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Börzsei R, Zsidó BZ, Bálint M, Helyes Z, Pintér E, Hetényi C. Exploration of Somatostatin Binding Mechanism to Somatostatin Receptor Subtype 4. Int J Mol Sci 2022; 23:ijms23136878. [PMID: 35805885 PMCID: PMC9266823 DOI: 10.3390/ijms23136878] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/15/2022] [Accepted: 06/16/2022] [Indexed: 02/04/2023] Open
Abstract
Somatostatin (also named as growth hormone-inhibiting hormone or somatotropin release-inhibiting factor) is a regulatory peptide important for the proper functioning of the endocrine system, local inflammatory reactions, mood and motor coordination, and behavioral responses to stress. Somatostatin exerts its effects via binding to G-protein-coupled somatostatin receptors of which the fourth subtype (SSTR4) is a particularly important receptor mediating analgesic, anti-inflammatory, and anti-depressant effects without endocrine actions. Thus, SSTR4 agonists are promising drug candidates. Although the knowledge of the atomic resolution-binding modes of SST would be essential for drug development, experimental elucidation of the structures of SSTR4 and its complexes is still awaiting. In the present study, structures of the somatostatin–SSTR4 complex were produced using an unbiased, blind docking approach. Beyond the static structures, the binding mechanism of SST was also elucidated in the explicit water molecular dynamics (MD) calculations, and key binding modes (external, intermediate, and internal) were distinguished. The most important residues on both receptor and SST sides were identified. An energetic comparison of SST binding to SSTR4 and 2 offered a residue-level explanation of receptor subtype selectivity. The calculated structures show good agreement with available experimental results and indicate that somatostatin binding is realized via prerequisite binding modes and an induced fit mechanism. The identified binding modes and the corresponding key residues provide useful information for future drug design targeting SSTR4.
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Affiliation(s)
- Rita Börzsei
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, 7624 Pécs, Hungary; (R.B.); (B.Z.Z.); (M.B.); (Z.H.); (E.P.)
- János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, 7624 Pécs, Hungary
| | - Balázs Zoltán Zsidó
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, 7624 Pécs, Hungary; (R.B.); (B.Z.Z.); (M.B.); (Z.H.); (E.P.)
- János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, 7624 Pécs, Hungary
| | - Mónika Bálint
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, 7624 Pécs, Hungary; (R.B.); (B.Z.Z.); (M.B.); (Z.H.); (E.P.)
- János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, 7624 Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, 7624 Pécs, Hungary; (R.B.); (B.Z.Z.); (M.B.); (Z.H.); (E.P.)
- János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, 7624 Pécs, Hungary
- Algonist Gmbh, 1030 Vienna, Austria
- PharmInVivo Ltd., 7624 Pécs, Hungary
| | - Erika Pintér
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, 7624 Pécs, Hungary; (R.B.); (B.Z.Z.); (M.B.); (Z.H.); (E.P.)
- János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, 7624 Pécs, Hungary
- Algonist Gmbh, 1030 Vienna, Austria
- PharmInVivo Ltd., 7624 Pécs, Hungary
| | - Csaba Hetényi
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, 7624 Pécs, Hungary; (R.B.); (B.Z.Z.); (M.B.); (Z.H.); (E.P.)
- János Szentágothai Research Centre & Centre for Neuroscience, University of Pécs, 7624 Pécs, Hungary
- Correspondence:
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Moreno-Moreno P, Ibáñez-Costa A, Venegas-Moreno E, Fuentes-Fayos AC, Alhambra-Expósito MR, Fajardo-Montañana C, García-Martínez A, Dios E, Vázquez-Borrego MC, Remón-Ruiz P, Cámara R, Lamas C, Carlos Padillo-Cuenca J, Solivera J, Cano DA, Gahete MD, Herrera-Martínez AD, Picó A, Soto-Moreno A, Gálvez-Moreno MÁ, Castaño JP, Luque RM. Integrative Clinical, Radiological, and Molecular Analysis for Predicting Remission and Recurrence of Cushing Disease. J Clin Endocrinol Metab 2022; 107:e2938-e2951. [PMID: 35312002 DOI: 10.1210/clinem/dgac172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Adrenocorticotropin (ACTH)-secreting pituitary tumors (ACTHomas) are associated with severe comorbidities and increased mortality. Current treatments mainly focus on remission and prevention of persistent disease and recurrence. However, there are still no useful biomarkers to accurately predict the clinical outcome after surgery, long-term remission, or disease relapse. OBJECTIVES This work aimed to identify clinical, biochemical, and molecular markers for predicting long-term clinical outcome and remission in ACTHomas. METHODS A retrospective multicenter study was performed with 60 ACTHomas patients diagnosed between 2004 and 2018 with at least 2 years' follow-up. Clinical/biochemical variables were evaluated yearly. Molecular expression profile of the somatostatin/ghrelin/dopamine regulatory systems components and of key pituitary factors and proliferation markers were evaluated in tumor samples after the first surgery. RESULTS Clinical variables including tumor size, time until diagnosis/first surgery, serum prolactin, and postsurgery cortisol levels were associated with tumor remission and relapsed disease. The molecular markers analyzed were distinctly expressed in ACTHomas, with some components (ie, SSTR1, CRHR1, and MKI67) showing instructive associations with recurrence and/or remission. Notably, an integrative model including selected clinical variables (tumor size/postsurgery serum cortisol), and molecular markers (SSTR1/CRHR1) can accurately predict the clinical evolution and remission of patients with ACTHomas, generating a receiver operating characteristic curve with an area under the curve of 1 (P < .001). CONCLUSION This study demonstrates that the combination of a set of clinical and molecular biomarkers in ACTHomas is able to accurately predict the clinical evolution and remission of patients. Consequently, the postsurgery molecular profile represents a valuable tool for clinical evaluation and follow-up of patients with ACTHomas.
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Affiliation(s)
- Paloma Moreno-Moreno
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Service of Endocrinology and Nutrition, IMIBIC, HURS, 14004 Cordoba, Spain
| | - Alejandro Ibáñez-Costa
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain
| | - Eva Venegas-Moreno
- Unidad de Gestión de Endocrinología y Nutrición. Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - Antonio C Fuentes-Fayos
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain
| | - María R Alhambra-Expósito
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Service of Endocrinology and Nutrition, IMIBIC, HURS, 14004 Cordoba, Spain
| | - Carmen Fajardo-Montañana
- Department of Endocrinology, Hospital Universitario de La Ribera, Alzira, 46600, Valencia, Spain
| | - Araceli García-Martínez
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
| | - Elena Dios
- Unidad de Gestión de Endocrinología y Nutrición. Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - Mari C Vázquez-Borrego
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain
| | - Pablo Remón-Ruiz
- Unidad de Gestión de Endocrinología y Nutrición. Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - Rosa Cámara
- Department of Endocrinology and Nutrition, Polytechnic University Hospital La Fe, 46026, Valencia, Spain
| | - Cristina Lamas
- Department of Endocrinology and Nutrition, Albacete University Hospital, 02006, Albacete, Spain
| | - José Carlos Padillo-Cuenca
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Service of Endocrinology and Nutrition, IMIBIC, HURS, 14004 Cordoba, Spain
| | | | - David A Cano
- Unidad de Gestión de Endocrinología y Nutrición. Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - Manuel D Gahete
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain
| | - Aura D Herrera-Martínez
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Service of Endocrinology and Nutrition, IMIBIC, HURS, 14004 Cordoba, Spain
| | - Antonio Picó
- Department of Endocrinology and Nutrition, Alicante General University Hospital. Institute for Health and Biomedical Research (ISABIAL). University Miguel Hernandez, CIBER Rare Diseases, 03010, Alicante, Spain
| | - Alfonso Soto-Moreno
- Unidad de Gestión de Endocrinología y Nutrición. Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - María Ángeles Gálvez-Moreno
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Service of Endocrinology and Nutrition, IMIBIC, HURS, 14004 Cordoba, Spain
| | - Justo P Castaño
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain
| | - Raúl M Luque
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), 14004 Cordoba, Spain
- Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain
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Treppiedi D, Di Muro G, Mangili F, Catalano R, Giardino E, Barbieri AM, Locatelli M, Arosio M, Spada A, Peverelli E, Mantovani G. Filamin A is required for somatostatin receptor type 5 expression and pasireotide-mediated signaling in pituitary corticotroph tumor cells. Mol Cell Endocrinol 2021; 524:111159. [PMID: 33428965 DOI: 10.1016/j.mce.2021.111159] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 12/16/2020] [Accepted: 01/03/2021] [Indexed: 01/08/2023]
Abstract
Somatostatin receptor type 5 (SST5) represents the main pharmacological target in the treatment of adrenocorticotroph hormone (ACTH)-secreting tumors. However, molecular predictors of responsiveness to pasireotide require further investigation. The cytoskeleton protein filamin A (FLNA) modulates the responsiveness to somatostatin analogs (SSA) treatment in other types of pituitary tumors by regulating somatostatin receptor type 2 (SST2)/dopamine receptor type 2 (DRD2) expression and activity. Here, we aimed to test the involvement of FLNA in the modulation of SST5 response to SSA in human and murine tumor corticotrophs. Western blot analysis of human corticotropinomas showed that FLNA and SST5 correlate. Both in human primary cultures and AtT-20 cells, FLNA genetic silencing caused a decrease of receptor expression level. Moreover, pasireotide-mediated SST5 downregulation observed in AtT-20 control cells was no further detected in FLNA silenced cells. In AtT-20 cells, in situ PLA experiments revealed an increased number of SST5-FLNA complexes following pasireotide incubation. Finally, FLNA knock down abolished pasireotide-induced SST5 actions on hormone secretion, cell proliferation and apoptosis. In conclusion, FLNA is implicated in SST5 expression modulation and signaling.
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Affiliation(s)
- Donatella Treppiedi
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Genesio Di Muro
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Federica Mangili
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Rosa Catalano
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy; PhD Program in Endocrinological Sciences, Sapienza University of Rome, Rome, Italy
| | - Elena Giardino
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Anna Maria Barbieri
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Marco Locatelli
- Department of Pathophysiology and Transplantation, University of Milan, Italy; Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurosurgery Unit, Milan, Italy
| | - Maura Arosio
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy; Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrinology Unit, Milan, Italy
| | - Anna Spada
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Erika Peverelli
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
| | - Giovanna Mantovani
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy; Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrinology Unit, Milan, Italy
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Kageyama K, Hagiwara R, Niioka K, Takayasu S, Daimon M. Differential effects of β-arrestin1 and β-arrestin2 on somatostatin receptors in murine AtT-20 corticotroph tumor cells. Endocr J 2021; 68:163-170. [PMID: 32963176 DOI: 10.1507/endocrj.ej20-0251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Autonomous production of adrenocorticotropic hormone (ACTH) from pituitary corticotroph adenomas is the primary cause of Cushing's disease. Somatostatin receptor, a G protein-coupled receptor (GPCR), types 2 (SSTR2) and 5 (SSTR5) mRNA expression is greater than that of other SSTR subtypes in human corticotroph adenomas. Further, the multiligand SOM230 shows potent effects in decreasing ACTH plasma levels and urinary free cortisol levels in patients with Cushing's disease. We previously showed that both Sstr2 and Sstr5 mRNA levels were unaffected by SOM230 treatment, suggesting that both receptors might not be downregulated by the agonist. Intracellular molecules, such as β-arrestins, modulate ligand activated-receptor responses. In the present study, we determined regulation of β-arrestin1 and β-arrestin2 by SOM230 and dexamethasone in murine AtT-20 corticotroph tumor cells. In addition, we examined the effects of β-arrestin1 and β-arrestin2 on Sstr mRNA and their protein levels. SOM230 treatment increased β-arrestin1 mRNA levels and did not alter β-arrestin2 mRNA levels. SOM230 treatment could induce β-arrestin1 production in corticotroph tumor cells. Dexamethasone treatment decreased β-arrestin2 mRNA levels. β-arrestin2 knockdown increased proopiomelanocortin, and both Sstr2 and Sstr5 mRNA and their protein levels. The β-arrestin2 knockdown-increased proopiomelanocortin mRNA levels were canceled by SOM230 treatment.
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Affiliation(s)
- Kazunori Kageyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Rie Hagiwara
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kanako Niioka
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Shinobu Takayasu
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
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De Ravin E, Phan HAT, Harmsen S, Cho SS, Teng CW, Petersson EJ, White C, Galban EM, Hess R, Lee JYK. Somatostatin Receptor as a Molecular Imaging Target in Human and Canine Cushing Disease. World Neurosurg 2021; 149:94-102. [PMID: 33601082 DOI: 10.1016/j.wneu.2021.02.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Fluorescence-guided surgery may improve completeness of resection in transsphenoidal surgery for Cushing disease (CD) by enabling visualization of residual tumor tissue at the margins. In this review we discuss somatostatin receptors (SSTRs) as targets for fluorescence-guided surgery and overview existing SSTR-specific imaging agents. We also compare SSTR expression in normal pituitary and corticotrophinoma tissues from human and canine CD patients to assess canines as a translational model for CD. METHODS A PubMed literature search was conducted for publications containing the terms canine, somatostatin receptor, Cushing's disease, and corticotroph adenoma. SSTR expression data from each study was documented as the presence or absence of expression or, when possible, the number of tumors expressing a given SSTR subtype within a group of tumors being studied. Studies that used reverse transcription polymerase chain reaction to quantify SSTR expression were selected for additional comparative analysis. RESULTS SSTR5 is strongly expressed in human corticotroph adenomas and weakly expressed in surrounding pituitary parenchyma, a pattern not conclusively observed in canine patients. SSTR2 mRNA expression is similar in human normal pituitary and corticotrophinoma cells but may be significantly higher in canine normal pituitary tissue than in corticotroph tumoral tissue. Limited data were available on SSTR subtypes 1, 3, and 4. CONCLUSIONS Further studies must fill the knowledge gaps related to species-specific SSTR expression, so using canine CD as a translational model may be premature. We do conclude that the expression profile of SSTR5 (i.e., high local expression in pituitary adenomas relative to normal surrounding tissues) makes SSTR5 a promising molecular target for FGS.
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Affiliation(s)
- Emma De Ravin
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hoang Anh T Phan
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stefan Harmsen
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steve S Cho
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Clare W Teng
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - E James Petersson
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Caitlin White
- Department of Endocrinology at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Evelyn M Galban
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rebecka Hess
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - John Y K Lee
- Department of Neurosurgery at the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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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.
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Treppiedi D, Giardino E, Catalano R, Mangili F, Vercesi P, Sala E, Locatelli M, Arosio M, Spada A, Mantovani G, Peverelli E. Somatostatin analogs regulate tumor corticotrophs growth by reducing ERK1/2 activity. Mol Cell Endocrinol 2019; 483:31-38. [PMID: 30611770 DOI: 10.1016/j.mce.2018.12.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 12/11/2018] [Accepted: 12/31/2018] [Indexed: 12/31/2022]
Abstract
Pasireotide has been associated with tumor shrinkage in patients with Cushing's disease subjected to long term treatment. However, to date the implicated molecular mechanisms are poorly elucidated. Here, we tested pasireotide-mediated cytostatic and cytotoxic effects in ACTH-secreting primary tumor cultures and murine corticotroph tumor cell line, AtT-20 cells. We found somatostatin receptor type 5 (SST5) expressed in 17 different ACTH-secreting tumors and SST2 detectable in 15 out of the 17 tissues. Pasireotide caused a slight but significant in vitro inhibition of cell growth in 3 out of 6 ACTH-secreting primary cultures (-12.1 ± 4.3%, P < 0.01 at 10 nM), remarkably reduced phospho-ERK1/2 levels in 5 out of 8 samples (-36.4 ± 20.5%, P < 0.01 at 1 μM) and triggered an increase of caspase 3/7 activity in 2 of 4 tumors (17 ± 3.6%, P < 0.05 at 1 μM). Accordingly, in AtT-20 cells, pasireotide significantly inhibited cell proliferation (-10.5 ± 7.7% at 10 nM, P < 0.05; -13.9 ± 10.9% at 100 nM, P < 0.05; -26.8 ± 8.9% at 1 μM, P < 0.01). Similar antiproliferative actions were exerted by BIM23206 and BIM23120 (SST5&2 selective ligands, respectively), whereas octreotide was effective when used at 1 μM (-13.3 ± 9.1%, P < 0.05). Moreover, a reduction of phospho-ERK1/2 was observed upon pasireotide and BIM23206 treatment (-8.4 ± 28.6%, P < 0.01 and -51.4 ± 15.9%, P < 0.001 at 10 nM, respectively) but not after octreotide and BIM23120 incubation. Finally, pasireotide was able to induce cell apoptosis in AtT-20 cells at lower concentration than octreotide. Altogether these data indicate a downstream implication of SST5-mediated phospho-ERK1/2 inhibition by pasireotide resulting in ACTH-secreting tumor cells proliferation reduction. Moreover, we describe for the first time a pro-apoptotic effect of pasireotide in corticotrophs.
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Affiliation(s)
- Donatella Treppiedi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Elena Giardino
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Rosa Catalano
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy; PhD Program in Endocrinological Sciences, Sapienza University of Rome, Rome, Italy
| | - Federica Mangili
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Pietro Vercesi
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Elisa Sala
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Marco Locatelli
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurosurgery Unit, Milan, Italy
| | - Maura Arosio
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Anna Spada
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Giovanna Mantovani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
| | - Erika Peverelli
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Endocrine Unit, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
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Frank N, Hermida P, Sanchez-Londoño A, Singh R, Gradil CM, Uricchio CK. Blood Glucose and Insulin Concentrations after Octreotide Administration in Horses With Insulin Dysregulation. J Vet Intern Med 2017; 31:1188-1192. [PMID: 28503791 PMCID: PMC5508354 DOI: 10.1111/jvim.14718] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 01/16/2017] [Accepted: 03/22/2017] [Indexed: 02/02/2023] Open
Abstract
Background Octreotide is a somatostatin analog that suppresses insulin secretion. Hypothesis We hypothesized that octreotide would suppress insulin concentrations in horses and that normal (N) horses and those with insulin dysregulation (ID) would differ significantly in their plasma glucose and insulin responses to administration of octreotide. Animals Twelve horses, N = 5, ID = 7. Methods Prospective study. An oral sugar test was performed to assign horses to N and ID groups. Octreotide (1.0 μg/kg IV) was then administered, and blood was collected at 0, 5, 10, 15, 20, 25, 30, 45, 60, 75, and 90 minute, and 2, 3, 4, 6, 8, 12, and 24 hour for measurement of glucose and insulin concentrations. Area under the curve (AUC) values were calculated. Results Mean AUC values for glucose and insulin did not differ between normal (n = 5) and ID (n = 7) groups after octreotide injection. Significant time (P < .001) effects were detected for glucose and insulin concentrations. A group × time interaction (P = .091) was detected for insulin concentrations after administration of octreotide, but the group (P = .33) effect was not significant. Conclusions and Clinical Importance Octreotide suppresses insulin secretion, resulting in hyperglycemia, and then concentrations increase above baseline as glycemic control is restored. Our hypothesis that octreotide causes insulin concentrations to decrease in horses was supported, but differences between N and ID groups did not reach statistical significance when blood glucose and insulin responses were compared. The utility of an octreotide response test remains to be determined.
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Affiliation(s)
- N Frank
- Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA
| | - P Hermida
- Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA
| | - A Sanchez-Londoño
- Department of Environmental and Population Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA
| | - R Singh
- Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA
| | - C M Gradil
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA
| | - C K Uricchio
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA
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Mandanas S, Mathiopoulou L, Boudina M, Chrisoulidou A, Pazaitou-Panayiotou K. Loss of Efficacy of Pasireotide After its Re-Administration: is There a Reason Why? Rare Tumors 2016; 8:6489. [PMID: 28191290 PMCID: PMC5226048 DOI: 10.4081/rt.2016.6489] [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] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 09/21/2016] [Accepted: 09/29/2016] [Indexed: 12/04/2022] Open
Abstract
Pasireotide is a recently approved medical treatment for persistent or recurrent Cushing's disease (CD). However, an escape from the initial successful response has not yet been described. A 42-year-old female presented with several symptoms indicative of hypercortisolism. Biochemical evaluation and imaging were consistent with CD due to a pituitary adenoma. Surgical excision of the adenoma was unsuccessful and gamma-knife radiosurgery was followed. Our patient remained hypercortisolemic thus treatment with pasireotide (900 mg subcutaneously twice daily) was decided. Biochemical and clinical remission was noted shortly thereafter. Moderate adverse events led to dose reduction to 600 mg subcutaneously twice daily. The patient remained in remission for 6 months, when treatment was discontinued due to cholecystitis. One month after cholecystectomy, pasireotide was restarted with no clinical or biochemical benefit that time. Pasireotide is an effective medical treatment for CD. Nevertheless, a loss of its initial efficacy may rarely be described.
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10
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Sugiyama A, Kageyama K, Murasawa S, Ishigame N, Niioka K, Daimon M. Inhibition of heat shock protein 90 decreases ACTH production and cell proliferation in AtT-20 cells. Pituitary 2015; 18:542-53. [PMID: 25280813 DOI: 10.1007/s11102-014-0607-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE Cushing's disease is primarily caused by adrenocorticotropic hormone (ACTH)-producing pituitary adenomas. If excision of the tumor from the pituitary, which is the primary treatment for Cushing's disease, is unsuccessful, further medical therapy is needed to treat the resultant hypercortisolism. Some of the drugs used to treat this condition have shown potential therapeutic benefits, but a more effective treatment should be explored for the treatment of Cushing's disease. In the present study, we determined the effect of heat shock protein 90 inhibitors on ACTH production and cell proliferation of AtT-20 corticotroph tumor cells. METHODS AtT-20 pituitary corticotroph tumor cells were cultured. The expression levels of mouse proopiomelanocortin (POMC) and pituitary tumor transforming gene 1 (PTTG1) mRNA were evaluated using quantitative real-time PCR. Cellular DNA content was analyzed with fluorescence-activated cell sorting (FACS) analysis. The protein levels were determined by Western blot analysis. RESULTS Both 17-allylamino-17-demethoxygeldanamycin and CCT018159 decreased POMC mRNA levels in AtT-20 cells and ACTH levels in the culture medium of these cells, suggesting that both drugs suppress ACTH synthesis and secretion in corticotroph tumor cells. Both drugs also decreased cell proliferation and induced apoptosis. FACS analyses revealed that both agents increased the percentage of AtT-20 cells in the G2/M phase. These drugs decreased cell proliferation, presumably due to the induction of cell death and arrest of the cell cycle in AtT-20 cells. Tumor weight in mice xenografted with AtT-20 cells and treated with CCT018159 was lower than in AtT-20-xenografted control mice. CCT018159 also decreased plasma ACTH levels, and POMC and PTTG1 mRNA levels in the tumor cells. CONCLUSIONS CCT018159 inhibits ACTH production and corticotroph tumor cell proliferation in vitro and in vivo.
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Affiliation(s)
- Aya Sugiyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
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11
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Ferrau F, Trimarchi F, Cannavo S. Adrenocorticotropin responsiveness to acute octreotide administration is not affected by mifepristone premedication in patients with Cushing's disease. Endocrine 2014; 47:550-6. [PMID: 24408052 DOI: 10.1007/s12020-013-0163-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 12/30/2013] [Indexed: 01/27/2023]
Abstract
Octreotide (OCT) is ineffective in patients with Cushing's disease (CD) due to the cortisol-induced down-regulation of somatostatin receptor subtype 2 which was shown to be reversible in vitro by using anti-glucocorticoid mifepristone. This study aimed to verify, in vivo, if mifepristone can modulate response to acute OCT administration in patients with CD. Three men and two postmenopausal women (age 52.5 ± 2 years) with CD were enrolled in the study. OCT (100 μg, s.c.) was administered alone on the first day (OCT-only), and it was then given after mifepristone administration (2 × 200 mg, p.os, 12 and 1 h before OCT), 3 days later (OCT-mif). ACTH and cortisol levels were measured before OCT administration and every 60 min thereafter for 6 h. Baseline ACTH and cortisol values, nadir values and percentage decrements (Δn) were compared during both tests. Mean ACTH-Δn did not differ significantly during the two tests. Both tests induced a <30 % decrease in plasma ACTH in three patients (#1, 2 and 3) and a >50 % decrease in the other two cases (#4 and 5). Cortisol decreased in patients #4 and 5, during both tests. ACTH-Δn did not correlate with morning cortisol nor with urinary free cortisol values. Patients #4 and 5 with the highest ACTH-Δn had the lowest cortisol values after 1 mg of dexamethasone. Brief mifepristone pre-treatment does not modify ACTH and cortisol response to acute OCT administration in CD. However, OCT seems to be more effective in patients with partially preserved cortisol inhibitory feedback.
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Affiliation(s)
- Francesco Ferrau
- Department of Clinical and Experimental Medicine, University of Messina, AOU Policlinico "G. Martino" (Pad. H, 4th Floor), Via Consolare Valeria 1, 98125, Messina, Italy,
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12
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Murasawa S, Kageyama K, Sugiyama A, Ishigame N, Niioka K, Suda T, Daimon M. Inhibitory effects of SOM230 on adrenocorticotropic hormone production and corticotroph tumor cell proliferation in vitro and in vivo. Mol Cell Endocrinol 2014; 394:37-46. [PMID: 25011056 DOI: 10.1016/j.mce.2014.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 06/22/2014] [Accepted: 07/01/2014] [Indexed: 11/30/2022]
Abstract
Adrenocorticotropic hormone (ACTH) production by pituitary corticotroph adenomas is the main cause of Cushing's disease. A drug that targets pituitary ACTH-secreting adenomas would aid treatment of Cushing's disease. Octreotide, a somatostatin receptor type 2 (SSTR2)-preferring somatostatin analogue, has no effect on ACTH secretion in patients with Cushing's disease. The multiligand SOM230 (pasireotide) displays a much higher affinity for SSTR1 and SSTR5 than octreotide and suppresses ACTH secretion in cultures of human corticotroph tumors to a greater extent than octreotide. In the present in vitro and in vivo study, we determined the effect of SOM230 on ACTH production and cell proliferation of AtT-20 corticotroph tumor cells. SOM230 decreased proopiomelanocortin (POMC) mRNA levels in AtT-20 cells and ACTH levels in the culture medium of these cells, suggesting that SOM230 suppresses ACTH synthesis and secretion in corticotroph tumor cells. SOM230 also decreased cell proliferation and both cyclic adenosine monophosphate response element-binding protein and Akt phosphorylation in AtT-20 cells. SSTR5 knockdown inhibited the SOM230-induced decreases in cell proliferation. Fluorescence-activated cell sorting analyses revealed that SOM230 did not attenuate cell cycle progression. Tumor weight in mice xenografted with AtT-20 cells and treated with SOM230 was significantly lower than in AtT-20-xenografted control mice. SOM230 also significantly decreased plasma ACTH levels, and POMC and pituitary tumor transforming gene mRNA levels in the tumor cells. Thus, SOM230 inhibits ACTH production and corticotroph tumor cell proliferation in vitro and in vivo.
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Affiliation(s)
- Shingo Murasawa
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kazunori Kageyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan; Department of Endocrinology, Metabolism, and Infectious Diseases, Hirosaki University School of Medicine & Hospital, 53 Hon-cho, Hirosaki, Aomori 036-8563, Japan.
| | - Aya Sugiyama
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Noriko Ishigame
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Kanako Niioka
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Toshihiro Suda
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
| | - Makoto Daimon
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori 036-8562, Japan
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Abstract
The somatostatin (SRIF) system, which includes the SRIF ligand and receptors, regulates anterior pituitary gland function, mainly inhibiting hormone secretion and to some extent pituitary tumor cell growth. SRIF-14 via its cognate G-protein-coupled receptors (subtypes 1-5) activates multiple cellular signaling pathways including adenylate cyclase/cAMP, MAPK, ion channel-dependent pathways, and others. In addition, recent data have suggested SRIF-independent constitutive SRIF receptor activity responsible for GH and ACTH inhibition in vitro. This review summarizes current knowledge on ligand-dependent and independent SRIF receptor molecular and functional effects on hormone-secreting cells in the anterior pituitary gland.
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Affiliation(s)
- Tamar Eigler
- Division of EndocrinologyDiabetes and Metabolism, Department of Medicine, Pituitary Center, Cedars Sinai Medical Center, Davis Building, Room 3066, 8700 Beverly Boulevard, Los Angeles, California 90048, USA
| | - Anat Ben-Shlomo
- Division of EndocrinologyDiabetes and Metabolism, Department of Medicine, Pituitary Center, Cedars Sinai Medical Center, Davis Building, Room 3066, 8700 Beverly Boulevard, Los Angeles, California 90048, USA
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Peineau S, Guimiot F, Csaba Z, Jacquier S, Fafouri A, Schwendimann L, de Roux N, Schulz S, Gressens P, Auvin S, Dournaud P. Somatostatin receptors type 2 and 5 expression and localization during human pituitary development. Endocrinology 2014; 155:33-9. [PMID: 24189142 DOI: 10.1210/en.2013-1683] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Somatostatin (SRIF), by acting mainly through sst2 and sst5 receptors, is a potent inhibitor of hormonal secretion by the human anterior pituitary gland. However, the pattern of protein expression of these SRIF receptors remains unknown during pituitary development. To get further insights into the physiological role of SRIF receptors in human development and pituitary function, the present study examined the developmental expression of the sst2 and sst5 receptors in the individual cell types of the anterior human pituitary. Thirteen fetal human pituitaries were investigated between 13 to 38 weeks of gestation (WG) by double-labeling immunofluorescence with antibodies raised against sst2 or sst5 receptors and GH, LH, FSH, TSH, or pro-opiomelanocortin proteins. SRIF immunoreactivity in the hypothalamus and median eminence was investigated at the same developmental ages. Immunoreactivity for the sst2 receptor was evident as early as 13 to 15 WG and onward mainly in TSH-, LH-, and FSH-expressing cells, whereas sst5 immunoreactivity was apparent at the late development stages (35-38 WG). GH-expressing cells mainly expressed sst5 immunoreactivity. SRIF-positive fibers and cells were detected as soon as 13 to 16 WG in the hypothalamus and median eminence and their densities increased with gestational age. The early appearance of hypothalamic SRIF cells and fibers suggests a physiological link between SRIF and its receptors during pituitary development. Whereas sst2 receptors might play a primary role in the differentiation and regulation of TSH, LH, and FSH cells, sst5 receptors appear to be mainly involved in GH regulation from birth onward.
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Affiliation(s)
- Stéphane Peineau
- Medical Research Council Centre for Synaptic Plasticity (S.P.), University of Bristol, School of Physiology and Pharmacology, Bristol BS8 1TD, United Kingdom; Inserm (S.P., F.G., Z.C., S.J., A.F., L.S., N.d.R., P.G., S.A., P.D.), U676, 75019 Paris, France; University Paris Diderot (S.P., F.G., Z.C., S.J., A.F., L.S., N.d.R., P.G., S.A., P.D.), Sorbonne Paris Cité, UMR676, 75019 Paris, France; and Institute of Pharmacology and Toxicology (S.S.), Jena University Hospital, Friedrich Schiller University Jena, Germany
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15
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Reubi JC, Schonbrunn A. Illuminating somatostatin analog action at neuroendocrine tumor receptors. Trends Pharmacol Sci 2013; 34:676-88. [PMID: 24183675 DOI: 10.1016/j.tips.2013.10.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/26/2013] [Accepted: 10/03/2013] [Indexed: 02/08/2023]
Abstract
Somatostatin analogs for the diagnosis and therapy of neuroendocrine tumors (NETs) have been used in clinical applications for more than two decades. Five somatostatin receptor subtypes have been identified and molecular mechanisms of somatostatin receptor signaling and regulation have been elucidated. These advances increased understanding of the biological role of each somatostatin receptor subtype, their distribution in NETs, as well as agonist-specific regulation of receptor signaling, internalization, and phosphorylation, particularly for the sst2 receptor subtype, which is the primary target of current somatostatin analog therapy for NETs. Various hypotheses exist to explain differences in patient responsiveness to somatostatin analog inhibition of tumor secretion and growth as well as differences in the development of tumor resistance to therapy. In addition, we now have a better understanding of the action of both first generation (octreotide, lanreotide, Octreoscan) and second generation (pasireotide) FDA-approved somatostatin analogs, including the biased agonistic character of some agonists. The increased understanding of somatostatin receptor pharmacology provides new opportunities to design more sophisticated assays to aid the future development of somatostatin analogs with increased efficacy.
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Affiliation(s)
- Jean Claude Reubi
- Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, Berne, Switzerland.
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16
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Chemometric evaluation of urinary steroid hormone levels as potential biomarkers of neuroendocrine tumors. Molecules 2013; 18:12857-76. [PMID: 24135941 PMCID: PMC6269673 DOI: 10.3390/molecules181012857] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/25/2013] [Accepted: 10/10/2013] [Indexed: 01/08/2023] Open
Abstract
Neuroendocrine tumors (NETs) are uncommon tumors which can secrete specific hormone products such as peptides, biogenic amines and hormones. So far, the diagnosis of NETs has been difficult because most NET markers are not specific for a given tumor and none of the NET markers can be used to fulfil the criteria of high specificity and high sensitivity for the screening procedure. However, by combining the measurements of different NET markers, they become highly sensitive and specific diagnostic tests. The aim of the work was to identify whether urinary steroid hormones can be identified as potential new biomarkers of NETs, which could be used as prognostic and clinical course monitoring factors. Thus, a rapid and sensitive reversed-phase high-performance liquid chromatographic method (RP-HPLC) with UV detection has been developed for the determination of cortisol, cortisone, corticosterone, testosterone, epitestosterone and progesterone in human urine. The method has been validated for accuracy, precision, selectivity, linearity, recovery and stability. The limits of detection and quantification were 0.5 and 1 ng mL−1 for each steroid hormone, respectively. Linearity was confirmed within a range of 1–300 ng mL−1 with a correlation coefficient greater than 0.9995 for all analytes. The described method was successfully applied for the quantification of six endogenous steroid levels in human urine. Studies were performed on 20 healthy volunteers and 19 patients with NETs. Next, for better understanding of tumor biology in NETs and for checking whether steroid hormones can be used as potential biomarkers of NETs, a chemometric analysis of urinary steroid hormone levels in both data sets was performed.
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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.
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Affiliation(s)
- Maria Fleseriu
- Departments of Medicine and Neurological Surgery, and Northwest Pituitary Center, Oregon Health & Science University, Portland, OR 97239, USA.
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18
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Colao A, Simeoli C, De Leo M, Cozzolino A, Pivonello R. Pasireotide for the treatment of Cushing's disease. Expert Opin Orphan Drugs 2013. [DOI: 10.1517/21678707.2013.807731] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Ding Y, Fan J, Li W, Yang R, Peng Y, Deng L, Wu Y, Fu Q. The effect of albumin fusion patterns on the production and bioactivity of the somatostatin-14 fusion protein in Pichia pastoris. Appl Biochem Biotechnol 2013; 170:1637-48. [PMID: 23712794 DOI: 10.1007/s12010-013-0304-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 05/14/2013] [Indexed: 10/26/2022]
Abstract
Somatostatin is a natural inhibitor of growth hormone, and its analogues are clinically used for the therapy of acromegaly, gigantism, thyrotropinoma, and other carcinoid syndrome. However, natural somatostatin is limited for clinical usage because of its short half-life in vivo. Albumin fusion technology was used to construct long-acting fusion proteins, and Pichia pastoris was used as an expression system. Three fusion proteins, (somatostatin (SS)14)2-human serum albumin (HSA), (SS14)3-HSA, and HSA-(SS14)3, were constructed with different fusion copies of somatostatin-14 and fusion orientations. The expression level of (SS14)3-HSA and HSA-(SS14)3 was much lower than (SS14)2-HSA due to the additional fusion of the somatostatin-14 molecule. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry revealed that severe degradation occurred in the fermentation process. Similar to the standard of somatostatin-14, all three fusion proteins were able to inhibit growth hormone secretion in the blood, with (SS14)2-HSA being the most effective one. On the whole, (SS14)2-HSA was the most effective protein in both production level and bioactivity, and increasing the number of small protein copies fused to HSA may not be a suitable method to improve the protein bioactivity.
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Affiliation(s)
- Yuedi Ding
- Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, QianRong Road No. 20, Wuxi, Jiangsu 214063, China
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20
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Sowiński J, Sawicka N, Piątek K, Zybek A, Ruchała M. Pharmacoeconomic aspects of the treatment of pituitary gland tumours. Contemp Oncol (Pozn) 2013; 17:137-43. [PMID: 23788980 PMCID: PMC3685378 DOI: 10.5114/wo.2013.34616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 04/14/2013] [Accepted: 04/18/2013] [Indexed: 12/17/2022] Open
Abstract
Nowadays physicians are under economic pressure; therefore therapeutic decisions based on safety, efficacy, and the effectiveness of the medication also require economic analysis. The aim of this review is to discuss data concerning the cost-effectiveness of drug therapy in patients with hormonally active pituitary adenomas, namely growth hormone, adrenocorticotropic hormone, thyroid-stimulating hormone-secreting pituitary adenomas, prolactinoma and pituitary incidentaloma. In acromegalic patients using lanreotide is cheaper for health care payers and more convenient for physicians and patients because of the opportunity for self/partner injections, lower clogging risk and possibility of longer intervals between injections, while the efficacy is comparable with octreotide. Patients with prolactinomas should be treated with novel dopamine agonists, such as cabergoline or quinagolide, however, bromocriptine still remains a cheaper and almost as effective alternative. There are no easy methods or algorithms, but in general, extracting the maximum value from the investment in treatment is essential.
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Affiliation(s)
- Jerzy Sowiński
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Poland
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21
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Kwan DHT, Yung LY, Ye RD, Wong YH. Activation of Ras-dependent signaling pathways by G(14) -coupled receptors requires the adaptor protein TPR1. J Cell Biochem 2013; 113:3486-97. [PMID: 22711498 DOI: 10.1002/jcb.24225] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Many G(q) -coupled receptors mediate mitogenic signals by stimulating extracellular signal-regulated protein kinases (ERKs) that are typically regulated by the small GTPase Ras. Recent studies have revealed that members of the Gα(q) family may possess the ability to activate Ras/ERK by interacting with the adaptor protein tetratricopeptide repeat 1 (TPR1). Within the Gα(q) family, the highly promiscuous Gα(14) can relay signals from numerous receptors. Here, we examined if Gα(14) interacts with TPR1 to stimulate Ras signaling pathways. Expression of the constitutively active Gα(14) QL mutant in HEK293 cells led to the formation of GTP-bound Ras as well as increased phosphorylations of downstream signaling molecules including ERK and IκB kinase. Stimulation of endogenous G(14) -coupled somatostatin type 2 and α(2) -adrenergic receptors produced similar responses in human hepatocellular HepG2 carcinoma cells. Co-immunoprecipitation assays using HEK293 cells demonstrated a stronger association of TPR1 for Gα(14) QL than Gα(14) , suggesting that TPR1 preferentially binds to the GTP-bound form of Gα(14) . Activated Gα(14) also interacted with the Ras guanine nucleotide exchange factors SOS1 and SOS2. Expression of a dominant negative mutant of TPR1 or siRNA-mediated knockdown of TPR1 effectively abolished the ability of Gα(14) to induce Ras signaling in native HepG2 or transfected HEK293 cells. Although expression of the dominant negative mutant of TPR1 suppressed Gα(14) QL-induced phosphorylations of ERK and IκB kinase, it did not affect Gα(14) QL-induced stimulation of phospholipase Cβ or c-Jun N-terminal kinase. Our results suggest that TPR1 is required for Gα(14) to stimulate Ras-dependent signaling pathways, but not for the propagation of signals along Ras-independent pathways.
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Affiliation(s)
- Dawna H T Kwan
- Division of Life Science and the Biotechnology Research Institute, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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Nuevas perspectivas en el tratamiento farmacológico de la enfermedad de Cushing. ACTA ACUST UNITED AC 2012; 59:599-605. [DOI: 10.1016/j.endonu.2012.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/18/2012] [Accepted: 07/20/2012] [Indexed: 11/18/2022]
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Moloney KJ, Mercado JU, Ludlam WH, Mayberg MR. Pasireotide (SOM230): a novel pituitary-targeted medical therapy for the treatment of patients with Cushing's disease. Expert Rev Endocrinol Metab 2012; 7:491-502. [PMID: 30780888 DOI: 10.1586/eem.12.49] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cushing's disease (CD) is a rare and debilitating condition resulting from extended exposure to excessive glucocorticoids caused by an adrenocorticotropic hormone-secreting pituitary adenoma. First-line treatment for most patients with CD is trans-sphenoidal adenomectomy. Postsurgical remission remains problematic; however, due to the difficulty of removing the tumor. Until recently, there were no approved medical treatments for Cushing's syndrome, but recent data on pasireotide (SOM230; a novel somatostatin analog) demonstrate restored hormone levels and improvements in quality of life, with a safety profile similar to that of other somatostatin analogs, except for incidence of hyperglycemia. Pasireotide represents an exciting, novel, pituitary-targeted medical therapy for patients with CD who are not surgical candidates, or for those who experience postsurgical recurrence.
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Affiliation(s)
- Kelley J Moloney
- a Seattle Pituitary Center, Swedish Neuroscience Institute, Seattle, WA, USA
- c Seattle Pituitary Center, Swedish Neuroscience Institute, Seattle, WA, USA.
| | - Jennifer U Mercado
- a Seattle Pituitary Center, Swedish Neuroscience Institute, Seattle, WA, USA
| | | | - Marc R Mayberg
- a Seattle Pituitary Center, Swedish Neuroscience Institute, Seattle, WA, USA
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Somvanshi RK, Kumar U. Pathophysiology of GPCR Homo- and Heterodimerization: Special Emphasis on Somatostatin Receptors. Pharmaceuticals (Basel) 2012; 5:417-46. [PMID: 24281555 PMCID: PMC3763651 DOI: 10.3390/ph5050417] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 04/18/2012] [Accepted: 04/19/2012] [Indexed: 12/19/2022] Open
Abstract
G-protein coupled receptors (GPCRs) are cell surface proteins responsible for translating >80% of extracellular reception to intracellular signals. The extracellular information in the form of neurotransmitters, peptides, ions, odorants etc is converted to intracellular signals via a wide variety of effector molecules activating distinct downstream signaling pathways. All GPCRs share common structural features including an extracellular N-terminal, seven-transmembrane domains (TMs) linked by extracellular/intracellular loops and the C-terminal tail. Recent studies have shown that most GPCRs function as dimers (homo- and/or heterodimers) or even higher order of oligomers. Protein-protein interaction among GPCRs and other receptor proteins play a critical role in the modulation of receptor pharmacology and functions. Although ~50% of the current drugs available in the market target GPCRs, still many GPCRs remain unexplored as potential therapeutic targets, opening immense possibility to discover the role of GPCRs in pathophysiological conditions. This review explores the existing information and future possibilities of GPCRs as tools in clinical pharmacology and is specifically focused for the role of somatostatin receptors (SSTRs) in pathophysiology of diseases and as the potential candidate for drug discovery.
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Affiliation(s)
- Rishi K Somvanshi
- Faculty of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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25
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Briet C, Chanson P. [Pituitary disease: which treatment in the future?]. ANNALES D'ENDOCRINOLOGIE 2011; 72 Suppl 1:S2-7. [PMID: 22008273 DOI: 10.1016/s0003-4266(11)70003-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Even if major progress has been made in the medical treatment for pituitary adenomas in the last decades, currently available drugs do not always control hormonal secretion of these tumors. New molecules or new formulations of old drugs are under development. Pituitary stem cells research is currently also very active.
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Affiliation(s)
- C Briet
- INSERM U 986, Hôpital Saint-Vincent-de-Paul, 82 avenue Denfert-Rochereau, Paris, France
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Mariniello B, Finco I, Sartorato P, Patalano A, Iacobone M, Guzzardo V, Fassina A, Mantero F. Somatostatin receptor expression in adrenocortical tumors and effect of a new somatostatin analog SOM230 on hormone secretion in vitro and in ex vivo adrenal cells. J Endocrinol Invest 2011; 34:e131-8. [PMID: 21042045 DOI: 10.1007/bf03346721] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
BACKGROUND Somatostatin is a widely distributed polypeptide that modulates endocrine and exocrine secretion, cell proliferation, and apoptosis by 5 somatostatin receptors (SSTR1-5). The inhibitory effects of somatostatin on tumor growth may be the result of its suppressing the synthesis and/or secretion of growth factors and growth-promoting hormones. AIM Very little information is available on the effect of somatostatin analogs on adrenal tumors, so we examined SSTR expression in adrenocortical tumors and studied the effect of a somatostatin analog (SOM230) on hormone secretion and cell viability in adrenal cells. MATERIAL/SUBJECTS AND METHODS SSTR expression was analyzed by real-time PCR in 13 adrenocortical carcinomas (ACC), 24 aldosterone-producing adenomas (APA), 11 cortisol-producing adenomas (CPA), and 7 normal adrenals (NA), and verified by immunohistochemistry (IHC) in 14 samples. The effect of SOM230 on cortisol or aldosterone secretion in H295R and primary cell cultures was determined by radioimmunoassay, and its effect on viability in H295R and SW13 using the MTT test. RESULTS SSTR1 and SSTR2 mRNA was expressed in 100% of adrenal tumors. Compared to NA, ACC revealed an increase in almost all SSTR, while only some APA over-expressed SSTR3 and SSTR1. CPA expressed SSTR similar to NA. IHC confirmed the mRNA expression data. At nanomolar concentrations, SOM230 inhibited hormone secretion in primary adrenal cultures and H295R cells, but had no evident effect on cell viability. CONCLUSIONS The evidence of SSTR over-expression (particularly in ACC) and of hormone secretion being inhibited by SOM230 suggests a potential therapeutic role for this broad-spectrum somatostatin analog in adrenal tumors.
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Affiliation(s)
- B Mariniello
- Endocrinology Division, University of Padua, Via Ospedale 105, 35128 Padua, Italy.
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27
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Liu JM, Gu LQ, Zhao L, Tang ZY, Sun LH, Hong J, Wang WQ, Luo BY, Zhao YJ, Xu MY, Chen X, Jiang XF, Zhu CM, Jin XL, Chen HZ, Tan YY, Ning G, Chen JL. Two unusual cases of intractable hyperthyroidism responsive to octreotide: Munchausen syndrome or not? Clin Chim Acta 2011; 412:1155-60. [PMID: 21376025 DOI: 10.1016/j.cca.2011.02.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 02/22/2011] [Accepted: 02/23/2011] [Indexed: 11/30/2022]
Abstract
BACKGROUND The effective treatment for patients with resistant hyperthyroidism is difficult. METHODS In this case report with 4-year follow-up data, we present 2 unusual cases of hyperthyroidism that were unresponsive to almost all antithyroid treatments including total thyroidectomy, but both were controlled with octreotide. RESULTS Cases 1 and 2 were both middle-aged women. They presented thyrotoxicosis with a low serum concentration of TSH and thyroidal radioactive iodine uptake (RAIU). The underlying causes, such as thyroiditis, metastatic thyroid cancer and struma ovarii were explored. Iodine-induced hyperthyroidism, particularly factitious hyperthyroidism was highly suspected, but there was no direct evidence to establish these diagnoses. In spite of good compliance, their thyrotoxicosis could not be controlled with large doses of PTU or MMI. β-blocker, methylprednisolone, radio-iodine therapy and even thyroidectomy were all attempted and failed. Short-acting octreotide was first administered to case 1 and then to case 2. Thyroid function improved greatly within 3 days in both cases. The doses of octreotide were tapered down to twice a week with consistent efficacy. During the follow-up periods, case 1 required octreotide 0.1mg twice per week and case 2 is on thyroid replacement therapy due to hypothyroidism. The recurrences of hyperthyroidism in both cases were again rapidly controlled with the increased dose of octreotide in case 1 and re-started the usage of octreotide in case 2. CONCLUSIONS The etiology of thyrotoxicosis in these 2 cases is not clear. In the absence of struma ovarii or wide-spread follicular thyroid cancer, factitious hyperthyroidism due to Munchausen syndrome should be considered first. The efficacy of the off-label use of octreotide in hyperthyroidism was highly effective (only) in these 2 cases.
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Affiliation(s)
- Jian-Min Liu
- Department of Endocrine and Metabolic Diseases, Shanghai Rui-jin Hospital, Shanghai Jiao-tong University School of Medicine, China.
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Cakir M, Dworakowska D, Grossman A. Somatostatin receptor biology in neuroendocrine and pituitary tumours: part 2--clinical implications. J Cell Mol Med 2010; 14:2585-91. [PMID: 20629988 PMCID: PMC4373478 DOI: 10.1111/j.1582-4934.2010.01125_1.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Accepted: 04/29/2010] [Indexed: 01/03/2023] Open
Abstract
Introduction
SSTR subtype tissue distribution and its relevance to tumour imaging and treatment
Conclusions
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Affiliation(s)
- Mehtap Cakir
- Selcuk University, Meram School of Medicine, Division of Endocrinology and Metabolism, Konya, Turkey.
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Arnaldi G, Boscaro M. Pasireotide for the treatment of Cushing's disease. Expert Opin Investig Drugs 2010; 19:889-98. [DOI: 10.1517/13543784.2010.495943] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Córdoba-Chacón J, Gahete MD, Duran-Prado M, Pozo-Salas AI, Malagón MM, Gracia-Navarro F, Kineman RD, Luque RM, Castaño JP. Identification and characterization of new functional truncated variants of somatostatin receptor subtype 5 in rodents. Cell Mol Life Sci 2010; 67:1147-63. [PMID: 20063038 PMCID: PMC11115927 DOI: 10.1007/s00018-009-0240-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 12/08/2009] [Accepted: 12/18/2009] [Indexed: 12/11/2022]
Abstract
Somatostatin and cortistatin exert multiple biological actions through five receptors (sst1-5); however, not all their effects can be explained by activation of sst1-5. Indeed, we recently identified novel truncated but functional human sst5-variants, present in normal and tumoral tissues. In this study, we identified and characterized three novel truncated sst5 variants in mice and one in rats displaying different numbers of transmembrane-domains [TMD; sst5TMD4, sst5TMD2, sst5TMD1 (mouse-variants) and sst5TMD1 (rat-variant)]. These sst5 variants: (1) are functional to mediate ligand-selective-induced variations in [Ca(2+)]i and cAMP despite being truncated; (2) display preferential intracellular distribution; (3) mostly share full-length sst5 tissue distribution, but exhibit unique differences; (4) are differentially regulated by changes in hormonal/metabolic environment in a tissue- (e.g., central vs. systemic) and ligand-dependent manner. Altogether, our results demonstrate the existence of new truncated sst5-variants with unique ligand-selective signaling properties, which could contribute to further understanding the complex, distinct pathophysiological roles of somatostatin and cortistatin.
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Affiliation(s)
- Jose Córdoba-Chacón
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Manuel D. Gahete
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Mario Duran-Prado
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Ana I. Pozo-Salas
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - María M. Malagón
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - F. Gracia-Navarro
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Rhonda D. Kineman
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL USA
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL USA
| | - Raul M. Luque
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Justo P. Castaño
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
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Ben-Shlomo A, Melmed S. Pituitary somatostatin receptor signaling. Trends Endocrinol Metab 2010; 21:123-33. [PMID: 20149677 PMCID: PMC2834886 DOI: 10.1016/j.tem.2009.12.003] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Revised: 12/09/2009] [Accepted: 12/10/2009] [Indexed: 12/27/2022]
Abstract
Somatotropin-release inhibitory factor (SRIF) is a major regulator of pituitary function, mostly inhibiting hormone secretion and to a lesser extent pituitary cell growth. Five SRIF receptor subtypes (SSTR1-5) are ubiquitously expressed G-protein coupled receptors. In the pituitary, SSTR1, 2, 3 and 5 are expressed, with SSTR2 and SSTR5 predominating. As new SRIF analogs have recently been introduced for treatment of pituitary disease, we evaluate the current knowledge of cell-specific pituitary SRIF receptor signaling and highlight areas of future research for comprehensive understanding of these mechanisms. Elucidating pituitary SRIF receptor signaling enables understanding of pituitary hormone secretion and cell growth, and also encourages future therapeutic development for pituitary disorders.
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Affiliation(s)
- Anat Ben-Shlomo
- Pituitary Center, Department of Medicine, Cedars Sinai Medical Center, Los Angeles, California 90048, USA
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32
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Martino MCD, Hofland LJ, Lamberts SW. Somatostatin and Somatostatin Receptors: from Basic Concepts to Clinical Applications. PROGRESS IN BRAIN RESEARCH 2010; 182:255-80. [DOI: 10.1016/s0079-6123(10)82011-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Stewart PM, Petersenn S. Rationale for treatment and therapeutic options in Cushing's disease. Best Pract Res Clin Endocrinol Metab 2009; 23 Suppl 1:S15-22. [PMID: 20129190 DOI: 10.1016/s1521-690x(09)70004-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cushing's disease results from prolonged overexposure of tissues to endogenous glucocorticoids, secondary to adrenocorticotrophin excess from the pituitary. Common clinical signs and symptoms include weight gain, hypertension, and osteoporosis. Effective treatment of Cushing's disease can normalize biochemical levels, reverse comorbidities, and improve overall survival and quality of life. Treatment options include pituitary or adrenal surgery, radiotherapy, and various medical therapies, but each has important limitations. Medical therapies that effectively target the pituitary tumour are urgently needed.
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Affiliation(s)
- Paul M Stewart
- Centre for Endocrinology, Diabetes and Metabolism, Clinical & Experimental Medicine, College of Medical & Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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Immunohistochemical detection of somatostatin receptor subtype 5 (SSTR-5) in cushing adenoma. J Neurooncol 2009; 98:151-2. [DOI: 10.1007/s11060-009-0048-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 10/26/2009] [Indexed: 11/25/2022]
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35
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Bibliography. Current world literature. Curr Opin Endocrinol Diabetes Obes 2009; 16:328-37. [PMID: 19564733 DOI: 10.1097/med.0b013e32832eb365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
While surgery remains the first-line treatment of most aggressive pituitary adenomas, medical therapy is important as second-line or adjunctive therapy in a large proportion of patients. Dopamine agonists (DAs) are the best treatment for prolactinomas, but when DAs are not tolerated, new somatostatin receptor subtype 5 (SSTR(5)) inhibitors may offer an alternative in the future. Unfortunately, these are unlikely to be effective in DA-resistant prolactinomas. In acromegaly, the existing somatostatin analogs, octreotide and lanreotide, will remain the medical treatment of choice for the foreseeable future. There is an urgent need for medical therapies in Cushing's disease, and the SSTR(5) analogs could offer an effective treatment in a proportion of patients within the next few years. Finally, the medical management options for non-functioning pituitary adenomas are also very limited, and a new chimeric agent with activity towards dopamine receptors, SSTR(5) and SSTR(2) may help reduce adenoma recurrence in the future.
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Affiliation(s)
- Steven W J Lamberts
- Department of Internal Medicine, Division of Endocrinology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands.
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37
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Gahete MD, Durán-Prado M, Luque RM, Martínez-Fuentes AJ, Vázquez-Martínez R, Malagón MM, Castaño JP. Are somatostatin and cortistatin two siblings in regulating endocrine secretions? In vitro work ahead. Mol Cell Endocrinol 2008; 286:128-34. [PMID: 18215456 DOI: 10.1016/j.mce.2007.11.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2007] [Revised: 11/17/2007] [Accepted: 11/17/2007] [Indexed: 10/22/2022]
Abstract
Somatostatin (SRIF) and cortistatin (CST) are two cyclic peptides sharing remarkable structural, pharmacological and functional similarities. Both peptides bind all somatostatin receptors subtypes (sst1-5) with comparable affinities, which may explain the considerable similitude between their actions, particularly on endocrine targets. However, the expression patterns of both peptides do not overlap in human tissues, and they are regulated by different stimuli, suggesting that SRIF and CST can exert unique roles. In fact, CST can bind other receptors, different to ssts (e.g. ghrelin receptor, GHS-R and the MrgX2 receptor), which may be involved in those differential actions. In this review, we have summarized the limited knowledge gathered so far regarding the in vitro actions exerted by CST in different endocrine systems under normal and pathophysiological conditions, and have compared them with the well established functions known for SRIF on these systems. Available data suggests that CST substantially reproduces, but not fully mimics the "in vitro" effects of SRIF on pituitary secretions of human and animal models. Conversely, the functions of CST in the majority of peripheral endocrine (and non-endocrine) tissues are still unknown. Notwithstanding this, the differential tissue expression pattern of SRIF, CST and their receptors suggests that CST may act as a mere natural SRIF analogue in a number of tissues but in some endocrine tissues it may play a predominant, unique regulatory role with potential pathophysiological relevance. The challenge is now to find the genuine differences between these seemingly identical endocrine siblings.
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Affiliation(s)
- Manuel D Gahete
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
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