1
|
Periferakis A, Tsigas G, Periferakis AT, Tone CM, Hemes DA, Periferakis K, Troumpata L, Badarau IA, Scheau C, Caruntu A, Savulescu-Fiedler I, Caruntu C, Scheau AE. Agonists, Antagonists and Receptors of Somatostatin: Pathophysiological and Therapeutical Implications in Neoplasias. Curr Issues Mol Biol 2024; 46:9721-9759. [PMID: 39329930 PMCID: PMC11430067 DOI: 10.3390/cimb46090578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Revised: 08/29/2024] [Accepted: 08/31/2024] [Indexed: 09/28/2024] Open
Abstract
Somatostatin is a peptide that plays a variety of roles such as neurotransmitter and endocrine regulator; its actions as a cell regulator in various tissues of the human body are represented mainly by inhibitory effects, and it shows potent activity despite its physiological low concentrations. Somatostatin binds to specific receptors, called somatostatin receptors (SSTRs), which have different tissue distributions and associated signaling pathways. The expression of SSTRs can be altered in various conditions, including tumors; therefore, they can be used as biomarkers for cancer cell susceptibility to certain pharmacological agents and can provide prognostic information regarding disease evolution. Moreover, based on the affinity of somatostatin analogs for the different types of SSTRs, the therapeutic range includes conditions such as tumors, acromegaly, post-prandial hypotension, hyperinsulinism, and many more. On the other hand, a number of somatostatin antagonists may prove useful in certain medical settings, based on their differential affinity for SSTRs. The aim of this review is to present in detail the principal characteristics of all five SSTRs and to provide an overview of the associated therapeutic potential in neoplasias.
Collapse
Affiliation(s)
- Argyrios Periferakis
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Elkyda, Research & Education Centre of Charismatheia, 17675 Athens, Greece
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
| | - Georgios Tsigas
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Aristodemos-Theodoros Periferakis
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Elkyda, Research & Education Centre of Charismatheia, 17675 Athens, Greece
| | - Carla Mihaela Tone
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Daria Alexandra Hemes
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Konstantinos Periferakis
- Akadimia of Ancient Greek and Traditional Chinese Medicine, 16675 Athens, Greece
- Pan-Hellenic Organization of Educational Programs, 17236 Athens, Greece
| | - Lamprini Troumpata
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Ioana Anca Badarau
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Cristian Scheau
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Radiology and Medical Imaging, "Foisor" Clinical Hospital of Orthopaedics, Traumatology and Osteoarticular TB, 030167 Bucharest, Romania
| | - Ana Caruntu
- Department of Oral and Maxillofacial Surgery, The "Carol Davila" Central Military Emergency Hospital, 010825 Bucharest, Romania
- Department of Oral and Maxillofacial Surgery, Faculty of Dental Medicine, "Titu Maiorescu" University, 031593 Bucharest, Romania
| | - Ilinca Savulescu-Fiedler
- Department of Internal Medicine, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Internal Medicine and Cardiology, Coltea Clinical Hospital, 030167 Bucharest, Romania
| | - Constantin Caruntu
- Department of Physiology, The "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Dermatology, "Prof. N.C. Paulescu" National Institute of Diabetes, Nutrition and Metabolic Diseases, 011233 Bucharest, Romania
| | - Andreea-Elena Scheau
- Department of Radiology and Medical Imaging, Fundeni Clinical Institute, 022328 Bucharest, Romania
| |
Collapse
|
2
|
Oron-Herman M, Kirmayer D, Lupp A, Schulz S, Kostenich G, Afargan M. Expression prevalence and dynamics of GPCR somatostatin receptors 2 and 3 as cancer biomarkers beyond NET: a paired immunohistochemistry approach. Sci Rep 2023; 13:20857. [PMID: 38012197 PMCID: PMC10682014 DOI: 10.1038/s41598-023-47877-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 11/16/2023] [Indexed: 11/29/2023] Open
Abstract
Somatostatin receptors are clinically validated GPCR biomarkers for diagnosis and treatment of various neuroendocrine tumors (NET). Among the five somatostatin receptors, SST2 and SST3 are associated with apoptosis and cell cycle arrest, making these receptor subtypes better differentiated targets in precision oncology. In this study we performed immunohistochemistry of paired tissue microarrays containing 1125 cores, representing 43 tumor types, each stained for SST2 and SST3. A 12-point immunoreactive scoring (IRS) range was used for interpretation of the staining results. We analyzed the results twice, using the conventional positivity IRS cutoffs ≥ 3 and more stringent ≥ 6. Evaluation of receptors expression dynamics was performed for tumor-nodes-metastases (TNM) defined subgroups (ovarian and hepatocellular adenocarcinomas) as a function of their tumor stage. Our results indicate that two-thirds of tested cores exhibit clinically significant expression of at least SST2 or SST3 (IRS ≥ 6). The expression prevalence of both receptors tends to decline with tumor progression. However, an unexpected upregulation of both SST2 and SST3 reemerged in metastases suggesting conserved receptors genetic potential during tumor life cycle. We suggest that SST2 and SST3 should be further explored as potential biomarkers and therapeutic tools for maximizing the efficiency of somatostatin-based precision oncology of solid tumors beyond NET.
Collapse
Affiliation(s)
- Mor Oron-Herman
- Starget Pharma, 26 Snir st., 4704086, Ramat Hasharon, Israel.
| | - David Kirmayer
- Starget Pharma, 26 Snir st., 4704086, Ramat Hasharon, Israel
| | - Amelie Lupp
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, Drackendorfer Str. 1, 07747, Jena, Germany
| | - Stefan Schulz
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, Drackendorfer Str. 1, 07747, Jena, Germany
| | - Genady Kostenich
- Starget Pharma, 26 Snir st., 4704086, Ramat Hasharon, Israel
- The Advanced Technology Center, Sheba Medical Center, Tel Hashomer, 5262000, Ramat Gan, Israel
| | - Michel Afargan
- Starget Pharma, 26 Snir st., 4704086, Ramat Hasharon, Israel
| |
Collapse
|
3
|
Abstract
Acromegaly is a systemic disease associated with increased morbidity and mortality that can be prevented with adequate disease control. Three modalities of treatment (surgery, medical treatment, and radiotherapy) are available; however, a significant proportion of patients still maintain disease activity despite treatment. Therefore, there is a need for innovations in the treatment of acromegaly that include changes in the current trial and error approach and the development of new drugs. In this review, we summarize the recent innovations in the treatment of acromegaly and address the future perspectives in this field.
Collapse
Affiliation(s)
- Leandro Kasuki
- Neuroendocrinology Research Center/Endocrinology Division, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil; Neuroendocrinology Division, Instituto Estadual Do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil; Endocrinology Division, Hospital Federal de Bonsucesso, Rio de Janeiro, Brazil
| | - Mônica R Gadelha
- Neuroendocrinology Research Center/Endocrinology Division, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil; Neuroendocrinology Division, Instituto Estadual Do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil; Neuropathology and Molecular Genetics Laboratory, Instituto Estadual Do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil.
| |
Collapse
|
4
|
Current and Emerging Medical Therapies in Pituitary Tumors. J Clin Med 2022; 11:jcm11040955. [PMID: 35207228 PMCID: PMC8877616 DOI: 10.3390/jcm11040955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/01/2022] [Accepted: 02/10/2022] [Indexed: 12/04/2022] Open
Abstract
Pituitary tumors (PT) represent in, the majority of cases, benign tumors for which surgical treatment still remains, except for prolactin-secreting PT, the first-line therapeutic option. Nonetheless, the role played by medical therapies for the management of such tumors, before or after surgery, has evolved considerably, due in part to the recent development of well-tolerated and highly efficient molecules. In this review, our aim was to present a state-of-the-art of the current medical therapies used in the field of PT and the benefits and caveats for each of them, and further specify their positioning in the therapeutic algorithm of each phenotype. Finally, we discuss the future of PT medical therapies, based on the most recent studies published in this field.
Collapse
|
5
|
Gadelha MR, Wildemberg LE, Kasuki L. The Future of Somatostatin Receptor Ligands in Acromegaly. J Clin Endocrinol Metab 2022; 107:297-308. [PMID: 34618894 PMCID: PMC8764337 DOI: 10.1210/clinem/dgab726] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Indexed: 12/13/2022]
Abstract
Currently, the first-generation somatostatin receptor ligands (fg-SRLs), octreotide LAR and lanreotide autogel, are the mainstays of acromegaly treatment and achieve biochemical control in approximately 40% of patients and tumor shrinkage in over 60% of patients. Pasireotide, a second-generation SRL, shows higher efficacy with respect to both biochemical control and tumor shrinkage but has a worse safety profile. In this review, we discuss the future perspectives of currently available SRLs, focusing on the use of biomarkers of response and precision medicine, new formulations of these SRLs and new drugs, which are under development. Precision medicine, which is based on biomarkers of response to treatment, will help guide the decision-making process by allowing physicians to choose the appropriate drug for each patient and improving response rates. New formulations of available SRLs, such as oral, subcutaneous depot, and nasal octreotide, may improve patients' adherence to treatment and quality of life since there will be more options available that better suit each patient. Finally, new drugs, such as paltusotine, somatropin, ONO-5788, and ONO-ST-468, may improve treatment adherence and present higher efficacy than currently available drugs.
Collapse
Affiliation(s)
- Monica R Gadelha
- Endocrine Unit and Neuroendocrinology Research Center, Medical School and Hospital Universitário Clementino Fraga Filho - Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-913, Brazil
- Neuroendocrine Unit - Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, 20231-092, Brazil
- Neuropathology and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, 20231-092, Brazil
- Correspondence: Mônica R. Gadelha, Rua Prof. Rodolpho Paulo Rocco, 255, 9th floor, Ilha do Fundão, Rio de Janeiro 21941-913, Brazil.
| | - Luiz Eduardo Wildemberg
- Endocrine Unit and Neuroendocrinology Research Center, Medical School and Hospital Universitário Clementino Fraga Filho - Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-913, Brazil
- Neuroendocrine Unit - Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, 20231-092, Brazil
| | - Leandro Kasuki
- Endocrine Unit and Neuroendocrinology Research Center, Medical School and Hospital Universitário Clementino Fraga Filho - Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21941-913, Brazil
- Neuroendocrine Unit - Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, 20231-092, Brazil
| |
Collapse
|
6
|
Pharmacological Characterization of Veldoreotide as a Somatostatin Receptor 4 Agonist. Life (Basel) 2021; 11:life11101075. [PMID: 34685446 PMCID: PMC8541358 DOI: 10.3390/life11101075] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 10/01/2021] [Accepted: 10/07/2021] [Indexed: 12/12/2022] Open
Abstract
Veldoreotide, a somatostatin analogue, binds to the somatostatin receptors (SSTR) 2, 4, and 5. The current aim was to assess its pharmacological activity as an SSTR4 agonist. G-protein signaling was assessed using a fluorescence-based membrane potential assay in human embryonic kidney 293 (HEK293) cells stably co-expressing G-protein-coupled inwardly rectifying potassium 2 channels and the individual SSTR2, SSTR4, and SSTR5, and in human BON-1 cells stably expressing these SSTRs. Veldoreotide effects on chromogranin A (CgA) secretion and cell proliferation were examined in BON-1 cells. In HEK293 transfected cells, veldoreotide showed a high efficacy for activating the SSTR4; octreotide and pasireotide had little activity (Emax, 99.5% vs. 27.4% and 52.0%, respectively). Veldoreotide also activated SSTR2 and SSTR5 (Emax, 98.4% and 96.9%, respectively). In BON-1 cells, veldoreotide activated SSTR2, SSTR4, and SSTR5 with high potency and efficacy. CgA secretion was decreased to a greater degree in the BON-1 cells expressing SSTR4 versus the cells expressing SSTR2 and SSTR5 (65.3% vs. 80.3% and 77.6%, respectively). In the BON-1 cells expressing SSTR4, veldoreotide inhibited cell proliferation more than somatostatin SS-14 (71.2% vs. 79.7%) and to a similar extent as the SSTR4 agonist J-2156 in the presence of SSTR2 and SSTR5 antagonists. Veldoreotide is a full agonist of SSTR2, SSTR4, and SSTR5.
Collapse
|
7
|
Antunes X, Kasuki L, Gadelha MR. New and emerging pharmacological treatment options for acromegaly. Expert Opin Pharmacother 2021; 22:1615-1623. [PMID: 33783289 DOI: 10.1080/14656566.2021.1908998] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Introduction: Transsphenoidal surgery is the first-line treatment for acromegaly, but even in referral centers, approximately 50% of patients are not cured, and adjuvant pharmacological treatment is necessary. Widely used therapies encompass different drug classes, such as injectable somatostatin receptor ligands (SRLs), oral dopamine agonists and injectable growth hormone receptor antagonists, but approximately 40% of patients still have disease activity in real-life practice. Therefore, there is a need for new medical therapies to allow disease control in a larger proportion of patients, increase quality of life, reduce morbidity and mortality and improve treatment adherence in acromegaly.Areas covered: In this review, the authors cover new and emerging drugs under development or drugs recently approved for the treatment of acromegaly.Expert opinion: Disease control is essential to reduce morbidity and mortality in acromegaly but is still not achieved in a significant proportion of patients or takes a long time to be achieved with currently available options and treatment algorithms. Therefore, the development of new drugs as well as the establishment of biomarkers of disease control to allow precision medicine will improve treatment and outcomes in acromegaly.
Collapse
Affiliation(s)
- Ximene Antunes
- Neuroendocrinology Research Center/Endocrinology Division, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leandro Kasuki
- Neuroendocrinology Research Center/Endocrinology Division, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Neuroendocrinology Division, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil.,Endocrinology Division, Hospital Federal de Bonsucesso, Rio de Janeiro, Brazil
| | - Mônica R Gadelha
- Neuroendocrinology Research Center/Endocrinology Division, Medical School and Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Neuroendocrinology Division, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil.,Neuropatology and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde, Rio de Janeiro, Brazil
| |
Collapse
|
8
|
Somatostatin-Dopamine Chimeric Molecules in Neuroendocrine Neoplasms. J Clin Med 2021; 10:jcm10030501. [PMID: 33535394 PMCID: PMC7867079 DOI: 10.3390/jcm10030501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 12/12/2022] Open
Abstract
Neuroendocrine neoplasms (NENs) are a widely heterogeneous family of neoplasms arising from neuroendocrine cells, which are interspersed throughout the body. Despite NENs are relatively rare, their incidence and prevalence are constantly increasing probably due to the improvement in earlier diagnosis and patients’ management. When surgery is not curative, particularly for patients with metastatic disease, several medical options are available. Somatostatin analogues (SSA) are the first-line medical therapy for well-differentiated NENs. Interestingly, the heterodimerization of somatostatin receptors (SSTs) with dopamine receptors (DRs) has been discovered in NENs. This phenomenon results in hybrid receptors with enhanced functional activity. On these bases, chimeric molecules embracing somatostatin and dopamine features have been recently developed. The aim of this review is to provide a comprehensive overview of the available preclinical and clinical data regarding chimeric somatostatin-dopamine agonists as a new class of “magic bullet” in the therapy of NENs.
Collapse
|
9
|
Störmann S, Schopohl J. Drug treatment strategies for secondary diabetes in patients with acromegaly. Expert Opin Pharmacother 2020; 21:1883-1895. [PMID: 32633582 DOI: 10.1080/14656566.2020.1789098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Acromegaly is a rare disease due to oversecretion of growth hormone (GH). Even though the disease is often portrayed by its most apparent clinical features, given the abundance of GH receptors throughout the body, it truly is a systemic disease leading to numerous complications and comorbidities. A distinct medical issue in the context of acromegaly is diabetes: It can be a complication as a consequence of GH excess and its mediators, but it can also result from treatment of acromegaly. AREAS COVERED This review provides an overview of the effects of acromegaly pathophysiology on glucose homeostasis. Furthermore, it devotes an extensive section on the influence that acromegaly treatment has on glucose metabolism, including approved as well as currently investigated drugs. It also summarizes observations from the use of anti-diabetic medication in patients with acromegaly. EXPERT OPINION Glucose imbalance is an important aspect of acromegaly comorbidity and deserves more attention. Even though numerous studies have investigated glucose homeostasis in acromegaly, there is still a clear need for more basic, translational, and also clinical research to advance the understanding of the underlying mechanisms and how to best address them.
Collapse
Affiliation(s)
- Sylvère Störmann
- Klinikum der Universität München, Medizinische Klinik und Poliklinik IV , München, Germany
| | - Jochen Schopohl
- Klinikum der Universität München, Medizinische Klinik und Poliklinik IV , München, Germany
| |
Collapse
|
10
|
Solari D, Pivonello R, Caggiano C, Guadagno E, Chiaramonte C, Miccoli G, Cavallo LM, Del Basso De Caro M, Colao A, Cappabianca P. Pituitary Adenomas: What Are the Key Features? What Are the Current Treatments? Where Is the Future Taking Us? World Neurosurg 2020; 127:695-709. [PMID: 31266132 DOI: 10.1016/j.wneu.2019.03.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 03/05/2019] [Indexed: 12/18/2022]
Abstract
Pituitary tumors are a heterogeneous group of lesions (usually benign) and proper understanding of the anatomy, physiology, and pathology of the hypothalamic/pituitary region is essential to make an accurate diagnosis and define the essential treatment options (i.e., surgery, medical therapies, and radiotherapy, alone or in combination). Surgery is the primary treatment for acromegaly, Cushing disease, thyroid-stimulating hormone-secreting adenomas, resistant prolactinomas, and nonfunctioning pituitary adenomas causing mass effect. Medical and radiation therapy are reserved in cases in which surgery is not possible or does not provide a complete cure. In the last decades, tremendous innovations (i.e., targeted drugs and refined surgical tools and techniques) have expanded the treatment strategies for pituitary adenomas. We herein report the current indications for and depiction of the surgical techniques in pituitary surgery, review current medical treatments, and provide a glimpse of future possibilities.
Collapse
Affiliation(s)
- Domenico Solari
- Division of Neurosurgery, Università degli Studi di Napoli "Federico II", Naples, Italy.
| | - Rosario Pivonello
- Division of Endocrinology, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Chiara Caggiano
- Division of Neurosurgery, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Elia Guadagno
- Department of Advanced Biomedical Sciences, Section of Pathology, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Carmela Chiaramonte
- Division of Neurosurgery, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Giovanni Miccoli
- Division of Neurosurgery, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Luigi M Cavallo
- Division of Neurosurgery, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Marialaura Del Basso De Caro
- Department of Advanced Biomedical Sciences, Section of Pathology, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Annamaria Colao
- Division of Endocrinology, Università degli Studi di Napoli "Federico II", Naples, Italy
| | - Paolo Cappabianca
- Division of Neurosurgery, Università degli Studi di Napoli "Federico II", Naples, Italy
| |
Collapse
|
11
|
Abstract
Snake and spider venoms have been developed by nature as a defense mechanism against predators or to immobilize their prey by blocking the cardiovascular, respiratory, and/or nervous systems. Consequently, predators are deterred from approaching their prey by painful sensations. At a molecular level, the targeted physiological systems are blocked or stimulated by peptide toxins which, once injected into the body, modulate, though not exclusively, important cell membrane ion channels and receptors. Millions of years of constant evolution have led to the evolvement of complex venom libraries of optimized protein toxins, making them more potent, more selective, resistant to proteases, less immunogenic, and improved in terms of pharmacokinetic (PK) properties. The resulting advantage is that they induce long-term and potent pharmacodynamic (PD) effects toward unique molecular targets of therapeutic importance such as coagulation cascade proteins, receptors, and ionic channels. This optimization process has been enabled by the diversification of peptide sequences (mainly by gene duplication) and an upscaling of the complexity of toxin peptide scaffold structures, through implementation of multiple disulfide bridges and sequence-active motif diversification, leading to a wide diversity of chemical structures. This combination of pharmaceutical properties has made venom toxins valuable both as pharmacological tools and as leads for drug development. These highly tunable molecules can be tailored to achieve desirable biocompatibility and biodegradability with simultaneously selective and potent therapeutic effects. This brief overview provides basic definitions, rules, and methodologies and describes successful examples of a few drugs developed from snake toxins that are currently used in the clinic for therapy of several diseases as well as new molecular entities in clinical development based on spider-venom-derived peptide toxins.
Collapse
|
12
|
Gadelha MR, Kasuki L, Lim DST, Fleseriu M. Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update. Endocr Rev 2019; 40:268-332. [PMID: 30184064 DOI: 10.1210/er.2018-00115] [Citation(s) in RCA: 197] [Impact Index Per Article: 39.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 07/26/2018] [Indexed: 12/19/2022]
Abstract
Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.
Collapse
Affiliation(s)
- Mônica R Gadelha
- Neuroendocrinology Research Center/Endocrine Section and Medical School, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Neuroendocrine Section, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde do Rio de Janeiro, Rio de Janeiro, Brazil.,Neuropathology and Molecular Genetics Laboratory, Instituto Estadual do Cérebro Paulo Niemeyer, Rio de Janeiro, Brazil
| | - Leandro Kasuki
- Neuroendocrinology Research Center/Endocrine Section and Medical School, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Neuroendocrine Section, Instituto Estadual do Cérebro Paulo Niemeyer, Secretaria Estadual de Saúde do Rio de Janeiro, Rio de Janeiro, Brazil.,Endocrine Unit, Hospital Federal de Bonsucesso, Rio de Janeiro, Brazil
| | - Dawn S T Lim
- Department of Endocrinology, Singapore General Hospital, Singapore, Singapore
| | - Maria Fleseriu
- Department of Endocrinology, Diabetes and Metabolism, Oregon Health and Science University, Portland, Oregon.,Department of Neurological Surgery, Oregon Health and Science University, Portland, Oregon.,Northwest Pituitary Center, Oregon Health and Science University, Portland, Oregon
| |
Collapse
|
13
|
Paragliola RM, Salvatori R. Novel Somatostatin Receptor Ligands Therapies for Acromegaly. Front Endocrinol (Lausanne) 2018; 9:78. [PMID: 29563895 PMCID: PMC5845985 DOI: 10.3389/fendo.2018.00078] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 02/20/2018] [Indexed: 12/21/2022] Open
Abstract
Surgery is considered the treatment of choice in acromegaly, but patients with persistent disease after surgery or in whom surgery cannot be considered require medical therapy. Somatostatin receptor ligands (SRLs) octreotide (OCT), lanreotide, and the more recently approved pasireotide, characterized by a broader receptor ligand binding profile, are considered the mainstay in the medical management of acromegaly. However, in the attempt to offer a more efficacious and better tolerated medical approach, recent research has been aimed to override some limitations related to the use of currently approved drugs and novel SRLs therapies, with potential attractive features, have been proposed. These include both new formulation of older molecules and new molecules. Novel OCT formulations are aimed in particular to improve patients' compliance and to reduce injection discomfort. They include an investigational ready-to-use subcutaneous depot OCT formulation (CAM2029), delivered via prefilled syringes and oral OCT that uses a "transient permeability enhancer" technology, which allows for OCT oral absorption. Another new delivery system is a long-lasting OCT implant (VP-003), which provide stable doses of OCT throughout a period of several months. Finally, a new SRL DG3173 (somatoprim) seems to be more selective for GH secretion, suggesting possible advantages in the presence of hyperglycemia or diabetes. How much these innovations will actually be beneficial to acromegaly patients in real clinical practice remains to be seen.
Collapse
Affiliation(s)
| | - Roberto Salvatori
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, Pituitary Center Johns Hopkins University School of Medicine, Baltimore, MD, United States
- *Correspondence: Roberto Salvatori,
| |
Collapse
|
14
|
Zupančič O, Bernkop-Schnürch A. Lipophilic peptide character – What oral barriers fear the most. J Control Release 2017; 255:242-257. [DOI: 10.1016/j.jconrel.2017.04.038] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 04/21/2017] [Accepted: 04/25/2017] [Indexed: 10/19/2022]
|
15
|
Maffezzoni F, Frara S, Doga M, Mazziotti G, Giustina A. New medical therapies of acromegaly. Growth Horm IGF Res 2016; 30-31:58-63. [PMID: 27745780 DOI: 10.1016/j.ghir.2016.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 09/26/2016] [Accepted: 10/02/2016] [Indexed: 12/29/2022]
Abstract
Acromegaly is a rare disease associated with significant morbidity and increased mortality. Treatment of acromegaly aims at controlling growth hormone hypersecretion, improving patients' symptoms and comorbidities and normalizing mortality. The therapeutic options for acromegaly include surgery, medical therapies and radiotherapy. However, despite all these treatment options, approximately one-half of patients are not adequately controlled. Progress in molecular research has made possible to develop new therapeutic strategies to improve control of acromegaly. This article will review the new medical approaches to acromegaly which consist in evolution of traditional therapeutic protocols and development of new molecules with different profiles of activity.
Collapse
Affiliation(s)
| | - S Frara
- Endocrinology, University of Brescia, Italy
| | - M Doga
- Endocrinology, University of Brescia, Italy
| | - G Mazziotti
- Endocrinology, University of Brescia, Italy; Endocrinology, ASST Carlo Poma of Mantua, Italy
| | - A Giustina
- Endocrinology, University of Brescia, Italy.
| |
Collapse
|
16
|
Schilbach K, Schopohl J. Update on the use of oral octreotide therapy for acromegaly. Expert Rev Endocrinol Metab 2016; 11:349-355. [PMID: 30058923 DOI: 10.1080/17446651.2016.1199954] [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] [Indexed: 10/21/2022]
Abstract
Somatostatin analogs are most commonly used in pharmacological treatment of acromegaly. Pegvisomant and dopamine agonists are alternatives, which are used to a lesser extent. Dopamine agonists are the only orally applicable medication but are less effective than the other options. For a large number of patients, life-long pharmacotherapy has to be applied and frequent injections represent a reduction of quality of life for many of them. Areas covered: Recently published evidence for the use of oral octreotide therapy for acromegaly. Expert commentary: Oral octreotide is a novel and effective treatment for acromegaly and the side effects have been shown to be comparable to the injectable SSAs. The combination with a transient permeability enhancer allows intestinal permeation but also enables molecules with a size <70 kDa to pass transiently. This does not seem to have an acute or subacute consequence, but the long-term effect is still elusive. Therefore, more long-term trials are desirable.
Collapse
Affiliation(s)
- Katharina Schilbach
- a Medizinische Klinik und Poliklinik IV , Klinikum der Universität München , Munich , Germany
| | - Jochen Schopohl
- a Medizinische Klinik und Poliklinik IV , Klinikum der Universität München , Munich , Germany
| |
Collapse
|
17
|
Maffezzoni F, Formenti AM, Mazziotti G, Frara S, Giustina A. Current and future medical treatments for patients with acromegaly. Expert Opin Pharmacother 2016; 17:1631-42. [PMID: 27352098 DOI: 10.1080/14656566.2016.1199687] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Acromegaly is a relatively rare condition of growth hormone (GH) excess associated with significant morbidity and, when left untreated, high mortality. Therapy for acromegaly is targeted at decreasing GH and insulin-like growth hormone 1 levels, ameliorating patients' symptoms and decreasing any local compressive effects of the pituitary adenoma. The therapeutic options for acromegaly include surgery, medical therapies (such as dopamine agonists, somatostatin receptor ligands and the GH receptor antagonist pegvisomant) and radiotherapy. However, despite all these treatments option, approximately 50% of patients are not adequately controlled. AREAS COVERED In this paper, the authors discuss: 1) efficacy and safety of current medical therapy 2) the efficacy and safety of the new multireceptor-targeted somatostatin ligand pasireotide 3) medical treatments currently under clinical investigation (oral octreotide, ITF2984, ATL1103), and 4) preliminary data on the use of new injectable and transdermal/transmucosal formulations of octreotide. EXPERT OPINION This expert opinion supports the need for new therapeutic agents and modalities for patients with acromegaly.
Collapse
Affiliation(s)
| | | | | | - Stefano Frara
- a Chair of Endocrinology , University of Brescia , Brescia , Italy
| | - Andrea Giustina
- a Chair of Endocrinology , University of Brescia , Brescia , Italy
| |
Collapse
|
18
|
Schneider EL, Henise J, Reid R, Ashley GW, Santi DV. Subcutaneously Administered Self-Cleaving Hydrogel–Octreotide Conjugates Provide Very Long-Acting Octreotide. Bioconjug Chem 2016; 27:1638-44. [DOI: 10.1021/acs.bioconjchem.6b00188] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eric L. Schneider
- ProLynx, 455 Mission Bay Boulevard South,
Suite 145, San Francisco, California 94158, United States
| | - Jeff Henise
- ProLynx, 455 Mission Bay Boulevard South,
Suite 145, San Francisco, California 94158, United States
| | - Ralph Reid
- ProLynx, 455 Mission Bay Boulevard South,
Suite 145, San Francisco, California 94158, United States
| | - Gary W. Ashley
- ProLynx, 455 Mission Bay Boulevard South,
Suite 145, San Francisco, California 94158, United States
| | - Daniel V. Santi
- ProLynx, 455 Mission Bay Boulevard South,
Suite 145, San Francisco, California 94158, United States
- Department
of Pharmaceutical Chemistry, University of California, San Francisco, 600 16th Street, San Francisco, California 94158, United States
| |
Collapse
|
19
|
Günther T, Culler M, Schulz S. Research Resource: Real-Time Analysis of Somatostatin and Dopamine Receptor Signaling in Pituitary Cells Using a Fluorescence-Based Membrane Potential Assay. Mol Endocrinol 2016; 30:479-90. [PMID: 26967369 DOI: 10.1210/me.2015-1241] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Stable somatostatin analogues and dopamine receptor agonists are the mainstay for the pharmacological treatment of functional pituitary adenomas; however, only a few cellular assays have been developed to detect receptor activation of novel compounds without disrupting cells to obtain the second messenger content. Here, we adapted a novel fluorescence-based membrane potential assay to characterize receptor signaling in a time-dependent manner. This minimally invasive technique provides a robust and reliable read-out for ligand-induced receptor activation in permanent and primary pituitary cells. The mouse corticotropic cell line AtT-20 endogenously expresses both the somatostatin receptors 2 (sst2) and 5 (sst5). Exposure of wild-type AtT-20 cells to the sst2- and sst5-selective agonists BIM-23120 and BIM-23268, respectively, promoted a pertussis toxin- and tertiapin-Q-sensitive reduction in fluorescent signal intensity, which is indicative of activation of G protein-coupled inwardly rectifying potassium (GIRK) channels. After heterologous expression, sst1, sst3, and sst4 receptors also coupled to GIRK channels in AtT-20 cells. Similar activation of GIRK channels by dopamine required overexpression of dopamine D2 receptors (D2Rs). Interestingly, the presence of D2Rs in AtT-20 cells strongly facilitated GIRK channel activation elicited by the sst2-D2 chimeric ligand BIM-23A760, suggesting a synergistic action of sst2 and D2Rs. Furthermore, stable somatostatin analogues produced strong responses in primary pituitary cultures from wild-type mice; however, in cultures from sst2 receptor-deficient mice, only pasireotide and somatoprim, but not octreotide, induced a reduction in fluorescent signal intensity, suggesting that octreotide mediates its pharmacological action primarily via the sst2 receptor.
Collapse
Affiliation(s)
- Thomas Günther
- Department of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, D-07749 Jena, Germany
| | - Michael Culler
- Department of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, D-07749 Jena, Germany
| | - Stefan Schulz
- Department of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University Jena, D-07749 Jena, Germany
| |
Collapse
|
20
|
Abstract
The currently available somatostatin receptor ligands (SRLs) and growth hormone (GH) antagonists are used to control levels of GH and insulin-like growth factor 1 (IGF-1) in patients with acromegaly. However, these therapies are limited by wide variations in efficacy, associated adverse effects and the need for frequent injections. A phase III trial of oral octreotide capsules demonstrated that this treatment can safely sustain suppressed levels of GH and IGF-1 and reduce the severity of symptoms in patients with acromegaly previously controlled by injectable SRL therapy, with the added benefit of no injection-site reactions. Phase I and phase II trials of the pan-selective SRL DG3173, the liquid crystal octreotide depot CAM2029 and an antisense oligonucleotide directed against the GH receptor have shown that these agents can be used to achieve biochemical suppression in acromegaly and have favourable safety profiles. This Review outlines the need for new therapeutic agents for patients with acromegaly, reviews clinical trial data of investigational agents and considers how these therapies might best be integrated into clinical practice.
Collapse
Affiliation(s)
- Shlomo Melmed
- Pituitary Center, Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Room 2015, Los Angeles, California 90048, USA
| |
Collapse
|
21
|
van Adrichem RCS, de Herder WW, Kamp K, Brugts MP, de Krijger RR, Sprij-Mooij DM, Lamberts SWJ, van Koetsveld PM, Janssen JAMJL, Hofland LJ. Effects of Somatostatin Analogs and Dopamine Agonists on Insulin-Like Growth Factor 2-Induced Insulin Receptor Isoform A Activation by Gastroenteropancreatic Neuroendocrine Tumor Cells. Neuroendocrinology 2016; 103:815-25. [PMID: 26836610 DOI: 10.1159/000444280] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 01/17/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) express insulin-like growth factor (IGF)-related factors [IGF1, IGF2; insulin receptor (IR)-A, IR-B; IGF-binding protein (IGFBP) 1-3] as well as somatostatin (SSTRs) and dopamine D2 receptors (D2Rs). OBJECTIVES To (1) compare mRNA expression of IGF-related factors in human pancreatic NET (panNET) cell lines with that in human GEP-NETs to evaluate the usefulness of these cells as a model for studying the IGF system in GEP-NETs, (2) determine whether panNET cells produce growth factors that activate IR-A, and (3) investigate whether somatostatin analogs (SSAs) and/or dopamine agonists (DAs) influence the production of these growth factors. METHODS In panNET cells (BON-1 and QGP-1) and GEP-NETs, mRNA expression of IGF-related factors was measured by quantitative real-time PCR. Effects of the SSAs octreotide and pasireotide (PAS), the DA cabergoline (CAB), and the dopastatin BIM-23A760 (all 100 nM) were evaluated at the IGF2 mRNA and protein level (by ELISA) and regarding IR-A bioactivity (by kinase receptor activation assay) in panNET cells. RESULTS panNET cells and GEP-NETs had comparable expression profiles of IGF-related factors. Especially in BON-1 cells, IGF2 and IR-A were most highly expressed. PAS + CAB inhibited IGF2 (-29.5 ± 4.9%, p < 0.01) and IGFBP3 (-20.0 ± 4.0%, p < 0.01) mRNA expression in BON-1 cells. In BON-1 cells, IGF2 protein secretion was significantly inhibited with BIM-23A760 (-23.7 ± 3.8%). BON-1- but not QGP-1- conditioned medium stimulated IR-A bioactivity. In BON-1 cells, IR-A bioactivity was inhibited by BIM-23A760 and PAS + CAB (-37.8 ± 2.1% and -30.9 ± 4.1%, respectively, p < 0.0001). CONCLUSIONS (1) The BON-1 cell line is a representative model for studying the IGF system in GEP-NETs, (2) BON-1 cells produce growth factors (IGF2) activating IR-A, and (3) combined SSTR and D2R targeting with PAS + CAB and BIM-23A760 suppresses IGF2-induced IR-A activation.
Collapse
MESH Headings
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Cell Line, Tumor/chemistry
- Culture Media, Conditioned/pharmacology
- Dopamine/analogs & derivatives
- Dopamine/pharmacology
- Dopamine Agonists/pharmacology
- Enzyme-Linked Immunosorbent Assay
- Gene Expression Regulation, Neoplastic/drug effects
- HEK293 Cells
- Humans
- Insulin-Like Growth Factor II/metabolism
- Intestinal Neoplasms/pathology
- Neuroendocrine Tumors/pathology
- Pancreatic Neoplasms/pathology
- RNA, Messenger/metabolism
- Receptor, Insulin/genetics
- Receptor, Insulin/metabolism
- Receptors, Dopamine D2/genetics
- Receptors, Dopamine D2/metabolism
- Receptors, Somatostatin/genetics
- Receptors, Somatostatin/metabolism
- Somatostatin/analogs & derivatives
- Somatostatin/pharmacology
- Stomach Neoplasms/pathology
- Transfection
Collapse
Affiliation(s)
- Roxanne C S van Adrichem
- Division of Endocrinology, Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Redko B, Ragozin E, Andreii B, Helena T, Amnon A, Talia SZ, Mor OH, Genady K, Gary G. Synthesis, drug release, and biological evaluation of new anticancer drug-bioconjugates containing somatostatin backbone cyclic analog as a targeting moiety. Biopolymers 2015; 104:743-52. [DOI: 10.1002/bip.22694] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 05/12/2015] [Accepted: 05/27/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Boris Redko
- Department of Biological Chemistry; Ariel University; Ariel 40700 Israel
- Department of Chemistry; The Julius Spokojny Bioorganic Chemistry Laboratory; Bar Ilan University; Ramat Gan 52900 Israel
| | - Elena Ragozin
- Department of Biological Chemistry; Ariel University; Ariel 40700 Israel
| | - Bazylevich Andreii
- Department of Biological Chemistry; Ariel University; Ariel 40700 Israel
| | - Tuchinsky Helena
- Department of Molecular Biology; Ariel University; Ariel 40700 Israel
| | - Albeck Amnon
- Department of Chemistry; The Julius Spokojny Bioorganic Chemistry Laboratory; Bar Ilan University; Ramat Gan 52900 Israel
| | - Shekhter Zahavi Talia
- Department of Molecular Microbiology and Biotechnology; George S. Wise Faculty of Life Sciences; Tel-Aviv University; Tel-Aviv 69978 Israel
| | - Oron-Herman Mor
- The Advanced Technologies Center; Sheba Medical Center; Tel Hashomer 52621 Israel
| | - Kostenich Genady
- The Advanced Technologies Center; Sheba Medical Center; Tel Hashomer 52621 Israel
| | - Gellerman Gary
- Department of Biological Chemistry; Ariel University; Ariel 40700 Israel
| |
Collapse
|
23
|
Ferro JNDS, de Aquino FLT, de Brito RG, dos Santos PL, Quintans JDSS, de Souza LC, de Araújo AF, Diaz BL, Lucca-Júnior W, Quintans-Júnior LJ, Barreto E. Cyclo-Gly-Pro, a cyclic dipeptide, attenuates nociceptive behaviour and inflammatory response in mice. Clin Exp Pharmacol Physiol 2015; 42:1287-95. [DOI: 10.1111/1440-1681.12480] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 05/08/2015] [Accepted: 08/08/2015] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | | | - Lucas Costa de Souza
- Laboratory of Inflammation; Federal University of Rio de Janeiro; Rio de Janeiro Brazil
| | | | - Bruno Lourenço Diaz
- Laboratory of Inflammation; Federal University of Rio de Janeiro; Rio de Janeiro Brazil
| | | | | | - Emiliano Barreto
- Laboratory of Cell Biology; Federal University of Alagoas; Maceió Brazil
| |
Collapse
|
24
|
Synthetic Peptide Analogs of Somatostatin: Trends in the Synthesis of and Prospects in the Search for New Anticancer Drugs. Pharm Chem J 2015. [DOI: 10.1007/s11094-015-1284-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
25
|
Fernández-Llamazares AI, Spengler J, Albericio F. Review backboneN-modified peptides: How to meet the challenge of secondary amine acylation. Biopolymers 2015; 104:435-52. [DOI: 10.1002/bip.22696] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 05/21/2015] [Accepted: 05/26/2015] [Indexed: 12/29/2022]
Affiliation(s)
- Ana I. Fernández-Llamazares
- Institute for Research in Biomedicine; Deparment of Chemistry and Molecular Pharmacology, Barcelona Science Park; Baldiri Reixac 10 Barcelona 08028 Spain
- CIBER-BBN; Networking Centre on Bioengineering, Biomaterials and Nanomedicine, Barcelona Science Park; Baldiri Reixac 10 Barcelona 08028 Spain
| | - Jan Spengler
- Institute for Research in Biomedicine; Deparment of Chemistry and Molecular Pharmacology, Barcelona Science Park; Baldiri Reixac 10 Barcelona 08028 Spain
- CIBER-BBN; Networking Centre on Bioengineering, Biomaterials and Nanomedicine, Barcelona Science Park; Baldiri Reixac 10 Barcelona 08028 Spain
| | - Fernando Albericio
- Institute for Research in Biomedicine; Deparment of Chemistry and Molecular Pharmacology, Barcelona Science Park; Baldiri Reixac 10 Barcelona 08028 Spain
- CIBER-BBN; Networking Centre on Bioengineering, Biomaterials and Nanomedicine, Barcelona Science Park; Baldiri Reixac 10 Barcelona 08028 Spain
- Department of Organic Chemistry; University of Barcelona; Martí i Franquès 1-11 Barcelona 08028 Spain
- School of Chemistry and Physics; University of KwaZulu-Natal; 4001 Durban South Africa
- School of Life Sciences, Department of Chemistry, Yachay Tech, Yachay City of Knowledge; Urcuquι 100119 Ecuador. Department of Chemistry; College of Science, King Saud University; P.O. Box 2455 Riyadh 11451 Saudi Arabia
| |
Collapse
|
26
|
Öberg K. Neuroendocrine gastro-enteropancreatic tumors - from eminence based to evidence-based medicine - A Scandinavian view. Scand J Gastroenterol 2015; 50:727-39. [PMID: 25855088 DOI: 10.3109/00365521.2015.1033001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Neuroendocrine tumors (NETs) comprise a heterogenous group of neoplasms with variable clinical expression and progression. The primary tumors most frequently occur in the lungs, intestine and the pancreas. The NET incidence is approximately 6.1/100,000 per year with a prevalence higher than 35/100,000 per year. A NET may be functioning with symptoms related to hormone overproduction or non-functioning, not presenting any hormone-related symptoms. From the early 1980s and onwards, Uppsala University Hospital has contributed significantly to diagnosis, just to mention immunohistochemistry, radio-immunoassays for hormones and peptides and molecular imaging. On the therapeutic side, treatments with cytotoxics as well as biologicals such as, somatostatin analogs and interferons have been evaluated. We have furthermore been involved in important phase III trials for registration of so called, new targeted agents such as, RADIANT-3 and RADIANT-2. Our group were also the first to localize the gene for MEN I on chromosome 11 locus q13. Most recent developments have been the establishments of new biomarkers such as, olfactory receptor E51E1 as well as micro-RNAs in carcinoid tumors of the intestine and lung. A new oncolytic virus, Ad-Vince, for treatment of most NETs has been developed and is ready for the clinic. Furthermore, we have been involved in establishing Nordic and international collaborations. Today, NETs is an area with rapid development and recognized by international organizations at conferences, with large attendance. The Nordic countries continue to be significant contributors to the field.
Collapse
Affiliation(s)
- Kjell Öberg
- Department of Endocrine Oncology, Uppsala University Hospital , Entrance 40, 5th floor, SE-751 85 Uppsala , Sweden
| |
Collapse
|
27
|
Giustina A, Mazziotti G, Maffezzoni F, Amoroso V, Berruti A. Investigational drugs targeting somatostatin receptors for treatment of acromegaly and neuroendocrine tumors. Expert Opin Investig Drugs 2014; 23:1619-35. [DOI: 10.1517/13543784.2014.942728] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
28
|
Abstract
INTRODUCTION Acromegaly is a rare disease that severely impacts patients' health all the while, being a slowly progressing illness. In the past decades, advancements in treatment modalities, especially development of new drugs, as well as focused guidelines has improved management of acromegaly. Still, many patients are considered not sufficiently treated and there remains an ongoing need for further development. AREAS COVERED This article reviews new medical treatments currently under clinical investigation (such as pasireotide, oral octreotide and somatoprim) and under experimental development (such as octreotide implants, CAM2029 and ATL-1103). EXPERT OPINION As it seems unlikely that one single agent may achieve cure in 100% of cases, there is an urgent need for new agents that help patients where current medication fails. Imperatively, this means we have to improve our understanding of the underlying pathogenetic and molecular mechanisms.
Collapse
Affiliation(s)
- Sylvère Störmann
- Klinikum der Universität München, Medizinische Klinik und Poliklinik IV , Ziemssenstr. 1, 80336 München , Germany +49 0 89 5160 2111 ; +49 0 89 5160 2194 ;
| | | |
Collapse
|
29
|
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.
Collapse
Affiliation(s)
- Jean Claude Reubi
- Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland.
| | | |
Collapse
|
30
|
Veenstra MJ, de Herder WW, Feelders RA, Hofland LJ. Targeting the somatostatin receptor in pituitary and neuroendocrine tumors. Expert Opin Ther Targets 2013; 17:1329-43. [DOI: 10.1517/14728222.2013.830711] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
31
|
Fleseriu M, Petersenn S. New avenues in the medical treatment of Cushing's disease: corticotroph tumor targeted therapy. J Neurooncol 2013; 114:1-11. [PMID: 23673515 PMCID: PMC3724972 DOI: 10.1007/s11060-013-1151-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 05/06/2013] [Indexed: 01/23/2023]
Abstract
Cushing's disease (CD) is a condition of chronic hypercortisolism caused by an adrenocorticotropic hormone-secreting pituitary adenoma. First-line transsphenoidal surgery is not always curative and disease sometimes recurs. Radiotherapy often requires months or years to be effective, and is also not curative in many cases. Consequently, effective medical therapies for patients with CD are needed. Corticotroph adenomas frequently express both dopamine (D2) and somatostatin receptors (predominantly sstr5). Pasireotide, a somatostatin analog with high sstr5 binding affinity, has shown urinary free cortisol (UFC) reductions in most patients with CD in a large phase 3 trial, with UFC normalization and tumor shrinkage in a subset of patients. Adverse events were similar to other somatostatin analogs, with the exception of the degree and severity of hyperglycemia. Two small trials (one prospective and one retrospective) have suggested that cabergoline, a D2 receptor agonist, could be effective in normalizing UFC, but current long-term data results are conflicting. Combination treatment with pasireotide plus cabergoline and the adrenal steroidogenesis inhibitor ketoconazole has been successful, but further investigation in larger trials is necessary. Retinoic acid also showed interesting results in a recent very small prospective study. Glucocorticoid receptor blockade with mifepristone has recently demonstrated improvement in signs and symptoms of Cushing's and glycemic control; however, this modality does not address the etiology of the disease and has inherent adverse events related to its mechanism of action. Pituitary-targeted medical therapies will soon play a more prominent role in treating CD, and may potentially become first-line medical therapy when surgery fails or is contraindicated.
Collapse
Affiliation(s)
- Maria Fleseriu
- Departments of Medicine and Neurological Surgery, and Northwest Pituitary Center, Oregon Health & Science University, Portland, OR 97239, USA.
| | | |
Collapse
|
32
|
Plöckinger U. Medical therapy of acromegaly. Int J Endocrinol 2012; 2012:268957. [PMID: 22550484 PMCID: PMC3328958 DOI: 10.1155/2012/268957] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Revised: 12/20/2011] [Accepted: 01/09/2012] [Indexed: 12/18/2022] Open
Abstract
This paper outlines the present status of medical therapy of acromegaly. Indications for permanent postoperative treatment, postirradiation treamtent to bridge the interval until remission as well as primary medical therapy are elaborated. Therapeutic efficacy of the different available drugs-somatostatin receptor ligands (SRLs), dopamine agonists, and the GH antagonist Pegvisomant-is discussed, as are the indications for and efficacy of their respective combinations. Information on their mechanism of action, and some pharmakokinetic data are included. Special emphasis is given to the difficulties to define remission criteria of acromegaly due to technical assay problems. An algorithm for medical therapy in acromegaly is provided.
Collapse
Affiliation(s)
- U. Plöckinger
- Interdisziplinäres Stoffwechsel-Centrum, Charité-Universitätsmedizin Berlin, Campus Virchow-Klinikum, 13353 Berlin, Germany
- *U. Plöckinger:
| |
Collapse
|
33
|
Ovadia O, Greenberg S, Laufer B, Gilon C, Hoffman A, Kessler H. Improvement of drug-like properties of peptides: the somatostatin paradigm. Expert Opin Drug Discov 2010; 5:655-71. [DOI: 10.1517/17460441.2010.493935] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
34
|
Linde Y, Ovadia O, Safrai E, Xiang Z, Portillo FP, Shalev DE, Haskell-Luevano C, Hoffman A, Gilon C. Structure-activity relationship and metabolic stability studies of backbone cyclization and N-methylation of melanocortin peptides. Biopolymers 2008; 90:671-82. [PMID: 18655141 DOI: 10.1002/bip.21057] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Backbone cyclization (BC) and N-methylation have been shown to enhance the activity and/or selectivity of biologically active peptides and improve metabolic stability and intestinal permeability. In this study, we describe the synthesis, structure-activity relationship (SAR) and intestinal metabolic stability of a backbone cyclic peptide library, BL3020, based on the linear alpha-Melanocyte stimulating hormone analog Phe-D-Phe-Arg-Trp-Gly. The drug lead, BL3020-1, selected from the BL3020 library (compound 1) has been shown to inhibit weight gain in mice following oral administration. Another member of the BL3020 library, BL3020-17, showed improved biological activity towards the mMC4R, in comparison to BL3020-1, although neither were selective for MC4R or MC5R. N-methylation, which restrains conformational freedom while increasing metabolic stability beyond that which is imparted by BC, was used to find analogs with increased selectivity. N-methylated backbone cyclic libraries were synthesized based on the BL3020 library. SAR studies showed that all the N-methylated backbone cyclic peptides demonstrated reduced biological activity and selectivity for all the analyzed receptors. N-methylation of active backbone cyclic peptides destabilized the active conformation or stabilized an inactive conformation, rendering the peptides biologically inactive. N-methylation of backbone cyclic peptides maintained stability to degradation by intestinal enzymes.
Collapse
Affiliation(s)
- Yaniv Linde
- Institute of Chemistry, Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
The Effect of Transforming Growth Factor β on Human Neuroendocrine Tumor BON Cell Proliferation and Differentiation Is Mediated through Somatostatin Signaling. Mol Cancer Res 2008; 6:1029-42. [DOI: 10.1158/1541-7786.mcr-07-2073] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
36
|
Cheng W, Lim LY. Comparison of Reversible and Nonreversible Aqueous-Soluble Lipidized Conjugates of Salmon Calcitonin. Mol Pharm 2008; 5:610-21. [DOI: 10.1021/mp8000167] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Weiqiang Cheng
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Singapore 117543, and Pharmacy, School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Lee-Yong Lim
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Singapore 117543, and Pharmacy, School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| |
Collapse
|
37
|
Hess S, Linde Y, Ovadia O, Safrai E, Shalev DE, Swed A, Halbfinger E, Lapidot T, Winkler I, Gabinet Y, Faier A, Yarden D, Xiang Z, Portillo FP, Haskell-Luevano C, Gilon C, Hoffman A. Backbone cyclic peptidomimetic melanocortin-4 receptor agonist as a novel orally administrated drug lead for treating obesity. J Med Chem 2008; 51:1026-34. [PMID: 18220330 DOI: 10.1021/jm701093y] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The tetrapeptide sequence His-Phe-Arg-Trp, derived from melanocyte-stimulating hormone (alphaMSH) and its analogs, causes a decrease in food intake and elevates energy utilization upon binding to the melanocortin-4 receptor (MC4R). To utilize this sequence as an effective agent for treating obesity, we improved its metabolic stability and intestinal permeability by synthesizing a library of backbone cyclic peptidomimetic derivatives. One analog, peptide 1 (BL3020-1), was selected according to its selectivity in activating the MC4R, its favorable transcellular penetration through enterocytes and its enhanced intestinal metabolic stability. This peptide was detected in the brain following oral administration to rats. A single oral dose of 0.5 mg/kg in mice led to reduced food consumption (up to 48% vs the control group) that lasted for 5 h. Repetitive once daily oral dosing (0.5 mg/kg/day) for 12 days reduced weight gain. Backbone cyclization was shown to produce a potential drug lead for treating obesity.
Collapse
Affiliation(s)
- Shmuel Hess
- Department of Pharmaceutics, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 91120, Israel
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Hess S, Ovadia O, Shalev DE, Senderovich H, Qadri B, Yehezkel T, Salitra Y, Sheynis T, Jelinek R, Gilon C, Hoffman A. Effect of structural and conformation modifications, including backbone cyclization, of hydrophilic hexapeptides on their intestinal permeability and enzymatic stability. J Med Chem 2007; 50:6201-11. [PMID: 17983214 DOI: 10.1021/jm070836d] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A library of 18 hexapeptide analogs was synthesized, including sub-libraries of N- or C-methylation of the parent hexapeptide Phe-Gly-Gly-Gly-Gly-Phe, as well as backbone cyclized analogs of each linear analog with various ring sizes. N- or C-methylation as well as cyclization (but not backbone cyclization) have been suggested to improve intestinal permeability and metabolic stability of peptides in general. Here we aimed to assess their applicability to hydrophilic peptides. The intestinal permeability (Papp) of the 18-peptide library was in the range of 0.2-6.8 x 10-6 cm/sec. Based on several tests, we concluded that the absorption mechanism of all tested analogs is paracellular, regardless of the structural or conformational modifications. In all cases, backbone cyclization increased Papp (5-fold) in comparison to the linear analogs due to the smaller 3D size and also dramatically decreased peptide proteolysis by brush border enzymes. N- or C-methylation did not enhance the permeability of the linear analogs in this series.
Collapse
Affiliation(s)
- Shmuel Hess
- Departments of Pharmaceutics and Organic Chemistry, and the Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Safra Campus, Jerusalem 91904, Israel
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Ludvigsen E. Somatostatin receptor expression and biological functions in endocrine pancreatic cells: review based on a doctoral thesis. Ups J Med Sci 2007; 112:1-20. [PMID: 17578804 DOI: 10.3109/2000-1967-091] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Type 1 diabetes is resulting from the selective destruction of insulin-producing betacells within the pancreatic islets. Somatostatin acts as an inhibitor of hormone secretion through specific receptors (sst1-5). All ssts were expressed in normal rat and mouse pancreatic islets, although the expression intensity and the co-expression pattern varied between ssts as well as between species. This may reflect a difference in response to somatostatin in islet cells of the two species. The Non-Obese Diabetic (NOD) mouse model is an experimental model of type 1 diabetes, with insulitis accompanied by spontaneous hyperglycaemia. Pancreatic specimens from NOD mice at different age and stage of disease were stained for ssts. The islet cells of diabetic NOD mice showed increased islet expression of sst2-5 compared to normoglycemic NOD mice. The increase in sst2-5 expression in the islets cells may suggest either a contributing factor in the process leading to diabetes, or a defense response against ongoing beta-cell destruction. Somatostatin analogues were tested on a human endocrine pancreatic tumour cell line and cultured pancreatic islets. Somatostatin analogues had an effect on cAMP accumulation, chromogranin A secretion and MAP kinase activity in the cell line. Treatment of rat pancreatic islets with somatostatin analogues with selective receptor affinity was not sufficient to induce an inhibition of insulin and glucagon secretion. However, a combination of selective analogues or non-selective analogues via costimulation of receptors can cause inhibition of hormone production. For insulin and glucagon, combinations of sst2 + sst5 and sst1 + sst2, respectively, showed a biological effect. In summary, knowledge of islet cell ssts expression and the effect of somatostatin analogues with high affinity to ssts may be valuable in the future attempts to influence beta-cell function in type 1 diabetes mellitus, since down-regulation of beta-cell function may promote survival of these cells during the autoimmune attack.
Collapse
Affiliation(s)
- Eva Ludvigsen
- Department of Medical Cell Biology, Uppsala universitet.
| |
Collapse
|
40
|
Cheng W, Satyanarayanajois S, Lim LY. Aqueous-Soluble, Non-Reversible Lipid Conjugate of Salmon Calcitonin: Synthesis, Characterization and In Vivo Activity. Pharm Res 2006; 24:99-110. [PMID: 17109213 DOI: 10.1007/s11095-006-9128-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Accepted: 07/18/2006] [Indexed: 10/23/2022]
Abstract
PURPOSE A novel, non-reversible, aqueous-based lipidization strategy with palmitic acid as a model lipid was evaluated for conjugation with salmon calcitonin (sCT). MATERIALS AND METHODS A water-soluble epsilon-maleimido lysine derivative of palmitic acid was synthesized from reaction of palmitic acid N-succinimidyl ester and epsilon-maleimido lysine. The latter was generated from reaction of alpha-Boc-lysine and methylpyrrolecarboxylate, with subsequent deprotection of the Boc group. The palmitic derivative was further conjugated with sCT via a thio-ether bond to produce Mal-sCT in aqueous solution. The identity and purity of Mal-sCT was confirmed by Electrospray Ionisation Mass spectrometry (ESI-MS) and HPLC. RESULTS Yield of Mal-sCT was 83%. Dynamic light scattering and circular dichroism data suggested that Mal-sCT presented as a stable helical structure in aqueous solutions of varying polarity, with a propensity to aggregate at concentrations above 11 microM. Cellular uptake of Mal-sCT was twice that of sCT in the Caco-2 cell model, and the conjugate was more resistant to liver enzyme degradation. Mal-sCT exhibited comparable hypocalcemic activity to sCT when administered subcutaneously in the rat model at sCT equivalent dose of 0.114 mg/kg. Peroral Mal-sCT, however, produced variability in therapeutic outcome. While four out of six rats did not respond following intragastric gavage with Mal-sCT, two rats showed significantly suppressed plasma calcium levels (approximately 60% of baseline) for up to 10 h. CONCLUSION A novel non-reversible, water-soluble lipid conjugate of sCT was successfully synthesized that showed (1) different aggregation behavior and secondary structure, (2) improved enzymatic stability and cellular uptake, and (3) comparable hypocalcemic activity in vivo compared to sCT.
Collapse
Affiliation(s)
- Weiqiang Cheng
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore
| | | | | |
Collapse
|
41
|
Abstract
There is an increasing number of patients with diabetes mellitus in many countries. Diabetic kidney disease, one of its microvascular complications, is also increasing markedly and has become a major cause of end stage renal disease worldwide. Intervention for preventing and delaying the development and progression of diabetic kidney disease is not only a medical concern, but also a social issue. Despite extensive efforts, however, medical interventions thus far are not effective enough to prevent the progression of the disease and the development of end stage renal disease. This justifies attempts to develop novel therapeutic approaches for diabetic nephropathy. Recent insights on its pathogenesis and progression have suggested new targets for the specific treatment of this disease. They include aldosterone, aldose reductase, arachidonic acid metabolites, growth factors, advanced glycosylation end-products, peroxisome proliferator-activated receptors and endothelin. Several other biochemical mediators have been targeted in experimental animal models with the goal to prevent diabetic nephropathy progression, but translation to clinics of these experimental achievements are still limited or lacking.
Collapse
Affiliation(s)
- Simona Bruno
- Mario Negri Institute for Pharmacological Research, Department of Medicine and Transplantation, Ospedali Riuniti di Bergamo, Via Gavazzeni 11, 24125 Bergamo, Italy
| | | | | | | |
Collapse
|
42
|
Following are the abstracts from the Fourth Annual Meeting of the Society for Molecular Imaging. Mol Imaging 2005. [DOI: 10.1162/15353500200500210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Declaration of Financial Interests or Relationships To insure balance, independence, objectivity and scientific rigor in all CME programs it is the policy of the meeting's joint sponsors that any speaker or poster presenter who makes a presentation at a program designated for AMA Physician's Recognition Award (PRA) Category 1 or 2 credit must disclose any real or apparent financial interest or other relationship (i.e., grants, research support, consultant, honoraria) that the presenter may have with the manufacturers, distributors or providers of any commercial products or services that may be discussed in the presentation. ISMRM and SMI do not imply that such financial interests or relationships are inherently improper or that such interests or relationships would prevent the presenter from making an objective presentation. However, it is imperative that such financial interests or relationships be identified by the presenter so that participants at the CME activity may have these facts fully disclosed prior to the presentation, and may form their own judgments about the presentation. Towards this end, the information provided by each presenter can be found at the bottom of each abstract. Every speaker, abstract presenter, organizer or anyone else who has control over any content in this meeting has been required to submit a Declaration of Financial Interests or Relationships, even if there is no conflict or relationship to declare.
Collapse
|
43
|
Fukami K, Cooper ME, Forbes JM. Agents in development for the treatment of diabetic nephropathy. Expert Opin Investig Drugs 2005; 14:279-94. [PMID: 15833059 DOI: 10.1517/13543784.14.3.279] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Diabetic nephropathy is a leading cause of end-stage renal disease, and accounts for significant morbidity and mortality in patients with diabetes. Diabetic nephropathy seems to occur as a result of an interaction between metabolic and haemodynamic factors, which activate common pathways that lead to renal damage. In the past, the treatment of diabetic nephropathy has focused on the control of hyperglycaemia. Newer targets, some of which are linked to glucose-dependent pathways, appear to be a major focus of new treatments directed against the development and progression of renal damage as a result of diabetes. It is anticipated that additional therapeutic approaches that inhibit both metabolic and haemodynamic pathways will include strategies that target growth factors, cytokines and intracellular second messengers. Such an approach is expected to lead to improved therapies for the treatment of diabetic nephropathy.
Collapse
Affiliation(s)
- Kei Fukami
- Danielle Alberti Memorial Centre for Diabetes Complications, Baker Heart Research Institute, PO Box 6492, St Kilda Rd Central, Melbourne, Victoria 8008, Australia.
| | | | | |
Collapse
|
44
|
Ludvigsen E, Stridsberg M, Taylor JE, Culler MD, Oberg K, Janson ET. Subtype selective interactions of somatostatin and somatostatin analogs with sst1, sst2, and sst5 in BON-1 cells. Med Oncol 2005; 21:285-95. [PMID: 15456957 DOI: 10.1385/mo:21:3:285] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2004] [Accepted: 03/24/2004] [Indexed: 01/02/2023]
Abstract
Somatostatin is a polypeptide hormone acting as an inhibitor of pituitary, pancreatic, and gastrointestinal secretion through specific membrane receptors of which five subtypes have been cloned (sst(1-5)). Somatostatin analogs are used in the clinic to treat patients with excessive hormone production due to a neuroendocrine tumor. The aim of this study was to investigate the biological activity of three new somatostatin receptor subtype selective analogs (BIM-23926, sst(1)-selective; BIM-23120, sst(2)-selective; and BIM-23206, sst(5)-selective) in the human neuroendocrine tumor cell line, BON-1, which expresses sst(1), sst(2), and sst(5) natively. Somatostatin-14 and octreotide were used as reference substances. Forskolin-induced cAMP accumulation and chromogranin A (CgA) secretion were inhibited by BIM-23120, BIM-23206, and somatostatin-14 in a dose-dependent manner. Cholecystokinin (CCK-8) stimulated activation of mitogen-activated protein (MAP) kinase was inhibited by BIM-23120 and BIM-23206, while BIM-23926 stimulated the activity. Selective BIM analogs showed a more efficient inhibitory effect on cAMP accumulation, CgA secretion, and MAP kinase activity than octreotide in BON-1 cells. This may be explained by the differences in affinity of the ligand to the receptor or by interaction between different sst subtypes. We conclude that increasing knowledge about sst physiology and expression in malignant disease indicates a need for new analogs that can be incorporated into the therapeutic arsenal.
Collapse
Affiliation(s)
- Eva Ludvigsen
- Department of Medical Sciences, University Hospital, 751 85 Uppsala, Sweden
| | | | | | | | | | | |
Collapse
|
45
|
|
46
|
Shimon I, Rubinek T, Hadani M, Alhadef N. PTR-3173 (somatoprim), a novel somatostatin analog with affinity for somatostatin receptors 2, 4 and 5 is a potent inhibitor of human GH secretion. J Endocrinol Invest 2004; 27:721-7. [PMID: 15636423 DOI: 10.1007/bf03347512] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
SS, a natural cyclic tetradecapeptide, is a potent suppressor of pituitary GH and TSH secretion. At least five distinct SS receptor (SSTR) subtypes have been cloned and termed SSTRs 1-5. Both SSTR2 and SSTR5 regulate human GH and TSH secretion. Recently, a novel enzymatically stable SS analog, PTR-3173 (Somatoprim), with affinity for human SSTR2, SSTR4 and SSTR5, has been identified. This cyclic heptapeptide analog suppressed rat GH in vivo with no effect on insulin and minimal effect on glucagon secretion. Using primary cultures of human fetal pituitaries (20-24-week gestation) and GH-secreting adenomas, we studied the in vitro inhibitory effects of PTR-3173 on human pituitary secretion. PTR-3173 suppressed GH release from both fetal pituitaries (maximal suppression of 54% with 10 nM) and cultures of GH-cell adenomas (35% suppression with 100 nM). Octreotide and PTR-3173 had comparable inhibitory effects on GH secretion from fetal human pituitaries. TSH was mildly suppressed by PTR-3173, whereas ACTH secretion was not affected in fetal pituitary cultures. In cultures of eight GH-secreting adenomas, octreotide was superior to PTR-3173 in suppressing GH from two adenomas, PTR-3173 was more potent in three other tumors, and three adenomas did not respond significantly to either analog. PTR-3173 suppressed PRL in several mixed GH-PRL adenomas. In conclusion, PTR-3173, a novel SS analog with a unique SSTRs binding combination, is a potent in vitro suppressor of human GH. Combining this inhibitory effect with the lack of effect on insulin secretion, it is suggested that PTR-3173 may be clinically useful for the treatment of acromegaly.
Collapse
Affiliation(s)
- I Shimon
- Institute of Endocrinology, Chaim Sheba Medical Center, Tel-Hashomer, Israel.
| | | | | | | |
Collapse
|
47
|
Weckbecker G, Lewis I, Albert R, Schmid HA, Hoyer D, Bruns C. Opportunities in somatostatin research: biological, chemical and therapeutic aspects. Nat Rev Drug Discov 2004; 2:999-1017. [PMID: 14654798 DOI: 10.1038/nrd1255] [Citation(s) in RCA: 402] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Gisbert Weckbecker
- Transplantation and Immunology, Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4002 Basel, Switzerland.
| | | | | | | | | | | |
Collapse
|
48
|
Erchegyi J, Penke B, Simon L, Michaelson S, Wenger S, Waser B, Cescato R, Schaer JC, Reubi JC, Rivier J. Novel sst(4)-selective somatostatin (SRIF) agonists. 2. Analogues with beta-methyl-3-(2-naphthyl)alanine substitutions at position 8. J Med Chem 2004; 46:5587-96. [PMID: 14667213 DOI: 10.1021/jm0302445] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We present a family of human sst(4)-selective, high-affinity (IC(50) = 2-4 nM) cyclic somatostatin (SRIF) octapeptides. These peptides result from the substitution of dTrp(8) in H-c[Cys(3)-Phe(6)-Phe(7)-DTrp(8)-Lys(9)-Thr(10)-Phe(11)-Cys(14)]-OH (SRIF numbering) (ODT-8) by one of the four conformationally biased stereoisomers of beta-methyl-3-(2-naphthyl)alanine (beta-Me2Nal). Whereas H-c[Cys-Phe-Phe-DNal-Lys-Thr-Phe-Cys]-OH (ODN-8, 2) has high affinity and marginal selectivity for human sst(3) (Reubi et al., Proc. Natl. Acad. Sci. U.S.A. 2000, 97, 13973-13978), H-c[Cys-Phe-Tyr-D-threo-beta-Me2Nal-Lys-Thr-Phe-Cys]-OH (5) has high affinity for all sst's except for sst(1); H-c[Cys-Phe-Tyr-L-threo-beta-Me2Nal-Lys-Thr-Phe-Cys]-OH (6) has high affinity for sst(4) (IC(50) = 2.1 nM), with more than 50-fold selectivity toward the other receptors. Analogues 7 and 8, containing d- and l-erythro-beta-Me2Nal instead of the corresponding threo derivatives at position 8, are essentially inactive at all receptors. Substitution of Tyr(7) in 5 and 6 by Aph(7) resulted in 9 and 10 with similar affinity patterns overall yet lowered affinity. The substitution of DCys(3) for Cys(3) in 5 and 6 yielded H-c[DCys-Phe-Tyr-D-threo-beta-Me2Nal-Lys-Thr-Phe-Cys]-OH (11) and H-c[DCys-Phe-Tyr-L-threo-beta-Me2Nal-Lys-Thr-Phe-Cys]-OH (12), with biological profiles almost identical to those of their parents 5 and 6 (i.e., high affinity for sst(2-5) for 11 and high affinity and selectivity for sst(4) for 12). Analogue 12, with high sst(4) affinity combined with the highest sst(4) selectivity among all tested compounds, is an agonist in the cAMP accumulation assay (EC(50) = 1.29 nM). Cold monoiodination of 12 yielded 14, with loss of sst(4) selectivity and loss of high affinity (IC(50) = 21 nM). Introduction of Tyr(2) in 9 and 10 and substitution of Cys(3) by dCys(3), to yield 15 and 16 (IC(50) = 9.8 and 61 nM, respectively, for sst(4) and limited selectivity), failed to generate a high-affinity (125)iodinatable sst(4)-selective ligand. Substitution of Phe by Tyr at position 11 in H-c[DCys-Phe-Phe-L-threo-beta-Me2Nal-Lys-Thr-Phe-Cys]-OH yielded 18 (IC(50) = 11.8 nM at sst(4)), with limited sst(4) selectivity (30-fold or greater at the other receptors) yet only slightly improved affinity over that of 14. Cold monoiodination of 18 yielded 20 (IC(50) = 30 nM at sst(4) and high selectivity). Whereas we were able, in this study, to identify a new family of sst(4)-selective, high-affinity compounds, our additional goal, to identify highly potent and sst(4)-selective ligands amenable to (125)iodination, could not be achieved satisfactorily. On the other hand, some of the diastereomers identified in this study, such as 5, 11, 17, and 19, are very potent ligands at all receptors but sst(1).
Collapse
Affiliation(s)
- Judit Erchegyi
- The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
This review provides an overview of traditional as well as emerging therapies useful in the management of pediatric short bowel syndrome. Pediatric short bowel syndrome is relatively uncommon; however, when it does occur, it presents a unique challenge to medical care providers. The use of parenteral and enteral nutrition to maximize growth and enhance intestinal adaptation so as to increase absorptive surface area has been the primary focus of therapy. In recent years, the advent of pharmacologic advances, including the use of antibacterial drugs, anti-motility drugs and hormonal therapies, has had a significant impact on this condition. At times, surgery may be indicated for dealing with complications, or providing alternative therapy such as transplantation. With ongoing research, it is likely that improved pharmacologic therapy will be available for enhanced intestinal adaptation, control of gut motility, treatment of small bowel bacterial overgrowth, and treatment of rejection following small intestinal transplantation.
Collapse
Affiliation(s)
- Jon A Vanderhoof
- Department of Pediatric Gastroenterology and Nutrition, University of Nebraska Medical Center, Omaha, Nebraska 68198-5160, USA.
| | | | | |
Collapse
|
50
|
Fjällskog ML, Ludvigsen E, Stridsberg M, Oberg K, Eriksson B, Janson ET. Expression of somatostatin receptor subtypes 1 to 5 in tumor tissue and intratumoral vessels in malignant endocrine pancreatic tumors. Med Oncol 2003; 20:59-67. [PMID: 12665686 DOI: 10.1385/mo:20:1:59] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2002] [Accepted: 11/20/2002] [Indexed: 01/02/2023]
Abstract
Somatostatin analogs are well established in the treatment of malignant endocrine pancreatic tumors (EPTs). Our goal is to individualize their treatment using receptor-subtype-specific analogs and, therefore, exploring the receptor expression is highly important. We have examined the expression of somatostatin receptor (sst) subtypes 1-5 on tumor cells and in intratumoral vessels in 28 tumor tissues from malignant EPTs with immunohistochemistry using sst-subtype-specific polyclonal antibodies. We found that sst(2) and sst(4) stained positive in 90% and sst(1) in 70% of the tumor tissues, whereas sst(3) and sst(5) stained positive in only 50% of the tumor tissues. Sst expression in intratumoral vessels was high for sst(2) and sst(4) (80%), moderate for sst(1) (40%), and low for sst(3) and sst(5) (10%). The ssts were evenly distributed among the different tumor subtypes. However, tumors belonging to the same subgroup of EPTs showed a variable expression of receptor subtypes. No differences in receptor-subtype expression could be seen between poorly and welldifferentiated tumors, nor between primary tumors and metastases. Prior medical treatment did not influence sst expression pattern. In conclusion, sst(2) and sst(4) were expressed in most tumor tissues and intratumoral vessels from EPTs. However, sst(3) and sst(5) were lacking in half of the tumor tissues and in most of the intratumoral vessels. These differences indicate the importance of determining each tumor s subset of receptors before treatment with receptor-subtype-specific analogs is initiated. The importance of sst expression in intratumoral vessels is not yet known.
Collapse
|