1
|
Singh J, Meena A, Luqman S. New frontiers in the design and discovery of therapeutics that target calcium ion signaling: a novel approach in the fight against cancer. Expert Opin Drug Discov 2023; 18:1379-1392. [PMID: 37655549 DOI: 10.1080/17460441.2023.2251887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 08/22/2023] [Indexed: 09/02/2023]
Abstract
INTRODUCTION The Ca2+ signaling toolkit is currently under investigation as a potential target for addressing the threat of cancer. A growing body of evidence suggests that calcium signaling plays a crucial role in promoting various aspects of cancer, including cell proliferation, progression, drug resistance, and migration-related activities. Consequently, focusing on these altered Ca2+ transporting proteins has emerged as a promising area of research for cancer treatment. AREAS COVERED This review highlights the existing research on the role of Ca2+-transporting proteins in cancer progression. It discusses the current studies evaluating Ca2+ channel/transporter/pump blockers, inhibitors, or regulators as potential anticancer drugs. Additionally, the review addresses specific gaps in our understanding of the field that may require further investigation. EXPERT OPINION Targeting specific Ca2+ signaling cascades could disrupt normal cellular activities, making cancer therapy complex and elusive. Therefore, there is a need for improvements in current Ca2+ signaling pathway focused medicines. While synthetic molecules and plant compounds show promise, they also come with certain limitations. Hence, exploring the framework of targeted drug delivery, structure-rationale-based designing, and repurposing potential drugs to target Ca2+ transporting proteins could potentially lead to a significant breakthrough in cancer treatment.
Collapse
Affiliation(s)
- Jyoti Singh
- Bioprospection and Product Development Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
- Jawaharlal Nehru University, New Delhi, India
| | - Abha Meena
- Bioprospection and Product Development Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Suaib Luqman
- Bioprospection and Product Development Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| |
Collapse
|
2
|
Ghrelin and Cancer: Examining the Roles of the Ghrelin Axis in Tumor Growth and Progression. Biomolecules 2022; 12:biom12040483. [PMID: 35454071 PMCID: PMC9032665 DOI: 10.3390/biom12040483] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 02/07/2023] Open
Abstract
Ghrelin, a hormone produced and secreted from the stomach, is prim arily known as an appetite stimulant. Recently, it has emerged as a potential regulator/biomarker of cancer progression. Inconsistent results on this subject make this body of literature difficult to interpret. Here, we attempt to identify commonalities in the relationships between ghrelin and various cancers, and summarize important considerations for future research. The main players in the ghrelin family axis are unacylated ghrelin (UAG), acylated ghrelin (AG), the enzyme ghrelin O-acyltransferase (GOAT), and the growth hormone secretagogue receptor (GHSR). GOAT is responsible for the acylation of ghrelin, after which ghrelin can bind to the functional ghrelin receptor GHSR-1a to initiate the activation cascade. Splice variants of ghrelin also exist, with the most prominent being In1-ghrelin. In this review, we focus primarily on the potential of In1-ghrelin as a biomarker for cancer progression, the unique characteristics of UAG and AG, the importance of the two known receptor variants GHSR-1a and 1b, as well as the possible mechanisms through which the ghrelin axis acts. Further understanding of the role of the ghrelin axis in tumor cell proliferation could lead to the development of novel therapeutic approaches for various cancers.
Collapse
|
3
|
Spiridon IA, Ciobanu DGA, Giușcă SE, Căruntu ID. Ghrelin and its role in gastrointestinal tract tumors (Review). Mol Med Rep 2021; 24:663. [PMID: 34296307 PMCID: PMC8335721 DOI: 10.3892/mmr.2021.12302] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 06/23/2021] [Indexed: 12/13/2022] Open
Abstract
Ghrelin, an orexigenic hormone, is a peptide that binds to the growth hormone secretagogue receptor; it is secreted mainly by enteroendocrine cells in the oxyntic glands of the stomach. Ghrelin serves a role in both local and systemic physiological processes, and is implicated in various pathologies, including neoplasia, with tissue expression in several types of malignancies in both in vitro and in vivo studies. However, the precise implications of the ghrelin axis in metastasis, invasion and cancer progression regulation has yet to be established. In the case of gastrointestinal (GI) tract malignancies, ghrelin has shown potential to become a prognostic factor or even a therapeutic target, although data in the literature are inconsistent and unsystematic, with reports untailored to a specific histological subtype of cancer or a particular localization. The evaluation of immunohistochemical expression shows a limited outlook owing to the low number of cases analyzed, and in vivo analyses have conflicting data regarding differences in ghrelin serum levels in patients with cancer. The aim of this review was to examine the relationship between ghrelin and GI tract malignancies to demonstrate the inconsistencies in current results and to highlight its clinical significance in the outcome of these patients.
Collapse
Affiliation(s)
- Irene Alexandra Spiridon
- Department of Pathology, 'Grigore T. Popa' University of Medicine and Pharmacy, Iași 700115, Romania
| | | | - Simona Eliza Giușcă
- Department of Pathology, 'Grigore T. Popa' University of Medicine and Pharmacy, Iași 700115, Romania
| | - Irina Draga Căruntu
- Department of Histology, 'Grigore T. Popa' University of Medicine and Pharmacy, Iași 700115, Romania
| |
Collapse
|
4
|
Ye H, Yang Y, Chen R, Shi X, Fang Y, Yang J, Dong Y, Chen L, Xia J, Wang C, Yang C, Feng J, Wang Y, Feng X, Lü C. Recognition of Invasive Prostate Cancer Using a GHRL Polypeptide Probe Targeting GHSR in a Mouse Model In Vivo. Curr Pharm Des 2020; 26:1614-1621. [PMID: 31880242 DOI: 10.2174/1381612826666191227160001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/23/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Ghrelin (GHRL) is a polypeptide that can specifically bind to the growth hormone secretagogue receptor (GHSR). The expression of GHSR is significantly different in normal and prostate cancer (PC) tissues in humans. It is important to find an effective diagnostic method for the diagnosis and prognosis of invasive PC/neuroendocrine prostate cancer (NEPC). METHODS GHRL and GHSR mRNA levels were determined by a quantitative real-time polymerase chain reaction in PC tissues. The expression of GHRL and GHSR proteins was assessed by Western blot assay and immunohistochemistry. A GHRL polypeptide probe was synthesized by standard solid-phase polypeptide synthesis, and labeled with Alexa Fluor 660. Confocal microscopy was used to capture fluorescence images. Living imaging analysis showed tumor areas of different invasiveness in mice models. RESULTS The levels of GHRL and GHSR copy number amplification and mRNA expression were increased in invasive PC/NEPC, and the protein expression levels of GHRL and GHSR were similarly increased in NEPC. The GHRL polypeptide probe could effectively bind to GHSR. In PC3 cells, it was found that the GHRL probe specifically binds to GHSR on the cell membrane and accumulates in the cells through internalization after binding. Live imaging in mice models showed that there were different signal intensities in tumor areas with different invasiveness. CONCLUSION GHSR and GHRL might be used in molecular imaging diagnosis for invasive PC/NEPC in the future.
Collapse
Affiliation(s)
- Huamao Ye
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Yue Yang
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Rui Chen
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Xiaolei Shi
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Yu Fang
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Jun Yang
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Yuanzhen Dong
- State Key Laboratory of Innovative Drugs and Pharmaceutical Technology, Shanghai Institute of Pharmaceutical Industry, Shanghai, China
| | - Lili Chen
- State Key Laboratory of Innovative Drugs and Pharmaceutical Technology, Shanghai Institute of Pharmaceutical Industry, Shanghai, China
| | - Jianghua Xia
- State Key Laboratory of Innovative Drugs and Pharmaceutical Technology, Shanghai Institute of Pharmaceutical Industry, Shanghai, China
| | - Chao Wang
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Chenghua Yang
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Jun Feng
- State Key Laboratory of Innovative Drugs and Pharmaceutical Technology, Shanghai Institute of Pharmaceutical Industry, Shanghai, China
| | - Yang Wang
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Xiang Feng
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China
| | - Chen Lü
- Department of Urology, Shanghai Changhai Hospital Affiliated to the Second Military Medical University, Shanghai, China.,Department of Urology, Shanghai East Hospital Affiliated to Shanghai Tongji University, Shanghai, China
| |
Collapse
|
5
|
Exogenous Ghrelin Increases Plasma Insulin Level in Diabetic Rats. Biomolecules 2020; 10:biom10040633. [PMID: 32325912 PMCID: PMC7226305 DOI: 10.3390/biom10040633] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/09/2020] [Accepted: 04/15/2020] [Indexed: 12/13/2022] Open
Abstract
Ghrelin, a 28-amino acid peptide, is a strong growth hormone secretagogue and a regulator of food intake. In addition, ghrelin is thought to play a role in insulin secretion and in glucose homeostasis. A lot of contradictory data have been reported in the literature regarding the co-localization of ghrelin with other hormones in the islet of Langerhans, its role in insulin secretion and attenuation of type 2 diabetes mellitus. In this study, we investigate the effect of chronic ghrelin treatment on glucose, body weight and insulin level in normal and streptozotocin-induced diabetic male Wistar rats. We have also examined the distribution pattern and co-localization of ghrelin with insulin in pancreatic islet cells using immunohistochemistry and immune-electron microscopy and the ability of ghrelin to stimulate insulin release from the CRL11065 beta cell line. Control, non-diabetic groups received intraperitoneal injection of normal saline, while treated groups received intraperitoneal injection of 5 µg/kg body weight of ghrelin (amino acid chain 24–51) on a daily basis for a duration of four weeks. Our results show that the administration of ghrelin increases the number of insulin-secreting beta cells and serum insulin level in both normal and diabetic rats. We also demonstrated that ghrelin co-localizes with insulin in pancreatic islet cells and that the pattern of ghrelin distribution is altered after the onset of diabetes. Moreover, ghrelin at a dose of 10−6 M and 10−12 M increased insulin release from the CRL11065 beta cell line. In summary, ghrelin co-localizes with insulin in the secretory granules of pancreatic beta cells and enhances insulin production.
Collapse
|
6
|
Maugham ML, Seim I, Thomas PB, Crisp GJ, Shah ET, Herington AC, Brown KA, Gregory LS, Nelson CC, Jeffery PL, Chopin LK. No effect of unacylated ghrelin administration on subcutaneous PC3 xenograft growth or metabolic parameters in a Rag1-/- mouse model of metabolic dysfunction. PLoS One 2018; 13:e0198495. [PMID: 30458004 PMCID: PMC6245673 DOI: 10.1371/journal.pone.0198495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 11/02/2018] [Indexed: 12/12/2022] Open
Abstract
Ghrelin is a peptide hormone which, when acylated, regulates appetite, energy balance and a range of other biological processes. Ghrelin predominately circulates in its unacylated form (unacylated ghrelin; UAG). UAG has a number of functions independent of acylated ghrelin, including modulation of metabolic parameters and cancer progression. UAG has also been postulated to antagonise some of the metabolic effects of acyl-ghrelin, including its effects on glucose and insulin regulation. In this study, Rag1-/- mice with high-fat diet-induced obesity and hyperinsulinaemia were subcutaneously implanted with PC3 prostate cancer xenografts to investigate the effect of UAG treatment on metabolic parameters and xenograft growth. Daily intraperitoneal injection of 100 μg/kg UAG had no effect on xenograft tumour growth in mice fed normal rodent chow or 23% high-fat diet. UAG significantly improved glucose tolerance in host Rag1-/- mice on a high-fat diet, but did not significantly improve other metabolic parameters. We propose that UAG is not likely to be an effective treatment for prostate cancer, with or without associated metabolic syndrome.
Collapse
Affiliation(s)
- Michelle L. Maugham
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Skeletal Biology and Forensic Anthropology Research Laboratory, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Inge Seim
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Integrative Biology Laboratory, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Patrick B. Thomas
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Gabrielle J. Crisp
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Esha T. Shah
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Adrian C. Herington
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Kristy A. Brown
- Department of Medicine, Weill Cornell Medicine, New York City, New York, United States of America
| | - Laura S. Gregory
- Skeletal Biology and Forensic Anthropology Research Laboratory, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Colleen C. Nelson
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Penny L. Jeffery
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Lisa K. Chopin
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| |
Collapse
|
7
|
Wang W, Chen ZX, Guo DY, Tao YX. Regulation of prostate cancer by hormone-responsive G protein-coupled receptors. Pharmacol Ther 2018; 191:135-147. [PMID: 29909235 DOI: 10.1016/j.pharmthera.2018.06.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 06/01/2018] [Indexed: 11/27/2022]
Abstract
Regulation of prostate cancer by androgen and androgen receptor (AR), and blockade of AR signaling by AR antagonists and steroidogenic enzyme inhibitors have been extensively studied. G protein-coupled receptors (GPCRs) are a family of membrane receptors that regulate almost all physiological processes. Nearly 40% of FDA-approved drugs in the market target GPCRs. A variety of GPCRs that mediate reproductive function have been demonstrated to be involved in the regulation of prostate cancer. These GPCRs include gonadotropin-releasing hormone receptor, luteinizing hormone receptor, follicle-stimulating hormone receptor, relaxin receptor, ghrelin receptor, and kisspeptin receptor. We highlight here GPCR regulation of prostate cancer by these GPCRs. Further therapeutic approaches targeting these GPCRs for the treatment of prostate cancer are summarized.
Collapse
Affiliation(s)
- Wei Wang
- Department of Clinical Laboratory, Xiamen Huli Guoyu Clinic, Co., Ltd., Xiamen, China
| | - Zhao-Xia Chen
- Department of Clinical Laboratory, Xiamen Huli Guoyu Clinic, Co., Ltd., Xiamen, China
| | - Dong-Yu Guo
- Department of Clinical Laboratory, Xiamen Huli Guoyu Clinic, Co., Ltd., Xiamen, China.
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, USA.
| |
Collapse
|
8
|
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.
Collapse
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.
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
O'Rourke RW. Obesity and cancer: at the crossroads of cellular metabolism and proliferation. Surg Obes Relat Dis 2014; 10:1208-19. [PMID: 25264328 PMCID: PMC4267907 DOI: 10.1016/j.soard.2014.08.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 08/19/2014] [Accepted: 08/21/2014] [Indexed: 12/14/2022]
Abstract
Obesity is associated with an increased risk of cancer. The mechanisms underlying this association include but are not limited to increased systemic inflammation, an anabolic hormonal milieu, and adipocyte-cancer crosstalk, aberrant stimuli that conspire to promote neoplastic transformation. Cellular proliferation is uncoupled from nutrient availability in malignant cells, promoting tumor progression. Elucidation of the mechanisms underlying the obesity-cancer connection will lead to the development of novel metabolism-based agents for cancer prevention and treatment.
Collapse
Affiliation(s)
- Robert W O'Rourke
- Department of Surgery, University of Michigan and Ann Arbor VA Hospital, Ann Arbor, Michigan.
| |
Collapse
|
11
|
Callaghan B, Furness JB. Novel and Conventional Receptors for Ghrelin, Desacyl-Ghrelin, and Pharmacologically Related Compounds. Pharmacol Rev 2014; 66:984-1001. [DOI: 10.1124/pr.113.008433] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
|
12
|
Antiproliferative activity on human prostate carcinoma cell lines of new peptidomimetics containing the spiroazepinoindolinone scaffold. Bioorg Med Chem 2013; 21:5470-9. [DOI: 10.1016/j.bmc.2013.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 05/30/2013] [Accepted: 06/04/2013] [Indexed: 11/19/2022]
|
13
|
Lawnicka H, Mełeń-Mucha G, Motylewska E, Mucha S, Stępień H. Modulation of ghrelin axis influences the growth of colonic and prostatic cancer cells in vitro. Pharmacol Rep 2013; 64:951-9. [PMID: 23087147 DOI: 10.1016/s1734-1140(12)70890-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 03/08/2012] [Indexed: 01/03/2023]
Abstract
BACKGROUND The risk of different cancers seems to be associated with obesity. Moreover, low ghrelin levels observed in obese people may be implicated in cancer development and progression. The aim of this study was to examine the direct effects of both forms of ghrelin (acylated and unacylated) and ghrelin receptor type 1a antagonist (D-Lys-GHRP-6) on the growth of murine colon cancer MC38 and human prostate cancer DU145 cell lines in vitro. METHODS The cells were cultured for 72 h in the presence of rat or human acylated ghrelin (rG, hG), human unacylated ghrelin (hUAG), D-Lys-GHRP-6 (GHS-RA) applied either alone or jointly. The cell line growth was assessed by the colorimetric Mosmann method. RESULTS hUAG (10(-6), 10(-7) and 10(-10) M) inhibited MC38 cancer cell growth and, at some concentrations (10(-8), 10(-9), 10(-10) M), enhanced the antineoplastic effect of GHS-RA(10(-4) M). In turn, GHS-RA evoked a biphasic effect on MC38 cancer growth: inhibitory at 10(-4) M and stimulatory at 10(-5) and 10(-6) M. Moreover, GHS-RA at the highest examined concentration (10(-4) M) enhanced the cytostatic effect of FU. Human acylated and unacylated ghrelin and GHS-RA inhibited DU145 cancer growth with moderate and different potencies. A dose-response effect was observed for the inhibitory action of hG together with the synergistic effect of hUAG and GHS-RA. CONCLUSION The obtained results indicate an involvement of the ghrelin axis in the growth regulation of colon and prostate cancers and may suggest new therapeutic options for these neoplasms.
Collapse
Affiliation(s)
- Hanna Lawnicka
- Department of Immunoendocrinology, Medical University of Lodz, Łódź, Poland
| | | | | | | | | |
Collapse
|
14
|
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.
Collapse
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)
| |
Collapse
|
15
|
Chopin L, Walpole C, Seim I, Cunningham P, Murray R, Whiteside E, Josh P, Herington A. Ghrelin and cancer. Mol Cell Endocrinol 2011; 340:65-9. [PMID: 21616120 DOI: 10.1016/j.mce.2011.04.013] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 04/18/2011] [Accepted: 04/21/2011] [Indexed: 01/30/2023]
Abstract
Ghrelin is a peptide hormone that was originally isolated from the stomach as the endogenous ligand for the growth hormone secretagogue receptor (GHSR). Ghrelin has many functions, including the regulation of appetite and gut motility, growth hormone release from the anterior pituitary and roles in the cardiovascular and immune systems. Ghrelin and its receptor are expressed in a number of cancers and cancer cell lines and may play a role in processes associated with cancer progression, including cell proliferation, apoptosis, and cell invasion and migration.
Collapse
Affiliation(s)
- Lisa Chopin
- Queensland University of Technology, Brisbane, Australia.
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Shishkin SS, Lisitskaya KV, Krakhmaleva IN. Biochemical polymorphism of the growth hormone system proteins and its manifestations in human prostate cells. BIOCHEMISTRY (MOSCOW) 2011; 75:1547-62. [PMID: 21417994 DOI: 10.1134/s0006297910130043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The basic mechanisms are considered that are responsible for producing biochemical polymorphism of human proteins realized at three basic levels: the structures of genome and genes; the transcription and maturation of transcripts; the postsynthetic formation of functionally active protein products of gene expression. The data on biochemical polymorphism of growth hormone (GH) and some other proteins that are directly or indirectly necessary for its functioning and support this polymorphism by polylocus, polyallelism, alternative splicing, and various postsynthetic modifications are analyzed. The role of polymorphic proteins of the GH system is discussed in formation of a variety of oligomeric molecular structures of this system (multicomponent transport complexes, receptors, and endocellular protein ensembles involved in the regulation of gene expression). It is emphasized that such structural polymorphism significantly influences the biological effects in various parts of the GH system during physiological processes and in tumors, in particular in prostate cancer.
Collapse
Affiliation(s)
- S S Shishkin
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia.
| | | | | |
Collapse
|
17
|
Ashrafian H, Ahmed K, Rowland SP, Patel VM, Gooderham NJ, Holmes E, Darzi A, Athanasiou T. Metabolic surgery and cancer: protective effects of bariatric procedures. Cancer 2010; 117:1788-99. [PMID: 21509756 DOI: 10.1002/cncr.25738] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2010] [Revised: 09/08/2010] [Accepted: 09/27/2010] [Indexed: 01/09/2023]
Abstract
The worldwide epidemic of obesity and the global incidence of cancer are both increasing. There is now epidemiological evidence to support a correlation between obesity, weight gain, and some cancers. Metabolic or bariatric surgery can provide sustained weight loss and reduced obesity-related mortality. These procedures can also improve the metabolic profile to decrease cardiovascular risk and resolve diabetes in morbidly obese patients. The operations offer several physiological steps, the so-called BRAVE effects: 1) bile flow alteration, 2) reduction of gastric size, 3) anatomical gut rearrangement and altered flow of nutrients, 4) vagal manipulation and 5) enteric gut hormone modulation. Metabolic operations are also associated with a significant reduction of cancer incidence and mortality. The cancer-protective role of metabolic surgery is strongest for female obesity-related tumors; however, the underlying mechanisms may involve both weight-dependent and weight-independent effects. These include the improvement of insulin resistance with attenuation of the metabolic syndrome as well as decreased oxidative stress and inflammation in addition to the beneficial modulation of sex steroids, gut hormones, cellular energetics, immune system, and adipokines. Elucidating the precise metabolic mechanisms of cancer prevention by metabolic surgery can increase our understanding of how obesity, diabetes, and metabolic syndrome are associated with cancer. It may also offer novel treatment strategies in the management of tumor generation and growth.
Collapse
Affiliation(s)
- Hutan Ashrafian
- Department of Surgery and Cancer, Imperial College London, London, England.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Dong XY, Xu J, Tang SQ, Li HY, Jiang QY, Zou XT. Ghrelin and its biological effects on pigs. Peptides 2009; 30:1203-11. [PMID: 19463757 DOI: 10.1016/j.peptides.2009.03.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 03/01/2009] [Accepted: 03/02/2009] [Indexed: 12/23/2022]
Abstract
Ghrelin is a 28 amino acid peptide, which produces its marked effects through binding to the endogenous ligand of the growth hormone secretagogue receptor (GHS-R). Based on the contemporary literatures, it was shown that ghrelin was involved in a series of biological functions including regulation of food intake, body weight, gastrointestinal (GI) motility, hormone secretion, glucose release, cardiovascular functions, enzyme release, cell proliferation and reproduction in pigs through binding to GHS-R 1a or unidentified receptors. It was also observed that ghrelin induced adipocyte and hepatocyte proliferation of primary cultured piglet. In this paper, recent research on ghrelin structure, distribution, GHS-R receptor, biological functions and its regulatory mechanisms for pigs are presented.
Collapse
Affiliation(s)
- Xiao-Ying Dong
- College of Yingdong Bioengineering, Shaoguan University, Zhenjiang District, Shaoguan, Guangdong, China
| | | | | | | | | | | |
Collapse
|
19
|
Abstract
Many of the most common cancers that blight our societies are very rare in other large populations in the world; studies of migrants exclude a simple genetic explanation for these wide geographical variations and imply that environmental exposures are key determinants of the development of these cancers. The most heavily implicated factor is nutrition. There are many other clinical indicators that nutrition, energy balance and metabolic status are perturbed in large numbers of individuals in 'Westernized' societies. Many of the tissue morbidities associated with metabolic disturbance are mediated by the consequent hormonal perturbations, and it is likely that these endocrine controls also mediate the effects of nutrition and metabolic status on the development of many clinical cancers. The recent characterization of the genomic landscape of breast and colorectal cancers have established that a few cell signalling pathways are critical for the clinical course of these cancers, in particular cell signalling pathways that are also central to the regulation of cell metabolism. These signalling pathways are normally under hormonal control, and again this evidence suggests that these hormonal controls may determine the context that is permissive for the progression of clinical cancers. This new understanding indicates that many cancers are potentially preventable, and that nutrition, metabolic and endocrine interventions are the most promising strategies for disease prevention.
Collapse
Affiliation(s)
- Jeff M P Holly
- Department of Clinical Science at North Bristol, University of Bristol, Paul O'Gorman Lifeline Centre, Southmead Hospital, Bristol BS10 5NB, UK.
| | | |
Collapse
|
20
|
Abstract
PURPOSE OF REVIEW The purpose of this review is to summarize recent studies that investigated the role of ghrelin and ghrelin analogs in wasting conditions. RECENT FINDINGS Numerous studies have demonstrated potential beneficial effects exerted by ghrelin in a number of diseases associated with wasting. Besides ghrelin's orexigenic effect, anabolic as well as anti-inflammatory activity mediated by ghrelin have been investigated in wasting conditions such as cancer, diabetes mellitus, malabsorptive diseases, chronic obstructive pulmonary disease, anorexia nervosa, renal failure, liver failure, and chronic heart failure. Encouraging results have been obtained from experimental studies and a few clinical trials using subcutaneous administration of ghrelin and ghrelin agonists in cachexia. In-vitro studies have shown ghrelin and des-acyl ghrelin biological activities on proliferation of tumor cells and abnormal tissues. SUMMARY The recent studies support the possible positive effects of ghrelin in therapeutic approaches and adjunct treatment of a number of diseases associated with wasting. Utilization of agonists of the ghrelin receptor growth hormone secretagogue-1a is a promising approach for clinical use. Randomized and placebo-controlled studies, including large number of patients are further required.
Collapse
Affiliation(s)
- Mayra M Kamiji
- Department of Gastroenterology, Faculty of Medicine, University of São Paulo, Ribeirão Preto, Brazil
| | | |
Collapse
|