependent upregulation of TSP-1 occurs through the inhibition of the PI3K pathway. It depends on transcriptional and translational events, involving a previously undescribed IRES in the 5'-UTR of TSP-1 mRNA. Chick chorioallantoic membrane was used as an in vivo model to demonstrate that TSP-1 is a critical effector of the inhibitory role of sst2 on the neoangiogenesis and oncogenesis induced by pancreatic cancer cells. TSP-1 reduced in vitro tubulogenesis of endothelial cells when grown in conditioned medium from pancreatic cancer cells expressing sst2, as compared to those expressing the control vector. TSP-1 inhibited tumor cell-induced neoangiogenesis by directly sequestering the proangiogenic factor VEGF, and inactivating the angiogenesis initiated by VEGFR2 phosphorylation in endothelial cells. Using human pancreatic tissue-microarrays, the expression of both sst2 and TSP-1 was shown to be correlated during the pancreatic neoplastic program. Both proteins are nearly undetectable in normal exocrine pancreas and in most invasive cancer lesions, but their expression is strikingly upregulated in most preinvasive cancer-adjacent lesions. The upregulation of both sst2 and TSP-1 tumor suppressors may function as an early negative feedback to restrain pancreatic carcinogenesis.
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Pyronnet S, Bousquet C, Najib S, Azar R, Laklai H, Susini C. Antitumor effects of somatostatin. Mol Cell Endocrinol 2008; 286:230-7. [PMID: 18359151 DOI: 10.1016/j.mce.2008.02.002] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 01/15/2008] [Accepted: 02/02/2008] [Indexed: 02/07/2023]
Abstract
Since its discovery three decades ago as an inhibitor of GH release from the pituitary gland, somatostatin has attracted much attention because of its functional role in the regulation of a wide variety of physiological functions in the brain, pituitary, pancreas, gastrointestinal tract, adrenals, thyroid, kidney and immune system. In addition to its negative role in the control of endocrine and exocrine secretions, somatostatin and analogs also exert inhibitory effects on the proliferation and survival of normal and tumor cells. Over the past 15 years, studies have begun to reveal some of the molecular mechanisms underlying the antitumor activity of somatostatin. This review covers the present knowledge in the antitumor effect of somatostatin and analogs and discusses the perspectives of novel clinical strategies based on somatostatin receptor sst2 gene transfer therapy.
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Affiliation(s)
- Stéphane Pyronnet
- INSERM U858, Institut de Médecine Moléculaire de Rangueil, Dpt Cancer/E16, CHU Rangueil, Toulouse Cedex 4, France
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22
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Mejias M, Garcia-Pras E, Tiani C, Bosch J, Fernandez M. The somatostatin analogue octreotide inhibits angiogenesis in the earliest, but not in advanced, stages of portal hypertension in rats. J Cell Mol Med 2008; 12:1690-9. [PMID: 18194463 PMCID: PMC3918085 DOI: 10.1111/j.1582-4934.2008.00218.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background: Angiogenesis is an important determinant of the pathophysiology of portal hypertension contributing to the formation of portosystemic collateral vessels and the hyperdynamic splanchnic circulation associated to this syndrome. Somatostatin and its analogues, like octreotide, have been shown to be powerful inhibitors of experimental angiogenesis. Aim: To determine whether octreotide has angioinhibitory effects in portal hypertensive rats. Methods: Partial portal vein-ligated (PPVL) rats were treated with octreotide or vehicle during 4 or 7 days. Splanchnic neovascularization and VEGF expression were determined by histological analysis and western blotting. Expression of the somatostatin receptor subtype 2 (SSTR2), which mediates the anti-angiogenic effects of octreotide, was also analyzed. Formation of portosystemic collaterals (radioactive microspheres) and hemodynamic parameters were also measured. Results: Octreotide treatment during 4 days markedly and significantly decreased splanchnic neovascularization, VEGF expression by 63% and portal pressure by 15%, whereas portosystemic collateralization and splanchnic blood flow were not modified. After 1 week of octreotide injection, portal pressure was reduced by 20%, but inhibition of angiogenesis escaped from octreotide therapy, a phenomenon that could be related to the finding that expression of SSTR2 receptor decreased progressively (up to 78% reduction) during the evolution of portal hypertension. Conclusion: This study provides the first experimental evidence showing that octreotide may be an effective anti-angiogenic therapy early after induction of portal hypertension, but not in advanced stages most likely due to SSTR2 down-regulation during the progression of portal hypertension in rats. These findings shed light on new mechanisms of action of octreotide in portal hypertension.
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Affiliation(s)
- Marc Mejias
- Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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Dimitroulopoulos D, Xinopoulos D, Tsamakidis K, Zisimopoulos A, Andriotis E, Panagiotakos D, Fotopoulou A, Chrysohoou C, Bazinis A, Daskalopoulou D, Paraskevas E. Long acting octreotide in the treatment of advanced hepatocellular cancer and overexpression of somatostatin receptors: randomized placebo-controlled trial. World J Gastroenterol 2007. [PMID: 17589893 DOI: 10.3748/wjg.v13.i13.3164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To estimate if and to what extent long acting octreotide (LAR) improves survival and quality of life in patients with advanced hepatocellular carcinoma (HCC). METHODS A total of 127 cirrhotics, stages A-B, due to chronic viral infections and with advanced HCC, were enrolled in the study. Scintigraphy with 111Indium labeled octreotide was performed in all cases. The patients with increased accumulation of radionuclear compound were randomized to receive either oral placebo only or octreotide/octreotide LAR only as follows: octreotide 0.5 mg s.c. every 8 h for 6 wk, at the end of wk 4-8 octreotide LAR 20 mg i.m. and at the end of wk 12 and every 4 wk octreotide LAR 30 mg i.m.. Follow-up was worked out monthly as well as the estimation of quality of life (QLQ-C30 questionnaire). Patients with negative somatostatin receptors (SSTR) detection were followed up in the same manner. RESULTS Scintigraphy demonstrated SSTR in 61 patients. Thirty were randomized to receive only placebo and 31 only octreotide. A significantly higher survival time was observed for the octreotide group (49+/-6 wk) as compared to the control group (28+/-1 wk) and to the SSTR negative group (28+/-2 wk), LR=20.39, df=2, P<0.01. The octreotide group presented 68.5% lower hazard ratio [95% CI (47.4%-81.2%)]. During the first year, a 22%, 39% and 43% decrease in the QLQ-C30 score was observed in each group, respectively. CONCLUSION The proposed therapeutic approach has shown to improve the survival and quality of life in SSTR positive patients with advanced HCC.
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Affiliation(s)
- D Dimitroulopoulos
- Liver Cancer Unit, Agios Savvas Cancer Hospital, 35 Parnassou str., GR-152 34 Halandri-Athens, and Laboratory of Biostatistics, Department of Nursing, University of Athens, Greece.
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24
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Dimitroulopoulos D, Xinopoulos D, Tsamakidis K, Zisimopoulos A, Andriotis E, Panagiotakos D, Fotopoulou A, Chrysohoou C, Bazinis A, Daskalopoulou D, Paraskevas E. Long acting octreotide in the treatment of advanced hepatocellular cancer and overexpression of somatostatin receptors: Randomized placebo-controlled trial. World J Gastroenterol 2007; 13:3164-70. [PMID: 17589893 PMCID: PMC4436600 DOI: 10.3748/wjg.v13.i23.3164] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To estimate if and to what extent long acting octreotide (LAR) improves survival and quality of life in patients with advanced hepatocellular carcinoma (HCC).
METHODS: A total of 127 cirrhotics, stages A-B, due to chronic viral infections and with advanced HCC, were enrolled in the study. Scintigraphy with 111Indium labeled octreotide was performed in all cases. The patients with increased accumulation of radionuclear compound were randomized to receive either oral placebo only or octreotide/octreotide LAR only as follows: octreotide 0.5mg s.c. every 8 h for 6 wk, at the end of wk 4-8 octreotide LAR 20 mg i.m. and at the end of wk 12 and every 4 wk octreotide LAR 30mg i.m.. Follow-up was worked out monthly as well as the estimation of quality of life (QLQ-C30 questionnaire). Patients with negative somatostatin receptors (SSTR) detection were followed up in the same manner.
RESULTS: Scintigraphy demonstrated SSTR in 61 patients. Thirty were randomized to receive only placebo and 31 only octreotide. A significantly higher survival time was observed for the octreotide group (49 ± 6 wk) as compared to the control group (28 ± 1 wk) and to the SSTR negative group (28 ± 2 wk), LR = 20.39, df = 2, P < 0.01. The octreotide group presented 68.5% lower hazard ratio [95% CI (47.4%-81.2%)]. During the first year, a 22%, 39% and 43% decrease in the QLQ-C30 score was observed in each group respectively.
CONCLUSION: The proposed therapeutic approach has shown to improve the survival and quality of life in SSTR positive patients with advanced HCC.
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Affiliation(s)
- D Dimitroulopoulos
- Liver Cancer Unit, Agios Savvas Cancer Hospital, 35 Parnassou str., GR-152 34 Halandri-Athens, and Laboratory of Biostatistics, Department of Nursing, University of Athens, Greece.
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25
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Körner M, Reubi JC. NPY receptors in human cancer: a review of current knowledge. Peptides 2007; 28:419-25. [PMID: 17223228 DOI: 10.1016/j.peptides.2006.08.037] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Accepted: 08/20/2006] [Indexed: 11/26/2022]
Abstract
Many peptide hormone receptors are over-expressed in human cancer, permitting an in vivo targeting of tumors for diagnostic and therapeutic purposes. NPY receptors are novel and promising candidates in this field. Using in vitro receptor autoradiography, Y1 and Y2 receptors have been found to be expressed in breast carcinomas, adrenal gland and related tumors, renal cell carcinomas, and ovarian cancers in both tumor cells and tumor-associated blood vessels. Pathophysiologically, tumoral NPY receptors may be activated by endogenous NPY released from intratumoral nerve fibers or tumor cells themselves, and mediate NPY effects on tumor cell proliferation and tumoral blood supply. Clinically, tumoral NPY receptors may be targeted with NPY analogs coupled with adequate radionuclides or cytotoxic agents for a scintigraphic tumor imaging and/or tumor therapy.
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Affiliation(s)
- Meike Körner
- Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Bern, Murtenstrasse 31, PO Box 62, CH-3010 Bern, Switzerland
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26
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Sun LC, Luo J, Mackey LV, Fuselier JA, Coy DH. A conjugate of camptothecin and a somatostatin analog against prostate cancer cell invasion via a possible signaling pathway involving PI3K/Akt, αVβ3/αVβ5 and MMP-2/-9. Cancer Lett 2007; 246:157-66. [PMID: 16644105 DOI: 10.1016/j.canlet.2006.02.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Revised: 01/10/2006] [Accepted: 02/17/2006] [Indexed: 10/24/2022]
Abstract
Camptothecin (CPT) was conjugated to the N-terminal of a somatostatin analog (SSA) directly via a carbamate group and a basic N-terminal linking motif, D-Lys-D-Tyr-Lys-D-Tyr-D-Lys. This new CPT-SSA conjugate termed JF-10-81 was evaluated as a receptor-specific delivery system for its anti-invasive and anti-angiogenic activities. It was found that, in addition to blocking migration and invasion of highly invasive prostate cancer PC-3 cells, this conjugate also inhibited in vitro capillary-like tube formation of endothelial cells and in vivo angiogenesis in C57B1/6N female mice. JF-10-81 was found to block PC-3 cell attachment to various extracellular matrix components, mainly to vitronectin, the ligand of cell surface receptors integrin alphaVbeta3 and alphaVbeta5. Additionally, JF-10-81 reduced expression of integrins alphaVbeta3 and alphaVbeta5 on PC-3 cell surfaces, without effects on beta1 or any alphabeta1 heterodimers. This conjugate also inactivated phosphorylation of protein kinase B (PKB/Akt), down-regulated the expression of latent matrix metalloproteinase (MMP) -2 and MMP-9, but had little effect on MMP-3/-10. Meanwhile, membrane type-1 matrix metalloproteinase (MT1-MMP) and the tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) were not detectable in PC-3 cells. alphaVbeta3/alphaVbeta5 and MMP-2/-9 are known to be highly expressed in many tumor cells and play an important role in tumor progression. Our results support that this conjugate could possibly inhibit prostate cancer PC-3 cell invasion through a signaling pathway involving PI3K/Akt, alphaVbeta3/alphaVbeta5 and MMP-2/-9, and this SSA could be used as an efficient vector to deliver CPT or other cytotoxic agents to target sites for cancer therapy.
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Affiliation(s)
- Li-Chun Sun
- Peptide Research Laboratories, Department of Medicine, Tulane Health Sciences Center, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA.
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Palii SS, Caballero S, Shapiro G, Grant MB. Medical treatment of diabetic retinopathy with somatostatin analogues. Expert Opin Investig Drugs 2006; 16:73-82. [PMID: 17155855 DOI: 10.1517/13543784.16.1.73] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Traditional management strategies for retinal neovascularisation accompanying proliferative diabetic retinopathy include photocoagulation laser therapy. The development of preventative pharmacological treatments aimed at replacing or delaying this acute intervention has been an active research area and somatostatin analogues have shown promise in reducing the progression of retinal vascular pathologies. This review summarises the present knowledge on the molecular and cellular mechanisms of neovascularisation, and the rationale for the therapeutic use of somatostatin analogues as well as the results of two key recent clinical trials using octreotide. The potential use of octreotide and other somatostatin analogues in reducing the risk of severe visual impairment in proliferative diabetic retinopathy is discussed and pharmacological treatment regimens are proposed as an additional strategy or a less invasive alternative to laser therapy.
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Affiliation(s)
- Stela S Palii
- Pharmore, Inc., 5507 NW 80th Avenue, Gainesville, FL 32653, USA
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Watson SA, Grabowska AM, El-Zaatari M, Takhar A. Gastrin - active participant or bystander in gastric carcinogenesis? Nat Rev Cancer 2006; 6:936-46. [PMID: 17128210 DOI: 10.1038/nrc2014] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gastrin is a pro-proliferative, anti-apoptotic hormone with a central role in acid secretion in the gastric mucosa and a long-standing association with malignant progression in transgenic mouse models. However, its exact role in human gastric malignancy requires further validation. Gastrin expression is tightly regulated by two closely associated hormones, somatostatin and gastrin-releasing peptide, and aspects of their interaction may be deregulated during progression to gastric adenocarcinoma. Furthermore, agonists and antagonists of the receptors for all three hormones have shown modest clinical efficacy against gastric adenocarcinoma, which might provide useful information on the future combined use of these agents.
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Affiliation(s)
- Susan A Watson
- Academic Unit of Cancer Studies, University of Nottingham, Nottingham, NG7 2UH, UK.
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Abstract
BACKGROUND There is a need for novel antitumor agents that demonstrate efficacy in currently refractory tumors without adding to the toxicity of therapy. The somatostatin analogs, which have demonstrated antineoplastic activities in experimental tumor models, and good tolerability and safety profiles are attractive candidates. MATERIALS AND METHODS Data from preclinical studies provide evidence for direct and indirect mechanisms by which somatostatin analogs exert antitumor effects. RESULTS Direct antitumor activities, mediated through somatostatin receptors (sst(1)-sst(5)) expressed in tumor cells, include blockade of autocrine/paracrine growth-promoting hormone and growth factor production, inhibition of growth factor-mediated mitogenic signals and induction of apoptosis. Indirect antitumor effects include inhibition of growth-promoting hormone and growth factor secretion, and antiangiogenic actions. Many human tumors express more than one somatostatin receptor subtype, with sst(2) being predominant. Somatostatin analogs such as octreotide and lanreotide, which present a high affinity for sst(2), are in current clinical use to alleviate symptoms in patients with endocrine tumors, and radiolabeled somatostatin analogs have been developed for diagnosis and radiotherapy. CONCLUSIONS While the rationale exists for the use of somatostatin analogs as antitumor agents, studies are ongoing to identify analogs with activity across the range of receptor subtypes to maximize the potential of such treatment.
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Affiliation(s)
- C Susini
- INSERM U151, Institut Louis Bugnard, Toulouse, France.
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Liu Z, Schwimer J, Liu D, Lewis J, Greenway FL, York DA, Woltering EA. Gallic acid is partially responsible for the antiangiogenic activities ofRubus leaf extract. Phytother Res 2006; 20:806-13. [PMID: 16835875 DOI: 10.1002/ptr.1966] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An aqueous extract of leaves from Rubus suavissimus S. Lee (Rosaceae) or sweet leaf tea was tested for antiangiogenic activity in a human tissue-based fibrin-thrombin clot angiogenesis assay. Further fractionation of this crude extract was performed and the antiangiogenic effect of individual fractions was assessed. The extract was also tested for its oral bioavailability by using the serum of normal rats gavaged with the extract in the assay. At a 0.1% w/v concentration, the extract inhibited initiation of the angiogenic response and subsequent neovessel growth from samples that had already initiated an angiogenic response. Two subfractions of the extract showed significant inhibition of angiogenesis at 0.1% w/w. Gallic acid was elucidated as one of the active angiogenesis inhibitors in one fraction. A 1 mm concentration of gallic acid totally inhibited angiogenesis. In the form of leaf extract, a one-tenth concentration produced the same total inhibition as pure gallic acid. The 10-fold difference in potency suggests the presence of other active compounds contributing to the overall antiangiogenic effect of the extract. The oral absorption of this extract was tested by using serum from rats given the extract orally (gavage) in the angiogenesis assay system. The serum of rats orally administered the sweet leaf tea extract at doses of 0.1% w/w and 0.3% w/w did not significantly inhibit angiogenesis. However, the serum of rats injected intraperitoneally at a dose of 0.1% w/w caused a 41% inhibition of angiogenesis compared with saline injected controls. These preliminary results warrant further bioassay directed identification of other responsible compounds.
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Affiliation(s)
- Zhijun Liu
- School of Renewable Natural Resources, LSU Agricultural Center, Louisiana State University, Baton Rouge, LA 70803, USA.
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31
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Guillermet-Guibert J, Lahlou H, Pyronnet S, Bousquet C, Susini C. Endocrine tumours of the gastrointestinal tract. Somatostatin receptors as tools for diagnosis and therapy: molecular aspects. Best Pract Res Clin Gastroenterol 2005; 19:535-51. [PMID: 16183526 DOI: 10.1016/j.bpg.2005.03.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Somatostatin is a neuropeptide that acts as an endogenous inhibitor of various cellular functions including endocrine and exocrine secretions and the proliferation of normal and tumour cells. Its action is mediated by a family of G-protein-coupled receptors (sst1-sst5) that are widely distributed in normal and tumour cells. Gastroenteropancreatic endocrine tumours express multiple somatostatin receptors, sst2 being clearly predominant. These receptors represent the molecular basis for the clinical use of somatostatin analogues in the treatment of endocrine tumours and their in vivo localisation. This review covers current knowledge in somatostatin receptor biology and signalling.
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Liu Z, Schwimer J, Liu D, Greenway FL, Anthony CT, Woltering EA. Black raspberry extract and fractions contain angiogenesis inhibitors. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:3909-15. [PMID: 15884816 DOI: 10.1021/jf048585u] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Targeted therapies, such as agents that inhibit angiogenesis, offer hope as complementary agents in cancer therapy. Angiogenesis-inhibiting agents have the potential for inhibiting tumor growth and limiting the dissemination of metastasis, thus keeping cancers in a static growth state for prolonged periods. Black raspberry (Rubus occidentalis) extract was discovered to be antiangiogenic (0.1% w/v) in a novel human tissue-based in vitro fibrin clot angiogenesis assay. Assay-guided fractionation of a crude black raspberry extract resulted in a highly potent antiangiogenic fraction that accounted for only 1% of the fresh weight of whole black raspberries. At 0.075% (w/v), the active fraction completely inhibited angiogenic initiation and angiogenic vessel growth. Further subfractionation of this active fraction revealed the coexistence of multiple antiangiogenic compounds, one of which has been identified as gallic acid. However, the individual subfractions did not outperform the active whole fraction. These findings suggest that an active black raspberry fraction may be a promising complementary cancer therapy. It is natural and potent enough for manageable dosing regimens. These extracts contain multiple active ingredients that may be additive or synergistic in their antiangiogenic effects. These observations warrant further investigations in animals and human trials.
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Affiliation(s)
- Zhijun Liu
- Louisiana State University Agricultural Center, 227 Renewable Natural Resources Building, Baton Rouge, Louisiana 70803, USA
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Rivier JE, Kirby DA, Erchegyi J, Waser B, Eltschinger V, Cescato R, Reubi JC. Somatostatin receptor 1 selective analogues: 3. Dicyclic peptides. J Med Chem 2005; 48:515-22. [PMID: 15658865 DOI: 10.1021/jm049519m] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The binding affinity of short chain somatostatin (SRIF) analogues at the five human SRIF receptors (sst) was determined to identify sterically constrained somatostatin receptor subtype 1 (sst(1)) selective scaffolds. Des-AA(1,2,4,13)-[d-Trp(8)]SRIF (2) retained high binding affinity at all receptors but sst(1), Des-AA(1,2,4,5)-[d-Trp(8)]SRIF (3) at sst(4) and sst(5), and Des-AA(1,2,4,5,13)-[d-Trp(8)]SRIF (4) at sst(2) and sst(4) (AA = amino acid). Des-AA(1,2,4,12,13)-[d-Trp(8)]SRIF (6) was potent and sst(4)-selective (>25-fold); Des-AA(1,2,5,12,13)-[d-Trp(8)]SRIF (7) and Des-AA(1,2,4,5,12,13)-[d-Trp(8)]-SRIF (9, ODT-8) were most potent at sst(4) and moderately potent at all other receptors. Dicyclic SRIF agonists of the sst(1)-selective Des-AA(1,5)-[Tyr(2),d-Trp(8),IAmp(9)]SRIF, (14, sst(1) IC(50) = 14 nM) were prepared in which a lactam bridge introduced additional conformational constraint (IAmp = 4-(N-isopropyl)-aminomethylphenylalanine). Cyclo(7-12)Des-AA(1,5)-[Tyr(2),Glu(7),d-Trp(8),IAmp(9),hhLys(12)]SRIF (31) (sst(1) IC(50) = 16 nM) and cyclo(7-12) Des-AA(1,2,5)-[Glu(7),d-Trp(8),IAmp(9),m-I-Tyr(11),hhLys(12)]SRIF (45) (sst(1) IC(50) = 6.1 nM) had equal or improved affinities over that of the parent 14. Binding affinity was decreased in all other cases with alternate bridging constraints such as cyclo (6-11), cyclo (6-12), and cyclo (7-11). Compound 45 is an agonist (EC(50) = 8.8 nM) in the adenylate cyclase assay.
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Affiliation(s)
- Jean E Rivier
- The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, 10010 N. Torrey Pines Road, La Jolla, California 92037, USA.
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Zomerhuis MT, Hussain SM, Feelders RA, van der Lely AJ, de Herder WW. Octreotide exerts only acute, but no sustained, effects on MRI enhancement of liver metastases in carcinoid syndrome. Neuroendocrinology 2005; 82:41-8. [PMID: 16391492 DOI: 10.1159/000090636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Accepted: 10/18/2005] [Indexed: 11/19/2022]
Abstract
We have investigated the acute and sustained hemodynamic effects of octreotide on hepatic metastases of midgut carcinoids using contrast-enhanced dynamic magnetic resonance imaging (MRI). Seven patients with the carcinoid syndrome and metastasized midgut carcinoid tumors underwent functional dynamic multi-phase gadolinium-enhanced MRI of selected liver metastases at baseline and 60 min after the subcutaneous (s.c.) administration of 100 microg octreotide, and also after 3 months with three times daily (t.i.d.) 100 microg octreotide s.c. Baseline MRIs showed the typical aspect of carcinoid liver metastases with a very bright signal on the T2-weighted sequences and intense enhancement in the arterial phase after injection of gadolinium-diethylenetriaminepentaacetate. MRIs 60 min after the s.c. administration of 100 microg octreotide showed a 34.9 +/- 6.2% (mean +/- SD) reduction in relative enhancement in the selected liver metastases as compared to baseline. In 2 patients, however, there was no (significant) reduction in the relative enhancement in the selected liver metastases 60 min after the s.c. administration of 100 microg octreotide as compared to baseline. Only in 2 patients did the MRIs at 3 months show a decrease in relative enhancement in one of the selected liver metastases. At 3 months, with 100 microg octreotide s.c. t.i.d., there was no correlation between the change in relative enhancement on MRI and the change in 24-hour 5-HIAA excretion. There is thus only an acute effect of octreotide on the perfusion of liver metastases. This study further shows that contrast-enhanced dynamic MRI can be a very useful tool for studying hemodynamic effects of medical therapies on liver metastases in patients with metastatic midgut carcinoids.
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Affiliation(s)
- Menno T Zomerhuis
- Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
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Dasgupta P. Somatostatin analogues: multiple roles in cellular proliferation, neoplasia, and angiogenesis. Pharmacol Ther 2004; 102:61-85. [PMID: 15056499 DOI: 10.1016/j.pharmthera.2004.02.002] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Angiogenesis, the development of new blood vessels is a crucial process both for tumor growth and metastatic dissemination. Additionally, dysregulation in angiogenesis has been implicated in the pathogenesis of cardiovascular disease, proliferative retinopathy, diabetic nephropathy, and rheumatoid arthritis (RA). The neuropeptide somatostatin has been shown to be a powerful inhibitor of neovascularization in several experimental models. Furthermore, somatostatin receptors (sst) are expressed on endothelial cells; particularly, sst2 has been found to be uniquely up-regulated during the angiogenic switch, from quiescent to proliferative endothelium. The present manuscript reviews the anti-angiogenic activity of somatostatin and its analogues in neoplastic and nonneoplastic disease. The role of sst subtypes particularly sst2 in mediating its angioinhibitory activity is described. Somatostatin agonists may also exert their anti-angiogenic activity indirectly by inhibition of growth factors like vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and the growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis or through its immunomodulatory effects. However, the therapeutic utility of somatostatin agonists as anti-angiogenic drugs in these diseases remains confusing because of conflicting results from different studies. More basic research, as well as patient-oriented studies, is required to firmly establish the clinical potential of somatostatin agonists in therapeutic angiogenesis. The currently available somatostatin agonists have high affinity of sst2 with lower affinities for sst3 and sst5. The emergence of novel somatostatin agonists especially bispecific analogues (agonists targeting multiple cellular receptors) and conjugates (synthesized by chemically linking somatostatin analogues with other antineoplastic agents) with improved receptor specificity signify a new generation of anti-angiogenics, which may represent novel strategies in the treatment of neovascularization-related diseases.
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Affiliation(s)
- Piyali Dasgupta
- Department of Interdisciplinary Oncology, H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, Room 2068A, MRC-2 East, 12902 Magnolia Drive, Tampa, FL 33612, USA.
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36
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Abstract
Somatostatin is a peptide hormone that normally suppresses growth hormone (GH), thyrotropin (TSH), insulin and gut hormone release, as well as affecting multiple aspects of gastrointestinal function. It achieves these pleiotropic effects by binding somatostatin receptors (SSTR), a family of five G-protein coupled membrane receptors. Somatostatin analogs, such as octreotide, lanreotide and vapreotide, are well-established treatments for tumors that over secrete these hormones. Recently, use of somatostatin analogs for treating nonendocrine malignancies are being explored. Hu et al. found progressive reduction in SSTR3 expression when comparing normal gastric mucosa versus well differentiated versus poorly differentiated gastric adenocarcinomas; octreotide inhibited growth and induced apoptosis in vitro of those cells expressing SSTR3. Potential mechanisms by which somatostatin analogs may be useful in oncology include its endocrine actions, autocrine/paracrine effects, SSTR-mediated cell signaling and SSTR-mediated cell labeling.
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Affiliation(s)
- Adda Grimberg
- Division od Pediatric Endocrinology, The Children's Hospital of Philadelphia, Philadephia, PA 19104-4318, USA.
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