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Kumar U. Somatostatin and Somatostatin Receptors in Tumour Biology. Int J Mol Sci 2023; 25:436. [PMID: 38203605 PMCID: PMC10779198 DOI: 10.3390/ijms25010436] [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: 11/03/2023] [Revised: 12/24/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
Somatostatin (SST), a growth hormone inhibitory peptide, is expressed in endocrine and non-endocrine tissues, immune cells and the central nervous system (CNS). Post-release from secretory or immune cells, the first most appreciated role that SST exhibits is the antiproliferative effect in target tissue that served as a potential therapeutic intervention in various tumours of different origins. The SST-mediated in vivo and/or in vitro antiproliferative effect in the tumour is considered direct via activation of five different somatostatin receptor subtypes (SSTR1-5), which are well expressed in most tumours and often more than one receptor in a single cell. Second, the indirect effect is associated with the regulation of growth factors. SSTR subtypes are crucial in tumour diagnosis and prognosis. In this review, with the recent development of new SST analogues and receptor-specific agonists with emerging functional consequences of signaling pathways are promising therapeutic avenues in tumours of different origins that are discussed.
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Affiliation(s)
- Ujendra Kumar
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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2
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Higashida H, Furuhara K, Yamauchi AM, Deguchi K, Harashima A, Munesue S, Lopatina O, Gerasimenko M, Salmina AB, Zhang JS, Kodama H, Kuroda H, Tsuji C, Suto S, Yamamoto H, Yamamoto Y. Intestinal transepithelial permeability of oxytocin into the blood is dependent on the receptor for advanced glycation end products in mice. Sci Rep 2017; 7:7883. [PMID: 28801574 PMCID: PMC5554167 DOI: 10.1038/s41598-017-07949-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 07/06/2017] [Indexed: 12/24/2022] Open
Abstract
Plasma oxytocin (OT) originates from secretion from the pituitary gland into the circulation and from absorption of OT in mother's milk into the blood via intestinal permeability. However, the molecular mechanism underlying the absorption of OT remains unclear. Here, we report that plasma OT concentrations increased within 10 min after oral delivery in postnatal day 1-7 mice. However, in Receptors for Advanced Glycation End Products (RAGE) knockout mice after postnatal day 3, an identical OT increase was not observed. In adult mice, plasma OT was also increased in a RAGE-dependent manner after oral delivery or direct administration into the intestinal tract. Mass spectrometry evaluated that OT was absorbed intact. RAGE was abundant in the intestinal epithelial cells in both suckling pups and adults. These data highlight that OT is transmitted via a receptor-mediated process with RAGE and suggest that oral OT supplementation may be advantageous in OT drug development.
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Affiliation(s)
- Haruhiro Higashida
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan.
| | - Kazumi Furuhara
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Agnes-Mikiko Yamauchi
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Kisaburo Deguchi
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Ai Harashima
- Departments of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, 920-8640, Japan
| | - Seiichi Munesue
- Departments of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, 920-8640, Japan
| | - Olga Lopatina
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan.,Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, 660022, Russia
| | - Maria Gerasimenko
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Alla B Salmina
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan.,Department of Biochemistry, Medical, Pharmaceutical and Toxicological Chemistry, Krasnoyarsk State Medical University named after Prof. V.F. Voino-Yasenetsky, Krasnoyarsk, 660022, Russia
| | - Jia-Sheng Zhang
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan.,Department of Pathology, University of California, San Francisco, San Francisco, CA, 94143, USA
| | - Hikari Kodama
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Hironori Kuroda
- Departments of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, 920-8640, Japan
| | - Chiharu Tsuji
- Department of Basic Research on Social Recognition and Memory, Research Centre for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Satoshi Suto
- Faculty of Pharmaceutical Sciences and Center for Research and Education on Drug Discovery, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo, 060-0812, Japan
| | - Hiroshi Yamamoto
- Departments of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, 920-8640, Japan
| | - Yasuhiko Yamamoto
- Departments of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, 920-8640, Japan
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Villa-Osaba A, Gahete MD, Córdoba-Chacón J, de Lecea L, Pozo-Salas AI, Delgado-Lista FJ, Álvarez-Benito M, López-Miranda J, Luque RM, Castaño JP. Obesity alters gene expression for GH/IGF-I axis in mouse mammary fat pads: differential role of cortistatin and somatostatin. PLoS One 2015; 10:e0120955. [PMID: 25806796 PMCID: PMC4373840 DOI: 10.1371/journal.pone.0120955] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 02/10/2015] [Indexed: 12/03/2022] Open
Abstract
Locally produced growth hormone (GH) and IGF-I are key factors in the regulation of mammary gland (MG) development and may be important in breast cancer development/progression. Somatostatin (SST) and cortistatin (CORT) regulate GH/IGF-I axis at various levels, but their role in regulating GH/IGF-I in MGs remains unknown. Since obesity alters the expression of these systems in different tissues and is associated to MG (patho) physiology, we sought to investigate the role of SST/CORT in regulating GH/IGF-I system in the MGs of lean and obese mice. Therefore, we analyzed GH/IGF-I as well as SST/CORT and ghrelin systems expression in the mammary fat pads (MFPs) of SST- or CORT-knockout (KO) mice and their respective littermate-controls fed a low-fat (LF) or a high-fat (HF) diet for 16 wks. Our results demonstrate that the majority of the components of GH/IGF-I, SST/CORT and ghrelin systems are locally expressed in mouse MFP. Expression of elements of the GH/IGF-I axis was significantly increased in MFPs of HF-fed control mice while lack of endogenous SST partially suppressed, and lack of CORT completely blunted, the up-regulation observed in obese WT-controls. Since SST/CORT are known to exert an inhibitory role on the GH/IGFI axis, the increase in SST/CORT-receptor sst2 expression in MFPs of HF-fed CORT- and SST-KOs together with an elevation on circulating SST in CORT-KOs could explain the differences observed. These results offer new information on the factors (GH/IGF-I axis) involved in the endocrine/metabolic dysregulation of MFPs in obesity, and suggest that CORT is not a mere SST sibling in regulating MG physiology.
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Affiliation(s)
- Alicia Villa-Osaba
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - Manuel D. Gahete
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - José Córdoba-Chacón
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
- Department of Medicine, University of Illinois at Chicago and Jesse Brown Veteran Affairs Medical Center, Research and Development Division, Chicago, Illinois, United States of America
| | - Luis de Lecea
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Ana I. Pozo-Salas
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
| | - Francisco Javier Delgado-Lista
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- Lipids and Atherosclerosis Unit, Department of Medicine, Reina Sofía University Hospital, Córdoba, Spain
| | - Marina Álvarez-Benito
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- Mammary Gland Unit, Reina Sofía University Hospital, Córdoba, Spain
| | - José López-Miranda
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
- Lipids and Atherosclerosis Unit, Department of Medicine, Reina Sofía University Hospital, Córdoba, Spain
| | - Raúl M. Luque
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
| | - Justo P. Castaño
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Reina Sofía University Hospital, Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
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4
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Grönberg M, Fjällskog ML, Jirström K, Janson ET. Expression of ghrelin is correlated to a favorable outcome in invasive breast cancer. Acta Oncol 2012; 51:386-93. [PMID: 22067021 DOI: 10.3109/0284186x.2011.631576] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Expression of the peptide hormones ghrelin and obestatin has previously been demonstrated in human mammary glands. However, the clinical implications of the expression of these peptides in breast cancer are unclear. The aim of this study was to investigate the potential clinical value of ghrelin and obestatin as breast cancer biomarkers. METHODS A tissue microarray containing breast cancer specimens from 144 patients was immunostained with antibodies directed towards ghrelin and obestatin. Using varying cut-offs, the expression of the two peptides was evaluated and correlated to previously known prognostic factors in breast cancer and to the outcome. Cox regression analysis was used to assess whether these markers may predict survival of breast cancer patients. RESULTS Moderate to strong immunoreactivity for ghrelin and obestatin was observed in 71.5% and 77.1% of the cases, respectively. Ghrelin and obestatin expression was significantly but weakly correlated to low histological grade, estrogen receptor positivity, small tumor size and low proliferation. Only ghrelin expression was significantly correlated to better recurrence-free and breast cancer-specific survival (HR = 0.3-0.4, p = 0.02-0.05) in both uni- and multivariate analyses. The optimal cut-off was any ghrelin expression versus none. Reproducibility between the two readers was very good for both stainings with kappa values of 0.94-1.00. CONCLUSIONS Patients with tumors expressing ghrelin had 2.5-3 times lower risk for recurrence or breast cancer death than those lacking ghrelin expression. Ghrelin expression is easily assessable with high reproducibility using immunohistochemistry. Further investigations are needed to establish the clinical significance of ghrelin as a biomarker in breast cancer.
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MESH Headings
- Adenocarcinoma/metabolism
- Adenocarcinoma/mortality
- Adenocarcinoma/pathology
- Adult
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/metabolism
- Breast Neoplasms/metabolism
- Breast Neoplasms/mortality
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/mortality
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Lobular/metabolism
- Carcinoma, Lobular/mortality
- Carcinoma, Lobular/pathology
- Carcinoma, Medullary/metabolism
- Carcinoma, Medullary/mortality
- Carcinoma, Medullary/pathology
- Case-Control Studies
- Cohort Studies
- Female
- Gastric Mucosa/metabolism
- Ghrelin/metabolism
- Humans
- Immunoenzyme Techniques
- Middle Aged
- Neoplasm Invasiveness
- Neoplasm Recurrence, Local/metabolism
- Neoplasm Recurrence, Local/mortality
- Neoplasm Recurrence, Local/pathology
- Neoplasm Staging
- Prognosis
- Survival Rate
- Tissue Array Analysis
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Affiliation(s)
- Malin Grönberg
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden.
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5
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Abstract
The milk of many mammalian species contains hormones and growth factors in addition to nutrients and immuocompetent substances. These factors can be absorbed into the circulation of suckling neonates to exert important effects on metabolism and promote tissue and organ growth. Frequently, there is uncertainty as to whether such substances are gene products of the mammary glands themselves or are produced elsewhere and concentrated from the systemic circulation. The 6 kD polypeptide, relaxin, appears in milk of several mammalian species, including that of the rat, but proof of its source of secretion (corpus luteum vs. mammary gland) is so far lacking. The specific monoclonal anti-rat relaxin antibody MCA1 has previously been utilized successfully to investigate many of relaxin’s actions in the rat, including those affecting the development of the mammary apparatus. In this report, MCA1 was utilized to aid in the identification of the source of relaxin in rat milk. Treatment of lactating rats with MCA1 completely neutralized the luteal relaxin circulating in serum but did not decrease the concentration of immunoactive relaxin secreted in milk. Moreover, the antibody did not appear to reach the mammary epithelium. The evidence thus supports the view that in the rat, the relaxin secreted in milk is primarily a product of the mammary glands and not concentrated from the systemic circulation.
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6
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Odaka C, Izumiyama S. Expression of stromelysin-3 (matrix metalloproteinase-11) in macrophages of murine thymus following thymocyte apoptosis. Cell Immunol 2005; 235:21-8. [PMID: 16165118 DOI: 10.1016/j.cellimm.2005.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Revised: 06/07/2005] [Accepted: 06/20/2005] [Indexed: 11/21/2022]
Abstract
High expression of stromelysin-3 (ST-3), also known as matrix metalloproteinase-11, has been implicated in tumor progression and intense tissue remodeling. Nonetheless, details of the cell type(s) expressing ST-3 are less well defined. Here, we report that ST-3 expression was elevated in mouse thymus following thymocyte apoptosis after administration of anti-CD3 Ab. TUNEL analysis revealed that many thymocytes in the cortical region were induced to apoptotic cell death 14 h after the injection. After an additional 2-6 h, ST-3 expression in the thymus was more apparent. Co-staining analysis by anti-ST-3 and F4/80 Abs showed that most F4/80-positive macrophages were also positive for ST-3. Murine peritoneal macrophages were found to constitutively express ST-3, and exposure to apoptotic cells hardly affected ST-3 expression in the macrophages. Taken together, our results indicate that ST-3 is not involved in the execution process of thymocyte apoptosis, and the increased levels of ST-3 in the thymus may be due to the presence of macrophages responsible for clearance of apoptotic cells.
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Affiliation(s)
- Chikako Odaka
- Department of Safety Research on Blood and Biological Products, National Institute of Infectious Diseases, Tokyo, Japan.
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7
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Matsuda M, Imaoka T, Vomachka AJ, Gudelsky GA, Hou Z, Mistry M, Bailey JP, Nieport KM, Walther DJ, Bader M, Horseman ND. Serotonin Regulates Mammary Gland Development via an Autocrine-Paracrine Loop. Dev Cell 2004; 6:193-203. [PMID: 14960274 DOI: 10.1016/s1534-5807(04)00022-x] [Citation(s) in RCA: 181] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2003] [Revised: 12/12/2003] [Accepted: 12/19/2003] [Indexed: 11/18/2022]
Abstract
Mammary gland development is controlled by a dynamic interplay between endocrine hormones and locally produced factors. Biogenic monoamines (serotonin, dopamine, norepinephrine, and others) are an important class of bioregulatory molecules that have not been shown to participate in mammary development. Here we show that mammary glands stimulated by prolactin (PRL) express genes essential for serotonin biosynthesis (tryptophan hydroxylase [TPH] and aromatic amine decarboxylase). TPH mRNA was elevated during pregnancy and lactation, and serotonin was detected in the mammary epithelium and in milk. TPH was induced by PRL in mammosphere cultures and by milk stasis in nursing dams, suggesting that the gene is controlled by milk filling in the alveoli. Serotonin suppressed beta-casein gene expression and caused shrinkage of mammary alveoli. Conversely, TPH1 gene disruption or antiserotonergic drugs resulted in enhanced secretory features and alveolar dilation. Thus, autocrine-paracrine serotonin signaling is an important regulator of mammary homeostasis and early involution.
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MESH Headings
- Animals
- Animals, Newborn
- Aromatic-L-Amino-Acid Decarboxylases/genetics
- Aromatic-L-Amino-Acid Decarboxylases/metabolism
- Autocrine Communication/drug effects
- Autocrine Communication/physiology
- Caseins/genetics
- Caseins/metabolism
- Cells, Cultured
- Cloning, Molecular
- Dialysis
- Dose-Response Relationship, Drug
- Drug Interactions
- Epithelial Cells/drug effects
- Epithelial Cells/metabolism
- Female
- Fenclonine/pharmacology
- Gene Expression Regulation, Developmental
- Histology
- Humans
- Hydroxyindoleacetic Acid/metabolism
- Immunohistochemistry
- In Situ Hybridization
- Lactalbumin/genetics
- Lactalbumin/metabolism
- Mammary Glands, Human/cytology
- Mammary Glands, Human/drug effects
- Mammary Glands, Human/growth & development
- Methysergide/pharmacology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Milk/metabolism
- Milk Proteins/genetics
- Milk Proteins/metabolism
- Mucins/genetics
- Mucins/metabolism
- Organ Culture Techniques
- Paracrine Communication/drug effects
- Paracrine Communication/physiology
- Pregnancy
- Prolactin/deficiency
- Prolactin/genetics
- Prolactin/metabolism
- RNA, Messenger/biosynthesis
- Reverse Transcriptase Polymerase Chain Reaction
- Serotonin/physiology
- Serotonin Antagonists/pharmacology
- Time Factors
- Tryptophan Hydroxylase/genetics
- Tryptophan Hydroxylase/metabolism
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Affiliation(s)
- Manabu Matsuda
- Department of Molecular and Cellular Physiology, University of Cincinnati, Cincinnati, OH 45221, USA
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Cassoni P, Papotti M, Ghè C, Catapano F, Sapino A, Graziani A, Deghenghi R, Reissmann T, Ghigo E, Muccioli G. Identification, characterization, and biological activity of specific receptors for natural (ghrelin) and synthetic growth hormone secretagogues and analogs in human breast carcinomas and cell lines. J Clin Endocrinol Metab 2001; 86:1738-45. [PMID: 11297611 DOI: 10.1210/jcem.86.4.7402] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The family of GH secretagogues (GHS) includes synthetic peptidyl (hexarelin) and nonpeptidyl (MK-0677) molecules possessing specific receptors in the pituitary and central nervous system as well as in peripheral tissues, including the heart and some endocrine organs. A gastric-derived peptide, named ghrelin, has recently been proposed as the natural ligand of the GHS receptors (GHS-Rs). The presence of specific GHS-Rs has now been investigated in nontumoral and neoplastic human breast tissue using a radioiodinated peptidyl GHS ([(125)I]-Tyr-Ala-hexarelin) as ligand. Specific binding sites for GHS were detected in membranes from several types of breast carcinomas, whereas a negligible binding was found in fibroadenomas and mammary parenchyma. The highest binding activity was found in well-differentiated (G1) invasive breast carcinomas and was progressively reduced in moderately (G2) to poorly (G3) differentiated tumors. [(125)I]-Tyr-Ala-hexarelin bound to tumor membranes was displaced by different unlabeled GHS such as hexarelin, Tyr-Ala-hexarelin, human ghrelin, and MK-0677 as well as by desoctanoyl-ghrelin and hexarelin derivative EP-80317, which are devoid of GH-releasing properties in vivo. In contrast, no competition was seen between radiolabeled Tyr-Ala-hexarelin and some peptides (CRF and insulin-like growth factor I) structurally and functionally unrelated to hexarelin or when GHRH and SRIF were tested in the displacement studies. The presence of specific GHS binding sites was also demonstrated in three different human breast carcinoma cell lines (MCF7, T47D, and MDA-MB231), in which, surprisingly, no messenger RNA for GHS-R1a was demonstrated by RT-PCR. In these cell lines, ghrelin (as well as hexarelin, MK-0677, EP-80317, and even desoctanoyl ghrelin) caused a significant inhibition of cell proliferation at concentrations close to their binding affinity. In conclusion, this study provides the first demonstration of specific GHS binding sites, other than GHS-R1, in breast cancer. These receptors probably mediate growth inhibitory effects on breast carcinoma cells in vitro.
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Affiliation(s)
- P Cassoni
- Department of Biomedical Sciences and Oncology, University of Turin, 10126 Turin, Italy.
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