1
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Vijayashankar U, Ramashetty R, Rajeshekara M, Vishwanath N, Yadav AK, Prashant A, Lokeshwaraiah R. Leptin and ghrelin dynamics: unraveling their influence on food intake, energy balance, and the pathophysiology of type 2 diabetes mellitus. J Diabetes Metab Disord 2024; 23:427-440. [PMID: 38932792 PMCID: PMC11196531 DOI: 10.1007/s40200-024-01418-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 03/12/2024] [Indexed: 06/28/2024]
Abstract
Purpose Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by insulin resistance and impaired glucose homeostasis. In recent years, there has been growing interest in the role of hunger and satiety hormones such as ghrelin and leptin in the development and progression of T2DM. In this context, the present literature review aims to provide a comprehensive overview of the current understanding of how ghrelin and leptin influences food intake and maintain energy balance and its implications in the pathophysiology of T2DM. Methods A thorough literature search was performed using PubMed and Google Scholar to choose the studies that associated leptin and ghrelin with T2DM. Original articles and reviews were included, letters to editors and case reports were excluded. Results This narrative review article provides a comprehensive summary on mechanism of action of leptin and ghrelin, its association with obesity and T2DM, how they regulate energy and glucose homeostasis and potential therapeutic implications of leptin and ghrelin in managing T2DM. Conclusion Ghrelin, known for its appetite-stimulating effects, and leptin, a hormone involved in the regulation of energy balance, have been implicated in insulin resistance and glucose metabolism. Understanding the complexities of ghrelin and leptin interactions in the context of T2DM may offer insights into novel therapeutic strategies for this prevalent metabolic disorder. Further research is warranted to elucidate the molecular mechanisms underlying these hormone actions and to explore their clinical implications for T2DM prevention and management.
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Affiliation(s)
- Uma Vijayashankar
- Department of Physiology, JSS Medical College, JSS Academy of Higher Education & Research, Mysuru, 570015 India
| | - Rajalakshmi Ramashetty
- Department of Physiology, JSS Medical College, JSS Academy of Higher Education & Research, Mysuru, 570015 India
| | - Mahesh Rajeshekara
- Department of Surgical Gastroenterology, Bangalore Medical College and Research Institute, Bangalore, 560002 India
| | - Nagashree Vishwanath
- Department of Physiology, JSS Medical College, JSS Academy of Higher Education & Research, Mysuru, 570015 India
| | - Anshu Kumar Yadav
- Department of Biochemistry, JSS Medical College, JSS Academy of Higher Education & Research, Mysuru-15, Mysuru, 570015 India
| | - Akila Prashant
- Department of Biochemistry, JSS Medical College, JSS Academy of Higher Education & Research, Mysuru-15, Mysuru, 570015 India
| | - Rajeshwari Lokeshwaraiah
- Department of Physiology, JSS Medical College, JSS Academy of Higher Education & Research, Mysuru, 570015 India
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2
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Chen Y, Han X, Wang L, Wen Q, Li L, Sun L, Chen Q. Multiple roles of ghrelin in breast cancer. Int J Biol Markers 2022; 37:241-248. [PMID: 35763463 DOI: 10.1177/03936155221110247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Breast cancer is one of the most threatening malignant tumors in women worldwide; hence, investigators are continually performing novel research in this field. However, an accurate prediction of its prognosis and postoperative recovery remains difficult. The severity of breast cancer is patient-specific and affected by several health factors; thus, unknown mechanisms may affect its progression. This article analyzes existing literature on breast cancer, ranging from the discovery of ghrelin to its present use, and aims to provide a reference for future research into breast cancer mechanisms and treatment-plan improvement. Various parts of ghrelin have been associated with breast cancer by direct or indirect evidence. The ghrelin system may encompass the direction of expanding breast cancer treatment methods and prognostic indicators. Therefore, we compiled almost all studies on the relationship between the ghrelin system and breast cancer, including unacylated ghrelin, its GHRL gene, ghrelin O-acyltransferase, the receptor growth hormone secretagogue receptor, and several splice variants of ghrelin to lay the foundation for future research.
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Affiliation(s)
- Yiding Chen
- 176759Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Xuke Han
- 176759Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Lan Wang
- 176759Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Qing Wen
- 176759Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Liufu Li
- Pengshan District People's Hospital of Meishan City, Meishan, China
| | - Lisha Sun
- 176759Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Qiu Chen
- 176759Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Chengdu University of Traditional Chinese Medicine, Chengdu, China
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3
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Deschaine SL, Leggio L. From "Hunger Hormone" to "It's Complicated": Ghrelin Beyond Feeding Control. Physiology (Bethesda) 2022; 37:5-15. [PMID: 34964687 PMCID: PMC8742734 DOI: 10.1152/physiol.00024.2021] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Discovered as a peptide involved in releasing growth hormone, ghrelin was initially characterized as the "hunger hormone." However, emerging research indicates that ghrelin appears to play an important part in relaying information regarding nutrient availability and value and adjusting physiological and motivational processes accordingly. These functions make ghrelin an interesting therapeutic candidate for metabolic and neuropsychiatric diseases involving disrupted nutrition that can further potentiate the rewarding effect of maladaptive behaviors.
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Affiliation(s)
- Sara L. Deschaine
- 1Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore and Bethesda, Maryland
| | - Lorenzo Leggio
- 1Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Baltimore and Bethesda, Maryland,2Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland,3Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, School of Public Health, Brown University, Providence, Rhode Island,4Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland,5Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia
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4
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Jiménez-Vacas JM, Montero-Hidalgo AJ, Gómez-Gómez E, Fuentes-Fayos AC, Ruiz-Pino F, Guler I, Camargo A, Anglada FJ, Carrasco-Valiente J, Tena-Sempere M, Sarmento-Cabral A, Castaño JP, Gahete MD, Luque RM. In1-Ghrelin Splicing Variant as a Key Element in the Pathophysiological Association Between Obesity and Prostate Cancer. J Clin Endocrinol Metab 2021; 106:e4956-e4968. [PMID: 34255835 DOI: 10.1210/clinem/dgab516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
CONTEXT Recent studies emphasize the importance of considering the metabolic status to develop personalized medicine approaches. This is especially relevant in prostate cancer (PCa), wherein the diagnostic capability of prostate-specific antigen (PSA) dramatically drops when considering patients with PSA levels ranging from 3 to 10 ng/mL, the so-called grey zone. Hence, additional noninvasive diagnostic and/or prognostic PCa biomarkers are urgently needed, especially in the metabolic-status context. OBJECTIVE To assess the potential relation of urine In1-ghrelin (a ghrelin-splicing variant) levels with metabolic-related/pathological conditions (eg, obesity, diabetes, body mass index, insulin and glucose levels) and to define its potential clinical value in PCa (diagnostic/prognostic capacity) and relationship with PCa risk in patients with PSA in the grey zone. METHODS Urine In1-ghrelin levels were measured by radioimmunoassay in a clinically, metabolically, pathologically well-characterized cohort of patients without (n = 397) and with (n = 213) PCa with PSA in the grey zone. RESULTS Key obesity-related factors associated with PCa risk (BMI, diabetes, glucose and insulin levels) were strongly correlated to In1-ghrelin levels. Importantly, In1-ghrelin levels were higher in PCa patients compared to control patients with suspect of PCa but negative biopsy). Moreover, high In1-ghrelin levels were associated with increased PCa risk and linked to PCa aggressiveness (eg, tumor stage, lymphovascular invasion). In1-ghrelin levels added significant diagnostic value to a clinical model consisting of age, suspicious digital rectal exam, previous biopsy, and PSA levels. Furthermore, a multivariate model consisting of clinical and metabolic variables, including In1-ghrelin levels, showed high specificity and sensitivity to diagnose PCa (area under the receiver operating characteristic curve = 0.740). CONCLUSIONS Urine In1-ghrelin levels are associated with obesity-related factors and PCa risk and aggressiveness and could represent a novel and valuable noninvasive PCa biomarker, as well as a potential link in the pathophysiological relationship between obesity and PCa.
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Affiliation(s)
- Juan M Jiménez-Vacas
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Antonio J Montero-Hidalgo
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Enrique Gómez-Gómez
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- Urology Service, HURS/IMIBIC, Cordoba, Spain
| | - Antonio C Fuentes-Fayos
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Francisco Ruiz-Pino
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Ipek Guler
- Leuven Biostatistics and Statistical Bioinformatics Centre (L-BioStat), Katholiek Universiteit (KU) Leuven, University of Leuven, Leuven, Belgium
| | - Antonio Camargo
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
- Lipids and Atherosclerosis Unit, Internal Medicine Unit, Reina Sofia University Hospital, Cordoba, Spain
| | - Francisco J Anglada
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- Urology Service, HURS/IMIBIC, Cordoba, Spain
| | - Julia Carrasco-Valiente
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- Urology Service, HURS/IMIBIC, Cordoba, Spain
| | - Manuel Tena-Sempere
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - André Sarmento-Cabral
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Justo P Castaño
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Manuel D Gahete
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
| | - Raúl M Luque
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Cordoba, Spain
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Cordoba, Spain
- Reina Sofia University Hospital (HURS), Cordoba, Spain
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Cordoba, Spain
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5
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Tegshee B, Kondo K, Soejima S, Muguruma K, Tsuboi M, Kajiura K, Kawakami Y, Kawakita N, Toba H, Yoshida M, Takizawa H, Tangoku A. GHSR methylation-dependent expression of a variant ligand and receptor of the ghrelin system induces thymoma tumorigenesis. Oncol Lett 2021; 22:793. [PMID: 34630704 PMCID: PMC8477069 DOI: 10.3892/ol.2021.13054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 08/19/2021] [Indexed: 12/17/2022] Open
Abstract
Our previous study reported that the DNA methylation of growth hormone secretagogue receptor (GHSR) was significantly higher in thymoma or thymic carcinoma (TC) than in normal thymic tissue samples. Thymic epithelial tumors (TETs) with higher GHSR DNA methylation were associated with significantly worse prognosis than those with lower levels of DNA methylation. Diversified components of the ghrelin-GHSR axis may exert opposing effects in cancer progression, depending on the cancer type in question. However, the precise function of the axis remains unclear. In the present study, the mRNA expression of five key components of the ghrelin system [native ligand ghrelin, variant ligand In-1 ghrelin, native receptor GHSR1a, variant receptor GHSR1b and acylation enzyme ghrelin O-acyltransferase (GOAT)] were examined in 58 TET samples by reverse transcription-quantitative PCR, and protein expression of GHSR1a and GHSR1b was assessed in 20 TETs using immunohistochemistry. The results revealed that In-1 ghrelin, GHSR1b (variant forms) and GOAT were more strongly expressed in thymoma compared with thymic-adjacent tissue. By contrast, no significant differences were observed in the expression of ghrelin and GHSR1a (native forms) between thymoma and thymic tissue. The mRNA expression of In-1 ghrelin and GHSR1b (variant forms) was positively associated with GHSR methylation in thymoma tissue samples. However, a relationship was not found between ghrelin, GHSR1a or GOAT expression (native forms) and GHSR methylation in thymoma. Immunohistochemical analysis revealed that mRNA expression of GHSR1a and GHSR1b generally correlated with expression of the corresponding protein, and that the expression of GHSR1b was increased in advanced-stage TETs. These results indicate that the DNA methylation of GHSR is associated with a shift from native expression (ghrelin and GHSR1a) to variant expression (In-1 ghrelin and GHSR1b), which induces the tumorigenesis of thymoma, but not TC.
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Affiliation(s)
- Bilguun Tegshee
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima 770-8509, Japan
| | - Kazuya Kondo
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima 770-8509, Japan
| | - Shiho Soejima
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima 770-8509, Japan
| | - Kyoka Muguruma
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Tokushima 770-8509, Japan
| | - Mitsuhiro Tsuboi
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Koichiro Kajiura
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Yukikiyo Kawakami
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Naoya Kawakita
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Hiroaki Toba
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Mitsuteru Yoshida
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Hiromitsu Takizawa
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
| | - Akira Tangoku
- Department of Thoracic, Endocrine Surgery and Oncology, Graduate School of Biomedical Sciences, Tokushima University, Kuramoto-cho, Tokushima 770-8503, Japan
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6
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Influence of obestatin on the histological development of the small intestine in piglets during the first week of postnatal life. Animal 2020; 14:2129-2137. [PMID: 32398171 DOI: 10.1017/s1751731120000919] [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] [Indexed: 01/04/2023] Open
Abstract
Obestatin is a gastrointestinal peptide having wide-ranging effects on cell proliferation; however, its mechanism of action remains poorly understood. Thus, the aim of the study was to elucidate the effect of exogenous obestatin on the postnatal structural development of the small intestine. Seven-day-old piglets with an average BW of 1.56 ± 0.23 kg were divided into four groups (n = 10) that received intragastrically obestatin (2, 10 or 15 μg/kg BW) or vehicle. After a 6-day experimental period, morphological analysis of gastrointestinal tract and small intestine wall (mitosis and apoptosis indexes, histomorphometry of mucosa and muscularis layers) was performed. The study revealed a seemingly incoherent pattern of the histological structure of the small intestine among the experimental groups, suggesting that the effect of obestatin is both intestinal segment specific and dose dependent. Histomorphometric analysis of the small intestine showed that higher doses of obestatin seem to promote the structural development of the duodenum while simultaneously hindering the maturation of more distal parts of the intestine. Intragastric administration of obestatin increased the crypt mitotic index in all segments of the small intestine with the strongest pro-mitotic activity following the administration of obestatin at a dose of 10 and 15 μg/kg BW. The significant differences in the number of apoptotic cells in the intestinal villi among the groups were observed only in proximal jejunum and ileum. In conclusion, it seems that obestatin shows a broad-spectrum of activity in the gastrointestinal tract of newborn piglets, being able to accelerate its structural development. However, the varied effect depending on the intestinal segment or the concentration of exogenous obestatin causes that further research is needed to clarify the exact mechanism of this phenomenon.
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7
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Grönberg M, Nilsson C, Markholm I, Hedenfalk I, Blomqvist C, Holmberg L, Tiensuu Janson E, Fjällskog ML. Ghrelin expression is associated with a favorable outcome in male breast cancer. Sci Rep 2018; 8:13586. [PMID: 30206250 PMCID: PMC6134078 DOI: 10.1038/s41598-018-31783-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/24/2018] [Indexed: 12/11/2022] Open
Abstract
Ghrelin and obestatin are two gastrointestinal peptides, derived from a common precursor. Expression of both peptides have been found in breast cancer tissue and ghrelin has been associated with breast cancer development. Ghrelin expression is associated with longer survival in women diagnosed with invasive and node negative breast cancer. The clinical implications of the peptide expression in male breast cancer are unclear. The aim of this study was to investigate the role and potential clinical value of ghrelin and obestatin in male breast cancer. A tissue microarray of invasive male breast cancer specimens from 197 patients was immunostained with antibodies versus the two peptides. The expression of the peptides was correlated to previously known prognostic factors in breast cancer and to the outcome. No strong correlations were found between ghrelin or obestatin expression and other known prognostic factors. Only ghrelin expression was statistically significantly correlated to breast cancer-specific survival (HR 0.39, 95% CI 0.18–0.83) in univariate analyses and in multivariate models, adjusted for tumor size and node status (HR 0.38, 95% CI 0.17–0.87). HR for obestatin was 0.38 (95% CI 0.11–1.24). Ghrelin is a potential prognostic factor for breast cancer death in male breast cancer. Patients with tumors expressing ghrelin have a 2.5-fold lower risk for breast cancer death than those lacking ghrelin expression. Drugs targeting ghrelin are currently being investigated in clinical studies treating metabolic or nutritional disorders. Ghrelin should be further evaluated in forthcoming studies as a prognostic marker with the aim to be included in decision algorithms.
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Affiliation(s)
- Malin Grönberg
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden.
| | - Cecilia Nilsson
- Center for Clinical Research, Västmanland County Hospital, Västerås, Sweden
| | - Ida Markholm
- Division of Oncology and Pathology, Department of Clinical Sciences, and CREATE Health Strategic Center for Translational Cancer Research, Lund University, Lund, Sweden
| | - Ingrid Hedenfalk
- Division of Oncology and Pathology, Department of Clinical Sciences, and CREATE Health Strategic Center for Translational Cancer Research, Lund University, Lund, Sweden
| | - Carl Blomqvist
- Department of Oncology, Helsinki University, Helsinki, Finland.,Department of Oncology, Örebro University Hospital, Örebro, Sweden
| | - Lars Holmberg
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.,Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Eva Tiensuu Janson
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden
| | - Marie-Louise Fjällskog
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden
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8
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Rincón-Fernández D, Culler MD, Tsomaia N, Moreno-Bueno G, Luque RM, Gahete MD, Castaño JP. In1-ghrelin splicing variant is associated with reduced disease-free survival of breast cancer patients and increases malignancy of breast cancer cells lines. Carcinogenesis 2018; 39:447-457. [PMID: 29272342 DOI: 10.1093/carcin/bgx146] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 12/14/2017] [Indexed: 12/20/2022] Open
Abstract
Ghrelin gene generates several variants that regulate multiple pathophysiological functions, including tumor-related processes. In1-ghrelin is a splicing variant that was previously shown to be overexpressed in breast cancer (BCa), where it correlated with proliferation markers; however, its possible association with clinical outcome of BCa patients and underlying mechanisms are still unknown. To address this issue, expression levels and clinical associations of In1-ghrelin were analyzed in a cohort of 117 BCa samples. Additionally, a battery of cellular and molecular assays was implemented using two BCa cell lines (MCF-7 and MDA-MB-231), wherein the role of In1-ghrelin on proliferation, migration, dedifferentiation and signaling pathways was explored. The results generated revealed that high expression of In1-ghrelin in BCa samples was associated with lymph node metastasis and reduced disease-free survival. Indeed, In1-ghrelin overexpression stimulated proliferation and migration in MCF-7 and MDA-MB-231 cells. Similar results were found by treating MDA-MB-231 and MCF-7 with In1-ghrelin-derived peptides. Conversely, In1-ghrelin silencing decreased proliferation and migration capacities of MDA-MB-231. Furthermore, In1-ghrelin (but not ghrelin) overexpression increased the capacity to form mammospheres in both cell lines. These effects could be associated with activation of MAPK-ERK, Jag1/Notch, Wnt/β-catenin and/or TGF-β1 pathways. Altogether, our data indicate that In1-ghrelin could play relevant functional roles in the regulation of BCa development and progression and may provide insights to identify novel biomarkers and new therapeutic approaches for this pathology.
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Affiliation(s)
- David Rincón-Fernández
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, Córdoba, Spain.,Hospital Universitario Reina Sofía, Córdoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Córdoba, Spain
| | | | | | - Gema Moreno-Bueno
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM), Instituto de Investigaciones Biomédicas 'Alberto Sols' (CSIC-UAM), IdiPaz, & MD Anderson International Foundation & Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Madrid, Spain
| | - Raúl M Luque
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, Córdoba, Spain.,Hospital Universitario Reina Sofía, Córdoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Córdoba, Spain
| | - Manuel D Gahete
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, Córdoba, Spain.,Hospital Universitario Reina Sofía, Córdoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Córdoba, Spain
| | - Justo P Castaño
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, Universidad de Córdoba, Córdoba, Spain.,Hospital Universitario Reina Sofía, Córdoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición (CIBERObn), Córdoba, Spain
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9
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Leptin and ghrelin: Sewing metabolism onto neurodegeneration. Neuropharmacology 2017; 136:307-316. [PMID: 29248481 DOI: 10.1016/j.neuropharm.2017.12.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 12/11/2017] [Accepted: 12/13/2017] [Indexed: 12/23/2022]
Abstract
Life expectancy has considerably increased over the last decades. The negative consequence of this augmented longevity has been a dramatic increase of age-related chronic neurodegenerative diseases, such as Alzheimer's, Parkinson's and multiple sclerosis. Epidemiology is telling us there exists a strong correlation between the neuronal loss characterizing these disorders and metabolic dysfunction. This review aims at presenting the evidence supporting the existence of a molecular system linking metabolism with neurodegeneration, with a specific focus on the role of two hormones with a key role in the regulatory cross talk between metabolic imbalance and the damage of nervous system: leptin and ghrelin. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'
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10
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Hormaechea-Agulla D, Gahete MD, Jiménez-Vacas JM, Gómez-Gómez E, Ibáñez-Costa A, L-López F, Rivero-Cortés E, Sarmento-Cabral A, Valero-Rosa J, Carrasco-Valiente J, Sánchez-Sánchez R, Ortega-Salas R, Moreno MM, Tsomaia N, Swanson SM, Culler MD, Requena MJ, Castaño JP, Luque RM. The oncogenic role of the In1-ghrelin splicing variant in prostate cancer aggressiveness. Mol Cancer 2017; 16:146. [PMID: 28851363 PMCID: PMC5576296 DOI: 10.1186/s12943-017-0713-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 08/15/2017] [Indexed: 01/06/2023] Open
Abstract
Background The Ghrelin-system is a complex, pleiotropic family composed of several peptides, including native-ghrelin and its In1-ghrelin splicing variant, and receptors (GHSR 1a/b), which are dysregulated in various endocrine-related tumors, where they associate to pathophysiological features, but the presence, functional role, and mechanisms of actions of In1-ghrelin splicing variant in prostate-cancer (PCa), is completely unexplored. Herein, we aimed to determine the presence of key ghrelin-system components (native-ghrelin, In1-ghrelin, GHSR1a/1b) and their potential pathophysiological role in prostate cancer (PCa). Methods In1-ghrelin and native-ghrelin expression was evaluated by qPCR in prostate tissues from patients with high PCa-risk (n = 52; fresh-tumoral biopsies), and healthy-prostates (n = 12; from cystoprostatectomies) and correlated with clinical parameters using Spearman-test. In addition, In1-ghrelin and native-ghrelin was measured in plasma from an additional cohort of PCa-patients with different risk levels (n = 30) and control-healthy patients (n = 20). In vivo functional (proliferation/migration) and mechanistic (gene expression/signaling-pathways) assays were performed in PCa-cell lines in response to In1-ghrelin and native-ghrelin treatment, overexpression and/or silencing. Finally, tumor progression was monitored in nude-mice injected with PCa-cells overexpressing In1-ghrelin, native-ghrelin and empty vector (control). Results In1-ghrelin, but not native-ghrelin, was overexpressed in high-risk PCa-samples compared to normal-prostate (NP), and this expression correlated with that of PSA. Conversely, GHSR1a/1b expression was virtually absent. Remarkably, plasmatic In1-ghrelin, but not native-ghrelin, levels were also higher in PCa-patients compared to healthy-controls. Furthermore, In1-ghrelin treatment/overexpression, and to a much lesser extent native-ghrelin, increased aggressiveness features (cell-proliferation, migration and PSA secretion) of NP and PCa cells. Consistently, nude-mice injected with PC-3-cells stably-transfected with In1-ghrelin, but not native-ghrelin, presented larger tumors. These effects were likely mediated by ERK1/2-signaling activation and involved altered expression of key oncogenes/tumor suppressor genes. Finally, In1-ghrelin silencing reduced cell-proliferation and PSA secretion from PCa cells. Conclusions Altogether, our results indicate that In1-ghrelin levels (in tissue) and circulating levels (in plasma) are increased in PCa where it can regulate key pathophysiological processes, thus suggesting that In1-ghrelin may represent a novel biomarker and a new therapeutic target in PCa. Electronic supplementary material The online version of this article (doi:10.1186/s12943-017-0713-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel Hormaechea-Agulla
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Manuel D Gahete
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Juan M Jiménez-Vacas
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Enrique Gómez-Gómez
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Alejandro Ibáñez-Costa
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Fernando L-López
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - Esther Rivero-Cortés
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - André Sarmento-Cabral
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,CIBERobn, Córdoba, Spain.,ceiA3, Córdoba, Spain
| | - José Valero-Rosa
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Julia Carrasco-Valiente
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Rafael Sánchez-Sánchez
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Anatomical Pathology Service, HURS/IMIBIC, Córdoba, Spain
| | - Rosa Ortega-Salas
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Anatomical Pathology Service, HURS/IMIBIC, Córdoba, Spain
| | - María M Moreno
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Anatomical Pathology Service, HURS/IMIBIC, Córdoba, Spain
| | | | - Steve M Swanson
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
| | | | - María J Requena
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain.,Reina Sofia University Hospital (HURS), Córdoba, Spain.,Urology Service, HURS/IMIBIC, Córdoba, Spain
| | - Justo P Castaño
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain. .,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain. .,Reina Sofia University Hospital (HURS), Córdoba, Spain. .,CIBERobn, Córdoba, Spain. .,ceiA3, Córdoba, Spain.
| | - Raúl M Luque
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), Córdoba, Spain. .,Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain. .,Reina Sofia University Hospital (HURS), Córdoba, Spain. .,CIBERobn, Córdoba, Spain. .,ceiA3, Córdoba, Spain.
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11
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Hassouna R, Grouselle D, Chiappetta G, Lipecka J, Fiquet O, Tomasetto C, Vinh J, Epelbaum J, Tolle V. Combination of Selective Immunoassays and Mass Spectrometry to Characterize Preproghrelin-Derived Peptides in Mouse Tissues. Front Neurosci 2017; 11:211. [PMID: 28473748 PMCID: PMC5397466 DOI: 10.3389/fnins.2017.00211] [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: 01/30/2017] [Accepted: 03/29/2017] [Indexed: 11/13/2022] Open
Abstract
Preproghrelin is a prohormone producing several preproghrelin-derived peptides with structural and functional heterogeneity: acyl ghrelin (AG), desacyl ghrelin (DAG), and obestatin. The absence of selective and reliable assays to measure these peptides simultaneously in biological samples has been a limitation to assess their real proportions in tissues and plasma in physiological and pathological conditions. We aimed at reliably measure the ratio between the different preproghrelin-derived peptides in murine tissues using selective immunoassays combined with a highly sensitive mass spectrometry method. AG-, DAG-, and obestatin-immunopositive fractions from the gastrointestinal tract of adult wild-type and ghrelin-deficient mice were processed for analysis by mass spectrometry (MS) with a Triple Quadrupole mass spectrometer. We found that DAG was predominant in mouse plasma, however it only represented 50% of total ghrelin (AG+DAG) production in the stomach and duodenum. Obestatin plasma levels accounted for about 30% of all circulating preproghrelin-derived peptides, however, it represented <1% of total preproghrelin-derived peptides production (AG+DAG+Obestatin) in the stomach. Assays were validated in ghrelin-deficient mice since neither ghrelin nor obestatin immunoreactivities were detected in their stomach, duodenum nor plasma. MS analyses confirmed that obestatin-immunoreactivity in stomach corresponded to the C-terminal amidated form of the peptide but not to des(1-10)-obestatin, nor to obestatin-Gly. In conclusion, specificity of ghrelin and obestatin immunoreactivities in gastrointestinal tissues using selective immunoassays was validated by MS. Obestatin was less abundant than AG or DAG in these tissues. Whether this is due to inefficient processing rate of preproghrelin into mature obestatin in gastrointestinal mouse tissues remains elusive.
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Affiliation(s)
- Rim Hassouna
- Centre de Psychiatrie et Neurosciences, UMR-S 894 Institut National de la Santé et de la Recherche Médicale, Université Paris Descartes, Sorbonne Paris CitéParis, France.,Department of Pediatrics, Naomi Berrie Diabetes Center, Columbia University Medical CenterNew York, NY, USA
| | - Dominique Grouselle
- Centre de Psychiatrie et Neurosciences, UMR-S 894 Institut National de la Santé et de la Recherche Médicale, Université Paris Descartes, Sorbonne Paris CitéParis, France
| | - Giovanni Chiappetta
- ESPCI Paris, PSL Research University, Spectrométrie de Masse Biologique et Protéomique (SMPB), CNRS USR 3149Paris, France
| | - Joanna Lipecka
- Centre de Psychiatrie et Neurosciences, UMR-S 894 Institut National de la Santé et de la Recherche Médicale, Université Paris Descartes, Sorbonne Paris CitéParis, France
| | - Oriane Fiquet
- Centre de Psychiatrie et Neurosciences, UMR-S 894 Institut National de la Santé et de la Recherche Médicale, Université Paris Descartes, Sorbonne Paris CitéParis, France
| | - Catherine Tomasetto
- UMR-7104 Centre Nationnal de la Recherche Scientifique/U596, Institut National de la Santé et de la Recherche Médicale, Institut de génétique et de biologie moléculaire et cellulaire, Université de StrasbourgIllkirch, France
| | - Joëlle Vinh
- ESPCI Paris, PSL Research University, Spectrométrie de Masse Biologique et Protéomique (SMPB), CNRS USR 3149Paris, France
| | - Jacques Epelbaum
- Centre de Psychiatrie et Neurosciences, UMR-S 894 Institut National de la Santé et de la Recherche Médicale, Université Paris Descartes, Sorbonne Paris CitéParis, France.,UMR 7179 Centre Nationnal de la Recherche Scientifique, MNHN, Adaptive Mechanism and Evolution (MECADEV)Brunoy, France
| | - Virginie Tolle
- Centre de Psychiatrie et Neurosciences, UMR-S 894 Institut National de la Santé et de la Recherche Médicale, Université Paris Descartes, Sorbonne Paris CitéParis, France
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12
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Grönberg M, Ahlin C, Naeser Y, Janson ET, Holmberg L, Fjällskog ML. Ghrelin is a prognostic marker and a potential therapeutic target in breast cancer. PLoS One 2017; 12:e0176059. [PMID: 28419141 PMCID: PMC5395214 DOI: 10.1371/journal.pone.0176059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 04/04/2017] [Indexed: 12/26/2022] Open
Abstract
Ghrelin and obestatin are gastrointestinal peptides, encoded by the same preproghrelin gene. Both are expressed in breast cancer tissue and ghrelin has been implicated in breast cancer tumorigenesis. Despite recent advances in breast cancer management the need for new prognostic markers and potential therapeutic targets in breast cancer remains high. We studied the prognostic impact of ghrelin and obestatin in women with node negative breast cancer. Within a cohort of women with breast cancer with tumor size ≤ 50 mm, no lymph node metastases and no initiation of adjuvant chemotherapy, 190 women were identified who died from breast cancer and randomly selected 190 women alive at the corresponding time as controls. Tumor tissues were immunostained with antibodies versus the peptides. Ghrelin expression was associated with better breast cancer specific survival in univariate analyses (OR 0.55, 95% CI 0.36–0.84) and in multivariate models, adjusted for endocrine treatment and age (OR 0.57, 95% CI 0.36–0.89). Obestatin expression was non-informative (OR 1.2, 95% CI 0.60–2.46). Ghrelin expression is independent prognostic factor for breast cancer death in node negative patients—halving the risk for dying of breast cancer. Our data implies that ghrelin could be a potential therapeutic target in breast cancer treatment.
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Affiliation(s)
- Malin Grönberg
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden
- * E-mail:
| | - Cecilia Ahlin
- Department of Oncology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Ylva Naeser
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden
| | - Eva Tiensuu Janson
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden
| | - Lars Holmberg
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Faculty of Life Sciences and Medicine, King’s College London, London, United Kingdom
| | - Marie-Louise Fjällskog
- Department of Medical Sciences, Section of Endocrine Oncology, Uppsala University, Uppsala, Sweden
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13
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Seim I, Jeffery PL, Thomas PB, Walpole CM, Maugham M, Fung JNT, Yap PY, O’Keeffe AJ, Lai J, Whiteside EJ, Herington AC, Chopin LK. Multi-species sequence comparison reveals conservation of ghrelin gene-derived splice variants encoding a truncated ghrelin peptide. Endocrine 2016; 52:609-17. [PMID: 26792793 PMCID: PMC4879156 DOI: 10.1007/s12020-015-0848-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 12/23/2015] [Indexed: 12/19/2022]
Abstract
The peptide hormone ghrelin is a potent orexigen produced predominantly in the stomach. It has a number of other biological actions, including roles in appetite stimulation, energy balance, the stimulation of growth hormone release and the regulation of cell proliferation. Recently, several ghrelin gene splice variants have been described. Here, we attempted to identify conserved alternative splicing of the ghrelin gene by cross-species sequence comparisons. We identified a novel human exon 2-deleted variant and provide preliminary evidence that this splice variant and in1-ghrelin encode a C-terminally truncated form of the ghrelin peptide, termed minighrelin. These variants are expressed in humans and mice, demonstrating conservation of alternative splicing spanning 90 million years. Minighrelin appears to have similar actions to full-length ghrelin, as treatment with exogenous minighrelin peptide stimulates appetite and feeding in mice. Forced expression of the exon 2-deleted preproghrelin variant mirrors the effect of the canonical preproghrelin, stimulating cell proliferation and migration in the PC3 prostate cancer cell line. This is the first study to characterise an exon 2-deleted preproghrelin variant and to demonstrate sequence conservation of ghrelin gene-derived splice variants that encode a truncated ghrelin peptide. This adds further impetus for studies into the alternative splicing of the ghrelin gene and the function of novel ghrelin peptides in vertebrates.
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Affiliation(s)
- Inge Seim
- />Comparative and Endocrine Biology Laboratory, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Penny L. Jeffery
- />Comparative and Endocrine Biology Laboratory, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Patrick B. Thomas
- />Comparative and Endocrine Biology Laboratory, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Carina M. Walpole
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Michelle Maugham
- />Comparative and Endocrine Biology Laboratory, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Jenny N. T. Fung
- />Molecular Epidemiology Laboratory, QIMR Berghofer Medical Research Institute, Herston, QLD 4006 Australia
| | - Pei-Yi Yap
- />Signal Transduction Laboratory, QIMR Berghofer Medical Research Institute, Herston, QLD 4006 Australia
| | - Angela J. O’Keeffe
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - John Lai
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Eliza J. Whiteside
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Adrian C. Herington
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
| | - Lisa K. Chopin
- />Comparative and Endocrine Biology Laboratory, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Ghrelin Research Group, Translational Research Institute-Institute of Health and Biomedical Innovation (TRI-IHBI), Queensland University of Technology, Woolloongabba, QLD 4102 Australia
- />Australian Prostate Cancer Research Centre, Queensland, Princess Alexandra Hospital, Queensland University of Technology, Woolloongabba, QLD 4102 Australia
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14
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Steyn FJ, Tolle V, Chen C, Epelbaum J. Neuroendocrine Regulation of Growth Hormone Secretion. Compr Physiol 2016; 6:687-735. [PMID: 27065166 DOI: 10.1002/cphy.c150002] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This article reviews the main findings that emerged in the intervening years since the previous volume on hormonal control of growth in the section on the endocrine system of the Handbook of Physiology concerning the intra- and extrahypothalamic neuronal networks connecting growth hormone releasing hormone (GHRH) and somatostatin hypophysiotropic neurons and the integration between regulators of food intake/metabolism and GH release. Among these findings, the discovery of ghrelin still raises many unanswered questions. One important event was the application of deconvolution analysis to the pulsatile patterns of GH secretion in different mammalian species, including Man, according to gender, hormonal environment and ageing. Concerning this last phenomenon, a great body of evidence now supports the role of an attenuation of the GHRH/GH/Insulin-like growth factor-1 (IGF-1) axis in the control of mammalian aging.
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Affiliation(s)
- Frederik J Steyn
- University of Queensland Centre for Clinical Research and the School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Virginie Tolle
- Unité Mixte de Recherche en Santé 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
| | - Jacques Epelbaum
- University of Queensland Centre for Clinical Research and the School of Biomedical Sciences, University of Queensland, St. Lucia, Brisbane, Queensland, Australia
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15
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Kraus D, Reckenbeil J, Wenghoefer M, Stark H, Frentzen M, Allam JP, Novak N, Frede S, Götz W, Probstmeier R, Meyer R, Winter J. Ghrelin promotes oral tumor cell proliferation by modifying GLUT1 expression. Cell Mol Life Sci 2016; 73:1287-99. [PMID: 26407611 PMCID: PMC11108541 DOI: 10.1007/s00018-015-2048-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 09/11/2015] [Accepted: 09/17/2015] [Indexed: 12/13/2022]
Abstract
In our study, ghrelin was investigated with respect to its capacity on proliferative effects and molecular correlations on oral tumor cells. The presence of all molecular components of the ghrelin system, i.e., ghrelin and its receptors, was analyzed and could be detected using real-time PCR and immunohistochemistry. To examine cellular effects caused by ghrelin and to clarify downstream-regulatory mechanisms, two different oral tumor cell lines (BHY and HN) were used in cell culture experiments. Stimulation of either cell line with ghrelin led to a significantly increased proliferation. Signal transduction occurred through phosphorylation of GSK-3β and nuclear translocation of β-catenin. This effect could be inhibited by blocking protein kinase A. Glucose transporter1 (GLUT1), as an important factor for delivering sufficient amounts of glucose to tumor cells having high requirements for this carbohydrate (Warburg effect) was up-regulated by exogenous and endogenous ghrelin. Silencing intracellular ghrelin concentrations using siRNA led to a significant decreased expression of GLUT1 and proliferation. In conclusion, our study describes the role for the appetite-stimulating peptide hormone ghrelin in oral cancer proliferation under the particular aspect of glucose uptake: (1) tumor cells are a source of ghrelin. (2) Ghrelin affects tumor cell proliferation through autocrine and/or paracrine activity. (3) Ghrelin modulates GLUT1 expression and thus indirectly enhances tumor cell proliferation. These findings are of major relevance, because glucose uptake is assumed to be a promising target for cancer treatment.
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Affiliation(s)
- Dominik Kraus
- Department of Prosthodontics, Preclinical Education, and Material Science, University of Bonn, Bonn, Germany
| | - Jan Reckenbeil
- Department of Prosthodontics, Preclinical Education, and Material Science, University of Bonn, Bonn, Germany
| | - Matthias Wenghoefer
- Department of Oral and Maxillofacial Plastic Surgery, University of Bonn, Bonn, Germany
| | - Helmut Stark
- Department of Prosthodontics, Preclinical Education, and Material Science, University of Bonn, Bonn, Germany
| | - Matthias Frentzen
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany
| | - Jean-Pierre Allam
- Department of Dermatology and Allergy, University of Bonn, Bonn, Germany
| | - Natalija Novak
- Department of Dermatology and Allergy, University of Bonn, Bonn, Germany
| | - Stilla Frede
- Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Bonn, Germany
| | - Werner Götz
- Department of Orthodontics, University of Bonn, Bonn, Germany
| | | | - Rainer Meyer
- Institute of Physiology II, University of Bonn, Bonn, Germany
| | - Jochen Winter
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany.
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16
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Luque RM, Sampedro-Nuñez M, Gahete MD, Ramos-Levi A, Ibáñez-Costa A, Rivero-Cortés E, Serrano-Somavilla A, Adrados M, Culler MD, Castaño JP, Marazuela M. In1-ghrelin, a splice variant of ghrelin gene, is associated with the evolution and aggressiveness of human neuroendocrine tumors: Evidence from clinical, cellular and molecular parameters. Oncotarget 2015; 6:19619-33. [PMID: 26124083 PMCID: PMC4637309 DOI: 10.18632/oncotarget.4316] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Accepted: 06/06/2015] [Indexed: 01/27/2023] Open
Abstract
Ghrelin system comprises a complex family of peptides, receptors (GHSRs), and modifying enzymes [e.g. ghrelin-O-acyl-transferase (GOAT)] that control multiple pathophysiological processes. Aberrant alternative splicing is an emerging cancer hallmark that generates altered proteins with tumorigenic capacity. Indeed, In1-ghrelin and truncated-GHSR1b splicing variants can promote development/progression of certain endocrine-related cancers. Here, we determined the expression levels of key ghrelin system components in neuroendocrine tumor (NETs) and explored their potential functional role. Twenty-six patients with NETs were prospectively/retrospectively studied [72 samples from primary and metastatic tissues (30 normal/42 tumors)] and clinical data were obtained. The role of In1-ghrelin in aggressiveness was studied in vitro using NET cell lines (BON-1/QGP-1). In1-ghrelin, GOAT and GHSR1a/1b expression levels were elevated in tumoral compared to normal/adjacent tissues. Moreover, In1-ghrelin, GOAT, and GHSR1b expression levels were positively correlated within tumoral, but not within normal/adjacent samples, and were higher in patients with progressive vs. with stable/cured disease. Finally, In1-ghrelin increased aggressiveness (e.g. proliferation/migration) of NET cells. Altogether, our data strongly suggests a potential implication of ghrelin system in the pathogenesis and/or clinical outcome of NETs, and warrant further studies on their possible value for the future development of molecular biomarkers with diagnostic/prognostic/therapeutic value.
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Affiliation(s)
- Raul M Luque
- Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba Hospital Universitario Reina Sofía, Instituto Maimónides de Investigación Biomèdica de Córdoba (IMIBIC), Campus de Excelencia Internacional Agroalimentario (ceiA3), CIBER Fisiopatología de la Obesidad y Nutricón (CIBERObn), Córdoba, España
| | - Miguel Sampedro-Nuñez
- Servicio de Endocrinología y Nutrición, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria Princesa, Madrid, España
| | - Manuel D Gahete
- Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba Hospital Universitario Reina Sofía, Instituto Maimónides de Investigación Biomèdica de Córdoba (IMIBIC), Campus de Excelencia Internacional Agroalimentario (ceiA3), CIBER Fisiopatología de la Obesidad y Nutricón (CIBERObn), Córdoba, España
| | - Ana Ramos-Levi
- Servicio de Endocrinología y Nutrición, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria Princesa, Madrid, España
| | - Alejandro Ibáñez-Costa
- Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba Hospital Universitario Reina Sofía, Instituto Maimónides de Investigación Biomèdica de Córdoba (IMIBIC), Campus de Excelencia Internacional Agroalimentario (ceiA3), CIBER Fisiopatología de la Obesidad y Nutricón (CIBERObn), Córdoba, España
| | - Esther Rivero-Cortés
- Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba Hospital Universitario Reina Sofía, Instituto Maimónides de Investigación Biomèdica de Córdoba (IMIBIC), Campus de Excelencia Internacional Agroalimentario (ceiA3), CIBER Fisiopatología de la Obesidad y Nutricón (CIBERObn), Córdoba, España
| | - Ana Serrano-Somavilla
- Servicio de Endocrinología y Nutrición, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria Princesa, Madrid, España
| | - Magdalena Adrados
- Servicio de Patología, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria Princesa, Madrid, España
| | | | - Justo P Castaño
- Departamento de Biología Celular, Fisiología e Inmunología, Universidad de Córdoba Hospital Universitario Reina Sofía, Instituto Maimónides de Investigación Biomèdica de Córdoba (IMIBIC), Campus de Excelencia Internacional Agroalimentario (ceiA3), CIBER Fisiopatología de la Obesidad y Nutricón (CIBERObn), Córdoba, España
| | - Mónica Marazuela
- Servicio de Endocrinología y Nutrición, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Instituto de Investigación Sanitaria Princesa, Madrid, España
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Seim I, Jeffery PL, Herington AC, Chopin LK. Comparative analysis reveals loss of the appetite-regulating peptide hormone ghrelin in falcons. Gen Comp Endocrinol 2015; 216:98-102. [PMID: 25500363 DOI: 10.1016/j.ygcen.2014.11.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 11/10/2014] [Accepted: 11/21/2014] [Indexed: 12/22/2022]
Abstract
Ghrelin and leptin are key peripherally secreted appetite-regulating hormones in vertebrates. Here we consider the ghrelin gene (GHRL) of birds (class Aves), where it has been reported that ghrelin inhibits rather than augments feeding. Thirty-one bird species were compared, revealing that most species harbour a functional copy of GHRL and the coding region for its derived peptides ghrelin and obestatin. We provide evidence for loss of GHRL in saker and peregrine falcons, and this is likely to result from the insertion of an ERVK retrotransposon in intron 0. We hypothesise that the loss of anorexigenic ghrelin is a predatory adaptation that results in increased food-seeking behaviour and feeding in falcons.
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Affiliation(s)
- Inge Seim
- Ghrelin Research Group, Translational Research Institute - Institute of Health and Biomedical Innovation, Queensland University of Technology, 37 Kent St., Woolloongabba, Queensland 4102, Australia; Australian Prostate Cancer Research Centre - Queensland, Queensland University of Technology and Princess Alexandra Hospital, Woolloongabba, Queensland 4102, Australia
| | - Penny L Jeffery
- Ghrelin Research Group, Translational Research Institute - Institute of Health and Biomedical Innovation, Queensland University of Technology, 37 Kent St., Woolloongabba, Queensland 4102, Australia; Australian Prostate Cancer Research Centre - Queensland, Queensland University of Technology and Princess Alexandra Hospital, Woolloongabba, Queensland 4102, Australia
| | - Adrian C Herington
- Ghrelin Research Group, Translational Research Institute - Institute of Health and Biomedical Innovation, Queensland University of Technology, 37 Kent St., Woolloongabba, Queensland 4102, Australia; Australian Prostate Cancer Research Centre - Queensland, Queensland University of Technology and Princess Alexandra Hospital, Woolloongabba, Queensland 4102, Australia
| | - Lisa K Chopin
- Ghrelin Research Group, Translational Research Institute - Institute of Health and Biomedical Innovation, Queensland University of Technology, 37 Kent St., Woolloongabba, Queensland 4102, Australia; Australian Prostate Cancer Research Centre - Queensland, Queensland University of Technology and Princess Alexandra Hospital, Woolloongabba, Queensland 4102, Australia.
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Ibáñez-Costa A, Gahete MD, Rivero-Cortés E, Rincón-Fernández D, Nelson R, Beltrán M, de la Riva A, Japón MA, Venegas-Moreno E, Gálvez MÁ, García-Arnés JA, Soto-Moreno A, Morgan J, Tsomaia N, Culler MD, Dieguez C, Castaño JP, Luque RM. In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features. Sci Rep 2015; 5:8714. [PMID: 25737012 PMCID: PMC4649711 DOI: 10.1038/srep08714] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 02/02/2015] [Indexed: 01/26/2023] Open
Abstract
Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n = 11) and pituitary adenomas (n = 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas comparedwith normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24–72 h) increased GH and ACTH secretion, Ca2+ and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors.
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Affiliation(s)
- Alejandro Ibáñez-Costa
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - Manuel D Gahete
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - Esther Rivero-Cortés
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - David Rincón-Fernández
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | | | - Manuel Beltrán
- Department of Pathology, Puerta del Mar University Hospital, Cádiz
| | - Andrés de la Riva
- Service of Neurosurgery, Hospital Universitario Reina Sofia, 14004 Córdoba, Spain
| | - Miguel A Japón
- Department of Pathology, Hospital Universitario Virgen del Rocío, 41013 Seville, Spain
| | - Eva Venegas-Moreno
- Metabolism and Nutrition Unit, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla (IBIS), 41013 Seville, Spain
| | - Ma Ángeles Gálvez
- Service of Endocrinology and Nutrition, Hospital Universitario Reina Sofia, and Instituto Maimónides de Investigación Biomédica de Córdoba, 14004 Córdoba, Spain
| | - Juan A García-Arnés
- Department of Endocrinology and Nutrition, Carlos Haya Hospital, 29010 Málaga, Spain
| | - Alfonso Soto-Moreno
- Metabolism and Nutrition Unit, Hospital Universitario Virgen del Rocío, Instituto de Biomedicina de Sevilla (IBIS), 41013 Seville, Spain
| | | | - Natia Tsomaia
- IPSEN Bioscience, Cambridge, 02142 Massachusetts, USA
| | | | - Carlos Dieguez
- Department of Physiology, University of Santiago de Compostela, and CIBER Fisiopatología de la Obesidad y Nutrición, 15782 Santiago de Compostela, Spain
| | - Justo P Castaño
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
| | - Raúl M Luque
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Hospital Universitario Reina Sofia; CIBER Fisiopatología de la Obesidad y Nutrición; and Campus de Excelencia Internacional Agroalimentario (ceiA3), 14014 Córdoba, Spain
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19
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Menzies M, Seim I, Josh P, Nagaraj SH, Lees M, Walpole C, Chopin LK, Colgrave M, Ingham A. Cloning and tissue distribution of novel splice variants of the ovine ghrelin gene. BMC Vet Res 2014; 10:211. [PMID: 25350131 PMCID: PMC4172912 DOI: 10.1186/s12917-014-0211-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 08/29/2014] [Indexed: 12/15/2022] Open
Abstract
Background The ghrelin axis is involved in the regulation of metabolism, energy balance, and the immune, cardiovascular and reproductive systems. The manipulation of this axis has potential for improving economically valuable traits in production animals, and polymorphisms in the ghrelin (GHRL) and ghrelin receptor (GHSR) genes have been associated with growth and carcass traits. Here we investigate the structure and expression of the ghrelin gene (GHRL) in sheep, Ovis aries. Results We identify two ghrelin mRNA isoforms, which we have designated Δex2 preproghrelin and Δex2,3 preproghrelin. Expression of Δex2,3 preproghrelin is likely to be restricted to ruminants, and would encode truncated ghrelin and a novel C-terminal peptide. Both Δex2 preproghrelin and canonical preproghrelin mRNA isoforms were expressed in a range of tissues. Expression of the Δex2,3 preproghrelin isoform, however, was restricted to white blood cells (WBC; where the wild-type preproghrelin isoform is not co-expressed), and gastrointestinal tissues. Expression of Δex2 preproghrelin and Δex2,3 preproghrelin mRNA was elevated in white blood cells in response to parasitic worm (helminth) infection in genetically susceptible sheep, but not in resistant sheep. Conclusions The restricted expression of the novel preproghrelin variants and their distinct WBC expression pattern during parasite infection may indicate a novel link between the ghrelin axis and metabolic and immune function in ruminants.
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Perret J, De Vriese C, Delporte C. Polymorphisms for ghrelin with consequences on satiety and metabolic alterations. Curr Opin Clin Nutr Metab Care 2014; 17:306-11. [PMID: 24870813 DOI: 10.1097/mco.0000000000000072] [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: 12/20/2022]
Abstract
PURPOSE OF REVIEW To understand the current trend of ghrelin genetic variations on the control of satiety, eating behaviours, obesity, and metabolic alterations, and its development over the last 18 months. RECENT FINDINGS Several polymorphisms of the ghrelin gene, its receptor gene and ghrelin's acylating enzyme, ghrelin O-acyl transferase, have been identified and studied over the last decade in relation to control of satiety, obesity, eating behaviours, metabolic syndrome, glucose homeostasis, and type 2 diabetes. However, the effects described are either small or nonsignificant and often subjected to contradictory conclusions between studies. In the last 18 months, several of these areas of investigations have been revisited under more controlled conditions or have been subjected to meta-analysis. SUMMARY The effects of ghrelin gene polymorphism, is a complex area of investigation, due to ghrelin's interplay with a host of various factors part of an integrative network. However, taken together, results suggest that there are no or nonsignificant effects of the common genetic variants. A better understanding of the network, probably by a systems biology type approach, will be necessary to assign the exact role played by gene polymorphism of the component of the ghrelin axis.
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Affiliation(s)
- Jason Perret
- aLaboratory of Pathophysiological and Nutritional Biochemistry bLaboratory of Pharmaceutics and Biopharmaceutics, Université Libre de Bruxelles, Brussels, Belgium
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21
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Gahete MD, Rincón-Fernández D, Villa-Osaba A, Hormaechea-Agulla D, Ibáñez-Costa A, Martínez-Fuentes AJ, Gracia-Navarro F, Castaño JP, Luque RM. Ghrelin gene products, receptors, and GOAT enzyme: biological and pathophysiological insight. J Endocrinol 2014; 220:R1-24. [PMID: 24194510 DOI: 10.1530/joe-13-0391] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ghrelin is a 28-amino acid acylated hormone, highly expressed in the stomach, which binds to its cognate receptor (GHSR1a) to regulate a plethora of relevant biological processes, including food intake, energy balance, hormonal secretions, learning, inflammation, etc. However, ghrelin is, in fact, the most notorious component of a complex, intricate regulatory system comprised of a growing number of alternative peptides (e.g. obestatin, unacylated ghrelin, and In1-ghrelin, etc.), known (GHSRs) and, necessarily unknown receptors, as well as modifying enzymes (e.g. ghrelin-O-acyl-transferase), which interact among them as well as with other regulatory systems in order to tightly modulate key (patho)-physiological processes. This multiplicity of functions and versatility of the ghrelin system arise from a dual, genetic and functional, complexity. Importantly, a growing body of evidence suggests that dysregulation in some of the components of the ghrelin system can lead to or influence the development and/or progression of highly concerning pathologies such as endocrine-related tumors, inflammatory/cardiovascular diseases, and neurodegeneration, wherein these altered components could be used as diagnostic, prognostic, or therapeutic targets. In this context, the aim of this review is to integrate and comprehensively analyze the multiple components and functions of the ghrelin system described to date in order to define and understand its biological and (patho)-physiological significance.
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Affiliation(s)
- Manuel D Gahete
- Department of Cell Biology, Physiology and Immunology, Campus Universitario de Rabanales, Edificio Severo Ochoa (C6), Planta 3, University of Córdoba, 14014-Córdoba; Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba; Reina Sofia University Hospital, Córdoba; and CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Córdoba, Spain
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22
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Ghrelin and its interactions with growth hormone, leptin and orexins: implications for the sleep-wake cycle and metabolism. Sleep Med Rev 2013; 18:89-97. [PMID: 23816458 DOI: 10.1016/j.smrv.2013.04.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 04/11/2013] [Accepted: 04/12/2013] [Indexed: 12/16/2022]
Abstract
Several studies have shown that ghrelin administration promotes wakefulness in rodents, while in human males it induces sleep but has no effect in women. Ghrelin also plays an important role in metabolism and appetite regulation, and as described in this review may participate in the energy balance during sleep. In this review, we summarize some of the effects induced by ghrelin administration on the sleep-wake cycle in relation to the effects of other hormones, such as growth hormone, leptin, and orexin. Finally we discuss the relationship between sleep deprivation, obesity and ghrelin secretion pattern.
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23
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Seim I, Lubik AA, Lehman ML, Tomlinson N, Whiteside EJ, Herington AC, Nelson CC, Chopin LK. Cloning of a novel insulin-regulated ghrelin transcript in prostate cancer. J Mol Endocrinol 2013; 50:179-91. [PMID: 23267039 DOI: 10.1530/jme-12-0150] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ghrelin is a multifunctional hormone, with roles in stimulating appetite and regulating energy balance, insulin secretion and glucose homoeostasis. The ghrelin gene locus (GHRL) is highly complex and gives rise to a range of novel transcripts derived from alternative first exons and internally spliced exons. The wild-type transcript encodes a 117 amino acid preprohormone that is processed to yield the 28 amino acid peptide ghrelin. Here, we identified insulin-responsive transcription corresponding to cryptic exons in intron 2 of the human ghrelin gene. A transcript, termed in2c-ghrelin (intron 2-cryptic), was cloned from the testis and the LNCaP prostate cancer cell line. This transcript may encode an 83 amino acid preproghrelin isoform that codes for ghrelin, but not obestatin. It is expressed in a limited number of normal tissues and in tumours of the prostate, testis, breast and ovary. Finally, we confirmed that in2c-ghrelin transcript expression, as well as the recently described in1-ghrelin transcript, is significantly upregulated by insulin in cultured prostate cancer cells. Metabolic syndrome and hyperinsulinaemia have been associated with prostate cancer risk and progression. This may be particularly significant after androgen deprivation therapy for prostate cancer, which induces hyperinsulinaemia, and this could contribute to castrate-resistant prostate cancer growth. We have previously demonstrated that ghrelin stimulates prostate cancer cell line proliferation in vitro. This study is the first description of insulin regulation of a ghrelin transcript in cancer and should provide further impetus for studies into the expression, regulation and function of ghrelin gene products.
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Affiliation(s)
- Inge Seim
- Institute of Health and Biomedical Innovation (IHBI), Queensland University of Technology, Kelvin Grove, Brisbane, Queensland 4059, Australia
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Chopin LK, Seim I, Walpole CM, Herington AC. The ghrelin axis--does it have an appetite for cancer progression? Endocr Rev 2012; 33:849-91. [PMID: 22826465 DOI: 10.1210/er.2011-1007] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ghrelin, the endogenous ligand for the GH secretagogue receptor (GHSR), is a peptide hormone with diverse physiological roles. Ghrelin regulates GH release, appetite and feeding, gut motility, and energy balance and also has roles in the cardiovascular, immune, and reproductive systems. Ghrelin and the GHSR are expressed in a wide range of normal and tumor tissues, and a fluorescein-labeled, truncated form of ghrelin is showing promise as a biomarker for prostate cancer. Plasma ghrelin levels are generally inversely related to body mass index and are unlikely to be useful as a biomarker for cancer, but may be useful as a marker for cancer cachexia. Some single nucleotide polymorphisms in the ghrelin and GHSR genes have shown associations with cancer risk; however, larger studies are required. Ghrelin regulates processes associated with cancer, including cell proliferation, apoptosis, cell migration, cell invasion, inflammation, and angiogenesis; however, the role of ghrelin in cancer is currently unclear. Ghrelin has predominantly antiinflammatory effects and may play a role in protecting against cancer-related inflammation. Ghrelin and its analogs show promise as treatments for cancer-related cachexia. Further studies using in vivo models are required to determine whether ghrelin has a role in cancer progression.
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Affiliation(s)
- Lisa K Chopin
- Ghrelin Research Group, Institute of Health and Biomedical Innovation, Queensland University of Technology and Australian Prostate Cancer Research Centre-Queensland, Brisbane, Queensland 4001, Australia.
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Baragli A, Lanfranco F, Allasia S, Granata R, Ghigo E. Neuroendocrine and metabolic activities of ghrelin gene products. Peptides 2011; 32:2323-32. [PMID: 22056513 DOI: 10.1016/j.peptides.2011.10.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 10/03/2011] [Accepted: 10/25/2011] [Indexed: 12/15/2022]
Abstract
Acylated ghrelin (AG) is a 28 amino acid gastric peptide a natural ligand for the growth hormone secretagogue (GHS) receptor type 1a (GHS-R1a), endowed with GH-secreting and orexigenic properties. Besides, ghrelin exerts several peripheral metabolic actions, including modulation of glucose homeostasis and stimulation of adipogenesis. Notably, AG administration causes hyperglycemia in rodents as in humans. Ghrelin pleiotropy is supported by a widespread expression of the ghrelin gene, of GHS-R1a and other unknown ghrelin binding sites. The existence of alternative receptors for AG, of several natural ligands for GHS-R1a and of acylation-independent ghrelin non-neuroendocrine activities, suggests that there might be a complex 'ghrelin system' not yet completely explored. Moreover, the patho-physiological implications of unacylated ghrelin (UAG), and obestatin (Ob), the other two ghrelin gene-derived peptides, need to be clarified. Within the next few years, we may better understand the 'ghrelin system', where we might envisage clinical applications.
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Affiliation(s)
- Alessandra Baragli
- Laboratory of Molecular and Cellular Endocrinology, Division of Endocrinology, Department of Internal Medicine, University of Turin, Turin, Italy.
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Zizzari P, Hassouna R, Grouselle D, Epelbaum J, Tolle V. Physiological roles of preproghrelin-derived peptides in GH secretion and feeding. Peptides 2011; 32:2274-82. [PMID: 21530598 DOI: 10.1016/j.peptides.2011.04.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 04/04/2011] [Accepted: 04/07/2011] [Indexed: 12/26/2022]
Abstract
Among the factors playing a crucial role in the regulation of energy metabolism, gastro-intestinal peptides are essential signals to maintain energy homeostasis as they relay to the central nervous system the informations about the nutritional status of the body. Among these factors, preproghrelin is a unique prohormone as it encodes ghrelin, a powerful GH secretagogue and the only orexigenic signal from the gastrointestinal tract and obestatin, a proposed functional ghrelin antagonist. These preproghrelin-derived peptides may contribute to balance energy intake, metabolism and body composition by regulating the activity of the GH/IGF-1 axis and appetite. Whereas the contribution of ghrelin has been well characterized, the role of the more recently identified obestatin, in this regulatory process is still controversial. In this chapter, we describe the contribution of these different preproghrelin-derived peptides and their receptors in the regulation of GH secretion and feeding. Data obtained from pharmacological approaches, mutant models and evaluation of the hormones in animal and human models are discussed.
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Affiliation(s)
- Philippe Zizzari
- UMR894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, 2 ter rue d'Alésia, 75014 Paris, France
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27
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Nishi Y, Yoh J, Hiejima H, Kojima M. Structures and molecular forms of the ghrelin-family peptides. Peptides 2011; 32:2175-82. [PMID: 21839128 DOI: 10.1016/j.peptides.2011.07.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 07/08/2011] [Accepted: 07/22/2011] [Indexed: 11/23/2022]
Abstract
Ghrelin is an acylated peptide hormone produced mainly from the stomach. The major active products of the ghrelin gene in the stomach of rats, mice and humans are 28-amino acid peptides acylated at the serine-3 position with an n-octanoyl group (C8:0), called simply ghrelin. However, recent studies have revealed that the ghrelin gene can generate a variety of bioactive molecules besides ghrelin. These include acyl forms of ghrelin other than C8:0-ghrelin (i.e., n-decanoyl ghrelin or n-decenoyl ghrelin), des-acyl ghrelin, obestatin and ghrelin-associated peptides originated from the ghrelin gene. This review surveys the structures of the ghrelin peptides and molecular forms of ghrelin gene-derived products, and summarizes the knowledge about the functions of these peptides, with an emphasis on the acyl forms of the ghrelin peptide.
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Affiliation(s)
- Yoshihiro Nishi
- Department of Physiology, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka 830-0011, Japan.
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Gahete MD, Córdoba-Chacón J, Hergueta-Redondo M, Martínez-Fuentes AJ, Kineman RD, Moreno-Bueno G, Luque RM, Castaño JP. A novel human ghrelin variant (In1-ghrelin) and ghrelin-O-acyltransferase are overexpressed in breast cancer: potential pathophysiological relevance. PLoS One 2011; 6:e23302. [PMID: 21829727 PMCID: PMC3150424 DOI: 10.1371/journal.pone.0023302] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 07/14/2011] [Indexed: 12/02/2022] Open
Abstract
The human ghrelin gene, which encodes the ghrelin and obestatin peptides, contains 5 exons (Ex), with Ex1-Ex4 encoding a 117 amino-acid (aa) preproprotein that is known to be processed to yield a 28-aa (ghrelin) and/or a 23-aa (obestatin) mature peptides, which possess biological activities in multiple tissues. However, the ghrelin gene also encodes additional peptides through alternative splicing or post-translational modifications. Indeed, we previously identified a spliced mRNA ghrelin variant in mouse (In2-ghrelin-variant), which is regulated in a tissue-dependent manner by metabolic status and may thus be of biological relevance. Here, we have characterized a new human ghrelin variant that contains Ex0-1, intron (In) 1, and Ex2 and lacks Ex3-4. This human In1-ghrelin variant would encode a new prepropeptide that conserves the first 12aa of native-ghrelin (including the Ser3-potential octanoylation site) but has a different C-terminal tail. Expression of In1-variant was detected in 22 human tissues and its levels were positively correlated with those of ghrelin-O-acyltransferase (GOAT; p = 0.0001) but not with native-ghrelin expression, suggesting that In1-ghrelin could be a primary substrate for GOAT in human tissues. Interestingly, levels of In1-ghrelin variant expression in breast cancer samples were 8-times higher than those of normal mammary tissue, and showed a strong correlation in breast tumors with GOAT (p = 0.0001), ghrelin receptor-type 1b (GHSR1b; p = 0.049) and cyclin-D3 (a cell-cycle inducer/proliferation marker; p = 0.009), but not with native-ghrelin or GHSR1a expression. Interestingly, In1-ghrelin variant overexpression increased basal proliferation of MDA-MB-231 breast cancer cells. Taken together, our results provide evidence that In1-ghrelin is a novel element of the ghrelin family with a potential pathophysiological role in breast cancer.
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Affiliation(s)
- Manuel D. Gahete
- Department of Cell Biology, Physiology and Immunology, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Hospital Universitario Reina Sofía, and CIBERobn Fisiopatología de la Obesidad y la Nutrición, Córdoba, Spain
| | - José Córdoba-Chacón
- Department of Cell Biology, Physiology and Immunology, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Hospital Universitario Reina Sofía, and CIBERobn Fisiopatología de la Obesidad y la Nutrición, Córdoba, Spain
| | - Marta Hergueta-Redondo
- Department of Biochemistry, Instituto de Investigaciones Biomédicas “Alberto Sols”, CSIC-UAM, Instituto de Investigación Sanitaria La Paz (IdiPAZ) and Fundación MD Anderson Internacional, Madrid, Spain
| | - Antonio J. Martínez-Fuentes
- Department of Cell Biology, Physiology and Immunology, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Hospital Universitario Reina Sofía, and CIBERobn Fisiopatología de la Obesidad y la Nutrición, Córdoba, Spain
| | - Rhonda D. Kineman
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois at Chicago, and Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois, United States of America
| | - Gema Moreno-Bueno
- Department of Biochemistry, Instituto de Investigaciones Biomédicas “Alberto Sols”, CSIC-UAM, Instituto de Investigación Sanitaria La Paz (IdiPAZ) and Fundación MD Anderson Internacional, Madrid, Spain
| | - Raúl M. Luque
- Department of Cell Biology, Physiology and Immunology, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Hospital Universitario Reina Sofía, and CIBERobn Fisiopatología de la Obesidad y la Nutrición, Córdoba, Spain
- * E-mail: (JPC); (RML)
| | - Justo P. Castaño
- Department of Cell Biology, Physiology and Immunology, Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), University of Córdoba, Hospital Universitario Reina Sofía, and CIBERobn Fisiopatología de la Obesidad y la Nutrición, Córdoba, Spain
- * E-mail: (JPC); (RML)
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Seim I, Josh P, Cunningham P, Herington A, Chopin L. Ghrelin axis genes, peptides and receptors: recent findings and future challenges. Mol Cell Endocrinol 2011; 340:3-9. [PMID: 21616122 DOI: 10.1016/j.mce.2011.05.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 05/04/2011] [Accepted: 05/09/2011] [Indexed: 12/15/2022]
Abstract
The ghrelin axis consists of the gene products of the ghrelin gene (GHRL), and their receptors, including the classical ghrelin receptor GHSR. While it is well-known that the ghrelin gene encodes the 28 amino acid ghrelin peptide hormone, it is now also clear that the locus encodes a range of other bioactive molecules, including novel peptides and non-coding RNAs. For many of these molecules, the physiological functions and cognate receptor(s) remain to be determined. Emerging research techniques, including proteogenomics, are likely to reveal further ghrelin axis-derived molecules. Studies of the role of ghrelin axis genes, peptides and receptors, therefore, promises to be a fruitful area of basic and clinical research in years to come.
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Affiliation(s)
- Inge Seim
- Queensland University of Technology, Brisbane, Queensland, Australia
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30
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Current world literature. Curr Opin Endocrinol Diabetes Obes 2011; 18:83-98. [PMID: 21178692 DOI: 10.1097/med.0b013e3283432fa7] [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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31
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De Vriese C, Perret J, Delporte C. Focus on the short- and long-term effects of ghrelin on energy homeostasis. Nutrition 2010; 26:579-84. [DOI: 10.1016/j.nut.2009.09.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 09/17/2009] [Indexed: 02/06/2023]
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