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Sosa LDV, Picech F, Perez P, Gutierrez S, Leal RB, De Paul A, Torres A, Petiti JP. Regulation of FGF2-induced proliferation by inhibitory GPCR in normal pituitary cells. Front Endocrinol (Lausanne) 2023; 14:1183151. [PMID: 37576961 PMCID: PMC10414184 DOI: 10.3389/fendo.2023.1183151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 07/13/2023] [Indexed: 08/15/2023] Open
Abstract
Introduction Intracellular communication is essential for the maintenance of the anterior pituitary gland plasticity. The aim of this study was to evaluate whether GPCR-Gαi modulates basic fibroblast growth factor (FGF2)-induced proliferative activity in normal pituitary cell populations. Methods Anterior pituitary primary cell cultures from Wistar female rats were treated with FGF2 (10ng/mL) or somatostatin analog (SSTa, 100nM) alone or co-incubated with or without the inhibitors of GPCR-Gαi, pertussis toxin (PTX, 500nM), MEK inhibitor (U0126, 100µM) or PI3K inhibitor (LY 294002, 10 μM). Results FGF2 increased and SSTa decreased the lactotroph and somatotroph BrdU uptak2e (p<0.05) whereas the FGF2-induced S-phase entry was prevented by SSTa co-incubation in both cell types, with these effects being reverted by PTX, U0126 or LY294002 pre-incubation. The inhibition of lactotroph and somatotroph mitosis was associated with a downregulation of c-Jun expression, a decrease of phosphorylated (p) ERK and pAKT. Furthermore, SSTa was observed to inhibit the S-phase entry induced by FGF2, resulting in a further increase in the number of cells in the G1 phase and a concomitant reduction in the number of cells in the S phases (p< 0.05), effects related to a decrease of cyclin D1 expression and an increase in the expression of the cell cycle inhibitors p27 and p21. Discussion In summary, the GPCR-Gαi activated by SSTa blocked the pro-proliferative effect of FGF2 in normal pituitary cells via a MEK-dependent mechanism, which acts as a mediator of both anti and pro-mitogenic signals, that may regulate the principal effectors of the G1 to S-phase transition.
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Affiliation(s)
- Liliana del V. Sosa
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
| | - Florencia Picech
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
| | - Pablo Perez
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
| | - Silvina Gutierrez
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
| | - Rodrigo Bainy Leal
- Universidade Federal de Santa Catarina, Florianópolis, Departamento de Bioquímica e Programa de Pós-graduação em Bioquímica, Centro de Ciências Biológicas, Santa Catarina, Brazil
| | - Ana De Paul
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
| | - Alicia Torres
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
| | - Juan Pablo Petiti
- Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas Técnicas (CONICET), Instituto de Investigaciones en Ciencias de la Salud (INICSA), Córdoba, Argentina
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Marques P, Silva AL, López-Presa D, Faria C, Bugalho MJ. The microenvironment of pituitary adenomas: biological, clinical and therapeutical implications. Pituitary 2022; 25:363-382. [PMID: 35194709 DOI: 10.1007/s11102-022-01211-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/15/2022] [Indexed: 10/19/2022]
Abstract
The microenvironment of pituitary adenomas (PAs) includes a range of non-tumoral cells, such as immune and stromal cells, as well as cell signaling molecules such as cytokines, chemokines and growth factors, which surround pituitary tumor cells and may modulate tumor initiation, progression, invasion, angiogenesis and other tumorigenic processes. The microenvironment of PAs has been actively investigated over the last years, with several immune and stromal cell populations, as well as different cytokines, chemokines and growth factors being recently characterized in PAs. Moreover, key microenvironment-related genes as well as immune-related molecules and pathways have been investigated, with immune check point regulators emerging as promising targets for immunotherapy. Understanding the microenvironment of PAs will contribute to a deeper knowledge of the complex biology of PAs, as well as will provide developments in terms of diagnosis, clinical management and ultimately treatment of patients with aggressive and/or refractory PAs.
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Affiliation(s)
- Pedro Marques
- Endocrinology Department, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte (CHULN), Lisbon, Portugal.
| | - Ana Luísa Silva
- Endocrinology Department, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte (CHULN), Lisbon, Portugal
- Faculty of Medicine, Lisbon University, Lisbon, Portugal
| | - Dolores López-Presa
- Pathology Department, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte (CHULN), Lisbon, Portugal
| | - Cláudia Faria
- Neurosurgery Department, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte (CHULN), Lisbon, Portugal
| | - Maria João Bugalho
- Endocrinology Department, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte (CHULN), Lisbon, Portugal
- Faculty of Medicine, Lisbon University, Lisbon, Portugal
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Marques P, Barry S, Carlsen E, Collier D, Ronaldson A, Grieve J, Dorward N, Mendoza N, Nair R, Muquit S, Grossman AB, Korbonits M. The expression of neural cell adhesion molecule and the microenvironment of pituitary neuroendocrine tumours. J Neuroendocrinol 2021; 33:e13052. [PMID: 34708902 DOI: 10.1111/jne.13052] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/09/2021] [Accepted: 10/06/2021] [Indexed: 12/19/2022]
Abstract
The neural cell adhesion molecule (NCAM) has previously been studied in pituitary neuroendocrine tumours (PitNETs), but its role in tumour biology and aggressiveness remains controversial, and its relationship with the tumour microenvironment remains unknown. We aimed to characterise NCAM expression in PitNETs, to correlate this with clinico-pathological features, and to assess the role of various microenvironment components on NCAM expression. NCAM and immune cells were investigated by immunohistochemistry in 16 human non-functioning-PitNETs (NF-PitNETs) and eight somatotrophinomas, including macrophages (CD68, CD163, HLA-DR), cytotoxic (CD8) and T helper (CD4) lymphocytes, regulatory T cells (FOXP3), B cells (CD20), and neutrophils (neutrophil elastase). Five normal pituitaries were included for comparison. The cytokine secretome from these PitNETs and from PitNET-derived tumour-associated fibroblasts (TAFs) were assessed on culture supernatants using a multiplex immunoassay panel. There were no significant NCAM expression differences between PitNETs and normal pituitary, and no difference between types of pituitary tumours (NF-PitNETs vs. somatotrophinomas). There was no association between NCAM expression and different clinico-pathological features, including cavernous sinus invasion and Ki-67, nor with serum hormone levels. NCAM immunoreactivity correlated negatively with PitNET-derived CXCL10 (rho = -0.417; p = .042) and CX3CL1 (rho = -0.423; p = .040) levels. NCAM immunoreactivity was negatively correlated with TAF-derived fibroblast growth factor (FGF)-2 (rho = -0.632; p = .009), but not with other TAF-derived cytokines. Within the PitNET cohort, there were no correlations between NCAM immunoreactivity and immune infiltrates or ratios, although, within NF-PitNETs, NCAM expression was higher in tumours with more FOXP3+ cells. NCAM expression does not differ between PitNETs and normal pituitary, and does not appear to relate to tumour invasiveness or proliferation. However, our data suggest a possible role for cytokines in the modulation of NCAM expression in PitNETs, particularly CXCL10, CX3CL1 and FGF-2, but not for immune cell infiltrates.
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Affiliation(s)
- Pedro Marques
- Centre for Endocrinology, Barts and the London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, UK
- Department of Endocrinology, Hospital de Santa Maria, Centro Hospitalar Universitário Lisboa Norte, Lisbon, Portugal
| | - Sayka Barry
- Centre for Endocrinology, Barts and the London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, UK
| | | | - David Collier
- Centre for Endocrinology, Barts and the London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Amy Ronaldson
- Centre for Endocrinology, Barts and the London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Joan Grieve
- The National Hospital for Neurology and Neurosurgery, UCLH, NHS Trust, London, UK
| | - Neil Dorward
- The National Hospital for Neurology and Neurosurgery, UCLH, NHS Trust, London, UK
| | - Nigel Mendoza
- Department of Neurosurgery, Charing Cross Hospital, Imperial College, London, UK
| | - Ramesh Nair
- Department of Neurosurgery, Charing Cross Hospital, Imperial College, London, UK
| | - Samiul Muquit
- Department of Neurosurgery, Derriford Hospital, Plymouth, UK
| | - Ashley B Grossman
- Centre for Endocrinology, Barts and the London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Márta Korbonits
- Centre for Endocrinology, Barts and the London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, UK
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Durcan E, Keskin FE, Ozkaya HM, Sirolu S, Sahin S, Korkmaz OP, Gazioglu N, Tanriover N, Comunoglu N, Oz B, Kizilkilic O, Kadioglu P. Fibroblast Growth Factor Receptor-4 Expression in Pituitary Adenomas is Associated with Aggressive Tumor Features. Exp Clin Endocrinol Diabetes 2021; 130:125-133. [PMID: 34255320 DOI: 10.1055/a-1523-7216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE To investigate the relationship of Fibroblast Growth Factor Receptor-4 (FGFR-4) expression with radiologic, pathologic, and clinical parameters in pituitary adenomas. METHODS Among 307 patients who underwent pituitary surgery for a pituitary adenoma between 2000 and 2015, we included 161 patients (53 gonadotroph, 26 corticotroph, 25 null cell, 22 lactotroph, 13 somatotroph, 8 adenomas with unusual combination, 7 Pit-1 positive adenomas, and 7 lactosomatotroph) based on availability of pathology specimens. Patients' radiologic, pathologic, and clinical parameters were determined. FGFR-4 immunostaining was evaluated using a semi-quantitative histologic score (H-score). RESULTS The mean follow-up period was 61 (IQR=32-84) months. The median H-scores for FGFR-4 were higher in patients without remission, those with residual lesion, and T2-hyperintense adenoma (p<0.05). Ki-67 level was higher in patients without remission compared to those in remission (p<0.05). The mean Ki-67 levels did not differ between patients with and without residual lesion or T2-hyperintense tumor (p>0.05). There was no significant difference (p>0.05) when the H-score and Ki-67 levels were assessed in terms of sex, sellar-dural invasion, Knosp and a grading system for superior, inferior, parasellar, anterior and posterior tumor extension Classification, tumor function or presence of poor subtype. Adenomas with Ki-67 expression ≥3% had higher FGFR4 expression levels than those with <3% expression (p=0.002). There was a weak positive correlation between H-score and Ki-67 (p=0.011; r=0.201). CONCLUSIONS Higher levels of FGFR-4 in pituitary adenomas could be use a marker for more aggressive tumor behavior.
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Affiliation(s)
- Emre Durcan
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Fatma Ela Keskin
- Division of Endocrinology and Metabolism, Department of Internal Medicine, T.C. Demiroglu Bilim University, Istanbul, Turkey
| | - Hande Mefkure Ozkaya
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Sabri Sirolu
- Department of Radiodiagnostic, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Serdar Sahin
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Ozge Polat Korkmaz
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Nurperi Gazioglu
- Department of Neurosurgery, T.C. Demiroglu Bilim University, Istanbul, Turkey
| | - Necmettin Tanriover
- Department of Neurosurgery, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Nil Comunoglu
- Department of Pathology, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Buge Oz
- Department of Pathology, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Osman Kizilkilic
- Department of Radiodiagnostic, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Pinar Kadioglu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Cerrahpasa Medical School, Istanbul University-Cerrahpasa, Istanbul, Turkey
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Marques P, Grossman AB, Korbonits M. The tumour microenvironment of pituitary neuroendocrine tumours. Front Neuroendocrinol 2020; 58:100852. [PMID: 32553750 DOI: 10.1016/j.yfrne.2020.100852] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 05/26/2020] [Accepted: 06/02/2020] [Indexed: 02/06/2023]
Abstract
The tumour microenvironment (TME) includes a variety of non-neoplastic cells and non-cellular elements such as cytokines, growth factors and enzymes surrounding tumour cells. The TME emerged as a key modulator of tumour initiation, progression and invasion, with extensive data available in many cancers, but little is known in pituitary tumours. However, the understanding of the TME of pituitary tumours has advanced thanks to active research in this field over the last decade. Different immune and stromal cell subpopulations, and several cytokines, growth factors and matrix remodelling enzymes, have been characterised in pituitary tumours. Studying the TME in pituitary tumours may lead to a better understanding of tumourigenic mechanisms, identification of biomarkers useful to predict aggressive disease, and development of novel therapies. This review summarises the current knowledge on the different TME cellular/non-cellular elements in pituitary tumours and provides an overview of their role in tumourigenesis, biological behaviour and clinical outcomes.
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Affiliation(s)
- Pedro Marques
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
| | - Ashley B Grossman
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
| | - Márta Korbonits
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
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Shen Z, Asa SL, Ezzat S. Ikaros and its interacting partner CtBP target the metalloprotease ADAMTS10 to modulate pituitary cell function. Mol Cell Endocrinol 2017; 439:126-132. [PMID: 27815209 DOI: 10.1016/j.mce.2016.10.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 10/28/2016] [Accepted: 10/29/2016] [Indexed: 12/23/2022]
Abstract
We have previously described the expression and up-regulation of the C-terminal Binding Protein (CtBP) in response to pituitary hypoxia. This co-repressor interacts with the hematopoietic factor Ikaros to target several components implicated in cellular growth and apoptotic pathways. To identify common transcriptional pituitary targets we performed promoter arrays using Ikaros and CtBP chromatin immunoprecipitated (ChIP) DNA from pituitary AtT20 cells. This approach yielded a finite list of gene targets common to both transcription factors. Of these, the metalloprotease ADAMTS10 emerged as a validated target. We show the ability of Ikaros to bind the ADAMTS10 promoter, influence its transfected activity, and induce endogenous gene expression. ADAMTS10 is expressed in primary pituitary cells and is down-regulated in Ikaros null mice. Further, knockdown of ADAMTS10 in AtT20 cells recapitulates the impact of Ikaros deficiency on POMC/ACTH hormone expression. These results uncover a novel role for the metalloprotease ADAMTS10 in the pituitary. Additionally, they position this metalloprotease as a potential functional integrator of the Ikaros-CtBP chromatin remodeling network.
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Affiliation(s)
- Zhongyi Shen
- Dept. of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario M5G 2M9, Canada; University Health Network and the Ontario Cancer Institute, Toronto, Ontario M5G 2M9, Canada
| | - Sylvia L Asa
- Dept. of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario M5G 2M9, Canada; University Health Network and the Ontario Cancer Institute, Toronto, Ontario M5G 2M9, Canada
| | - Shereen Ezzat
- Dept. of Medicine, University of Toronto, Toronto, Ontario M5G 2M9, Canada; University Health Network and the Ontario Cancer Institute, Toronto, Ontario M5G 2M9, Canada.
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Zubeldia-Brenner L, Roselli CE, Recabarren SE, Gonzalez Deniselle MC, Lara HE. Developmental and Functional Effects of Steroid Hormones on the Neuroendocrine Axis and Spinal Cord. J Neuroendocrinol 2016; 28:10.1111/jne.12401. [PMID: 27262161 PMCID: PMC4956521 DOI: 10.1111/jne.12401] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 06/03/2016] [Accepted: 06/03/2016] [Indexed: 12/13/2022]
Abstract
This review highlights the principal effects of steroid hormones at central and peripheral levels in the neuroendocrine axis. The data discussed highlight the principal role of oestrogens and testosterone in hormonal programming in relation to sexual orientation, reproductive and metabolic programming, and the neuroendocrine mechanism involved in the development of polycystic ovary syndrome phenotype. Moreover, consistent with the wide range of processes in which steroid hormones take part, we discuss the protective effects of progesterone on neurodegenerative disease and the signalling mechanism involved in the genesis of oestrogen-induced pituitary prolactinomas.
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Affiliation(s)
- L Zubeldia-Brenner
- Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Argentina
| | - C E Roselli
- Department of Physiology and Pharmacology, Oregon Health and Science University Portland, Portland, OR, USA
| | - S E Recabarren
- Laboratory of Animal Physiology and Endocrinology, Faculty of Veterinary Sciences, University of Concepcion, Chillán, Chile
| | - M C Gonzalez Deniselle
- Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Argentina
- Departamento de Ciencias Fisiológicas, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - H E Lara
- Laboratory of Neurobiochemistry Department of Biochemistry and Molecular Biology, Faculty of Chemical and Pharmaceutical Sciences, University of Chile, Santiago, Chile
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Theodros D, Patel M, Ruzevick J, Lim M, Bettegowda C. Pituitary adenomas: historical perspective, surgical management and future directions. CNS Oncol 2015; 4:411-29. [PMID: 26497533 DOI: 10.2217/cns.15.21] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Pituitary adenomas are among the most common central nervous system tumors. They represent a diverse group of neoplasms that may or may not secrete hormones based on their cell of origin. Epidemiologic studies have documented the incidence of pituitary adenomas within the general population to be as high as 16.7%. A growing body of work has helped to elucidate the pathogenesis of these tumors. Each subtype has been shown to demonstrate unique cellular changes potentially leading to tumorigenesis. Surgical advancements over several decades have included microsurgery and the employment of the endoscope for surgical resection. These advancements increase the likelihood of gross-total resection and have resulted in decreased patient morbidity.
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Affiliation(s)
- Debebe Theodros
- The Johns Hopkins University School of Medicine, The Johns Hopkins University Department of Neurosurgery, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - Mira Patel
- The Johns Hopkins University School of Medicine, The Johns Hopkins University Department of Neurosurgery, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - Jacob Ruzevick
- The Johns Hopkins University School of Medicine, The Johns Hopkins University Department of Neurosurgery, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - Michael Lim
- The Johns Hopkins University School of Medicine, The Johns Hopkins University Department of Neurosurgery, The Johns Hopkins Hospital, Baltimore, MD, USA
| | - Chetan Bettegowda
- The Johns Hopkins University School of Medicine, The Johns Hopkins University Department of Neurosurgery, The Johns Hopkins Hospital, Baltimore, MD, USA
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Monsalves E, Juraschka K, Tateno T, Agnihotri S, Asa SL, Ezzat S, Zadeh G. The PI3K/AKT/mTOR pathway in the pathophysiology and treatment of pituitary adenomas. Endocr Relat Cancer 2014; 21:R331-44. [PMID: 25052915 DOI: 10.1530/erc-14-0188] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pituitary adenomas are common intracranial neoplasms. Patients with these tumors exhibit a wide range of clinically challenging problems, stemming either from results of sellar mass effect in pituitary macroadenoma or the diverse effects of aberrant hormone production by adenoma cells. While some patients are cured/controlled by surgical resection and/or medical therapy, a proportion of patients exhibit tumors that are refractory to current modalities. New therapeutic approaches are needed for these patients. Activation of the AKT/phophotidylinositide-3-kinase pathway, including mTOR activation, is common in human neoplasia, and a number of therapeutic approaches are being employed to neutralize activation of this pathway in human cancer. This review examines the role of this pathway in pituitary tumors with respect to tumor biology and its potential role as a therapeutic target.
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Affiliation(s)
- Eric Monsalves
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, CanadaInstitute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
| | - Kyle Juraschka
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
| | - Toru Tateno
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
| | - Sameer Agnihotri
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
| | - Sylvia L Asa
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
| | - Shereen Ezzat
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, CanadaInstitute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, CanadaInstitute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
| | - Gelareh Zadeh
- Institute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, CanadaInstitute of Medical ScienceDepartment of Medical BiophysicsUniversity of Toronto, Toronto, Ontario, CanadaDivision of NeurosurgeryToronto Western Hospital, 399 Bathurst Street, 4W-439, Toronto, Ontario, Canada M5T 2S8Ontario Cancer InstitutePrincess Margaret Hospital, Toronto, Ontario, CanadaEndocrine Oncology Site GroupPrincess Margaret Hospital, Toronto, Ontario, CanadaDepartment of Laboratory Medicine and PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
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10
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Cristina C, Luque GM, Demarchi G, Lopez Vicchi F, Zubeldia-Brenner L, Perez Millan MI, Perrone S, Ornstein AM, Lacau-Mengido IM, Berner SI, Becu-Villalobos D. Angiogenesis in pituitary adenomas: human studies and new mutant mouse models. Int J Endocrinol 2014; 2014:608497. [PMID: 25505910 PMCID: PMC4251882 DOI: 10.1155/2014/608497] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/30/2014] [Indexed: 01/01/2023] Open
Abstract
The role of angiogenesis in pituitary tumor development has been questioned, as pituitary tumors have been usually found to be less vascularized than the normal pituitary tissue. Nevertheless, a significantly higher degree of vasculature has been shown in invasive or macropituitary prolactinomas when compared to noninvasive and microprolactinomas. Many growth factors and their receptors are involved in pituitary tumor development. For example, VEGF, FGF-2, FGFR1, and PTTG, which give a particular vascular phenotype, are modified in human and experimental pituitary adenomas of different histotypes. In particular, vascular endothelial growth factor, VEGF, the central mediator of angiogenesis in endocrine glands, was encountered in experimental and human pituitary tumors at different levels of expression and, in particular, was higher in dopamine agonist resistant prolactinomas. Furthermore, several anti-VEGF techniques lowered tumor burden in human and experimental pituitary adenomas. Therefore, even though the role of angiogenesis in pituitary adenomas is contentious, VEGF, making permeable pituitary endothelia, might contribute to adequate temporal vascular supply and mechanisms other than endothelial cell proliferation. The study of angiogenic factor expression in aggressive prolactinomas with resistance to dopamine agonists will yield important data in the search of therapeutical alternatives.
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Affiliation(s)
- Carolina Cristina
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
- CITNOBA (CONICET-UNNOBA), Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Monteagudo 2772, Pergamino, 2700 Buenos Aires, Argentina
| | - Guillermina María Luque
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
| | - Gianina Demarchi
- CITNOBA (CONICET-UNNOBA), Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Monteagudo 2772, Pergamino, 2700 Buenos Aires, Argentina
| | - Felicitas Lopez Vicchi
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
| | - Lautaro Zubeldia-Brenner
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
| | - Maria Ines Perez Millan
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
| | - Sofia Perrone
- CITNOBA (CONICET-UNNOBA), Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Monteagudo 2772, Pergamino, 2700 Buenos Aires, Argentina
| | - Ana Maria Ornstein
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
| | - Isabel M. Lacau-Mengido
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
| | - Silvia Inés Berner
- Servicio de Neurocirugía, Clínica Santa Isabel, Avenida Directorio 2037, C1406GZJ Buenos Aires, Argentina
- Servicio de Neurocirugía, Hospital Santa Lucía, Avenida San Juan 2021, C1232AAC Buenos Aires, Argentina
| | - Damasia Becu-Villalobos
- Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, 1428 Buenos Aires, Argentina
- *Damasia Becu-Villalobos:
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11
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Ezzat S, Asa SL. Mechanisms of pituitary tumorigenesis. Mol Oncol 2013. [DOI: 10.1017/cbo9781139046947.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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12
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Sabatino ME, Sosa LDV, Petiti JP, Mukdsi JH, Mascanfroni ID, Pellizas CG, Gutiérrez S, Torres AI, De Paul AL. Functional Toll-like receptor 4 expressed in lactotrophs mediates LPS-induced proliferation in experimental pituitary hyperplasia. Exp Cell Res 2013; 319:3020-34. [DOI: 10.1016/j.yexcr.2013.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/26/2013] [Accepted: 08/06/2013] [Indexed: 11/29/2022]
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13
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Ines M, Millán P, Cristina C, Berner SI, Becu-villalobos D. Prolactinomas: Role of VEGF, FGF-2 and CD31. In: Hayat M, editor. Tumors of the Central Nervous System, Volume 12. Dordrecht: Springer Netherlands; 2014. pp. 33-41. [DOI: 10.1007/978-94-007-7217-5_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Abstract
An 8-year-old, male neutered, domestic longhair cat was referred for investigation of insulin-resistant diabetes mellitus. Routine haematology, serum biochemistry, urinalysis (including culture), total T4 and urine creatinine:cortisol ratio were unremarkable, but markedly increased insulin-like growth factor-1 concentration was identified and a pituitary mass was subsequently documented. The cat was treated conservatively with the dopamine agonist L-deprenyl and was re-presented 16 months later for worsening polyuria, polydipsia, polyphagia, marked lumbar muscle atrophy, development of a pendulous abdomen and marked thinning of the abdominal skin. Hyperadrenocorticism was diagnosed based on abdominal ultrasonography, dexamethasone suppression testing and endogenous adrenocorticotropic hormone (ACTH). The cat was treated with trilostane (30 mg q24h PO) and showed some clinical improvement, but developed an opportunistic fungal infection and skin fragility syndrome 4.5 months after commencing treatment, and was euthanased. A double-pituitary adenoma comprising a discrete somatotroph adenoma and a separate plurihormonal adenoma (positive immunoreactivity for ACTH, melanocyte-stimulating hormone and follicle-stimulating hormone) was identified on post-mortem examination. These two pituitary adenomas were suspected to have arisen as independent neoplastic entities with the plurihormonal tumour either being clinically silent at the initial presentation or having developed over the subsequent 16 months.
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Affiliation(s)
- Mellora Sharman
- Department of Veterinary Clinical Sciences, School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA, Australia
- Faculty of Veterinary Science, University of Melbourne, Werribee, VIC, Australia
- Mellora Sharman is currently affiliated with the Faculty of Veterinary Science, University of Melbourne, Werribee, VIC, Australia
| | - Louise FitzGerald
- Department of Veterinary Clinical Sciences, School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA, Australia
- Louise FitzGerald is currently affiliated with the Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Matti Kiupel
- Diagnostic Center for Population and Animal Health, Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
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15
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Mezzomo LC, Gonzales PH, Pesce FG, Kretzmann Filho N, Ferreira NP, Oliveira MC, Kohek MBF. Expression of cell growth negative regulators MEG3 and GADD45γ is lost in most sporadic human pituitary adenomas. Pituitary 2012; 15:420-7. [PMID: 21850407 DOI: 10.1007/s11102-011-0340-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We aimed at the evaluation of MEG3 and GADD45γ expression in sporadic functioning and clinically non-functioning human pituitary adenomas, morphologically characterized by immunohistochemistry analysis and their association with clinical features. Thirty eight patients who had undergone hypophysectomy at São José Hospital of Irmandade Santa Casa de Misericórdia in Porto Alegre, Brazil, were included in this study. We evaluated tumor-type specific MEG3 and GADD45γ expression by qRT-PCR in the pituitary adenomas, and its association with clinical features, as age, gender and tumor size, obtained from medical records. The patients consisted of 21 males and 17 females and the mean age was 47 ± 14 (mean ± SD), ranging from 18 to 73 years-old. Of these 14 were clinically non-functioning, 10 GH-secreting, 9 PRL-secreting, and 5 ACTH-secreting pituitary adenomas. All samples were macroadenomas, except four ACTH-secreting tumors, which were microadenomas. In summary, MEG3 and GADD45γ expression was significantly lost in most clinically non-functioning adenomas (78 and 92%, respectively). Other assessed pituitary tumor phenotypes expressed both genes at significantly different levels, and, in some cases, with overexpression. There was no significant association between gene expression and the analyzed clinical features. Our results confirm the previous report, which indicated that MEG3 and GADD45γ expression is lost in the majority of human pituitary tumors, mainly in clinically-nonfunctioning adenomas. Functioning tumors had differences of relative expression levels. The two groups of tumors are probably genetically different and may have a different natural history.
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Affiliation(s)
- Lisiane Cervieri Mezzomo
- Post Graduation Program of Pathology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, CEP 90050-170, Brazil
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16
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Abstract
The pituitary gland plays a prominent role in the control of many physiological processes. This control is achieved through the actions and interactions of hormones and growth factors that are produced and secreted by the endocrine cell types and the non-endocrine constituents that collectively and functionally define this complex organ. The five endocrine cell types of the anterior lobe of the pituitary, somatotropes, lactotropes, corticotropes, thyrotropes and gonadotropes, are defined by their primary product, growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH) and follicle stimulating hormone (FSH)/luteinizing hormone (LH). They are further distinguishable by the presence of cell surface receptors that display high affinity and selectivity for specific hypothalamic hormones and couple to appropriate downstream signaling pathways involved in the control of cell type specific responses, including the release and/or synthesis of pituitary hormones. Central control of the pituitary via the hypothalamus is further fine-tuned by the positive or negative actions of peripheral feedback signals and of a variety of factors that originate from sources within the pituitary. The focus of this review is the latter category of intrinsic factors that exert local control. Special emphasis is given to the TGF-β family of growth factors, in particular activin effects on the gonadotrope population, because a considerable body of evidence supports their contribution to the local modulation of the embryonic and postnatal pituitary as well as pituitary pathogenesis. A number of other substances, including members of the cytokine and FGF families, VEGF, IGF1, PACAP, Ghrelin, adenosine and nitric oxide have also been shown or implicated to function as autocrine/paracrine factors, though, definitive proof remains lacking in some cases. The ever-growing list of putative autocrine/paracrine factors of the pituitary nevertheless has highlighted the complexity of the local network and its impact on pituitary functions.
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Affiliation(s)
- Louise M Bilezikjian
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California, USA
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17
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Dallago CM, Barbosa-Coutinho LM, Ferreira NP, Meurer R, Pereira-Lima JFS, Oliveira MDC. Determination of cell proliferation using Mcm2 antigen and evaluation of apoptosis and TGF-beta1 expression in GH-secreting or clinically nonfunctioning pituitary adenomas. Endocr Pathol 2010; 21:32-9. [PMID: 20174894 DOI: 10.1007/s12022-010-9107-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Pituitary adenomas (PA) occasionally show aggressive behavior, with invasion of the surrounding tissues. The identification of markers able to recognize aggressive PA in early stages remains a challenge. We aimed to determine the expression of a new cell proliferation marker, Mcm2, and the presence of apoptosis in PA, and to evaluate the association of clinicopathological features with the apoptotic and proliferative indices. Additionally, the TGF-beta1 expression, an inducer of apoptosis, was determined. The proliferative index was determined in GH-secreting or clinically nonfunctioning PA using immunohistochemical (IH) methods for Mcm2 and Ki-67 antigens. The apoptosis was assessed by the TUNEL method and the TGF-beta1 expression by IH. A significant positive correlation was found between log Mcm2 index and log Ki-67 index (p < 0.001). Mcm2 and Ki-67 detected a similar number of proliferating cells. Mcm2 index showed a significant association with tumor extension (p = 0.02), but not with tumor invasion. Apoptosis was detected in 17% of the adenomas, with a maximum apoptotic index of 0.77%. Immunoreactivity to TGF-beta1 was observed in 77% of the adenomas, showing an association with tumor extension. We concluded that, in this sample, Mcm2 was similar to Ki-67 in the identification of the proliferating cells and that apoptosis was rare.
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Affiliation(s)
- Cristina Micheletto Dallago
- Neuroendocrinology Center, Complexo Hospitalar Santa Casa, Universidade Federal de Ciências da Saúde de Porto Alegre (UFSCPA), Rua Dona Mimi Moro, 40, 90480-050, Porto Alegre, RS, Brazil
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18
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Ben-Jonathan N, Chen S, Dunckley JA, LaPensee C, Kansra S. Estrogen receptor-alpha mediates the epidermal growth factor-stimulated prolactin expression and release in lactotrophs. Endocrinology 2009; 150:795-802. [PMID: 18832099 PMCID: PMC2646526 DOI: 10.1210/en.2008-0756] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Epidermal growth factor (EGF) is a potent regulator of cell function in many cell types. EGF-receptor (EGFR/ErbB1)-activated Erk1/2 has been reported to activate estrogen receptor (ER) in an estrogen (E2)-independent manner. In the pituitary lactotrophs, both EGF and E2 stimulate prolactin (PRL) release, but the nature of interactions between ErbB and ERalpha signaling is unknown. Our objectives were to 1) characterize EGF-induced PRL release, 2) determine whether this effect requires ERalpha, and 3) determine the molecular basis for cross talk between ErbB and ERalpha signaling pathways. Using GH3 cells, a rat lactotroph cell line, we report that EGF stimulates PRL gene expression and release in a dose- and time-dependent manner. EGF caused a rapid and robust activation of Erk1/2 via ErbB1 and induced phosphorylation of S118 on ERalpha in an Erk1/2-dependent manner. The global antiestrogen ICI 182780 and the ERalpha-specific antagonist 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylet hoxy)phenol]-1H-pyrazole dihydrochloride (MPP), but not the ERbeta-specific antagonist 4-[2-Phenyl-5,7-bis(trifluoromethyl) pyrazolo[1,5-a]pyrimidin-3-yl]phenol (PHTPP), blocked the EGF-induced PRL release, indicating an ERalpha requirement. This was further supported by using ERalpha knockdown by small interfering RNA. Because the antiestrogens did not block EGF-induced Mek-1 or Erk1/2 phosphorylation, ERalpha is placed downstream from the ErbB1-activated Erk1/2. These results provide the first evidence that ErbB1-induced PRL release is ERalpha dependent.
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Affiliation(s)
- Nira Ben-Jonathan
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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19
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Höpfner M, Schuppan D, Scherübl H. Treatment of gastrointestinal neuroendocrine tumors with inhibitors of growth factor receptors and their signaling pathways: recent advances and future perspectives. World J Gastroenterol 2008; 14:2461-73. [PMID: 18442192 PMCID: PMC2708356 DOI: 10.3748/wjg.14.2461] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Revised: 03/15/2008] [Indexed: 02/06/2023] Open
Abstract
The limited efficacy of conventional cytotoxic treatment regimes for advanced gastrointestinal neuroendocrine cancers emphasizes the need for novel and more effective medical treatment options. Recent findings on the specific biological features of this family of neoplasms has led to the development of new targeted therapies, which take into account the high vascularization and abundant expression of specific growth factors and cognate tyrosine kinase receptors. This review will briefly summarize the status and future perspectives of antiangiogenic, mTOR- or growth factor receptor-based pharmacological approaches for the innovative treatment of gastrointestinal neuroendocrine tumors. In view of the multitude of novel targeted approaches, the rationale for innovative combination therapies, i.e. combining growth factor (receptor)-targeting agents with chemo- or biotherapeutics or with other novel anticancer drugs such as HDAC or proteasome inhibitors will be taken into account.
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20
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Abstract
Living organisms represent, in essence, dynamic interactions of high complexity between membrane-separated compartments that cannot exist on their own, but reach behaviour in co-ordination. In multicellular organisms, there must be communication and co-ordination between individual cells and cell groups to achieve appropriate behaviour of the system. Depending on the mode of signal transportation and the target, intercellular communication is neuronal, hormonal, paracrine or juxtacrine. Cell signalling can also be self-targeting or autocrine. Although the notion of paracrine and autocrine signalling was already suggested more than 100 years ago, it is only during the last 30 years that these mechanisms have been characterised. In the anterior pituitary, paracrine communication and autocrine loops that operate during fetal and postnatal development in mammals and lower vertebrates have been shown in all hormonal cell types and in folliculo-stellate cells. More than 100 compounds have been identified that have, or may have, paracrine or autocrine actions. They include the neurotransmitters acetylcholine and gamma-aminobutyric acid, peptides such as vasoactive intestinal peptide, galanin, endothelins, calcitonin, neuromedin B and melanocortins, growth factors of the epidermal growth factor, fibroblast growth factor, nerve growth factor and transforming growth factor-beta families, cytokines, tissue factors such as annexin-1 and follistatin, hormones, nitric oxide, purines, retinoids and fatty acid derivatives. In addition, connective tissue cells, endothelial cells and vascular pericytes may influence paracrinicity by delivering growth factors, cytokines, heparan sulphate proteoglycans and proteases. Basement membranes may influence paracrine signalling through the binding of signalling molecules to heparan sulphate proteoglycans. Paracrine/autocrine actions are highly context-dependent. They are turned on/off when hormonal outputs need to be adapted to changing demands of the organism, such as during reproduction, stress, inflammation, starvation and circadian rhythms. Specificity and selectivity in autocrine/paracrine interactions may rely on microanatomical specialisations, functional compartmentalisation in receptor-ligand distribution and the non-equilibrium dynamics of the receptor-ligand interactions in the loops.
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Affiliation(s)
- C Denef
- Laboratory of Cell Pharmacology, University of Leuven, Medical School, Leuven, Belgium.
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21
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Spuch C, Diz-Chaves Y, Pérez-Tilve D, Alvarez-Crespo M, Mallo F. Prolactin-releasing Peptide (PrRP) increases prolactin responses to TRH in vitro and in vivo. Endocrine 2007; 31:119-24. [PMID: 17873321 DOI: 10.1007/s12020-007-0031-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Revised: 05/17/2007] [Accepted: 05/17/2007] [Indexed: 11/25/2022]
Abstract
The Prolactin-releasing Peptide (PrRP) is a 31-aminoacid peptide produced and secreted from the hypothalamus, and postulated to promote the prolactin release from the pituitary. However, the action of PrRP remain controversial, since it was described to have potency comparable enough to TRH, although there are many evidences that PrRP is less potent than TRH. Here we have studied the effects of PrRP alone or in combination with TRH in the prolactin levels of rat pituitary primary cell cultures in vitro and also in vivo prolactin responses in randomly cycling and estrogens-treated female rats. PrRP itself increased prolactin levels in vitro and in vivo, although in a magnitude several times lower than TRH. In vivo PrRP promotes an atypical non-peaking progressive and maintained prolactin increase. On the other hand, PrRP markedly increased the prolactin responses to TRH in vitro (10-30 fold increase) and in vivo (up to three-fold increase). In addition, FGF-2 and EGF, two important growth factors present in the pituitary, reduced the PrRP-induced prolactin increase in vitro. Taken together our results suggest that PrRP released from the hypothalamus may be relevant to modulate the circulating prolactin levels in the rat.
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Affiliation(s)
- Carlos Spuch
- Department of Functional Biology and Health Sciences, Laboratory of Endocrinology, Faculty of Sciences, Campus of Vigo, University of Vigo, Vigo, 36310, Spain.
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22
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Cristina C, Díaz-Torga GS, Goya RG, Kakar SS, Perez-Millán MI, Passos VQ, Giannella-Neto D, Bronstein MD, Becu-Villalobos D. PTTG expression in different experimental and human prolactinomas in relation to dopaminergic control of lactotropes. Mol Cancer 2007; 6:4. [PMID: 17222350 PMCID: PMC1779802 DOI: 10.1186/1476-4598-6-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Accepted: 01/12/2007] [Indexed: 11/18/2022] Open
Abstract
Background Pituitary tumor transforming gene (pttg) is a novel oncogene that is expressed at higher level in most of the tumors analyzed to date compared to normal tissues. Nevertheless, its expression in prolactinomas and its relation with the pituitary dopamine receptor 2 (D2R) are not well defined. We sought to determine the pituitary level of pttg in three different experimental models of prolactinomas with altered dopaminergic control of the pituitary: the dopaminergic D2R knockout female mouse, the estrogen-treated rat, and the senescent female rat. These three models shared the characteristics of increased pituitary weight, hyperprolactinemia, lactotrope hyperplasia and reduced or absent dopaminergic action at the pituitary level. We also studied samples from human macroprolactinomas, which were characterized as responsive or resistant to dopamine agonist therapy. Results When compared to female wild-type mice, pituitaries from female D2R knockout mice had decreased PTTG concentration, while no difference in pttg mRNA level was found. In senescent rats no difference in pituitary PTTG protein expression was found when compared to young rats. But, in young female rats treated with a synthetic estrogen (Diethylstylbestrol, 20 mg) PTTG protein expression was enhanced (P = 0.029). Therefore, in the three experimental models of prolactinomas, pituitary size was increased and there was hyperprolactinemia, but PTTG levels followed different patterns. Patients with macroprolactinomas were divided in those in which dopaminergic therapy normalized or failed to normalize prolactin levels (responsive and resistant, respectively). When pituitary pttg mRNA level was analyzed in these macroprolactinomas, no differences were found. We next analyzed estrogen action at the pituitary by measuring pituitary estrogen receptor α levels. The D2R knockout female mice have low estrogen levels and in accordance, pituitary estrogen receptors were increased (P = 0.047). On the other hand, in senescent rats estrogen levels were slightly though not significantly higher, and estrogen receptors were similar between groups. The estrogen-treated rats had high pharmacological levels of the synthetic estrogen, and estrogen receptors were markedly lower than in controls (P < 0.0001). Finally, in patients with dopamine resistant or responsive prolactinomas no significant differences in estrogen receptor α levels were found. Therefore, pituitary PTTG was increased only if estrogen action was increased, which correlated with a decrease in pituitary estrogen receptor level. Conclusion We conclude that PTTG does not correlate with prolactin levels or tumor size in animal models of prolactinoma, and its pituitary content is not related to a decrease in dopaminergic control of the lactotrope, but may be influenced by estrogen action at the pituitary level. Therefore it is increased only in prolactinomas generated by estrogen treatment, and not in prolactinomas arising from deficient dopamine control, or in dopamine resistant compared with dopamine responsive human prolactinomas. These results are important in the search for reliable prognostic indicators for patients with pituitary adenomas which will make tumor-specific therapy possible, and help to elucidate the poorly understood phenomenon of pituitary tumorigenesis.
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Affiliation(s)
- Carolina Cristina
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas. V. Obligado 2490. (1428) Buenos Aires. Argentina
| | - Graciela S Díaz-Torga
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas. V. Obligado 2490. (1428) Buenos Aires. Argentina
| | - Rodolfo G Goya
- Institute for Biochemical Research-Histology B, Faculty of Medicine, University of La Plata, Argentina
| | - Sham S Kakar
- Department of Medicine, James Graham Brown Cancer Center. University of Louisville, Louisville, KY, USA
| | - María I Perez-Millán
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas. V. Obligado 2490. (1428) Buenos Aires. Argentina
| | - Vanessa Q Passos
- Neuroendocrine Unit, Division of Endocrinology and Metabolism, Hospital das Clinicas. University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Daniel Giannella-Neto
- Laboratory for Cellular and Molecular Endocrinology (LIM 25), Hospital das Clinicas. University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Marcello D Bronstein
- Neuroendocrine Unit, Division of Endocrinology and Metabolism, Hospital das Clinicas. University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Damasia Becu-Villalobos
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas. V. Obligado 2490. (1428) Buenos Aires. Argentina
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23
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Sidibe EH. [Hypergonadotropic hypogonadism with sella turcica tumor syndrome: gonadotropic adenoma?]. Ann Endocrinol (Paris) 2006; 67:348-52. [PMID: 17072241 DOI: 10.1016/s0003-4266(06)72610-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A 43-year-old patient, known for infertility for ten years, presented hypogonadism (low libido, impotence, low testosteronemia) with hypergonadotropism (high FSH contrasting with low LH) and a tumor syndrome of the sella turcica. The biological, immunohistochemical and clinical features of gonadotropic adenoma are presented.
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Affiliation(s)
- E H Sidibe
- Centre médical Marc Sankalé--B.P. 5062, Fann, Dakar, Sénégal.
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Mukdsi JH, De Paul AL, Petiti JP, Gutiérrez S, Aoki A, Torres AI. Pattern of FGF-2 isoform expression correlated with its biological action in experimental prolactinomas. Acta Neuropathol 2006; 112:491-501. [PMID: 16823503 DOI: 10.1007/s00401-006-0101-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 06/08/2006] [Accepted: 06/08/2006] [Indexed: 11/28/2022]
Abstract
Fibroblast growth factor-2 (FGF-2) synthesized in the pituitary is involved in the formation and progression of pituitary tumors. The aim of this study was to analyze the pattern expression of two FGF-2 isoforms at different subcellular levels and to determine its correlation with prolactinoma development. Estrogen administration to male rats for 7, 20, and 60 days generated pituitary tumors, with lactotrophs being the prevalent cell type. Ultrastructural immunolabeling showed FGF-2 in the cytosolic and nuclear compartments of somatotrophs, lactotrophs and gonadotrophs, as well as in folliculo-stellate cells of normal rats. Estrogen stimulation increased FGF-2 immunoreactivity in various tumors and enhanced the expression of two FGF-2 isoforms, 18 and 22 kDa, as quantified by western blot. The 18 kDa isoform observed in cytosol extracts reached the highest levels after 60 days of hormonal stimulation and this was related to lactotroph proliferation. However, the 22 kDa FGF-2 isoform was only detected in the nuclear compartment and achieved the maximum expression at 7 days of estrogen treatment, without any correlation with lactotroph proliferation. These results suggest that the 18 kDa FGF-2 may play a role in the modulation of lactotroph proliferation in prolactinomas induced by estrogen. The overproduction of both FGF-2 isoforms appears to be implicated in autocrine-paracrine-intracrine mitogenic loops; this FGF-2 activity could lead to uncontrolled cell growth, angiogenesis, and tumor formation.
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Affiliation(s)
- Jorge H Mukdsi
- Centro de Microscopía Electrónica, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Haya de la Torre, Pabellón de Biología Celular, Ciudad Universitaria, X5000, HRA, Córdoba, Argentina
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25
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Abstract
Activins, as members of the transforming growth factor-β superfamily, control and orchestrate many physiological processes and are vital for the development, growth and functional integrity of most tissues, including the pituitary. Activins produced by pituitary cells work in conjunction with central, peripheral, and other local factors to influence the function of gonadotropes and maintain a normal reproductive axis. Follistatin, also produced by the pituitary, acts as a local buffer to bind activin and modulate its bioactivity. On the other hand, inhibins of gonadal origin provide an endocrine feedback signal to antagonize activin signaling in cells that express the inhibin co-receptor, betaglycan, such as gonadotropes. This review highlights the pituitary roles of activin and the mechanisms through which these actions are modulated by inhibin and follistatin.
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Affiliation(s)
- Louise M Bilezikjian
- The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, 10010 N. Torrey Pines Road, La Jolla, California 92037, USA.
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26
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Ezzat S, Zheng L, Winer D, Asa SL. Targeting N-cadherin through fibroblast growth factor receptor-4: distinct pathogenetic and therapeutic implications. Mol Endocrinol 2006; 20:2965-75. [PMID: 16857743 DOI: 10.1210/me.2006-0223] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Several molecular aberrations have been implicated in the pathogenesis of pituitary tumors, but few have proven thus far to be of therapeutic value. Pituitary tumor-derived fibroblast growth factor receptor-4 (ptd-FGFR4) is an alternatively transcribed cytoplasmic isoform lacking most of the extracellular domain. This oncogene recapitulates the morphological features of human pituitary tumors in transgenic mice. To investigate the therapeutic potential of targeting ptd-FGFR4, we examined the impact of FGFR4 tyrosine kinase inhibition in xenografted mice. GH4 pituitary cells expressing ptd-FGFR4 develop into invasive tumors. Systemic treatment of mice bearing ptd-FGFR4 tumors with the FGFR-selective inhibitor PD173074 resulted in recovery of membranous N-cadherin staining and a significant reduction in tumor volume with less invasive growth behavior. Mutation of tyrosine Y754F in ptd-FGFR4 abrogated the effect of PD173074-mediated inhibition. The pivotal role of N-cadherin as a mediator of this pituitary cell growth was demonstrated by small interfering RNA mediated down-regulation, which promoted invasive growth in xenografted mice. To validate this model in primary human pituitary tumors, we examined the expression of ptd-FGFR4, N-cadherin, and clinical behavior. Loss of membranous N-cadherin correlated with cytoplasmic FGFR4 expression and with tumor invasiveness in surgically resected human pituitary tumors. Primary human pituitary tumor cells treated with PD173074 showed restoration of N-cadherin to the membrane with dephosphorylation of retinoblastoma protein. These data highlight the pathogenetic significance of N-cadherin misexpression and emphasize the importance of FGFR partnership in mediating its functions.
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MESH Headings
- Adenoma/drug therapy
- Adenoma/etiology
- Adenoma/metabolism
- Animals
- Antineoplastic Agents/therapeutic use
- Brain Neoplasms/metabolism
- Cadherins/metabolism
- Cadherins/physiology
- Cell Proliferation/drug effects
- Cells, Cultured
- Disease Progression
- Female
- Gene Expression Regulation, Neoplastic
- Humans
- Mice
- Mice, SCID
- Models, Biological
- Neoplasm Invasiveness
- Neoplasm Proteins/antagonists & inhibitors
- Neoplasm Proteins/physiology
- Pituitary Neoplasms/drug therapy
- Pituitary Neoplasms/etiology
- Pituitary Neoplasms/metabolism
- Protein Isoforms/antagonists & inhibitors
- Protein Isoforms/physiology
- Protein Kinase Inhibitors/therapeutic use
- Pyrimidines/pharmacology
- Pyrimidines/therapeutic use
- Rats
- Receptor, Fibroblast Growth Factor, Type 4/antagonists & inhibitors
- Receptor, Fibroblast Growth Factor, Type 4/metabolism
- Receptor, Fibroblast Growth Factor, Type 4/physiology
- Somatotrophs
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Shereen Ezzat
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
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27
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Abstract
Pituitary tumors are the most common primary intracranial neoplasms. Although most pituitary tumors are considered typically benign, others can cause severe and progressive disease. The principal aims of pituitary tumor treatment are the elimination or reduction of the tumor mass, normalization of hormone secretion and preservation of remaining pituitary function. In spite of major advances in the therapy of pituitary tumors, for some of the most difficult tumors, current therapies that include medical, surgical and radiotherapeutic methods are often unsatisfactory and there is a need to develop new treatment strategies. Gene therapy, which uses nucleic acids as drugs, has emerged as an attractive therapeutic option for the treatment of pituitary tumors that do not respond to classical treatment strategies if the patients become intolerant to the therapy. The development of animal models for pituitary tumors and hormone hypersecretion has proven to be critical for the implementation of novel treatment strategies and gene therapy approaches. Preclinical trials using several gene therapy approaches for the treatment of anterior pituitary diseases have been successfully implemented. Several issues need to be addressed before clinical implementation becomes a reality, including the development of more effective and safer viral vectors, uncovering novel therapeutic targets and development of targeted expression of therapeutic transgenes. With the development of efficient gene delivery vectors allowing long-term transgene expression with minimal toxicity, gene therapy will become one of the most promising approaches for treating pituitary adenomas.
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Affiliation(s)
- Adriana Seilicovich
- Centro de Investigaciones en Reproducción, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Buenos Aires (C1121ABG), Argentina.
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28
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Mukdsi JH, De Paul AL, Gutiérrez S, Roth FD, Aoki A, Torres AI. Subcellular localisation of VEGF in different pituitary cells. Changes of its expression in oestrogen induced prolactinomas. J Mol Histol 2006; 36:447-54. [PMID: 16733790 DOI: 10.1007/s10735-005-9012-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2005] [Accepted: 11/23/2005] [Indexed: 01/06/2023]
Abstract
Vascular endothelial growth factor (VEGF) is an important angiogenic factor in the pituitary gland. The objective of this study was to unveil the VEGF subcellular localisation in different pituitary cell types and to evaluate changes in its expression at different time intervals after oestrogen stimulation. A relevant feature demonstrated was the identification of this cytokine in the nucleus and cytoplasm of lactotrophs, somatotrophs and gonadotrophs, as well as in follicle-stellate cells of male rats. Oestrogen treatment increased the number of VEGF immunopositive cells and its expression detected differentially by western blot in both nucleus and cytoplasm of pituitary cells when compared to the control. At ultrastructural level VEGF appeared associated with nucleolus and euchromatin involving a possible internal autocrine loop. In lactotrophs, the predominant cell of the tumour, VEGF was immunodetected in RER, Golgi complex, and vesicular organelles, supporting further the association with an auto-paracrine effect exerted by VEGF. The nucleus/cytoplasm ratio of VEGF revealed a prevalent accumulation of VEGF in the cytoplasm. The presence of VEGF in the nucleus may probably be associated with a translocation to this cell compartment. This study demonstrated a cytoplasmic and nuclear immunolocalisation of VEGF in normal and tumoural adenohypophyseal cells. In the course of prolactinoma development, the oestrogen stimulated VEGF expression in tumoural cells, promoting a vascular adaptation which contributes to growth and progression of the tumour.
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Affiliation(s)
- Jorge Humberto Mukdsi
- Centro de Microscopía Electrónica, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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29
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Abstract
The anterior pituitary is made up of a number of cell types that are essential for such physiological processes as growth, development, homeostasis, metabolism, and reproduction. These include the hormonal cells corticotropes, thyrotropes, gonadotropes, somatotropes, lactotropes and a small population of mammosomatotropes, together with a non-hormonal cell type called the folliculo-stellate cells. The anterior pituitary hormonal cells are highly differentiated and are committed very early on during embryonic development. Their development is tightly regulated by both extrinsic signals as well as by endogenous gene expression. Many transcription factors that shape the development and functions of the anterior pituitary cells have been identified. Even after differentiation, pituitary cells continue to undergo mitosis and this process could be augmented under certain conditions in adulthood. Some anterior pituitary cells are multifunctional and exhibit mixed phenotypes. Pituitary tumors, which are mostly monoclonal in nature, are rather common. The molecular pathogenesis of pituitary tumorigenesis involves complex and diverse mechanisms. Aberrant intra- and extra-pituitary factors are involved. Mutations of some genes specific to pituitary tumors also play a role.
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Affiliation(s)
- Chung-Man Yeung
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
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30
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Abstract
Genetics and proteomics determine structure and function of normal tissues, and the molecular alterations that underlie tumorigenesis result in changes in these aspects of tissue biology in neoplasms. We review the known genetic alterations in pituitary tumors. These include the oncogenic Gsalpha protein (GSP)-activating mutations, and pituitary tumor-derived fibroblast growth factor receptor-4 (ptd-FGFR4), as well as tumor suppressor gene mutations associated with multiple endocrine neoplasia type 1 (MEN1). Other candidates identified from expression profiling include pituitary tumor-transforming gene (PTTG), GADD45, and bone morphogenic protein (BMP)4. Proteomic changes in pituitary tumors include classical alterations identified by immunohistochemistry as well as epigenetic reductions in p27. The underlying mechanisms for dysregulated cell adhesive molecules including cadherins and FGFRs are reviewed. The combined use of genetic and proteomic approaches will enhance novel drug therapeutic development.
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Affiliation(s)
- Sylvia L Asa
- Endocrine Oncology Site Group, Mount Sinai and Princess Margaret Hospitals, University of Toronto, Toronto, Ontario, Canada.
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31
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Abstract
Pituitary adenomas are common tumors composed of adenohypophysial cells. Although they usually arise in the sella turcica, they may occasionally be ectopic. Pituitary adenomas are rarely diagnosed in childhood and adolescence, but their mass effect and endocrine abnormalities can compromise both quality and length of life. Many signs or symptoms of pituitary adenoma, complained of in adulthood, not became evident during adolescence, suggesting true prevalence of this tumor in teenagers is higher than expected. Pititury adenoma occuring during adolescence are associated with features or therapeutic needs sometimes different from those occuring in adulthood. At the onset of disease, delay in growth was rarely observed in teenagers with pituitary adenomas. Many girls complain of oligoamenorrhoea and galactorrhoea, while headache and delay in pubertal development are the most commons features in boys. Hypopituitarism is occasionally encountered in adolescence. Early diagnosis and appropriate choice of therapy are necessary to avoid permanent endocrine complications of disease and its treatment.
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Affiliation(s)
- S K Singh
- Department of Endocrinology & Metabolism, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India.
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32
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Abstract
Recent advances in molecular pathology have shed light not only on the cellular composition and derivation of various tumors, but also on their growth potential, likelihood of recurrence, and prognosis. The development of reliable and prognostically informative methods of assessing tumor behavior is particularly important in pituitary tumors, where no precise correlation exists between morphology and clinical aggressiveness. Among the numerous morphologic techniques that have been introduced in the last three decades, some have gained popularity due to their reliability and ease of performance, whereas others have fallen from favor due to their inconsistency and insensitivity in distinguishing indolent from aggressive pituitary tumors. Yet others, due to cost and complexity, never came into general use. We predict that the immunohistochemical methods now in use for assessment of tumor behavior will be complemented and partly replaced by molecular genetic procedures in the future.
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Affiliation(s)
- Agustinus Suhardja
- Department of Radiology, SUNY Downstate Medical Center, Brooklyn, NY 11203-2098, USA.
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33
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Abstract
The precise regulation of the anterior pituitary is achieved by the cell-specific and combined actions of central, peripheral and local factors. Activins, inhibins, and follistatins were first discovered as gonadal factors with actions on FSH production from pituitary gonadotropes. With the realization that these factors are expressed in a wide array of tissues, including the pituitary, it became apparent that the functional importance of activins, inhibins, and follistatins extends beyond the reproductive axis and that they often exert their effects by autocrine/paracrine mechanisms. As members of the TGF-beta superfamily, activins and inhibins control and orchestrate many physiological processes and are vital for the development, the growth, and the functional integrity of most tissues, including the pituitary. Activins exert effects on multiple pituitary cell types but the best-characterized pituitary targets of the autocrine/paracrine function of activins are the gonadotropes. The autocrine/paracrine function of the activin-binding proteins, follistatins, constitutes an important local mechanism to modulate activin bioactivity while the restricted actions of gonadal inhibins to betaglycan-expressing gonadotropes provides a secondary mode of regulation of cell-specific actions of activins. The aim of this review is to highlight and evaluate experimental evidence that supports the roles of activins, inhibins, and follistatins as autocrine, paracrine, and/or endocrine modulators of the pituitary.
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Affiliation(s)
- Louise M Bilezikjian
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, 10010 N. Torrey Pines Road, La Jolla, CA 92037, USA.
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34
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Qian ZR, Sano T, Asa SL, Yamada S, Horiguchi H, Tashiro T, Li CC, Hirokawa M, Kovacs K, Ezzat S. Cytoplasmic expression of fibroblast growth factor receptor-4 in human pituitary adenomas: relation to tumor type, size, proliferation, and invasiveness. J Clin Endocrinol Metab 2004; 89:1904-11. [PMID: 15070963 DOI: 10.1210/jc.2003-031489] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The pathogenesis of pituitary adenomas remains unknown. A pituitary tumor-derived (ptd) isoform of fibroblast growth factor receptor-4 (ptd-FGFR4) has been implicated in the neoplastic process. To further understand the expression of FGFR4 in sporadic human pituitary adenomas, we studied 137 pituitary adenomas of various types (102 adenomas from Japanese patients and 35 adenomas from Canadian patients) and 10 nontumorous pituitaries using a polyclonal antiserum that recognizes the C terminus of FGFR4 and analyzed possible relationships among expression of FGFR4, patient nationality, tumor type, size, invasion, and the labeling index of the proliferation marker Ki-67 using the MIB-1 antibody. Cytoplasmic expression of FGFR4 protein was observed in 57.8% of Japanese cases and 62.8% of Canadian cases. FGFR4 reactivity was absent in all 10 normal adenohypophysial tissues examined. FGFR4 expression in pituitary adenomas was restricted mainly to the cytoplasm, a pattern similar to that seen in rat pituitary cells transfected with human ptd-FGFR4 but different from that of cells transfected with wild-type FGFR4, which displayed membrane localization of staining. Protein from primary human adenomas migrated as a 65-kDa species consistent with the predicted size of ptd-FGFR4. FGFR4 protein expression was frequently found in adenomas containing GH, ACTH, or FSH/LH and was also found in null cell adenomas, but reactivity was relatively rare in prolactin-containing adenomas in both Japanese and Canadian groups. The expression of FGFR4 protein was stronger in macroadenomas than in microadenomas (P = 0.02) and high levels of FGFR4 expression (moderate or greater density staining) were more frequently observed in macroadenomas than in microadenomas (P < 0.05). High levels of FGFR4 expression also correlated significantly with the proliferation marker Ki-67 (P = 0.002) and tended (but not significantly) to be found in invasive tumors. These data are consistent with a role for ptd-FGFR4 in pituitary tumorigenesis in a majority of human pituitary adenomas. Moreover, detection of FGFR4 cytoplasmic staining may provide an ancillary diagnostic tool in the diagnosis of pituitary adenoma, particularly in equivocal cases.
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Affiliation(s)
- Zhi Rong Qian
- Department of Pathology, University of Tokushima School of Medicine, Tokushima, Japan
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35
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Affiliation(s)
- Shereen Ezzat
- Department of Medicine, University of Toronto, Ontario, Canada M5G-1X5
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36
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Höpfner M, Sutter AP, Gerst B, Zeitz M, Scherübl H. A novel approach in the treatment of neuroendocrine gastrointestinal tumours. Targeting the epidermal growth factor receptor by gefitinib (ZD1839). Br J Cancer 2003; 89:1766-75. [PMID: 14583782 PMCID: PMC2394425 DOI: 10.1038/sj.bjc.6601346] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Therapeutic options to inhibit the growth and spread of neuroendocrine (NE) gastrointestinal tumours are still limited. Since gefitinib (4-(3-chloro-4-fluoroanilino)-7-methoxy-6-(3-morpholinopropoxy)quinazoline), an inhibitor of epidermal growth factor receptor-sensitive tyrosine kinase (EGFR-TK), had been shown to suppress potently the growth of various non-NE tumour entities, we studied the antineoplastic potency of gefitinib in NE gastrointestinal tumour cells. In human insulinoma (CM) cells, in human pancreatic carcinoid (BON) cells and in NE tumour cells of the gut (STC-1), gefitinib induced a time- and dose-dependent growth inhibition by almost 100%. The antiproliferative potency of gefitinib correlated with the proliferation rate of the tumour cells. So the IC50 value of gefitinib was 4.7±0.6 μM in the fast-growing CM cells, still 16.8±0.4 μM in the moderate-growing BON cells, and up to 31.5±2.5 μM in the slow-growing STC-1 cells. Similarly, the induction of apoptosis and cell-cycle arrest by gefitinib differed according to growth characteristics: fast-growing CM cells displayed a strong G0/G1 arrest in response to gefitinib, while no significant cell-cycle alterations were seen in the slow-growing STC-1. Vice versa, the proapoptotic effects of gefitinib, as determined by caspase-3 activation and DNA fragmentation, were most pronounced in the slow-growing STC-1 cells. Using cDNA microarrays, we found extensive changes in the expression of genes involved in the regulation of apoptosis and cell cycle after incubation with gefitinib. Among them, an upregulation of the growth arrest and DNA damage-inducible gene GADD153 was observed. Phosphorylation of ERK1/2, which inhibits GADD153 expression, was reduced in a time-dependent manner. However, no gefitinib-induced activation of the GADD153-inducing p38 mitogen-activated protein kinase was detected. Our data demonstrate that the inhibition of EGFR-TK by gefitinib induces growth inhibition, apoptosis and cell-cycle arrest in NE gastrointestinal tumour cells. Thus, EGFR-TK inhibition appears to be a promising novel approach for the treatment of NE tumour disease.
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Affiliation(s)
- M Höpfner
- Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, University Hospital Benjamin Franklin, Free University of Berlin, Hindenburgdamm 30, 12200 Berlin, Germany
| | - A P Sutter
- Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, University Hospital Benjamin Franklin, Free University of Berlin, Hindenburgdamm 30, 12200 Berlin, Germany
| | - B Gerst
- Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, University Hospital Benjamin Franklin, Free University of Berlin, Hindenburgdamm 30, 12200 Berlin, Germany
| | - M Zeitz
- Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, University Hospital Benjamin Franklin, Free University of Berlin, Hindenburgdamm 30, 12200 Berlin, Germany
| | - H Scherübl
- Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, University Hospital Benjamin Franklin, Free University of Berlin, Hindenburgdamm 30, 12200 Berlin, Germany
- Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, University Hospital Benjamin Franklin, Free University of Berlin, Hindenburgdamm 30, 12200 Berlin, Germany. E-mail:
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Jackson TA, Koterwas DM, Morgan MA, Bradford AP. Fibroblast growth factors regulate prolactin transcription via an atypical Rac-dependent signaling pathway. Mol Endocrinol 2003; 17:1921-30. [PMID: 12843210 DOI: 10.1210/me.2003-0167] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Fibroblast growth factors (FGFs) play a critical role in pituitary development and in pituitary tumor formation and progression. We have previously characterized FGF signal transduction and regulation of the tissue-specific rat prolactin (rPRL) promoter in GH4 pituitary cells. FGF induction of rPRL transcription is independent of Ras, but mediated by a protein kinase C-delta (PKCdelta)-dependent activation of MAPK (ERK). Here we demonstrate a functional role for the Rho family monomeric G protein, Rac1, in FGF regulation of PRL gene expression via an atypical signaling pathway. Expression of dominant negative Rac, but not RhoA or Cdc42, selectively inhibited FGF-induced rPRL promoter activity. Moreover, expression of dominant negative Rac also attenuated FGF-2 and FGF-4 stimulation of MAPK (ERK). However, in contrast to other Rac-dependent signaling pathways, FGF activation of rPRL promoter activity was independent of the c-Jun N-terminal kinase (JNK) and phosphoinositide 3-kinase/Akt cascades. FGFs failed to activate JNK1 or JNK2, and expression of dominant negative JNK or Akt constructs did not block FGF-induced PRL transcription. Consistent with the role of PKCdelta in FGF regulation of PRL gene expression, activation of the rPRL promoter was blocked by an inhibitor of phospholipase Cgamma (PLCgamma) activity. FGF treatment also induced rapid tyrosine phosphorylation of PLCgamma in a Rac-dependent manner. These results suggest that FGF-2 and FGF-4 activate PRL gene expression via a novel Rac1, PLCgamma, PKCdelta, and ERK cascade, independent of phosphoinositol-3-kinase and JNK.
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Affiliation(s)
- Twila A Jackson
- Section of Basic Reproductive Science, Department of Obstetrics & Gynecology, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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Mohammad HP, Abbud RA, Parlow AF, Lewin JS, Nilson JH. Targeted overexpression of luteinizing hormone causes ovary-dependent functional adenomas restricted to cells of the Pit-1 lineage. Endocrinology 2003; 144:4626-36. [PMID: 12960102 DOI: 10.1210/en.2003-0357] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The majority of pituitary adenomas in humans are nonmetastasizing, monoclonal neoplasms that occur in approximately 20% of the general population. Their development has been linked to a combination of extrinsic factors and intrinsic defects. We now demonstrate with transgenic mice that targeted and chronic overexpression of LH causes ovarian hyperstimulation and subsequent hyperproliferation of Pit-1-positive cells that culminates in the appearance of functional pituitary adenomas ranging from focal to multifocal expansion of lactotropes, somatotropes, and thyrotropes. Tumors fail to develop in ovariectomized mice, indicating that contributions from the ovary are necessary for adenoma development. Although the link between chronic ovarian hyperstimulation and PRL-secreting adenomas was expected, the involvement of somatotropes and thyrotropes was surprising and suggests that multiple ovarian hormones may contribute to this unusual pathological consequence. In support of this idea, we have found that ovariectomy followed by estrogen replacement results in the expansion of lactotropes selectively in LH overexpressing mice, but not somatotropes and thyrotropes. Collectively, these data indicate that estrogen is sufficient for the formation of lactotrope adenomas only in animals with a hyperstimulated ovary, whereas the appearance of GH- and TSH-secreting adenomas depends on multiple ovarian hormones. Together, our data expand current models of pituitary tumorigenesis by suggesting that chronic ovarian hyperstimulation may underlie the formation of a subset of pituitary adenomas containing lactotropes, somatotropes, and thyrotropes.
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Affiliation(s)
- Helai P Mohammad
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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40
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Kola B, Korbonits M, Diaz-Cano S, Kaltsas G, Morris DG, Jordan S, Metherell L, Powell M, Czirják S, Arnaldi G, Bustin S, Boscaro M, Mantero F, Grossman AB. Reduced expression of the growth hormone and type 1 insulin-like growth factor receptors in human somatotroph tumours and an analysis of possible mutations of the growth hormone receptor. Clin Endocrinol (Oxf) 2003; 59:328-38. [PMID: 12919156 DOI: 10.1046/j.1365-2265.2003.01851.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Clinical acromegaly is characterized by elevated GH secretion in the presence of high circulating IGF-I levels. We hypothesized that the physiological IGF-I/GH negative feedback loop may be reset in somatotroph adenomas, specifically in terms of the level of expression of these receptors or mutations of the GH receptor (GH-R) in such tumours. METHODS We therefore investigated the full coding sequence of the GH-R in a series of somatotroph and other pituitary adenomas. We also investigated the mRNA expression of these putative feedback receptors in a series of pituitary adenomas and normal pituitary tissue, and their protein expression by immunostaining. Real-time RT-PCR assay was used for the quantification of the type 1 IGF receptor (IGF-R) and GH receptor (GH-R) mRNA, and sequence analysis was performed on the coding region of the GH-R gene. RESULTS No somatic mutations of the GH-R mRNA were detected in 18 GH-secreting tumours or two nonfunctioning pituitary adenomas (NFPAs). However, the levels of GH-R mRNA were significantly lower in both somatotroph tumours and NFPAs compared to the normal pituitary (P < 0.05 for both). Immunostaining for GH-R also showed significantly less GH-R expression in somatotroph adenomas compared to normal pituitary tissue (P < 0.0001). IGF-R mRNA levels were significantly lower in somatotroph tumours compared to normal pituitary (P = 0.005), and trended lower in corticotroph tumours (P = 0.07), while the other tumour types showed no significant difference from normal pituitary. Immunostaining for IGF-R also showed less IGF-R protein in the somatotroph adenomas compared to the normal pituitary tissue (P < 0.01). CONCLUSIONS Our findings suggest that decreased feedback inhibition of GH because of somatic mutations of the coding region of the GH-R are unlikely to be a common factor in the pathogenesis of these tumours. Nevertheless, decreased expression of the GH-R and of IGF-R in somatotroph tumours (both at the mRNA and protein level) may, at least in part, help explain the continuous secretion of GH from the tumour despite the high circulating levels of IGF-I and GH.
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Affiliation(s)
- Blerina Kola
- Departments of Endocrinology and Histopatholgy, St Bartholomew's Hospital and National Institute of Neurology and Neurosurgery, London, UK.
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Itoh J, Serizawa A, Kawai K, Ishii Y, Teramoto A, Osamura RY. Vascular networks and endothelial cells in the rat experimental pituitary glands and in the human pituitary adenomas. Microsc Res Tech 2003; 60:231-5. [PMID: 12539177 DOI: 10.1002/jemt.10261] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
There has been considerable interest in the relationship between hormone-secreting endocrine cells (HSEC) and their microvessels (MVN) in human pituitary gland. However, microcirculatory networks have rarely been studied in three dimensions (3D). Therefore, this study was designed to visualize and to reveal the relationship between hormone secreting endocrine cells and their microvessel environment including vascular endothelial cells in 3D using rat pituitary glands under various experimental conditions by confocal laser scanning microscopy (CLSM). By CLSM, the 3D distributions of MVN were visualized and revealed a relationship between HSEC and MVN in experimental pituitary glands and human pituitary adenomas. Therefore, 3D reconstructed imaging by CLSM is a useful technique with which to investigate the microvessel environment of hormone-secreting cells and has the potential to reveal dynamic hormone-secreting pathways.
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Affiliation(s)
- Johbu Itoh
- Laboratories for Structure and Function Research, Tokai University School of Medicine, Tokai University School of Medicine, Kanagawa, 259-1193 Japan.
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Affiliation(s)
- Sylvia L Asa
- Department of Pathology and Laboratory Medicine, University of Toronto, University Health Network and Toronto Medical Laboratories, 610 University Avenue, Toronto, Ontario, Canada M5G 2M5.
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Abstract
Fibroblast growth factor receptors (FGFRs) have been implicated in a multitude of activities. Signaling of the 23 members of the FGF family is mediated through FGFR1-4. We show that FGF-19, which selectively binds FGFR4, can induce prolactin (PRL) but not growth hormone expression. FGF-19 also stimulated MAPK activation, an effect that was abrogated by a soluble dominant negative (dn) form of FGFR4. The response of the pituitary PRL promoter to FGF maps to an Ets-Pit1 binding site. We have previously shown that the hematopoietic zinc finger-containing transcription factor Ikaros (Ik) regulates FGFR4 as part of an overlapping site with that for an Ets-type factor in the FGFR4 promoter. Thus, we examined whether FGF-19 might regulate its own receptor through the Ets-Ik element in the FGFR4 promoter. Ets stimulated and dn-Ets inhibited basal FGFR4 and PRL promoter activity. In contrast, Ets enhanced FGF-19-induced PRL activation but failed to confer an effect for FGF-19 on the FGFR4 promoter. We conclude that FGFR4 mediates FGF-19 signaling to the PRL promoter. Our data also suggest a possible functional role for Ik in sorting Ets signals to the FGFR4 promoter, as distinct from the PRL promoter, where Ets partners with Pit1.
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Affiliation(s)
- Shunjiang Yu
- Department of Medicine, Mount Sinai Hospital and University of Toronto, Toronto, Ontario, Canada
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Abstract
Fibroblast growth factor receptors (FGFRs) have been implicated in a multitude of endocrine cell hormonal and proliferative properties, and FGFR4 is differentially expressed in normal and neoplastic pituitary. We therefore examined the functionally important cis-DNA elements and multiprotein complexes implicated in the cooperative control of expression of the human FGFR4 gene in pituitary cells. Using deletional mapping, we defined a 214-bp (-115/+99) promoter that was functional in pituitary GH4 and PRL 235 cells. Overlapping 40- to 50-bp fragments of this minimal promoter were examined by EMSA. Interestingly, fragment C (-64/-26) included potential binding sites for the hematopoietic zinc finger-containing transcription factor Ikaros (Ik) flanked by binding sites for Sp and Ets-type factors. DNA binding by Ik, Sp, and Ets-like factors was confirmed by oligonucleotide competition and supershifting with specific antibodies. Transcriptional regulation of FGFR4 by Ik was demonstrated by cotransfection of Ik1 with or without Sp1 or Ets overexpression and by disruption of the Ik binding site. Although both Ets-1 and Sp1 overexpression stimulated promoter activity, mutation of the Ik-binding site completely eliminated the Ik1 effect. Specific Ik expression was identified by Western blotting of pituitary GH4 and PRL235 cells and localized in primary mouse hormone-producing anterior pituitary cells by immunocytochemistry. Our findings point to a new role for Ik outside the hematopoietic system and suggest a novel transcriptional contribution with Ets and Sp1 in regulation of FGFR4 in the pituitary.
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Affiliation(s)
- ShunJiang Yu
- Department of Medicine, Mount Sinai Hospital and University of Toronto, Toronto, Ontario, Canada M5G 2M9
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Abstract
Over the past few years, significant contributions have been made to the understanding, diagnosis, and treatment of pituitary tumors. This article reviews recent advances in the areas of biology, diagnostic imaging, medical diagnosis and treatment, surgical results and technique, and adjuvant therapy in the form of radiotherapy and radiosurgery. Of particular note are the roles of endoscopy, intraoperative magnetic resonance imaging, radiosurgery, and radiation for nonfunction tumors, the diagnosis of Cushing's disease, the management of "incidentalomas," and new medication therapies.
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Affiliation(s)
- Paul L Penar
- Division of Neurosurgery, University of Vermont College of Medicine, Fletcher Allen Health Care-MCHV campus, 507 Fletcher House, 111 Colchester Avenue, Burlington, VT 05401, USA.
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