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Asymmetric Synthesis of US-FDA Approved Drugs over Five Years (2016–2020): A Recapitulation of Chirality. Pharmaceuticals (Basel) 2023; 16:ph16030339. [PMID: 36986439 PMCID: PMC10052577 DOI: 10.3390/ph16030339] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/09/2023] [Accepted: 02/17/2023] [Indexed: 02/25/2023] Open
Abstract
Chirality is a major theme in the design, discovery, and development of new drugs. Historically, pharmaceuticals have been synthesized as racemic mixtures. However, the enantiomeric forms of drug molecules have distinct biological properties. One enantiomer may be responsible for the desired therapeutic effect (eutomer), whereas the other may be inactive, interfere with the therapeutic form, or exhibit toxicity (distomer). Classical chemical synthesis usually leads to a racemic mixture unless stereospecific synthesis is employed. To meet the requirements of single-enantiomeric drugs, asymmetric synthesis has evolved at the forefront of drug discovery. Asymmetric synthesis involves the conversion of an achiral starting material into a chiral product. This review emphasizes the methods used for synthesizing FDA-approved chiral drugs during 2016–2020, with a special focus on asymmetric synthesis by means of chiral induction, resolution, or chiral pool.
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Zhang L, Lin Y, Xu X, Liu H, Wang X, Pan J. Telotristat Etiprate alleviates rheumatoid arthritis by targeting LGALS3 and affecting MAPK signaling. Intractable Rare Dis Res 2023; 12:45-57. [PMID: 36873667 PMCID: PMC9976094 DOI: 10.5582/irdr.2022.01121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/31/2023] [Accepted: 02/09/2023] [Indexed: 02/13/2023] Open
Abstract
Rheumatoid arthritis (RA) is one of the most widespread chronic immune-mediated inflammatory diseases characterized by continuous erosion of bone and cartilage by synovial hyperplasia. Telotristat Etiprate is an inhibitor of tryptophan hydroxylase, a rate-limiting enzyme in the biosynthesis of serotonin. Telotristat Etiprate can be used in the treatment of carcinoid syndrome. The purpose of this study was to explore the effect of Telotristat Etiprate on RA and its mechanism. We investigated Telotristat Etiprate in collagen-induced arthritis (CIA) model mice and in rheumatoid arthritis synovial fibroblasts (RASFs). Results showed that Telotristat Etiprate had anti-inflammatory effects both in vitro and in vivo, can inhibit the invasion and migration of cells, inhibit the formation of pannus, and induce cell apoptosis. Transcriptome sequencing (RNA-seq) and mass spectrometry analysis showed that Galectins-3 (LGALS3) could be a newly identified target of Telotristat Etiprate, affecting the phosphorylation of the MAPK signaling pathway through UBE2L6, thereby improving RA.
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Affiliation(s)
| | | | | | | | | | - Jihong Pan
- Address correspondence to:Jihong Pan, Biomedical Sciences College & Shandong Medicinal Biotechnology Centre, Shandong First Medical University & Shandong Academy of Medical Sciences, 6699 Qingdao Road, Ji'nan 250062, China. E-mail:
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Angelousi A, Koumarianou A, Chatzellis E, Kaltsas G. Resistance of neuroendocrine tumours to somatostatin analogs. Expert Rev Endocrinol Metab 2023; 18:33-52. [PMID: 36651768 DOI: 10.1080/17446651.2023.2166488] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 01/05/2023] [Indexed: 01/13/2023]
Abstract
INTRODUCTION A common feature shared by most neuroendocrine tumors (NETs) is the expression on their surface of somatostatin receptors (SSTRs) that are essential for their pathophysiological regulation, diagnosis, and management. The first-generation synthetic somatostatin analogs (SSAs), octreotide and lanreotide, constitute the cornerstone of treatment for growth hormone secreting pituitary adenomas and functioning, progressive functioning, and non-functioning gastro-entero-pancreatic (GEP-NETs). SSAs exert their mechanism of action through binding to the SSTRs; however, their therapeutic response is frequently attenuated or diminished by the development of resistance. The phenomenon of resistance is complex implicating the presence of additional epigenetic and genetic mechanisms. AREAS COVERED We aim to analyze the molecular, genetic, and epigenetic mechanisms of resistance to SSA treatment. We also summarize recent clinical data related to the development of resistance on conventional and non-conventional modes of administration of the first-generation SSAs and the second-generation SSA pasireotide. We explore mechanisms used to counteract the resistance to SSAs using higher doses or more frequent mode of administration of SSAs and/or combination treatments. EXPERT OPINION There is considerable heterogeneity in the development of resistance to SSAs that is tumor-specific necessitating the delineation of the underlying pathophysiological processes to further expand their therapeutic applications.
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Affiliation(s)
- Anna Angelousi
- First Department of Internal Medicine, Unit of Endocrinology, Laikon General hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Anna Koumarianou
- Hematology Oncology Unit, Fourth Department of Internal Medicine, Attikon University Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Eleftherios Chatzellis
- Endocrinology Diabetes and Metabolism Department, 251 Hellenic Air Force and VA General Hospital, Athens, Greece
| | - Gregory Kaltsas
- First Propaedeutic Department of Internal Medicine, Endocrine Unit, National and Kapodistrian University of Athens, Athens, Greece
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McClellan K, Chen EY, Kardosh A, Lopez CD, Del Rivero J, Mallak N, Rocha FG, Koethe Y, Pommier R, Mittra E, Pegna GJ. Therapy Resistant Gastroenteropancreatic Neuroendocrine Tumors. Cancers (Basel) 2022; 14:4769. [PMID: 36230691 PMCID: PMC9563314 DOI: 10.3390/cancers14194769] [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: 08/31/2022] [Revised: 09/24/2022] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a heterogenous group of malignancies originating from neuroendocrine cells of the gastrointestinal tract, the incidence of which has been increasing for several decades. While there has been significant progress in the development of therapeutic options for patients with advanced or metastatic disease, these remain limited both in quantity and durability of benefit. This review examines the latest research elucidating the mechanisms of both up-front resistance and the eventual development of resistance to the primary systemic therapeutic options including somatostatin analogues, peptide receptor radionuclide therapy with lutetium Lu 177 dotatate, everolimus, sunitinib, and temozolomide-based chemotherapy. Further, potential strategies for overcoming these mechanisms of resistance are reviewed in addition to a comprehensive review of ongoing and planned clinical trials addressing this important challenge.
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Affiliation(s)
- Kristen McClellan
- School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Emerson Y. Chen
- Division of Hematology Oncology, Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Adel Kardosh
- Division of Hematology Oncology, Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Charles D. Lopez
- Division of Hematology Oncology, Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Jaydira Del Rivero
- Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nadine Mallak
- Division of Molecular Imaging and Therapy, Oregon Health & Science University, Portland, OR 97239, USA
| | - Flavio G. Rocha
- Division of Surgical Oncology, Department of Surgery, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yilun Koethe
- Dotter Department of Interventional Radiology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Rodney Pommier
- Division of Surgical Oncology, Department of Surgery, Oregon Health & Science University, Portland, OR 97239, USA
| | - Erik Mittra
- Division of Molecular Imaging and Therapy, Oregon Health & Science University, Portland, OR 97239, USA
| | - Guillaume J. Pegna
- Division of Hematology Oncology, Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
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5
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Gu J, Wu Q, Zhang Q, You Q, Wang L. A decade of approved first-in-class small molecule orphan drugs: Achievements, challenges and perspectives. Eur J Med Chem 2022; 243:114742. [PMID: 36155354 DOI: 10.1016/j.ejmech.2022.114742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/01/2022] [Accepted: 09/01/2022] [Indexed: 12/01/2022]
Abstract
In the past decade (2011-2020), there was a growing interest in the discovery and development of orphan drugs for the treatment of rare diseases. However, rare diseases only account for a population of 0.65‰-1‰ which usually occur with previously unknown biological mechanisms and lack of specific therapeutics, thus to increase the demands for the first-in-class (FIC) drugs with new biological targets or mechanisms. Considering the achievements in the past 10 years, a total of 410 drugs were approved by U.S. Food and Drug Administration (FDA), which contained 151 FIC drugs and 184 orphan drugs, contributing to make up significant numbers of the approvals. Notably, more than 50% of FIC drugs are developed as orphan drugs and some of them have already been milestones in drug development. In this review, we aim to discuss the FIC small molecules for the development of orphan drugs case by case and highlight the R&D strategy with novel targets and scientific breakthroughs.
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Affiliation(s)
- Jinying Gu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Qiuyu Wu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Qiuyue Zhang
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Qidong You
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Lei Wang
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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Pagire SH, Pagire HS, Park KY, Bae EJ, Kim KE, Kim M, Yoon J, Parameswaran S, Choi JH, Park S, Jeon JH, Song JS, Bae MA, Lee IK, Kim H, Suh JM, Ahn JH. Identification of New Non-BBB Permeable Tryptophan Hydroxylase Inhibitors for Treating Obesity and Fatty Liver Disease. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27113417. [PMID: 35684355 PMCID: PMC9182086 DOI: 10.3390/molecules27113417] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022]
Abstract
Serotonin (5-hydroxytryptophan) is a hormone that regulates emotions in the central nervous system. However, serotonin in the peripheral system is associated with obesity and fatty liver disease. Because serotonin cannot cross the blood-brain barrier (BBB), we focused on identifying new tryptophan hydroxylase type I (TPH1) inhibitors that act only in peripheral tissues for treating obesity and fatty liver disease without affecting the central nervous system. Structural optimization inspired by para-chlorophenylalanine (pCPA) resulted in the identification of a series of oxyphenylalanine and heterocyclic phenylalanine derivatives as TPH1 inhibitors. Among these compounds, compound 18i with an IC50 value of 37 nM was the most active in vitro. Additionally, compound 18i showed good liver microsomal stability and did not significantly inhibit CYP and Herg. Furthermore, this TPH1 inhibitor was able to actively interact with the peripheral system without penetrating the BBB. Compound 18i and its prodrug reduced body weight gain in mammals and decreased in vivo fat accumulation.
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Affiliation(s)
- Suvarna H. Pagire
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
- JD Bioscience, 208 beon-gil, Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
| | - Haushabhau S. Pagire
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
- JD Bioscience, 208 beon-gil, Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
| | - Kun-Young Park
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (K.-Y.P.); (K.-e.K.); (H.K.)
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Eun Jung Bae
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
| | - Kwang-eun Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (K.-Y.P.); (K.-e.K.); (H.K.)
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Minhee Kim
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
| | - Jihyeon Yoon
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
| | - Saravanan Parameswaran
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
- Department of Biotechnology and Bioinformatics, School of Life Sciences, JSS Academy of Higher Education and Research (JSS AHER), Mysuru 570015, India
| | - Jun-Ho Choi
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
| | - Sungmi Park
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Korea; (S.P.); (J.-H.J.); (I.-K.L.)
| | - Jae-Han Jeon
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Korea; (S.P.); (J.-H.J.); (I.-K.L.)
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Chilgok Hospital, Daegu 41404, Korea
| | - Jin Sook Song
- Bio and Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34141, Korea; (J.S.S.); (M.A.B.)
| | - Myung Ae Bae
- Bio and Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34141, Korea; (J.S.S.); (M.A.B.)
| | - In-Kyu Lee
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Korea; (S.P.); (J.-H.J.); (I.-K.L.)
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu 41944, Korea
| | - Hail Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (K.-Y.P.); (K.-e.K.); (H.K.)
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Jae Myoung Suh
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea; (K.-Y.P.); (K.-e.K.); (H.K.)
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
- Correspondence: (J.M.S.); (J.H.A.)
| | - Jin Hee Ahn
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Korea; (S.H.P.); (H.S.P.); (E.J.B.); (M.K.); (J.Y.); (S.P.); (J.-H.C.)
- JD Bioscience, 208 beon-gil, Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Korea
- Correspondence: (J.M.S.); (J.H.A.)
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Mammoli A, Riccio A, Bianconi E, Coletti A, Camaioni E, Macchiarulo A. One Key and Multiple Locks: Substrate Binding in Structures of Tryptophan Dioxygenases and Hydroxylases. ChemMedChem 2021; 16:2732-2743. [PMID: 34137184 PMCID: PMC8518741 DOI: 10.1002/cmdc.202100312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 06/14/2021] [Indexed: 12/18/2022]
Abstract
Since its discovery at the beginning of the past century, the essential nutrient l-Tryptophan (l-Trp) and its catabolic pathways have acquired an increasing interest in an ever wider scientific community for their pivotal roles in underlying many important physiological functions and associated pathological conditions. As a consequence, enzymes catalyzing rate limiting steps along l-Trp catabolic pathways - including IDO1, TDO, TPH1 and TPH2 - have turned to be interesting drug targets for the design and development of novel therapeutic agents for different disorders such as carcinoid syndrome, cancer and autoimmune diseases. This article provides a fresh comparative overview on the most recent advancements that crystallographic studies, biophysical and computational works have brought on structural aspects and molecular recognition patterns of these enzymes toward l-Trp. Finally, a conformational analysis of l-Trp is also discussed as part of the molecular recognition process governing the binding of a substrate to its cognate enzymes.
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Affiliation(s)
- Andrea Mammoli
- Department of Pharmaceutical SciencesUniversity of PerugiaVia del Liceo N. 106123PerugiaItaly
| | - Alessandra Riccio
- Department of Pharmaceutical SciencesUniversity of PerugiaVia del Liceo N. 106123PerugiaItaly
| | - Elisa Bianconi
- Department of Pharmaceutical SciencesUniversity of PerugiaVia del Liceo N. 106123PerugiaItaly
| | - Alice Coletti
- Department of Medicine and SurgeryUniversity of PerugiaP. le Gambuli06132PerugiaItaly
| | - Emidio Camaioni
- Department of Pharmaceutical SciencesUniversity of PerugiaVia del Liceo N. 106123PerugiaItaly
| | - Antonio Macchiarulo
- Department of Pharmaceutical SciencesUniversity of PerugiaVia del Liceo N. 106123PerugiaItaly
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Wang L, Li R, Song C, Chen Y, Long H, Yang L. Small-Molecule Anti-Cancer Drugs From 2016 to 2020: Synthesis and Clinical Application. Nat Prod Commun 2021. [DOI: 10.1177/1934578x211040326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Malignant tumors have become a significant public health problem that severely threatens human health. Drug-targeting therapy is essential for tumor therapy, along with surgery and radiotherapy. Of the 378 novel drugs approved over the past five years, those for oncological therapy remains at the top (25%). These drugs are used to treat patients with various cancers by acting on corresponding targets, such as EGFR, JAK, BTK, IDH, and FLT3. This review examines anti-tumor agents approved between 2016 and 2020, classifying them according to indication (such as lung cancer, leukemia, breast cancer, and myeloma). These drugs are reviewed according to their route of administration, first-in-class designation, approval dates, and expedited review categories. Furthermore, this paper summarizes the targets and modes of action of the approved anti-tumor drugs while systematically discussing their synthetic routes for medicinal chemistry or industrial use, which will benefit next-generation drug discovery.
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Affiliation(s)
| | - Rong Li
- Xihua University, Chengdu, Sichuan, China
| | - Chen Song
- Xihua University, Chengdu, Sichuan, China
| | - Yanli Chen
- Xihua University, Chengdu, Sichuan, China
| | - Haiyue Long
- The Air Force Hospital of Western Theater command
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Fluorine-18-Labeled PET Radiotracers for Imaging Tryptophan Uptake and Metabolism: a Systematic Review. Mol Imaging Biol 2021; 22:805-819. [PMID: 31512038 DOI: 10.1007/s11307-019-01430-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Due to its metabolism via the serotonin and kynurenine pathways, tryptophan plays a key role in multiple disease processes including cancer. Imaging tryptophan uptake and metabolism in vivo can be achieved with tryptophan derivative positron emission tomography (PET) radiotracers. While human studies with such tracers have been confined to C-11-labeled compounds, preclinical development of F-18-labeled tryptophan-based radiotracers has surged in recent years. We performed a systematic review of studies reporting on such F-18-labeled tryptophan tracers to summarize and compare their biological characteristics and their potential for tumor imaging, with a particular focus on key enzymes of the kynurenine pathway (indoleamine 2,3-dioxygenase [IDO] and tryptophan 2,3-dioxygenase [TDO]), which play an important role in tumoral immune resistance. From a PubMed search, English language articles including data on the preparation and radiochemical and/or biological characteristics of F-18-labeled tryptophan derivative radiotracers were reviewed. A total of 19 original papers included data on 15 unique radiotracers, the majority of which were synthesized with an adequate radiochemical yield. Automated synthesis was reported for 1-(2-[18F]fluoroethyl)-L-tryptophan, the most extensively evaluated tracer thus far. Biodistribution studies showed high uptake in the pancreas, while the L-type amino acid transporter was the dominant transport mechanism for most of the reviewed tracers. Tracers tested for tumor uptake showed accumulation in tumor cell lines in vitro and in xenografts in vivo, often with favorable tumor-to-background uptake ratios in comparison with clinically used F-18-labeled radiotracers. Five tracers showed promise for imaging IDO activity, including 1-(2-[18F]fluoroethyl)-L-tryptophan and a F-18-labeled analog of alpha-[11C]methyl-L-tryptophan tested clinically in previous studies. Two radiotracers were metabolized by TDO but showed defluorination in vivo. In summary, most F-18-labeled tryptophan derivative PET tracers share common transport mechanisms and biodistribution characteristics. Several reported tracers could be candidates for further testing and validation toward PET imaging applications in a variety of human diseases.
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Bae EJ, Choi WG, Pagire HS, Pagire SH, Parameswaran S, Choi JH, Yoon J, Choi WI, Lee JH, Song JS, Bae MA, Kim M, Jeon JH, Lee IK, Kim H, Ahn JH. Peripheral Selective Oxadiazolylphenyl Alanine Derivatives as Tryptophan Hydroxylase 1 Inhibitors for Obesity and Fatty Liver Disease. J Med Chem 2021; 64:1037-1053. [PMID: 33417443 DOI: 10.1021/acs.jmedchem.0c01560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Tryptophan hydroxylase 1 (TPH1) has been recently suggested as a promising therapeutic target for treating obesity and fatty liver disease. A new series of 1,2,4-oxadiazolylphenyl alanine derivatives were identified as TPH1 inhibitors. Among them, compound 23a was the most active in vitro, with an IC50 (half-maximal inhibitory concentration) value of 42 nM, showed good liver microsomal stability, and showed no significant inhibition of CYP and hERG. Compound 23a inhibited TPH1 in the peripheral tissue with limited BBB penetration. In high-fat diet-fed mice, 23a reduced body weight gain, body fat, and hepatic lipid accumulation. Also, 23a improved glucose intolerance and energy expenditure. Taken together, compound 23a shows promise as a therapeutic agent for the treatment of obesity and fatty liver diseases.
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Affiliation(s)
- Eun Jung Bae
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Won Gun Choi
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Haushabhau S Pagire
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Suvarna H Pagire
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Saravanan Parameswaran
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Jun-Ho Choi
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Jihyeon Yoon
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Won-Il Choi
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Ji Hun Lee
- Bio and Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Jin Sook Song
- Bio and Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Myung Ae Bae
- Bio and Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Mijin Kim
- Research Institute of Aging and Metabolism, Kyungpook National University, Daegu 41404, Republic of Korea
| | - Jae-Han Jeon
- Research Institute of Aging and Metabolism, Kyungpook National University, Daegu 41404, Republic of Korea.,Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu 41944, Republic of Korea
| | - In-Kyu Lee
- Research Institute of Aging and Metabolism, Kyungpook National University, Daegu 41404, Republic of Korea.,Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu 41944, Republic of Korea
| | - Hail Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Jin Hee Ahn
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
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11
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Rayadurgam J, Sana S, Sasikumar M, Gu Q. Palladium catalyzed C–C and C–N bond forming reactions: an update on the synthesis of pharmaceuticals from 2015–2020. Org Chem Front 2021. [DOI: 10.1039/d0qo01146k] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Some of the most prominent and promising catalysts in organic synthesis for the requisite construction of C–C and C–N bonds are palladium (Pd) catalysts, which play a pivotal role in pharmaceutical and medicinal chemistry.
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Affiliation(s)
- Jayachandra Rayadurgam
- Research Center for Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-Sen University
- Guangzhou 510006
- People's Republic of China
| | - Sravani Sana
- Alder Research Chemicals Private Limited
- CSIR-IICT
- Hyderabad
- India
| | - M. Sasikumar
- Department of Chemistry
- Indian Institute of Science Education and Research
- Tirupati
- India
| | - Qiong Gu
- Research Center for Drug Discovery
- School of Pharmaceutical Sciences
- Sun Yat-Sen University
- Guangzhou 510006
- People's Republic of China
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12
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Maffei ME. 5-Hydroxytryptophan (5-HTP): Natural Occurrence, Analysis, Biosynthesis, Biotechnology, Physiology and Toxicology. Int J Mol Sci 2020; 22:E181. [PMID: 33375373 PMCID: PMC7796270 DOI: 10.3390/ijms22010181] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 01/20/2023] Open
Abstract
L-5-hydroxytryptophan (5-HTP) is both a drug and a natural component of some dietary supplements. 5-HTP is produced from tryptophan by tryptophan hydroxylase (TPH), which is present in two isoforms (TPH1 and TPH2). Decarboxylation of 5-HTP yields serotonin (5-hydroxytryptamine, 5-HT) that is further transformed to melatonin (N-acetyl-5-methoxytryptamine). 5-HTP plays a major role both in neurologic and metabolic diseases and its synthesis from tryptophan represents the limiting step in serotonin and melatonin biosynthesis. In this review, after an look at the main natural sources of 5-HTP, the chemical analysis and synthesis, biosynthesis and microbial production of 5-HTP by molecular engineering will be described. The physiological effects of 5-HTP are discussed in both animal studies and human clinical trials. The physiological role of 5-HTP in the treatment of depression, anxiety, panic, sleep disorders, obesity, myoclonus and serotonin syndrome are also discussed. 5-HTP toxicity and the occurrence of toxic impurities present in tryptophan and 5-HTP preparations are also discussed.
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Affiliation(s)
- Massimo E Maffei
- Department of Life Sciences and Systems Biology, University of Turin, Via Quarello 15/a, 10135 Turin, Italy
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13
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Betari N, Sahlholm K, Morató X, Godoy-Marín H, Jáuregui O, Teigen K, Ciruela F, Haavik J. Inhibition of Tryptophan Hydroxylases and Monoamine Oxidase-A by the Proton Pump Inhibitor, Omeprazole- In Vitro and In Vivo Investigations. Front Pharmacol 2020; 11:593416. [PMID: 33324221 PMCID: PMC7726444 DOI: 10.3389/fphar.2020.593416] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 10/16/2020] [Indexed: 01/06/2023] Open
Abstract
Serotonin (5-HT) is a hormone and neurotransmitter that modulates neural activity as well as a wide range of other physiological processes including cardiovascular function, bowel motility, and platelet aggregation. 5-HT synthesis is catalyzed by tryptophan hydroxylase (TPH) which exists as two distinct isoforms; TPH1 and TPH2, which are responsible for peripheral and central 5-HT, respectively. Due to the implication of 5-HT in a number of pathologies, including depression, anxiety, autism, sexual dysfunction, irritable bowel syndrome, inflammatory bowel disease, and carcinoid syndrome, there has been a growing interest in finding modulators of these enzymes in recent years. We thus performed high-throughput screening (HTS) using a fluorescence-based thermal shift assay (DSF) to search the Prestwick Chemical Library containing 1,280 compounds, mostly FDA-approved drugs, for TPH1 binders. We here report the identification of omeprazole, a proton pump inhibitor, as an inhibitor of TPH1 and TPH2 with low micromolar potency and high selectivity over the other aromatic amino acid hydroxylases. The S-enantiomer of omeprazole, esomeprazole, has recently also been described as an inhibitor of monoamine oxidase-A (MAO-A), the main enzyme responsible for 5-HT degradation, albeit with lower potency compared to the effect on TPH1 and TPH2. In order to investigate the net effect of simultaneous inhibition of TPH and MAO-A in vivo, we administered high-dose (100 mg/kg) omeprazole to CD-1 mice for 4 days, after which the animals were subjected to the tail suspension test. Finally, central (whole brain) and peripheral (serum) 5-HT content was measured using liquid chromatography-mass spectrometry (LC-MS). Omeprazole treatment significantly increased 5-HT concentrations, both in brain and in serum, and reduced the time spent immobile in the tail suspension test relative to vehicle control. Thus, the MAO-A inhibition afforded by high-dose omeprazole appears to overcome the opposing effect on 5-HT produced by inhibition of TPH1 and TPH2. Further modification of proton pump inhibitor scaffolds may yield more selective modulators of 5-HT metabolism.
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Affiliation(s)
- Nibal Betari
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Kristoffer Sahlholm
- Department of Integrative Medical Biology, Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Xavier Morató
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain.,Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Héctor Godoy-Marín
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Olga Jáuregui
- Scientific and Technological Centers of University of Barcelona (CCiTUB), Barcelona, Spain
| | - Knut Teigen
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Francisco Ciruela
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Jan Haavik
- Department of Biomedicine, University of Bergen, Bergen, Norway.,Division of Psychiatry, Bergen Center of Brain Plasticity, Haukeland University Hospital, Bergen, Norway
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14
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Discovery and biological characterization of a novel scaffold for potent inhibitors of peripheral serotonin synthesis. Future Med Chem 2020; 12:1461-1474. [DOI: 10.4155/fmc-2020-0127] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Aim: Tryptophan hydroxylase 1 (TPH1) catalyzes serotonin synthesis in peripheral tissues. Selective TPH1 inhibitors may be useful for treating disorders related to serotonin dysregulation. Results & methodology: Screening using a thermal shift assay for TPH1 binders yielded Compound 1 (2-(4-methylphenyl)-1,2-benzisothiazol-3(2 H)-one), which showed high potency (50% inhibition at 98 ± 30 nM) and selectivity for inhibiting TPH over related aromatic amino acid hydroxylases in enzyme activity assays. Structure–activity relationships studies revealed several analogs of 1 showing comparable potency. Kinetic studies suggested a noncompetitive mode of action of 1, with regards to tryptophan and tetrahydrobiopterin. Computational docking studies and live cell assays were also performed. Conclusion: This TPH1 inhibitor scaffold may be useful for developing new therapeutics for treating elevated peripheral serotonin.
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15
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Mei H, Han J, White S, Graham DJ, Izawa K, Sato T, Fustero S, Meanwell NA, Soloshonok VA. Tailor-Made Amino Acids and Fluorinated Motifs as Prominent Traits in Modern Pharmaceuticals. Chemistry 2020; 26:11349-11390. [PMID: 32359086 DOI: 10.1002/chem.202000617] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 04/23/2020] [Indexed: 12/11/2022]
Abstract
Structural analysis of modern pharmaceutical practices allows for the identification of two rapidly growing trends: the introduction of tailor-made amino acids and the exploitation of fluorinated motifs. Curiously, the former represents one of the most ubiquitous classes of naturally occurring compounds, whereas the latter is the most xenobiotic and comprised virtually entirely of man-made derivatives. Herein, 39 selected compounds, featuring both of these traits in the same molecule, are profiled. The total synthesis, source of the corresponding amino acids and fluorinated residues, and medicinal chemistry aspects and biological properties of the molecules are discussed.
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Affiliation(s)
- Haibo Mei
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, P.R. China
| | - Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, P.R. China
| | - Sarah White
- Oakwood Chemical, Inc., 730 Columbia Hwy. N, Estill, SC, 29918, USA
| | - Daniel J Graham
- Oakwood Chemical, Inc., 730 Columbia Hwy. N, Estill, SC, 29918, USA
| | - Kunisuke Izawa
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan
| | - Tatsunori Sato
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan
| | - Santos Fustero
- Departamento de Química Orgánica, Universidad de Valencia, 46100, Burjassot, Valencia, Spain
| | - Nicholas A Meanwell
- Department of Small Molecule Drug Discovery, Bristol-Myers Squibb Research and Development, P.O. Box 4000, Princeton, NJ, 08543-4000, USA
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, María Díaz de Haro 3, Plaza Bizkaia, 48013, Bilbao, Spain
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16
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Najjar A, Najjar A, Karaman R. Newly Developed Prodrugs and Prodrugs in Development; an Insight of the Recent Years. Molecules 2020; 25:E884. [PMID: 32079289 PMCID: PMC7070911 DOI: 10.3390/molecules25040884] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The design and development of prodrugs is the most common and effective strategy to overcome pharmacokinetic and pharmacodynamic drawbacks of active drugs. A respected number of prodrugs have been reached the drugs market throughout history and the recent years have witnessed a significant increase in the use of prodrugs as a replacement of their parent drugs for an efficient treatment of various ailment. METHODS A Scan conducted to find recent approved prodrugs and prodrugs in development. RESULTS Selected prodrugs were reported and categorized in accordance to their target systems. CONCLUSIONS the prodrug approach has shown many successes and still remains a viable and effective approach to deliver new active agents. This conclusion is supported by the recent approved prodrugs and the scan of clinical trials conducted between 2013-2018.
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Affiliation(s)
- Anas Najjar
- Faculty of Pharmacy, Department of Bioorganic & Pharmaceutical Chemistry, Al-Quds University, Jerusalem P.O. Box 20002, Palestine;
| | - Abderrahman Najjar
- Institute of Pathology, Rabin Medical Centre, PetachTikva 49100, Israel;
| | - Rafik Karaman
- Faculty of Pharmacy, Department of Bioorganic & Pharmaceutical Chemistry, Al-Quds University, Jerusalem P.O. Box 20002, Palestine;
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17
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Herrera-Martínez AD, Feelders RA, Van den Dungen R, Dogan-Oruc F, van Koetsveld PM, Castaño JP, de Herder WW, Hofland LJ. Effect of the Tryptophan Hydroxylase Inhibitor Telotristat on Growth and Serotonin Secretion in 2D and 3D Cultured Pancreatic Neuroendocrine Tumor Cells. Neuroendocrinology 2020; 110:351-363. [PMID: 31319410 DOI: 10.1159/000502200] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 07/16/2019] [Indexed: 12/14/2022]
Abstract
Serotonin, a biologically active amine, is related to carcinoid syndrome in functioning neuroendocrine tumors (NETs). Telotristat ethyl is a novel inhibitor of the tryptophan hydroxylase (TPH), a key enzyme in the production of serotonin. While its use in patients with carcinoid syndrome and uncontrolled diarrhea under somatostatin analogs (SSAs) has been recently approved, in vitro data evaluating its effectiveness are lacking. For this reason, we aimed to evaluate the effect of telotristat as monotherapy, and in combination with SSAs, on proliferation and secretion in a NET cell line model. The human pancreatic NET cell lines BON-1/QGP-1 were used as 2D and 3D cultured models; somatostatin receptor and TPH mRNA expression, as well as the potential autocrine effect of serotonin on tumor cell proliferation using a 3D culture system were evaluated. Telotristat decreased serotonin production in a dose-dependent manner at a clinically feasible concentration, without affecting cell proliferation. Its combination with pasireotide, but not with octreotide, had an additive inhibitory effect on serotonin secretion. The effect of telotristat was slightly less potent, when BON-1 cells were co-treated with octreotide. Octreotide and pasireotide had no effect on the expression of TPH. Telotristat did not have an effect on mRNA expression of somatostatin receptor subtypes. Finally, we showed that serotonin did not have an autocrine effect on NET cell proliferation on the 3D cell model. These results suggest that telotristat is an effective drug for serotonin inhibition, but the effectiveness of its combination with SST2 (somatostatin receptor subtype 2)-preferring SSA should be evaluated in more detail.
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Affiliation(s)
- Aura D Herrera-Martínez
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands,
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain,
| | - Richard A Feelders
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Rosanna Van den Dungen
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Fadime Dogan-Oruc
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Peter M van Koetsveld
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Justo P Castaño
- Maimonides Institute for Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain
| | - Wouter W de Herder
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Leo J Hofland
- Division of Endocrinology, Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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18
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Abstract
The rate-limiting enzyme in serotonin synthesis is tryptophan hydroxylase (TPH). There are two independent serotonin systems in the body characterized by two isoforms of TPH, TPH1 and TPH2. While TPH2 synthesizes serotonin in the brain, TPH1 is expressed in the gut and in other peripheral tissues and supplies platelets in the circulation with serotonin. This duality of the serotonin system is enforced by the blood-brain barrier which is impermeable for serotonin. In the brain serotonin acts as neurotransmitter and is a main target for the treatment of psychiatric disorders. In the periphery it is released by platelets at the site of activation and elicits numerous physiological effects. TPH1 deficient mice were shown to be protected from diverse diseases including hemostatic, inflammatory, fibrotic, gastrointestinal, and metabolic disorders and therefore serotonin synthesis inhibition emerged as a reasonable therapeutic paradigm. Recently the first TPH inhibitor, telotristat ethyl, came on the market for the treatment of carcinoid syndrome. This review summarizes the state of development and the therapeutic opportunities of such compounds.
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Affiliation(s)
- Michael Bader
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Str. 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany; Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site, Berlin, Germany.
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19
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Saavedra C, Barriuso J, McNamara MG, Valle JW, Lamarca A. Spotlight on telotristat ethyl for the treatment of carcinoid syndrome diarrhea: patient selection and reported outcomes. Cancer Manag Res 2019; 11:7537-7556. [PMID: 31496810 PMCID: PMC6690650 DOI: 10.2147/cmar.s181439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/21/2019] [Indexed: 12/12/2022] Open
Abstract
Neuroendocrine tumors (NETs) are rare cancers with an associated prolonged survival in some patients. A proportion of patients diagnosed with NETs will present with carcinoid syndrome symptoms, characterized by diarrhea, flushing and/or wheezing. This review summarizes the current treatment options for carcinoid syndrome, focusing on the latest novel treatment option, telotristat ethyl. In addition, information on patient-reported outcomes and impact of carcinoid syndrome on quality of life (QOL) and improvement of following treatment with telotristat ethyl are reviewed. This article also provides an overview of the current QOL questionnaires for patients with NETs and addresses unmet needs in this field of patient-reported outcomes.
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Affiliation(s)
- Cristina Saavedra
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Medical Oncology Department, Ramon Y Cajal University Hospital, Madrid, Spain
| | - Jorge Barriuso
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Mairéad G McNamara
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Juan W Valle
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
| | - Angela Lamarca
- Medical Oncology Department, The Christie NHS Foundation Trust, Manchester, UK.,Division of Cancer Sciences, University of Manchester, Manchester, UK
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20
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Yabut JM, Crane JD, Green AE, Keating DJ, Khan WI, Steinberg GR. Emerging Roles for Serotonin in Regulating Metabolism: New Implications for an Ancient Molecule. Endocr Rev 2019; 40:1092-1107. [PMID: 30901029 PMCID: PMC6624793 DOI: 10.1210/er.2018-00283] [Citation(s) in RCA: 206] [Impact Index Per Article: 41.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 03/18/2019] [Indexed: 12/12/2022]
Abstract
Serotonin is a phylogenetically ancient biogenic amine that has played an integral role in maintaining energy homeostasis for billions of years. In mammals, serotonin produced within the central nervous system regulates behavior, suppresses appetite, and promotes energy expenditure by increasing sympathetic drive to brown adipose tissue. In addition to these central circuits, emerging evidence also suggests an important role for peripheral serotonin as a factor that enhances nutrient absorption and storage. Specifically, glucose and fatty acids stimulate the release of serotonin from the duodenum, promoting gut peristalsis and nutrient absorption. Serotonin also enters the bloodstream and interacts with multiple organs, priming the body for energy storage by promoting insulin secretion and de novo lipogenesis in the liver and white adipose tissue, while reducing lipolysis and the metabolic activity of brown and beige adipose tissue. Collectively, peripheral serotonin acts as an endocrine factor to promote the efficient storage of energy by upregulating lipid anabolism. Pharmacological inhibition of serotonin synthesis or signaling in key metabolic tissues are potential drug targets for obesity, type 2 diabetes, and nonalcoholic fatty liver disease (NAFLD).
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Affiliation(s)
- Julian M Yabut
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.,Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
| | - Justin D Crane
- Department of Biology, Northeastern University, Boston, Massachusetts
| | - Alexander E Green
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.,Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada
| | - Damien J Keating
- College of Medicine and Public Health, Flinders University, Bedford Park, South Australia, Australia
| | - Waliul I Khan
- Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada.,Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Gregory R Steinberg
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.,Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada.,Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
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21
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Langbein T, Dathe W, Deuerling A, Baum RP. Efficacy of Detoxsan ® powder on diarrhea caused by gastrointestinal neuroendocrine tumors. World J Gastroenterol 2019; 25:2133-2143. [PMID: 31114139 PMCID: PMC6506581 DOI: 10.3748/wjg.v25.i17.2133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 03/27/2019] [Accepted: 03/30/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Patients with neuroendocrine tumors (NETs) of the gastrointestinal tract suffer frequently from chronic diarrhea. A well characterized medical advice containing zeolite (Detoxsan® powder) was applied to patients suffered from therapy-refractory diarrhea either by its frequency or by watery stool, despite receiving standard pharmacotherapy according to the guidelines for carcinoid syndrome and comorbidities. Detoxsan® powder acts as an adsorbent and might reduce significantly symptoms of diarrhea in patients suffering from NETs.
AIM To overcome the therapy-refractory diarrhea of patients with NETs by the zeolite containing medical advice Detoxsan® powder.
METHODS A total of 20 patients (12 female and 8 male) suffering from diarrhea either by its frequency or from watery stool caused by NETs were included. In each patient, the diagnosis had been confirmed by histology and somatostatin receptors expression proven by positron emission tomography/computed tomography using Ga-68-labeled somatostatin analogs. All patients received standard-of-care pharmacotherapy and were additionally given Detoxsan® powder as an extemporaneous drug containing 90% natural Cuban zeolite and 10% magnesium aspartate. Recommended daily dosage ranges between 3 g once to three times per day. Each day dose and bowel movements were documented by the patients themselves in a pre-defined table. Additionally to the bowel movements quantitative determinations of serotonin, urea, creatinine and single ions were performed within the serum of the patients by commercially available equipment used as a matter of routine in the clinic.
RESULTS All patients enrolled in this pilot study did not only suffer from NETs, but also from comorbidities and treatment-resistant diarrhea. There was insufficient control of diarrhea, most probably due to the secretion of hormones like serotonin produced by the slowly growing and highly differentiated NETs. All patients only took Detoxsan® powder as an antidiarrheal drug. In general, response effects need several days to become perceptible and require an intake of Detoxsan® powder for an extended time period or intermittently, if persisting stabilization of bowel movements could not be achieved. A correlation between NET grade, part and size of bowel resection and functionality of the tumor could not be demonstrated. Therefore, diarrhea seemed to be based on the metabolic activity of the well-differentiated NETs, which eventually led to treatment resistance. In summary, 14 out of the 20 patients (70%) declared to be very content with using Detoxsan® powder and observed a significant reduction of diarrhea, while the effective dose and intake period that resulted in a symptom relief varied individually.
CONCLUSION Detoxsan® powder is able to reduce significantly symptoms of NET-related diarrhea in the majority of patients. The duration of taking Detoxsan® powder and its dosage vary individually.
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Affiliation(s)
- Thomas Langbein
- Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Zentralklinik Bad Berka, Bad Berka D-99437, Germany
| | - Wilfried Dathe
- Scientific Managment, Heck Bio-Pharma GmbH, Winterbach D-73650, Germany
| | - Anika Deuerling
- Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Zentralklinik Bad Berka, Bad Berka D-99437, Germany
| | - Richard P Baum
- Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Zentralklinik Bad Berka, Bad Berka D-99437, Germany
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22
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Flick AC, Leverett CA, Ding HX, McInturff E, Fink SJ, Helal CJ, O’Donnell CJ. Synthetic Approaches to the New Drugs Approved During 2017. J Med Chem 2019; 62:7340-7382. [DOI: 10.1021/acs.jmedchem.9b00196] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Andrew C. Flick
- Seattle Genetics, Inc. 21823 30th Drive SE, Bothell, Washington 98021, United States
| | - Carolyn A. Leverett
- Groton Laboratories, Pfizer Worldwide Research and Development, 445 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Hong X. Ding
- Pharmacodia (Beijing) Co., Ltd., Beijing, 100085, China
| | - Emma McInturff
- Groton Laboratories, Pfizer Worldwide Research and Development, 445 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Sarah J. Fink
- BioDuro, 11011 Torreyana Road, San Diego, California 92121, United States
| | - Christopher J. Helal
- Groton Laboratories, Pfizer Worldwide Research and Development, 445 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Christopher J. O’Donnell
- Groton Laboratories, Pfizer Worldwide Research and Development, 445 Eastern Point Road, Groton, Connecticut 06340, United States
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23
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Rendell MS. The journey from gene knockout to clinical medicine: telotristat and sotagliflozin. DRUG DESIGN DEVELOPMENT AND THERAPY 2019; 13:817-824. [PMID: 30880915 PMCID: PMC6408923 DOI: 10.2147/dddt.s144556] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Gene knockout has been a powerful technique to evaluate the physiologic role of selected gene products. Lexicon pioneered high-throughput gene knockout technology and went further in designing agents to inhibit products of gene expression. Two agents have entered late-stage development. Telotristat is an inhibitor of tryptophan hydroxylase (TPH), preventing the production of serotonin. Although this agent blocks the two isoforms of TPH, it does not cross the blood–brain barrier, thus avoiding central neurologic manifestations. It inhibits the peripheral production of serotonin, and in particular prevents serotonin action in the intestines, resulting in decreased peristaltic action. Lexicon successfully developed telotristat to treat carcinoid syndrome not responding adequately to somatostatin inhibitors. Sotagliflozin development proceeded from the observation that dual inhibition of SGLT2 in the kidneys and SGLT1 in the intestines resulted in increased renal glucose excretion, reduced early-phase glucose absorption, as well as increased blood levels of GLP-1 and PYY. Initial development efforts focused on type 1 diabetes and have shown reduced postprandial glucose levels, less tendency to hypoglycemia, and lower HbA1c. Several other SGLT2 inhibitors have been associated with increased frequency of diabetic ketoacidosis (DKA). In the type 1 trials, sotagliflozin-treated individuals experienced DKA at a higher rate than placebo-treated patients. The sotagliflozin development program has now been extended to trials on type 2 diabetes. Long-term clinical trials will determine the benefits and risks of the agent in comparison to other currently marketed SGLT2 inhibitors.
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Affiliation(s)
- Marc S Rendell
- Association of Diabetes Investigators, Omaha, NE 68131, USA, .,Rose Salter Medical Research Foundation, Newport Coast, CA 92657, USA,
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Weaver SR, Fricke HP, Xie C, Aiello RJ, Charles JF, Hernandez LL. Peripartum dietary supplementation of a small-molecule inhibitor of tryptophan hydroxylase 1 compromises infant, but not maternal, bone. Am J Physiol Endocrinol Metab 2018; 315:E1133-E1142. [PMID: 30351987 PMCID: PMC6336963 DOI: 10.1152/ajpendo.00198.2018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/28/2018] [Accepted: 10/19/2018] [Indexed: 12/20/2022]
Abstract
Long-term effects of breastfeeding on maternal bone are not fully understood. Excessive maternal bone loss stimulated by serotonin signaling during lactation may increase bone fragility later in life. We hypothesized that inhibiting nonneuronal serotonin activity by feeding a small-molecule inhibitor of the rate-limiting enzyme in serotonin synthesis [tryptophan hydroxylase 1 (TPH1)] would preserve maternal bone postweaning without affecting neonatal bone. Chow supplemented with the small-molecule TPH1 inhibitor LP778902 (~100 mg/kg) or control chow was fed to C57BL/6 dams throughout pregnancy and lactation, and blood was collected on days 1 and 21 of lactation. Dams returned to a common diet postweaning and were aged to 3 or 9 mo postweaning. Pups were euthanized at weaning. The effect of TPH1 inhibition on dam and pup femoral bone was determined by micro-computed tomography. Peripartum dietary supplementation with LP778902 decreased maternal serum serotonin concentrations ( P = 0.0007) and reduced bone turnover, indicated by serum NH2-terminal propeptide of type I collagen ( P = 0.01) and COOH-terminal collagen cross-links ( P = 0.02) concentrations, on day 21 of lactation. Repressed bone turnover from TPH1 inhibition was not associated with structural changes in maternal femur at 3 or 9 mo postweaning. By contrast, neonates exposed to peripartum LP778902 demonstrated differences in trabecular and cortical femoral bone compared with pups from control dams, with fewer ( P = 0.02) and thinner ( P = 0.001) trabeculae as well as increased trabecular spacing ( P = 0.04). Additionally, cortical porosity was increased ( P = 0.007) and cortical tissue mineral density was decreased ( P = 0.005) in pups of LP778902-treated dams. Small-molecule TPH1 inhibitors should be carefully considered in pregnant and lactating women, given potential risks to neonatal bone development.
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Affiliation(s)
- Samantha R Weaver
- Endocrinology and Reproductive Physiology Program, University of Wisconsin-Madison , Madison, Wisconsin
| | - Hannah P Fricke
- Department of Dairy Science, University of Wisconsin-Madison , Madison, Wisconsin
| | - Cynthia Xie
- Departments of Orthopedics and Medicine, Brigham and Women's Hospital , Boston, Massachusetts
| | | | - Julia F Charles
- Departments of Orthopedics and Medicine, Brigham and Women's Hospital , Boston, Massachusetts
| | - Laura L Hernandez
- Endocrinology and Reproductive Physiology Program, University of Wisconsin-Madison , Madison, Wisconsin
- Department of Dairy Science, University of Wisconsin-Madison , Madison, Wisconsin
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Jin XF, Spampatti MP, Spitzweg C, Auernhammer CJ. Supportive therapy in gastroenteropancreatic neuroendocrine tumors: Often forgotten but important. Rev Endocr Metab Disord 2018; 19:145-158. [PMID: 29464446 DOI: 10.1007/s11154-018-9443-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Neuroendocrine tumors (NETs) are a group of rare and heterogeneous malignancies that can develop in various organs. A significant number of gastroenteropancreatic neuroendocrine tumours (GEP-NETs) is functionally active and presents with symptoms related to the secretion of biologically active substances, leading to the development of distinct clinical syndromes. There are various therapeutic approaches for GEP-NETs, including curative surgery, palliative surgery, local-ablative and loco-regional therapies as well as systemic therapeutic options including peptide receptor radionuclide therapy, cytotoxic therapy, and molecularly targeted therapies. Specific supportive therapy of patients with NETs includes management or prevention of hormone-related clinical syndromes and paraneoplastic states. Supportive therapy plays a key role in NET treatment. Supportive therapy includes debulking surgery and interventional radiologic techniques to reduce tumour bulk or load, as well as systemic medical treatment options to manage or prevent hypersecretion syndromes and treatment-related side effects. Supportive therapies are a type of of comprehensive treatment addressing the patient as a whole person throughout the process of NET treatment. Therefore, supportive therapy also encompasses psychosocial support, expert nursing, nutritional support and management of cancer related pain.
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Affiliation(s)
- Xi-Feng Jin
- Department of Internal Medicine IV, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Matilde P Spampatti
- Department of Internal Medicine II, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany
- Interdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM), Klinikum der Universitaet Muenchen, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Marchioninistr, 15, 81377, Munich, Germany
| | - Christine Spitzweg
- Department of Internal Medicine IV, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany
- Interdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM), Klinikum der Universitaet Muenchen, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Marchioninistr, 15, 81377, Munich, Germany
| | - Christoph J Auernhammer
- Department of Internal Medicine IV, University-Hospital Campus Grosshadern, Ludwig-Maximilian University of Munich, Munich, Germany.
- Interdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM), Klinikum der Universitaet Muenchen, Ludwig-Maximilians-University of Munich, Campus Grosshadern, Marchioninistr, 15, 81377, Munich, Germany.
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Matthes S, Bader M. Peripheral Serotonin Synthesis as a New Drug Target. Trends Pharmacol Sci 2018; 39:560-572. [PMID: 29628275 DOI: 10.1016/j.tips.2018.03.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 12/19/2022]
Abstract
The first step in serotonin (5-HT) biosynthesis is catalyzed by tryptophan hydroxylase (TPH). There are two independent sources of the monoamine that have distinct functions: first, the TPH1-expressing enterochromaffin cells (ECs) of the gut; second, TPH2-expressing serotonergic neurons. TPH1-deficient mice revealed that peripheral 5-HT plays important roles in platelet function and in inflammatory and fibrotic diseases of gut, pancreas, lung, and liver. Therefore, TPH inhibitors were developed which cannot pass the blood-brain barrier to specifically block peripheral 5-HT synthesis. They showed therapeutic efficacy in several rodent disease models, and telotristat ethyl is the first TPH inhibitor to be approved for the treatment of carcinoid syndrome. We review this development and discuss further therapeutic options for these compounds.
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Affiliation(s)
- Susann Matthes
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Michael Bader
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany; Berlin Institute of Health (BIH), Anna-Louisa-Karsch-Straße 2, 10178 Berlin, Germany; Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany.
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Cuyle PJ, Prenen H. Practical management of toxicities associated with targeted therapies for advanced gastroenteropancreatic neuroendocrine tumors. Ann Gastroenterol 2018; 31:140-150. [PMID: 29507461 PMCID: PMC5825944 DOI: 10.20524/aog.2018.0224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Accepted: 11/13/2017] [Indexed: 02/06/2023] Open
Abstract
Neuroendocrine tumors are heterogeneous, rare malignancies that arise most frequently in the gastroenteropancreatic tract (GEPNET). The therapeutic armamentarium for the treatment of GEPNETs has expanded significantly over the last two decades, however the ideal sequencing strategy remains controversial. As this disease may be relatively slow-growing, patients are expected to be treated for longer periods, so that even mild toxicities can influence quality of life, compliance and outcome in the long run. Prospective data on optimal adverse event management are lacking and recommendations are largely based on expert opinion and drug prescribing information. This review summarizes practical recommendations for toxicity management associated with the most commonly used GEPNET treatment options and stresses important focus points for future clinical trials.
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Affiliation(s)
- Pieter-Jan Cuyle
- Department of Gastroenterology/Digestive Oncology, Imelda General Hospital, Bonheiden (Pieter-Jan Cuyle), Belgium
| | - Hans Prenen
- Department of Gastroenterology/Digestive Oncology, University Hospitals Gasthuisberg Leuven, Leuven (Hans Prenen), Belgium
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Abstract
PURPOSE OF REVIEW To review recent advances and controversies in all aspects of carcinoid-syndrome. RECENT FINDINGS Over the last few years there have been a number of advances in all aspects of carcinoid syndrome as well as new therapies. These include new studies on its epidemiology which demonstrate it is increasing in frequency; increasing insights into the pathogenesis of its various clinical manifestations and into its natural history: definition of prognostic factors; new methods to verify its presence; the development of new drugs to treat its various manifestations, both initially and in somatostatin-refractory cases; and an increased understanding of the pathogenesis, natural history and management of carcinoid heart disease. These advances have generated several controversies and these are also reviewed. SUMMARY There have been numerous advances in all aspects of the carcinoid-syndrome, which is the most common functional syndrome neuroendocrine tumors produce. These advances are leading to new approaches to the management of these patients and in some cases to new controversies.
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Affiliation(s)
- Tetsuhide Ito
- Neuroendocrine Tumor Centre, Fukuoka Sanno Hospital, International University of Health and Welfare
| | - Lingaku Lee
- Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Digestive Diseases Branch, NIDDK, NIH, Bethesda, Maryland, USA
| | - Robert T Jensen
- Digestive Diseases Branch, NIDDK, NIH, Bethesda, Maryland, USA
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