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Halmos G, Szabo Z, Juhasz E, Schally AV. Signaling mechanism of growth hormone-releasing hormone receptor. VITAMINS AND HORMONES 2023; 123:1-26. [PMID: 37717982 DOI: 10.1016/bs.vh.2023.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
The hypothalamic peptide growth hormone-releasing hormone (GHRH) stimulates the secretion of growth hormone (GH) from the pituitary through binding and activation of the pituitary type of GHRH receptor (GHRH-R), which belongs to the family of G protein-coupled receptors with seven potential membrane-spanning domains. Splice variants of GHRH-Rs (SV) in human tumors and other extra pituitary tissues were identified and their cDNA was sequenced. Among the SVs, splice variant 1 (SV1) possesses the greatest similarity to the full-length GHRH-R and remains functional by eliciting cAMP signaling and mitogenic activity upon GHRH stimulation. A large body of work have evaluated potential clinical applications of agonists and antagonists of GHRH in diverse fields, including endocrinology, oncology, cardiology, diabetes, obesity, metabolic dysfunctions, Alzheimer's disease, ophthalmology, wound healing and other applications. In this chapter, we briefly review the expression and potential function of GHRH-Rs and their SVs in various tissues and also elucidate and summarize the activation, molecular mechanism and signalization pathways of these receptors. Therapeutic applications of GHRH analogs are also discussed.
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Affiliation(s)
- Gabor Halmos
- Department of Biopharmacy, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary; Veterans Affairs Medical Center, Endocrine, Polypeptide and Cancer Institute, Miami, FL, United States.
| | - Zsuzsanna Szabo
- Department of Biopharmacy, Faculty of Pharmacy, University of Debrecen, Debrecen, Hungary
| | - Eva Juhasz
- Department of Pediatrics, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Andrew V Schally
- Veterans Affairs Medical Center, Endocrine, Polypeptide and Cancer Institute, Miami, FL, United States; Department of Pathology, Miller School of Medicine, University of Miami, Miami, FL, United States; Department of Medicine, Divisions of Hematology-Oncology and Endocrinology, Miller School of Medicine, University of Miami, Miami, FL, United States; Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, United States
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Szabo Z, Juhasz E, Schally AV, Dezso B, Huga S, Hernadi Z, Halmos G, Kiss C. Expression of Growth Hormone-Releasing Hormone and Its Receptor Splice Variants in Primary Human Endometrial Carcinomas: Novel Therapeutic Approaches. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27092671. [PMID: 35566020 PMCID: PMC9101386 DOI: 10.3390/molecules27092671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/11/2022] [Accepted: 04/14/2022] [Indexed: 11/16/2022]
Abstract
Antagonists of growth hormone-releasing hormone (GHRH) inhibit the growth of various tumors, including endometrial carcinomas (EC). However, tumoral receptors that mediate the antiproliferative effects of GHRH antagonists in human ECs have not been fully characterized. In this study, we investigated the expression of mRNA for GHRH and splice variants (SVs) of GHRH receptors (GHRH-R) in 39 human ECs and in 7 normal endometrial tissue samples using RT-PCR. Primers designed for the PCR amplification of mRNA for the full length GHRH-R and SVs were utilized. The PCR products were sequenced, and their specificity was confirmed. Nine ECs cancers (23%) expressed mRNA for SV1, three (7.7%) showed SV2 and eight (20.5%) revealed mRNA for SV4. The presence of SVs for GHRH-Rs could not be detected in any of the normal endometrial tissue specimens. The presence of specific, high affinity GHRH-Rs was also demonstrated in EC specimens using radioligand binding studies. Twenty-four of the investigated thirty-nine tumor samples (61.5%) and three of the seven corresponding normal endometrial tissues (42.9%) expressed mRNA for GHRH ligand. Our findings suggest the possible existence of an autocrine loop in EC based on GHRH and its tumoral SV receptors. The antiproliferative effects of GHRH antagonists on EC are likely to be exerted in part by the local SVs and GHRH system.
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Affiliation(s)
- Zsuzsanna Szabo
- Department of Biopharmacy, Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary; (Z.S.); (G.H.)
| | - Eva Juhasz
- Department of Pediatrics, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary;
| | - Andrew V. Schally
- Veterans Affairs Medical Center, Endocrine, Polypeptide and Cancer Institute, Miami, FL 33125, USA;
- Department of Pathology, Department of Medicine, Divisions of Hematology-Oncology and Endocrinology, Miller School of Medicine, University of Miami, Miami, FL 33101, USA
- Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL 33136, USA
| | - Balazs Dezso
- Department of Pathology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary;
| | - Sandor Huga
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (S.H.); (Z.H.)
| | - Zoltan Hernadi
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (S.H.); (Z.H.)
| | - Gabor Halmos
- Department of Biopharmacy, Faculty of Pharmacy, University of Debrecen, 4032 Debrecen, Hungary; (Z.S.); (G.H.)
- Veterans Affairs Medical Center, Endocrine, Polypeptide and Cancer Institute, Miami, FL 33125, USA;
| | - Csongor Kiss
- Department of Pediatrics, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary;
- Correspondence: ; Tel.: +36-52-452-747; Fax: +36-52-255-893
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Clancy H, Pruski M, Lang B, Ching J, McCaig CD. Glioblastoma cell migration is directed by electrical signals. Exp Cell Res 2021; 406:112736. [PMID: 34273404 DOI: 10.1016/j.yexcr.2021.112736] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 07/03/2021] [Accepted: 07/07/2021] [Indexed: 11/17/2022]
Abstract
Electric field (EF) directed cell migration (electrotaxis) is known to occur in glioblastoma multiforme (GBM) and neural stem cells, with key signalling pathways frequently dysregulated in GBM. One such pathway is EGFR/PI3K/Akt, which is down-regulated by peroxisome proliferator activated receptor gamma (PPARγ) agonists. We investigated the effect of electric fields on primary differentiated and glioma stem cell (GSCs) migration, finding opposing preferences for anodal and cathodal migration, respectively. We next sought to determine whether chemically disrupting Akt through PTEN upregulation with the PPARγ agonist, pioglitazone, would modulate electrotaxis of these cells. We found that directed cell migration was significantly inhibited with the addition of pioglitazone in both differentiated GBM and GSCs subtypes. Western blot analysis did not demonstrate any change in PPARγ expression with and without exposure to EF. In summary we demonstrate opposing EF responses in primary GBM differentiated cells and GSCs can be inhibited chemically by pioglitazone, implicating GBM EF modulation as a potential target in preventing tumour recurrence.
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Affiliation(s)
- Hannah Clancy
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Michal Pruski
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom; School of Medicine, Tongji University, Shanghai, China
| | - Bing Lang
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Jared Ching
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom; John Van Geest Centre for Brain Repair, University of Cambridge, Cambridge, United Kingdom.
| | - Colin D McCaig
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom.
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Marital status is associated with survival of patients with astrocytoma. J Clin Neurosci 2018; 56:79-87. [DOI: 10.1016/j.jocn.2018.07.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 06/10/2018] [Accepted: 07/08/2018] [Indexed: 12/23/2022]
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Xie JC, Yang S, Liu XY, Zhao YX. Effect of marital status on survival in glioblastoma multiforme by demographics, education, economic factors, and insurance status. Cancer Med 2018; 7:3722-3742. [PMID: 30009575 PMCID: PMC6089174 DOI: 10.1002/cam4.1688] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/20/2018] [Accepted: 06/18/2018] [Indexed: 12/17/2022] Open
Abstract
The relationship between marital status and glioblastoma multiforme (GBM) has not been addressed in depth. Here, we aimed to investigate the association between marital status and survival in GBM. We searched the Surveillance, Epidemiology, and End Results (SEER) database and extracted the data of eligible patients diagnosed with GBM after 2004. Marital status was classified as married, divorced/separated, widowed, and single. A Kaplan-Meier test was conducted to compare the survival curves of different groups. Multivariate Cox regression was performed to evaluate overall survival (OS) and cause-specific survival (CSS) in different groups. Subgroup analysis was applied according to demographics, typical education and income levels in the locale, and insurance status. A total of 30 767 eligible patients were included. The median OS values were 9, 7, 3, 9 months in married, divorced/separated, widowed, and single patients, respectively. After adjustment for other covariates, married patients had better OS and CSS than other patients had. In addition to marital status, demographic factors, disease progression factors, local educational level, and insurance status were also associated with survival in GBM. Furthermore, subgroup analyses revealed the protective effect of marriage in most of the comparisons. Notably, the protective effect of marriage becomes more and more apparent as time goes on. The advantageous effect of marriage on GBM survival is especially prominent in patients who are male, older than 60 years of age, White, or living in middle-income counties. In conclusion, marital status is an independent prognostic factor for GBM.
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Affiliation(s)
- Jun-Chao Xie
- Department of Neurology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shuai Yang
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xue-Yuan Liu
- Department of Neurology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yan-Xin Zhao
- Department of Neurology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
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RNA processing as an alternative route to attack glioblastoma. Hum Genet 2017; 136:1129-1141. [PMID: 28608251 DOI: 10.1007/s00439-017-1819-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 06/02/2017] [Indexed: 02/07/2023]
Abstract
Genomic analyses have become an important tool to identify new avenues for therapy. This is especially true for cancer types with extremely poor outcomes, since our lack of effective therapies offers no tangible clinical starting point to build upon. The highly malignant brain tumor glioblastoma (GBM) exemplifies such a refractory cancer, with only 15 month average patient survival. Analyses of several hundred GBM samples compiled by the TCGA (The Cancer Genome Atlas) have produced an extensive transcriptomic map, identified prevalent chromosomal alterations, and defined important driver mutations. Unfortunately, clinical trials based on these results have not yet delivered an improvement on outcome. It is, therefore, necessary to characterize other regulatory routes known for playing a role in tumor relapse and response to treatment. Alternative splicing affects more than 90% of the human coding genes and it is an important source for transcript variation and gene regulation. Mutations and alterations in splicing factors are highly prevalent in multiple cancers, demonstrating the potential for splicing to act as a tumor driver. As a result, numerous genes are expressed as cancer-specific splicing isoforms that are functionally distinct from the canonical isoforms found in normal tissue. These include genes that regulate cancer-critical pathways such as apoptosis, DNA repair, cell proliferation, and migration. Splicing defects can even induce genomic instability, a common characteristic of cancer, and a driver of tumor evolution. Importantly, components of the splicing machinery are targetable; multiple drugs can inhibit splicing factors or promote changes in splicing which could be exploited to begin improving clinical outcomes. Here, we review the current literature and present a case for exploring RNA processing as therapeutic route for the treatment of GBM.
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