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Satou M, Wang J, Nakano-Tateno T, Teramachi M, Aoki S, Sugimoto H, Chik C, Tateno T. Autophagy inhibition suppresses hormone production and cell growth in pituitary tumor cells: A potential approach to pituitary tumors. Mol Cell Endocrinol 2024; 586:112196. [PMID: 38462123 DOI: 10.1016/j.mce.2024.112196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 03/12/2024]
Abstract
Pituitary tumors (PTs) represent about 10% of all intracranial tumors, and most are benign. However, some PTs exhibit continued growth despite multimodal therapies. Although temozolomide (TMZ), an alkylating chemotherapeutic agent, is a first-line medical treatment for aggressive PTs, some PTs are resistant to TMZ. Existing literature indicated the involvement of autophagy in cell growth in several types of tumors, including PTs, and autophagy inhibitors have anti-tumor effects. In this study, the expression of several autophagy-inducible genes, including Atg3, Beclin1, Map1lc3A, Map1lc3b, Ulk1, Wipi2, and Tfe3 in two PT cell lines, the mouse corticotroph AtT-20 cells and the rat mammosomatotroph GH4 cells were identified. Down regulation of Tfe3, a master switch of basal autophagy, using RNA interference, suppressed cell proliferation in AtT-20 cells, suggesting basal autophagy contributes to the maintenance of cellular functions in PT cells. Expectedly, treatment with bafilomycin A1, an autophagy inhibitor, suppressed cell proliferation, increased the cleavage of PARP1, and reduced ACTH production in AtT-20 cells. Treatment with two additional autophagy inhibitors, chloroquine (CQ) and monensin, demonstrated similar effects on cell proliferation, apoptosis, and ACTH production in AtT-20 cells. Also, treatment with CQ suppressed cell proliferation and growth hormone production in GH4 cells. Moreover, the combination of CQ and TMZ had an additive effect on the inhibition of cell proliferation in AtT-20 and GH4 cells. The additive effect of anti-cancer drugs such as CQ alone or in combination with TMZ may represent a novel therapeutic approach for PTs, in particular tumors with resistance to TMZ.
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Affiliation(s)
- Motoyasu Satou
- Division of Endocrinology and Metabolism, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada; Department of Biochemistry, Dokkyo Medical University School of Medicine, Mibu, Tochigi, Japan
| | - Jason Wang
- Division of Endocrinology and Metabolism, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Tae Nakano-Tateno
- Division of Endocrinology and Metabolism, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Mariko Teramachi
- Division of Endocrinology and Metabolism, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Shigeki Aoki
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Hiroyuki Sugimoto
- Department of Biochemistry, Dokkyo Medical University School of Medicine, Mibu, Tochigi, Japan
| | - Constance Chik
- Division of Endocrinology and Metabolism, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Toru Tateno
- Division of Endocrinology and Metabolism, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
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Demarchi G, Valla S, Perrone S, Chimento A, Bonadeo N, Vitale DL, Spinelli FM, Cervio A, Sevlever G, Alaniz L, Berner S, Cristina C. β-Catenin is reduced in membranes of human prolactinoma cells and it is inhibited by temozolomide in prolactin secreting tumor models. Tumour Biol 2022; 44:85-105. [DOI: 10.3233/tub-211500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
INTRODUCTION: Prolactinomas are the most frequent pituitary tumor subtype. Despite most of them respond to medical treatment, a proportion are resistant and become a challenge in clinical management. Wnt/β-Catenin pathway has been implicated in several cancers including pituitary tumors and other sellar region malignancies. Interestingly, Wnt/β-Catenin inhibition augments the cytotoxicity of the chemotherapeutic agent Temozolomide (TMZ) in different cancers. TMZ is now being implemented as rescue therapy for aggressive pituitary adenoma treatment. However, the molecular mechanisms associated with TMZ action in pituitary tumors remain unclear. OBJECTIVES: Our aims in the present study were to evaluate differential β-Catenin expression in human resistant prolactinomas and Wnt/β-Catenin signaling activation and involvement in Prolactin (PRL) secreting experimental models treated with TMZ. RESULTS: We first evaluated by immunohistochemistry β-Catenin localization in human resistant prolactinomas in which we demonstrated reduced membrane β-Catenin in prolactinoma cells compared to normal pituitaries, independently of the Ki-67 proliferation indexes. In turn, in vivo 15 mg/kg of orally administered TMZ markedly reduced PRL production and increased prolactinoma cell apoptosis in mice bearing xenografted prolactinomas. Intratumoral β-Catenin strongly correlated with Prl and Cyclin D1, and importantly, TMZ downregulated both β-Catenin and Cyclin D1, supporting their significance in prolactinoma growth and as candidates of therapeutic targets. When tested in vitro, TMZ directly reduced MMQ cell viability, increased apoptosis and produced G2/M cell cycle arrest. Remarkably, β-Catenin activation and VEGF secretion were inhibited by TMZ in vitro. CONCLUSIONS: We concluded that dopamine resistant prolactinomas undergo a β-Catenin relocalization in relation to normal pituitaries and that TMZ restrains experimental prolactinoma tumorigenicity by reducing PRL production and β-Catenin activation. Together, our findings contribute to the understanding of Wnt/β-Catenin implication in prolactinoma maintenance and TMZ therapy, opening the opportunity of new treatment strategies for aggressive and resistant pituitary tumors.
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Affiliation(s)
- Gianina Demarchi
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Sofía Valla
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Sofía Perrone
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Agustina Chimento
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Nadia Bonadeo
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Daiana Luján Vitale
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Fiorella Mercedes Spinelli
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Andrés Cervio
- Departamento de Neurocirugía/Departamento de Neuropatología, Instituto FLENI, Buenos Aires, Argentina
| | - Gustavo Sevlever
- Departamento de Neurocirugía/Departamento de Neuropatología, Instituto FLENI, Buenos Aires, Argentina
| | - Laura Alaniz
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
| | - Silvia Berner
- Servicio de Neurocirugía, Clínica Santa Isabel, Buenos Aires, Argentina
| | - Carolina Cristina
- Centro de Investigaciones Básicas y Aplicadas, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Buenos Aires, Argentina
- Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) – UNNOBA-UNSAdA-CONICET, Pergamino, Buenos Aires, Argentina
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Gesmundo I, Granato G, Fuentes-Fayos AC, Alvarez CV, Dieguez C, Zatelli MC, Congiusta N, Banfi D, Prencipe N, Leone S, Brunetti L, Castaño JP, Luque RM, Cai R, Sha W, Ghigo E, Schally AV, Granata R. Antagonists of Growth Hormone-Releasing Hormone Inhibit the Growth of Pituitary Adenoma Cells by Hampering Oncogenic Pathways and Promoting Apoptotic Signaling. Cancers (Basel) 2021; 13:cancers13163950. [PMID: 34439107 PMCID: PMC8393969 DOI: 10.3390/cancers13163950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/26/2021] [Accepted: 08/03/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Many studies have demonstrated that the antagonists of growth hormone-releasing hormone (GHRH) exert inhibitory activities in a variety of experimental cancers; however, their potential antitumor role in pituitary adenomas (PAs) remains largely unknown. Here, we show that GHRH antagonists of Miami (MIA) class, MIA-602 and MIA-690, are able to reduce the growth and promote cell death in hormone-secreting PA cell lines, through the inhibition of mechanisms implicated in tumorigenesis and cancer progression. MIA-602 and MIA-690 also decreased the viability of tumor cells derived from human pituitary tumors. Overall, these findings suggest that GHRH antagonists may represent new therapeutic tools for the treatment of PAs, both alone or in combination with standard pharmacological treatments. Abstract Pituitary adenomas (PAs) are intracranial tumors, often associated with excessive hormonal secretion and severe comorbidities. Some patients are resistant to medical therapies; therefore, novel treatment options are needed. Antagonists of growth hormone-releasing hormone (GHRH) exert potent anticancer effects, and early GHRH antagonists were found to inhibit GHRH-induced secretion of pituitary GH in vitro and in vivo. However, the antitumor role of GHRH antagonists in PAs is largely unknown. Here, we show that the GHRH antagonists of MIAMI class, MIA-602 and MIA-690, inhibited cell viability and growth and promoted apoptosis in GH/prolactin-secreting GH3 PA cells transfected with human GHRH receptor (GH3-GHRHR), and in adrenocorticotropic hormone ACTH-secreting AtT20 PA cells. GHRH antagonists also reduced the expression of proteins involved in tumorigenesis and cancer progression, upregulated proapoptotic molecules, and lowered GHRH receptor levels. The combination of MIA-690 with temozolomide synergistically blunted the viability of GH3-GHRHR and AtT20 cells. Moreover, MIA-690 reduced both basal and GHRH-induced secretion of GH and intracellular cAMP levels. Finally, GHRH antagonists inhibited cell viability in human primary GH- and ACTH-PA cell cultures. Overall, our results suggest that GHRH antagonists, either alone or in combination with pharmacological treatments, may be considered for further development as therapy for PAs.
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Affiliation(s)
- Iacopo Gesmundo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
| | - Giuseppina Granato
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
| | - Antonio C. Fuentes-Fayos
- Maimonides Institute for Biomedical Research of Córdoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Córdoba and Reina Sofia University Hospital, 14004 Córdoba, Spain; (A.C.F.-F.); (J.P.C.); (R.M.L.)
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 28029 Madrid, Spain
| | - Clara V. Alvarez
- Centro de Investigaciones Médicas (CIMUS) e Instituto de Investigaciones Sanitarias, University of Santiago de Compostela and Complexo Hospitalario Universitario of Santiago de Compostela, 14004 Santiago de Compostela, Spain; (C.V.A.); (C.D.)
| | - Carlos Dieguez
- Centro de Investigaciones Médicas (CIMUS) e Instituto de Investigaciones Sanitarias, University of Santiago de Compostela and Complexo Hospitalario Universitario of Santiago de Compostela, 14004 Santiago de Compostela, Spain; (C.V.A.); (C.D.)
| | - Maria Chiara Zatelli
- Section of Endocrinology and Internal Medicine, Department of Medical Sciences, University of Ferrara, 15706 Ferrara, Italy;
| | - Noemi Congiusta
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
| | - Dana Banfi
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
| | - Nunzia Prencipe
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
| | - Sheila Leone
- Department of Pharmacy, G. d’Annunzio University of Chieti-Pescara, 66100 Chieti, Italy; (S.L.); (L.B.)
| | - Luigi Brunetti
- Department of Pharmacy, G. d’Annunzio University of Chieti-Pescara, 66100 Chieti, Italy; (S.L.); (L.B.)
| | - Justo P. Castaño
- Maimonides Institute for Biomedical Research of Córdoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Córdoba and Reina Sofia University Hospital, 14004 Córdoba, Spain; (A.C.F.-F.); (J.P.C.); (R.M.L.)
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 28029 Madrid, Spain
| | - Raúl M. Luque
- Maimonides Institute for Biomedical Research of Córdoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Córdoba and Reina Sofia University Hospital, 14004 Córdoba, Spain; (A.C.F.-F.); (J.P.C.); (R.M.L.)
- CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 28029 Madrid, Spain
| | - Renzhi Cai
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (R.C.); (W.S.); (A.V.S.)
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center, Miami, FL 33125, USA
| | - Wei Sha
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (R.C.); (W.S.); (A.V.S.)
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center, Miami, FL 33125, USA
| | - Ezio Ghigo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
| | - Andrew V. Schally
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; (R.C.); (W.S.); (A.V.S.)
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center, Miami, FL 33125, USA
- Comprehensive Cancer Center, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Division of Hematology/Oncology, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Department of Pathology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Riccarda Granata
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, 10126 Turin, Italy; (I.G.); (G.G.); (N.C.); (D.B.); (N.P.); (E.G.)
- Correspondence:
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Liu J, He Y, Zhang X, Yan X, Huang Y. Clinicopathological analysis of 250 cases of pituitary adenoma under the new WHO classification. Oncol Lett 2020; 19:1890-1898. [PMID: 32194684 PMCID: PMC7039149 DOI: 10.3892/ol.2020.11263] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 11/13/2019] [Indexed: 01/01/2023] Open
Abstract
Pituitary adenomas (PAs) are a common subtype of intracranial tumors. The aim of the present study was to analyse the clinical and pathological features of different types of pituitary adenomas (PAs) according to the 2017 World Health Organisation Endocrine Organ Tumor Classification guidelines. The clinical data of 250 patients with PAs were collected and analysed. Differences in the incidence of invasion, recurrence and apoplexy in patients between high- and low-risk PAs were compared, as were differences in the Ki-67 index between invasive and non-invasive PAs and between recurrent PAs and non-recurrent PAs. Of the 250 cases, 45 cases were diagnosed as somatotroph adenomas, 26 cases as lactotroph adenomas, 1 case as thyrotroph adenoma, 61 cases as corticotroph adenomas, 93 cases as gonadotropin adenomas, 15 cases as null cell adenomas and 9 cases as plurihormonal adenomas. There were 5 types of high-risk pituitary adenoma identified: 17 cases of sparsely granulated somatotroph adenoma, 11 cases of lactotroph adenoma in men, 3 cases of plurihormonal PIT-1 positive adenoma and 42 cases of silent corticotroph adenoma. Crooke's cell adenoma was not identified. High-risk PAs had significantly higher rates of invasion, recurrence and apoplexy compared with that in low-risk types (P<0.001). Invasive PAs had a significantly higher Ki-67 index compared with that in non-invasive PAs (3.5±1.8 vs. 2.8±1.3; P<0.01). Recurrent PAs had a significantly higher Ki-67 index compared with that in non-recurrent PAs (3.9±1.9 vs. 2.8±1.3; P<0.001). According to the 2017 classification criteria, patients most frequently had gonadotrophin cell adenomas, followed by corticotroph adenomas and the proportion of null cell adenomas was reduced. Differences were noted in the proliferation, recurrence and apoplexy characteristics of high-risk PAs and low-risk PAs. The invasion and recurrence of PAs were found to be related to the Ki-67 index.
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Affiliation(s)
- Jiayu Liu
- Department of Neurosurgery, Tianjin Huanhu Hospital, Tianjin 300000, P.R. China.,Department of Neurosurgery, Peking University People's Hospital, Beijing 100044, P.R. China
| | - Yuhao He
- Department of Neurosurgery, Third People's Hospital of Chengdu, Chengdu, Sichuan 610000, P.R. China
| | - Xuebin Zhang
- Department of Pathology, Tianjin Huanhu Hospital, Tianjin 300000, P.R. China
| | - Xiaoling Yan
- Department of Pathology, Tianjin Huanhu Hospital, Tianjin 300000, P.R. China
| | - Ying Huang
- Department of Neurosurgery, Tianjin Huanhu Hospital, Tianjin 300000, P.R. China
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Chen C, Yin S, Zhang S, Wang M, Hu Y, Zhou P, Jiang S. Treatment of aggressive prolactinoma with temozolomide: A case report and review of literature up to date. Medicine (Baltimore) 2017; 96:e8733. [PMID: 29381964 PMCID: PMC5708963 DOI: 10.1097/md.0000000000008733] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
RATIONALE Aggressive pituitary adenomas and pituitary carcinomas are rare and demand multiple treatment strategies. Temozolomide, an orally active alkylating chemotherapeutic agent, has recently been recommended as a salvage medication for refractory pituitary adenomas or carcinomas. PATIENT CONCERNS A 17-year-old male presenting with aggressive prolactinoma that continued to progress despite surgery, gamma knife, and dopamine agonists. DIAGNOSES The diagnosis of refractory aggressive prolactinoma was made on the basis of clinical findings and the lack of efficacy of conventional treatment. INTERVENTIONS The patient received the most frequently recommended regimen of temozolomide treatment for 22 cycles. OUTCOMES Temozolomide resulted in a remarkable shrinkage of tumor mass and inhibition of prolactin secretion and this patient's clinical condition improved progressively. LESSONS Temozolomide can be used as a salvage treatment to refractory pituitary tumors and o(6)-methylguanine-DNA methyltransferase (MGMT) status is a significant predictor to the effectiveness of temozolomide based on the existing literature.
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Affiliation(s)
- Cheng Chen
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province
| | - Senlin Yin
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province
| | - Shizhen Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong Province, China
| | - Mengmeng Wang
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province
| | - Yu Hu
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province
| | - Peizhi Zhou
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province
| | - Shu Jiang
- Department of Neurosurgery, West China Hospital of Sichuan University, Chengdu, Sichuan Province
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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: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [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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Ferone D, Pivonello C, Vitale G, Zatelli MC, Colao A, Pivonello R. Molecular basis of pharmacological therapy in Cushing's disease. Endocrine 2014; 46:181-98. [PMID: 24272603 DOI: 10.1007/s12020-013-0098-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 10/19/2013] [Indexed: 01/16/2023]
Abstract
Cushing's disease (CD) is a severe endocrine condition caused by an adrenocorticotropin (ACTH)-producing pituitary adenoma that chronically stimulates adrenocortical cortisol production and with potentially serious complications if not or inadequately treated. Active CD may produce a fourfold increase in mortality and is associated with significant morbidities. Moreover, excess mortality risk may persist even after CD treatment. Although predictors of risk in treated CD are not fully understood, the importance of early recognition and adequate treatment is well established. Surgery with resection of a pituitary adenoma is still the first line therapy, being successful in about 60-70 % of patients; however, recurrence within 2-4 years may often occur. When surgery fails, medical treatment can reduce cortisol production and ameliorate clinical manifestations while more definitive therapy becomes effective. Compounds that target hypothalamic-pituitary axis, glucocorticoid synthesis or adrenocortical function are currently used to control the deleterious effects of chronic glucocorticoid excess. In this review we describe and analyze the molecular basis of the drugs targeting the disease at central level, suppressing ACTH secretion, as well as at peripheral level, acting as adrenal inhibitors, or glucocorticoid receptor antagonists. Understanding of the underlying molecular mechanisms in CD and of glucocorticoid biology should promote the development of new targeted and more successful therapies in the future. Indeed, most of the drugs discussed have been tested in limited clinical trials, but there is potential therapeutic benefit in compounds with better specificity for the class of receptors expressed by ACTH-secreting tumors. However, long-term follow-up with management of persistent comorbidities is needed even after successful treatment of CD.
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Affiliation(s)
- Diego Ferone
- Endocrinology, Department of Internal Medicine and Medical Specialties & Center of Excellence for Biomedical Research, IRCCS AOU San Martino-IST, University of Genova, Viale Benedetto XV, 6, 16132, Genoa, Italy,
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Dai C, Zhang B, Liu X, Guo K, Ma S, Cai F, Yang Y, Yao Y, Feng M, Bao X, Deng K, Jiao Y, Wei Z, Junji W, Xing B, Lian W, Wang R. Pyrimethamine sensitizes pituitary adenomas cells to temozolomide through cathepsin B-dependent and caspase-dependent apoptotic pathways. Int J Cancer 2013; 133:1982-93. [PMID: 23564480 DOI: 10.1002/ijc.28199] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 03/19/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Congxin Dai
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Bo Zhang
- Department of Neurosurgery; The First Affiliated Hospital of Dalian Medical University; Dalian; Liaoning; People's Republic of China
| | - Xiaohai Liu
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Kai Guo
- Department of Neurosurgery; The First Affiliated Hospital of Dalian Medical University; Dalian; Liaoning; People's Republic of China
| | - Sihai Ma
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Feng Cai
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Yakun Yang
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Yong Yao
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Ming Feng
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Xinjie Bao
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Kan Deng
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Yonghui Jiao
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Zhenqing Wei
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Wei Junji
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Bing Xing
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Wei Lian
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
| | - Renzhi Wang
- Department of Neurosurgery; Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing; People's Republic of China
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Batisse M, Raverot G, Maqdasy S, Durando X, Sturm N, Montoriol PF, Kemeny JL, Chazal J, Trouillas J, Tauveron I. Aggressive silent GH pituitary tumor resistant to multiple treatments, including temozolomide. Cancer Invest 2013; 31:190-6. [PMID: 23477586 DOI: 10.3109/07357907.2013.775293] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Temozolomide (TMZ) has been proposed as a therapeutic option in aggressive pituitary tumors. Among the published cases, GH expressing tumors were rare. We describe a patient with initially benign silent GH adenoma that transformed into an aggressive GH secreting tumor resistant to usual therapy. MGMT expression was high and the MGMT promoter was unmethylated. Before this aggressive course, patient received three cycles of TMZ; no response was observed. Four cases of GH aggressive tumor treated by TMZ have been reported. Response to TMZ was observed in one of these four patients. Predictive factors of failure of TMZ remain unclear.
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Affiliation(s)
- Marie Batisse
- Department Endocrinologie, CHU Clermont-Ferrand, Clermont-Ferrand, France.
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10
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Dai C, Zhang B, Liu X, Ma S, Yang Y, Yao Y, Feng M, Bao X, Li G, Wang J, Guo K, Ma W, Xing B, Lian W, Xiao J, Cai F, Zhang H, Wang R. Inhibition of PI3K/AKT/mTOR pathway enhances temozolomide-induced cytotoxicity in pituitary adenoma cell lines in vitro and xenografted pituitary adenoma in female nude mice. Endocrinology 2013; 154:1247-59. [PMID: 23384836 DOI: 10.1210/en.2012-1908] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Invasive pituitary adenomas (PAs) are often refractory to standard therapy and salvage treatment with temozolomide (TMZ). Hyperactivation of the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway contributes to chemotherapy resistance in many cancers. XL765, a novel dual-PI3K/mTOR inhibitor, has recently shown its efficacy as a monotherapy and in combination with conventional therapeutics in many cancers. The hyperactive PI3K/AKT/mTOR pathway frequently occurs in invasive PAs. In this study, we investigated whether XL765 sensitizes PA cells to TMZ in vitro and in vivo. Experiments were carried out to evaluate the effect of XL765 and TMZ alone or in combination on cell proliferation and apoptosis of PA cell lines (αT3-1, GH3, and MMQ) in vitro as well as the tumor growth and serum GH and prolactin secretions in a GH3 xenograft tumor model of female nude mice. XL765 and TMZ synergistically inhibited the growth of PA cell lines and induced apoptosis. Combination of XL765 and TMZ synergistically inhibited tumor growth, decreased serum GH and prolactin levels, and reduced the sacrifice rate of GH3 xenograft tumor models without increased systemic side effects. In addition, XL765 in combination with TMZ dramatically decreased phosphorylation of AKT and mTOR as well as the expression of Bcl-2. The increased expression of cleaved poly (ADP-ribose) polymerase and Bcl-2-associated X protein along with elevated caspase-3/7 activity were also observed in the combination group. Therefore, dual inhibitors of PI3K and mTOR may enhance alkylating agent-mediated cytotoxicity and provide a novel regimen in the treatment of invasive PAs.
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Affiliation(s)
- Congxin Dai
- Department of Neurosurgery, Peking Union Medical College Hospital, Beijing 100730, China
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11
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Oh MC, Kunwar S, Blevins L, Aghi MK. Medical Versus Surgical Management of Prolactinomas. Neurosurg Clin N Am 2012; 23:669-78. [DOI: 10.1016/j.nec.2012.06.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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McCormack AI, Wass JAH, Grossman AB. Aggressive pituitary tumours: the role of temozolomide and the assessment of MGMT status. Eur J Clin Invest 2011; 41:1133-48. [PMID: 21496012 DOI: 10.1111/j.1365-2362.2011.02520.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Aggressive pituitary tumours are associated with substantial morbidity and mortality. Treatment options are often limited, and chemotherapy has been reserved as salvage therapy although historically results have often been disappointing. However, temozolomide, an oral alkylating agent, has recently demonstrated significant activity against these tumours. A DNA repair protein, 06-methylguanine-DNA methyltransferase (MGMT) has been suggested as a biomarker to predict response to temozolomide in pituitary tumours. MATERIALS AND METHODS This paper will review the current literature on temozolomide and pituitary tumours and discuss the recent controversy surrounding the value of determining the MGMT status in this tumour group. A PubMed search was performed to retrieve articles, using the terms 'pituitary tumour' and 'temozolomide'. RESULTS Overall, 24/40 (60%) of the published cases demonstrated a response to temozolomide therapy. The highest response rates were seen amongst prolactinomas (73%) and ACTH-secreting tumours (60%), whilst nonfunctioning pituitary tumours exhibit lower response rates (40%). Responsivity is typically evident in the first 3 months of therapy and may be dramatic and sustained. Low MGMT expression, as determined by immunohistochemistry, is associated with a high response rate (76%), whilst high MGMT expression has not been associated with responses. MGMT promoter methylation does not correlate with temozolomide response. CONCLUSIONS Temozolomide is the first chemotherapeutic agent to show substantial response rates in aggressive pituitary tumours. MGMT immunohistochemistry, but not MGMT methylation analysis, shows promise as a predictive tool. Prospective clinical trials are now necessary to more accurately determine the efficacy of this agent in this patient group.
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Affiliation(s)
- Ann I McCormack
- Cancer Genetics Unit, Hormones and Cancer Group, Kolling Institute of Medical Research, Royal North Shore Hospital, Sydney, NSW, Australia
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Zuhur SS, Tanik C, Karaman Ö, Velet S, Çil E, Öztürk FY, Özkayalar H, Müslüman AM, Altuntaş Y. MGMT immunoexpression in growth hormone-secreting pituitary adenomas and its correlation with Ki-67 labeling index and cytokeratin distribution pattern. Endocrine 2011; 40:222-7. [PMID: 21792693 DOI: 10.1007/s12020-011-9485-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 04/28/2011] [Indexed: 10/18/2022]
Abstract
Recent publications suggest the utility of temozolomide (TMZ) in the management of aggressive pituitary adenomas and carcinomas, resistant to conventional treatments. The response to TMZ is inversely correlated with tumoral expression of O-6 methylguanine DNA methyl transferase (MGMT). Therefore, we aimed to assess MGMT immunoexpression in pure GH-secreting pituitary adenomas, in an effort to predict the likelihood of response to TMZ, and to correlate MGMT immunoexpression with Ki-67 LI and cytokeratin (CK) distribution pattern. Our material consisted of 36 GH-secreting pituitary adenomas (21 female,15 male, mean age 42.5±10.5), operated at our center between 2003 and 2010. Immunostaining for MGMT, Ki-67, and CK was performed using avidin-biotin-peroxidase complex method. Immunoreactivity for MGMT and Ki-67 was evaluated microscopically and recorded as percentages of positive nuclear immunostaining. CK distribution pattern was also evaluated microscopically and assoreted into dot-like and nondot-like pattern subtypes. MGMT immunoexpression scored as 0=none, 1=<10%, 2=<25%, 3=<50%, and 4=>50%. Staining for MGMT was <10% (score 1) in 30 (83.3%), 10-25% (score 2) in 3 (8.3%), 25-50% (score 3) in 2 (5.6%) and >50% (score 4) in 1 (2.8%) of the tumors, respectively. There was no correlation between Ki-67 LI and CK distribution pattern with MGMT immunoreactivity (P>0.05). Data from the current study suggest a large proportion of GH-secreting adenomas, including those with dot-like CK distribution pattern and high Ki-67 LI, demonstrate negative/low MGMT immunoreactivity and could be treated with TMZ, if conventional treatment fails.
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Affiliation(s)
- Sayid Shafi Zuhur
- Endocrinology and Metabolism Clinic, Sisli Etfal Training and Research Hospital, 34377 Sisli, Istanbul, Turkey.
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15
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Hueng DY, Ma HI, Sytwu HK, Liu MY. Letter to the Editor: Temozolomide and pituitary adenoma. J Neurosurg 2011; 114:1820: author reply 1820-1. [DOI: 10.3171/2011.3.jns11361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Dueng-Yuan Hueng
- Tri-Service General Hospital, Taipei, Taiwan; and
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Hsin-I Ma
- Tri-Service General Hospital, Taipei, Taiwan; and
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Huey-Kang Sytwu
- Tri-Service General Hospital, Taipei, Taiwan; and
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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Abstract
Prolactinomas are the most common hormonally active pituitary tumors and are usually successfully treated with dopamine agonists. A small proportion, however, appears not to respond to such treatment and such cases are termed resistant prolactinomas. Resistance is generally defined as failure to achieve normoprolactinemia and inability to induce tumor shrinkage. Reduced dopamine receptor density on lactotroph cells is currently considered the major underlying mechanism of resistance. Treatment options in resistant cases usually include substitution with another dopamine agonist, increasing the dose of the drug, as well as surgery, radiotherapy, and experimental medical therapies.
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Affiliation(s)
- V Vasilev
- Department of Endocrinology, Centre Hospitalier Universitaire de Liège, University of Liège, Belgium
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17
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Salehi F, Scheithauer BW, Kros JM, Lau Q, Fealey M, Erickson D, Kovacs K, Horvath E, Lloyd RV. MGMT promoter methylation and immunoexpression in aggressive pituitary adenomas and carcinomas. J Neurooncol 2011; 104:647-57. [DOI: 10.1007/s11060-011-0532-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 01/31/2011] [Indexed: 01/08/2023]
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