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Ryu GR, Bae D, Uddin S, Meah MS, Ahmad W, Silvano KJ, Ahn G, Cha JY, Lee E, Song KH, Kim WY, Kim MG. Effect of transcription factor MEOX on insulin gene expression in glucagon-like peptide 1-secreting cells. In Vitro Cell Dev Biol Anim 2024:10.1007/s11626-024-00964-6. [PMID: 39138833 DOI: 10.1007/s11626-024-00964-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Accepted: 07/31/2024] [Indexed: 08/15/2024]
Abstract
Currently, the supply of beta cells for islet transplantation in the treatment of type 1 diabetes is limited. Enteroendocrine cells (EECs) are believed to have high potential as stem cells because they share significant developmental similarities with beta cells. In a previous study, we derived EEC cells that secrete individual gut hormones from STC-1 cells. This study aimed to examine intestinal hormone secretion and expression, investigate the expression of developmental-related transcription factors, and analyze the effect of MEOX on insulin gene expression in isolated EECs. The expression and secretion of enteroendocrine hormones were evaluated in L6 and K34 cells from STC-1 cells. Expression patterns of beta cell- and development-related genes in L6 and K34 cells were compared with beta cells. Comparisons of the MEOX-induced expression of Ins in beta cells and GLP-1-secreting cells were investigated. Both L6 and K34 cells predominantly expressed Glp1 and Gip, respectively. The secretion pattern of GLP-1 in L6 cells was similar to that of GLUTag cells. Previous microarray analysis confirmed MEOX as developmentally relevant transcription factors expressed in beta cells. Overexpression of MEOX showed a tendency to increase Ins expression in L6 and GLUTag cells, but not in MIN6 cells. However, when PDX1 and MEOX were co-expressed in GLUTag cells, insulin expression was suppressed, similar to that observed in MIN6 cells. These findings suggest a potential role for MEOX in regulating the expression of the Ins gene in both beta cells and GLP-1-secreting cells. Further studies are warranted to elucidate the underlying mechanism.
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Affiliation(s)
- Gyeong Ryul Ryu
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Dongryeoul Bae
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Shahab Uddin
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
- Division of Applied Life Science (BK21 Four), Institute of Agricultural and Life Science, Plant Molecular Biology and Biotechnology Research Center, Plant Biological Rhythm Research Center, Research Institute of Life Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Mohammed Sohel Meah
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Waqas Ahmad
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Kris John Silvano
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Gyeongik Ahn
- Division of Applied Life Science (BK21 Four), Institute of Agricultural and Life Science, Plant Molecular Biology and Biotechnology Research Center, Plant Biological Rhythm Research Center, Research Institute of Life Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Joon-Yung Cha
- Division of Applied Life Science (BK21 Four), Institute of Agricultural and Life Science, Plant Molecular Biology and Biotechnology Research Center, Plant Biological Rhythm Research Center, Research Institute of Life Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Esder Lee
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Ki-Ho Song
- Division of Endocrinology & Metabolism, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Woe-Yeon Kim
- Division of Applied Life Science (BK21 Four), Institute of Agricultural and Life Science, Plant Molecular Biology and Biotechnology Research Center, Plant Biological Rhythm Research Center, Research Institute of Life Science, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Min Gab Kim
- College of Pharmacy and Research Institute of Pharmaceutical Science, Gyeongsang National University, Jinju, 52828, Republic of Korea.
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Pavlou AM, Papachristou E, Bonovolias I, Anagnostou E, Anastasiadou P, Poulopoulos A, Bakopoulou A, Andreadis D. Pancreatic Differentiation of Oral Minor Salivary Gland Stem Cells. Stem Cell Rev Rep 2024:10.1007/s12015-024-10757-9. [PMID: 38967770 DOI: 10.1007/s12015-024-10757-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/25/2024] [Indexed: 07/06/2024]
Abstract
INTRODUCTION Stem cells from various sources including major salivary glands have been used to establish pancreatic differentiation in an attempt to provide new treatment options for patients with diabetes mellitus. In contrast, the potential of using the more easily accessible intraoral minor salivary glands has not been evaluated so far. MATERIALS AND METHODS Salivary stem cells were isolated from normal labial minor salivary glands that were removed during the excision of a mucocele and were attempted to differentiate into pancreatic cell lines using a culture medium enriched with activin A, retinoic acid and GLP-1.Real time RT-PCR was used to evaluate the expression of the genes of pancreatic transcription factors MafA, Ptf1a, Hb9 and Arx. Complementary, 22 labial minor salivary gland paraffin-embedded specimens were examined using immunohistochemistry for the presence of the relevant gene products of the pancreatic transcription factors Arx, MafA, Ptf1a and Pdx1. RESULTS The differentiated salivary stem cells(cells of passage 3) expressed the genes of the pancreatic transcription factors MafA, Ptf1a, Hb9 and Arx even on the first day of the experiment while immunohistochemistry also confirmed the presence of the protein products of Arx, MafA, Ptf1a as well as Pdx1[> 50% of the specimens for Arx(5/8) and MafA(7/8), < 50% for Ptf1a(5/11) and Pdx1(5/11)] in ducts, mesenchymal connective tissue and acinar cells. CONCLUSIONS Labial minor salivary glands may share gene and protein characteristics with pancreas suggesting a possible usefulness for pancreatic regeneration or substitution in cases of deficiency.
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Affiliation(s)
- Achilleia-Maria Pavlou
- Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
| | - Eleni Papachristou
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Ioannis Bonovolias
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Eleftherios Anagnostou
- Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Pinelopi Anastasiadou
- Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Athanasios Poulopoulos
- Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Athina Bakopoulou
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | - Dimitrios Andreadis
- Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
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Liu T, Li R, Sun L, Xu Z, Wang S, Zhou J, Wu X, Shi K. Menin orchestrates hepatic glucose and fatty acid uptake via deploying the cellular translocation of SIRT1 and PPARγ. Cell Biosci 2023; 13:175. [PMID: 37740216 PMCID: PMC10517496 DOI: 10.1186/s13578-023-01119-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 08/30/2023] [Indexed: 09/24/2023] Open
Abstract
BACKGROUND Menin is a scaffold protein encoded by the Men1 gene, which interacts with various transcriptional proteins to activate or repress cellular processes and is a key mediator in multiple organs. Both liver-specific and hepatocyte-specific Menin deficiency promotes high-fat diet-induced liver steatosis in mice, as well as insulin resistance and type 2 diabetic phenotype. The potential link between Menin and hepatic metabolism homeostasis may provide new insights into the mechanism of fatty liver disease. RESULTS Disturbance of hepatic Menin expression impacts metabolic pathways associated with non-alcoholic fatty liver disease (NAFLD), including the FoxO signaling pathway, which is similar to that observed in both oleic acid-induced fatty hepatocytes model and biopsied fatty liver tissues, but with elevated hepatic Menin expression and inhibited FABP1. Higher levels of Menin facilitate glucose uptake while restraining fatty acid uptake. Menin targets the expression of FABP3/4/5 and also CD36 or GK, PCK by binding to their promoter regions, while recruiting and deploying the cellular localization of PPARγ and SIRT1 in the nucleus and cytoplasm. Accordingly, Menin binds to PPARγ and/or FoxO1 in hepatocytes, and orchestrates hepatic glucose and fatty acid uptake by recruiting SIRT1. CONCLUSION Menin plays an orchestration role as a transcriptional activator and/or repressor to target downstream gene expression levels involved in hepatic energy uptake by interacting with the cellular energy sensor SIRT1, PPARγ, and/or FoxO1 and deploying their translocations between the cytoplasm and nucleus, thereby maintaining metabolic homeostasis. These findings provide more evidence suggesting Menin could be targeted for the treatment of hepatic steatosis, NAFLD or metabolic dysfunction-associated fatty liver disease (MAFLD), and even other hepatic diseases.
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Affiliation(s)
- Tingjun Liu
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
- Key Laboratory of Animal Bioengineering and Disease Prevention of Shandong Province, Taian, 271018, Shandong, People's Republic of China
| | - Ranran Li
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
| | - Lili Sun
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
| | - Zhongjin Xu
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
| | - Shengxuan Wang
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
| | - Jingxuan Zhou
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
- Key Laboratory of Animal Bioengineering and Disease Prevention of Shandong Province, Taian, 271018, Shandong, People's Republic of China
| | - Xuanning Wu
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China
- Key Laboratory of Animal Bioengineering and Disease Prevention of Shandong Province, Taian, 271018, Shandong, People's Republic of China
| | - Kerong Shi
- Laboratory of Animal Stem Cell and Reprogramming, College of Animal Science and Technology, Shandong Agricultural University, No. 61 Daizong Street, Taian, 271018, Shandong, People's Republic of China.
- Key Laboratory of Animal Bioengineering and Disease Prevention of Shandong Province, Taian, 271018, Shandong, People's Republic of China.
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Jha S, Simonds WF. Molecular and Clinical Spectrum of Primary Hyperparathyroidism. Endocr Rev 2023; 44:779-818. [PMID: 36961765 PMCID: PMC10502601 DOI: 10.1210/endrev/bnad009] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 02/09/2023] [Accepted: 03/17/2023] [Indexed: 03/25/2023]
Abstract
Recent data suggest an increase in the overall incidence of parathyroid disorders, with primary hyperparathyroidism (PHPT) being the most prevalent parathyroid disorder. PHPT is associated with morbidities (fractures, kidney stones, chronic kidney disease) and increased risk of death. The symptoms of PHPT can be nonspecific, potentially delaying the diagnosis. Approximately 15% of patients with PHPT have an underlying heritable form of PHPT that may be associated with extraparathyroidal manifestations, requiring active surveillance for these manifestations as seen in multiple endocrine neoplasia type 1 and 2A. Genetic testing for heritable forms should be offered to patients with multiglandular disease, recurrent PHPT, young onset PHPT (age ≤40 years), and those with a family history of parathyroid tumors. However, the underlying genetic cause for the majority of patients with heritable forms of PHPT remains unknown. Distinction between sporadic and heritable forms of PHPT is useful in surgical planning for parathyroidectomy and has implications for the family. The genes currently known to be associated with heritable forms of PHPT account for approximately half of sporadic parathyroid tumors. But the genetic cause in approximately half of the sporadic parathyroid tumors remains unknown. Furthermore, there is no systemic therapy for parathyroid carcinoma, a rare but potentially fatal cause of PHPT. Improved understanding of the molecular characteristics of parathyroid tumors will allow us to identify biomarkers for diagnosis and novel targets for therapy.
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Affiliation(s)
- Smita Jha
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1752, USA
| | - William F Simonds
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1752, USA
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Sadeghimahalli F, Karbaschi R, Salimi M, Khodagholi F, Zardooz H. Pancreatic HB9 protein level is affected by early life stress in young adult rats: possible involvement of TNF-α and corticosterone. Arch Physiol Biochem 2021; 127:406-413. [PMID: 31368362 DOI: 10.1080/13813455.2019.1645699] [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: 02/27/2019] [Revised: 06/25/2019] [Accepted: 07/15/2019] [Indexed: 01/06/2023]
Abstract
This study examined foot shock stress effects, during weaning, on pancreatic HB9 protein expression in young adult male rats in the presence or absence of adulthood stress. The pups were divided into Control, Early life stress, Young adult stress, and Early + young adult stress groups. Plasma corticosterone, insulin, glucose, and TNF-α concentrations, and pancreatic HB9 protein expression were assessed. At 2 weeks of age, stress increased plasma corticosterone level. During young adulthood, plasma TNF-α and glucose concentrations increased, whereas plasma insulin and pancreatic HB9 protein levels decreased in Early life stress group. Whereas, Early + young adulthood stress group showed no change in the study parameters, except for plasma corticosterone and insulin concentrations. Overall, early life stress reduced pancreatic HB9 protein expression possibly by elevating plasma corticosterone and TNF-α levels in early life and adulthood, respectively. However, combined with adulthood stress, HB9 protein expression increased to the level of Control.
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Affiliation(s)
- Forouzan Sadeghimahalli
- Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Education Development Center, Mazandaran University of Medical Sciences, Sari, Iran
| | - Roxana Karbaschi
- Faculty of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mina Salimi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fariba Khodagholi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- NeuroBiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Homeira Zardooz
- Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Ozyerli‐Goknar E, Nizamuddin S, Timmers HTM. A Box of Chemistry to Inhibit the MEN1 Tumor Suppressor Gene Promoting Leukemia. ChemMedChem 2021; 16:1391-1402. [PMID: 33534953 PMCID: PMC8252030 DOI: 10.1002/cmdc.202000972] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Indexed: 12/30/2022]
Abstract
Targeting protein-protein interactions (PPIs) with small-molecule inhibitors has become a hotbed of modern drug development. In this review, we describe a new class of PPI inhibitors that block menin from binding to MLL proteins. Menin is encoded by the MEN1 tumor suppressor, but acts as an essential cofactor for MLL/KMT2A-rearranged leukemias. The most promising menin-MLL inhibitors belong to the thienopyrimidine class and have recently entered phase I/II clinical trials for treating acute leukemias characterized by MLL/KMT2A translocations or NPM1 mutations. As single agents, thienopyrimidine compounds eradicate leukemia in a xenograft models of primary leukemic cells belonging to the MLL-rearranged or NPM1-mutant subtypes. These compounds are well tolerated with few or no side effects, which is remarkable given the tumor-suppressor function of menin. The menin-MLL inhibitors highlight how leukemia patients could benefit from a targeted epigenetic therapy with novel PPI inhibitors obtained by directed chemical evolution.
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Affiliation(s)
- Ezgi Ozyerli‐Goknar
- German Cancer Consortium (DKTK) partner site Freiburg German Cancer Research Center (DKFZ) Medical Center-University of Freiburg, Department of UrologyBreisacherstrasse 6679016FreiburgGermany
| | - Sheikh Nizamuddin
- German Cancer Consortium (DKTK) partner site Freiburg German Cancer Research Center (DKFZ) Medical Center-University of Freiburg, Department of UrologyBreisacherstrasse 6679016FreiburgGermany
| | - H. T. Marc Timmers
- German Cancer Consortium (DKTK) partner site Freiburg German Cancer Research Center (DKFZ) Medical Center-University of Freiburg, Department of UrologyBreisacherstrasse 6679016FreiburgGermany
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Brandi ML, Agarwal SK, Perrier ND, Lines KE, Valk GD, Thakker RV. Multiple Endocrine Neoplasia Type 1: Latest Insights. Endocr Rev 2021; 42:133-170. [PMID: 33249439 PMCID: PMC7958143 DOI: 10.1210/endrev/bnaa031] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Indexed: 02/06/2023]
Abstract
Multiple endocrine neoplasia type 1 (MEN1), a rare tumor syndrome that is inherited in an autosomal dominant pattern, is continuing to raise great interest for endocrinology, gastroenterology, surgery, radiology, genetics, and molecular biology specialists. There have been 2 major clinical practice guidance papers published in the past 2 decades, with the most recent published 8 years ago. Since then, several new insights on the basic biology and clinical features of MEN1 have appeared in the literature, and those data are discussed in this review. The genetic and molecular interactions of the MEN1-encoded protein menin with transcription factors and chromatin-modifying proteins in cell signaling pathways mediated by transforming growth factor β/bone morphogenetic protein, a few nuclear receptors, Wnt/β-catenin, and Hedgehog, and preclinical studies in mouse models have facilitated the understanding of the pathogenesis of MEN1-associated tumors and potential pharmacological interventions. The advancements in genetic diagnosis have offered a chance to recognize MEN1-related conditions in germline MEN1 mutation-negative patients. There is rapidly accumulating knowledge about clinical presentation in children, adolescents, and pregnancy that is translatable into the management of these very fragile patients. The discoveries about the genetic and molecular signatures of sporadic neuroendocrine tumors support the development of clinical trials with novel targeted therapies, along with advancements in diagnostic tools and surgical approaches. Finally, quality of life studies in patients affected by MEN1 and related conditions represent an effort necessary to develop a pharmacoeconomic interpretation of the problem. Because advances are being made both broadly and in focused areas, this timely review presents and discusses those studies collectively.
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Affiliation(s)
| | | | - Nancy D Perrier
- The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Gerlof D Valk
- University Medical Center Utrecht, CX Utrecht, the Netherlands
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Nelakurti DD, Pappula AL, Rajasekaran S, Miles WO, Petreaca RC. Comprehensive Analysis of MEN1 Mutations and Their Role in Cancer. Cancers (Basel) 2020; 12:cancers12092616. [PMID: 32937789 PMCID: PMC7565326 DOI: 10.3390/cancers12092616] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/04/2020] [Accepted: 09/10/2020] [Indexed: 12/24/2022] Open
Abstract
Simple Summary Cancers are characterized by accumulation of genetic mutations in key cell cycle regulators that alter or disable the function of these genes. Such mutations can be inherited or arise spontaneously during the life of the individual. The MEN1 gene prevents uncontrolled cell division and it is considered a tumor suppressor. Inherited MEN1 mutations are associated with certain parathyroid and pancreatic syndromes while spontaneous mutations have been detected in cancer cells. We investigated whether inherited mutations appear in cancer cells which would suggest that patients with parathyroid and pancreatic syndromes have a predisposition to develop cancer. We find a weak correlation between the spectrum of inherited mutations and those appearing spontaneously. Thus, inherited MEN1 mutations may not be a good predictor of tumorigenesis. Abstract MENIN is a scaffold protein encoded by the MEN1 gene that functions in multiple biological processes, including cell proliferation, migration, gene expression, and DNA damage repair. MEN1 is a tumor suppressor gene, and mutations that disrupts MEN1 function are common to many tumor types. Mutations within MEN1 may also be inherited (germline). Many of these inherited mutations are associated with a number of pathogenic syndromes of the parathyroid and pancreas, and some also predispose patients to hyperplasia. In this study, we cataloged the reported germline mutations from the ClinVar database and compared them with the somatic mutations detected in cancers from the Catalogue of Somatic Mutations in Cancer (COSMIC) database. We then used statistical software to determine the probability of mutations being pathogenic or driver. Our data show that many confirmed germline mutations do not appear in tumor samples. Thus, most mutations that disable MEN1 function in tumors are somatic in nature. Furthermore, of the germline mutations that do appear in tumors, only a fraction has the potential to be pathogenic or driver mutations.
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Affiliation(s)
- Devi D. Nelakurti
- Biomedical Science Undergraduate Program, The Ohio State University Medical School, Columbus, OH 43210, USA;
| | - Amrit L. Pappula
- Computer Science and Engineering Undergraduate Program, The Ohio State University, Columbus, OH 43210, USA;
| | - Swetha Rajasekaran
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA;
| | - Wayne O. Miles
- Department of Cancer Biology and Genetics, The Ohio State University Medical School, Columbus, OH 43210, USA;
| | - Ruben C. Petreaca
- Department of Molecular Genetics, The Ohio State University, Marion, OH 43302, USA
- Correspondence:
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Wild-type menin is rapidly degraded via the ubiquitin-proteasome pathway in a rat insulinoma cell line. Biosci Rep 2019; 39:220725. [PMID: 31652443 PMCID: PMC6822493 DOI: 10.1042/bsr20190471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 09/18/2019] [Accepted: 10/02/2019] [Indexed: 11/17/2022] Open
Abstract
Menin is encoded by multiple endocrine neoplasia type 1 (MEN1) gene, the germ line mutations of which are the main cause of pancreatic neuroendocrine tumors (PNETs). To date, a large number of frameshift, nonsense and missense mutations of MEN1 have been identified to be responsible for part of MEN1-defficient PNETs patients due to truncation or rapid degradation of menin protein. However, the stability of the wild-type (WT) menin in PNETs is totally unknown. In the present study, we observed ubiquitination of WT menin in 293T cells by transfection of ectopic WT menin and HA-ubiquitin. As expected, either endogenous or ectopic WT menin is stable in 293T cells, whereas in INS-1 cells, a rat insulinoma cell line derived from PNETs, either endogenous or ectopic WT menin is rapidly degraded through ubiquitin-proteasome pathway. Furthermore, the degradation of WT menin is more rapid in the presence of serum. Our findings suggest that in part of PNETs patients with WT MEN1, a ubiquitin-proteasome system targeting menin is untimely activated.
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Goliusova DV, Klementieva NV, Mokrysheva NG, Kiselev SL. Molecular Mechanisms of Carcinogenesis Associated with MEN1 Gene Mutation. RUSS J GENET+ 2019. [DOI: 10.1134/s1022795419080052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Kharade SS, Parekh VI, Agarwal SK. Functional Defects From Endocrine Disease-Associated Mutations in HLXB9 and Its Interacting Partner, NONO. Endocrinology 2018; 159:1199-1212. [PMID: 29309627 PMCID: PMC5793795 DOI: 10.1210/en.2017-03155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/28/2017] [Indexed: 12/31/2022]
Abstract
The insulin-secreting pancreatic neuroendocrine tumors, insulinomas, characterized by increased pancreatic islet β-cell proliferation, express the phosphorylated isoform of the β-cell differentiation factor HLXB9 that interacts with NONO/p54NRB, a survival factor. Interestingly, two different homozygous germline mutations in HLXB9, p.F248L and p.F272L, were reported in neonatal diabetes, a condition with functional β-cell deficiency. Also, two somatic heterozygous NONO mutations were found in endocrine-related tumors, p.H146R (parathyroid) and p.R293H (small intestine neuroendocrine tumor). However, the biological consequence of the mutations, and the role of HLXB9-NONO interaction in normal or abnormal β cells, is not known. Expression, localization, and functional analysis of the clinically relevant HLXB9 and NONO mutants showed that HLXB9/p.F248L mutant localized in the nucleus but lacked phosphorylation, and NONO/p.R293H mutant was structurally impaired. The HLXB9 and NONO mutants retained the ability to interact, and overexpression of wild-type or mutant HXLB9 in MIN6 cells suppressed cell proliferation. To further understand the biological consequence of the HLXB9-NONO interaction, we mapped the NONO-interacting region in HLXB9. An 80-amino acid conserved region of HLXB9 could compete with full-length HLXB9 to interact with NONO; however, in functional assays, nuclear expression of this HLXB9-conserved region in MIN6 cells did not interfere with cell proliferation. Overall, our results highlight the importance of HLXB9 in conditions of β-cell excess (insulinomas) and in conditions of β-cell loss or dysfunction (diabetes). Our studies implicate therapeutic strategies for either reducing β-cell proliferation in insulinomas or alleviating normal β-cell deficiency in diabetes through the modulation of HLXB9 phosphorylation.
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Affiliation(s)
- Sampada S. Kharade
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Vaishali I. Parekh
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Sunita K. Agarwal
- Metabolic Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Shi K, Liu X, Li H, Lin X, Yan Z, Cao Q, Zhao M, Xu Z, Wang Z. Menin Modulates Mammary Epithelial Cell Numbers in Bovine Mammary Glands Through Cyclin D1. J Mammary Gland Biol Neoplasia 2017; 22:221-233. [PMID: 29188494 PMCID: PMC5854757 DOI: 10.1007/s10911-017-9385-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 11/13/2017] [Indexed: 11/27/2022] Open
Abstract
Menin, the protein encoded by the MEN1 gene, is abundantly expressed in the epithelial cells of mammary glands. Here, we found MEN1/menin expression slowly decreased with advancing lactation but increased by the end of lactation. It happened that the number of bovine mammary epithelial cells decreases since lactation, suggesting a role of menin in the control of mammary epithelial cell growth. Indeed, reduction of menin expression through MEN1-specific siRNA transfection in the bovine mammary epithelial cells caused cell growth arrest in G1/S phase. Decreased mRNA and protein expression of Cyclin D1 was observed upon MEN1 knockdown. Furthermore, menin was confirmed to physically bind to the promoter region of Cyclin D1 through a ChIP assay, indicating that menin plays a regulatory role in mammary epithelial cell cycle progression. Moreover, lower expression of MEN1/menin induced increased epithelial cell apoptosis and caused extracellular matrix remodeling by down-regulating its associated genes, such as DSG2 and KRT5, suggesting that menin's role may also be involved in the control of cell-cell adhesion in normal mammary glands. Taken together, our data revealed an unknown molecular function of menin in epithelial cell proliferation, which may be important in the regulation of lactation behavior of mammary glands.
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Affiliation(s)
- Kerong Shi
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China.
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China.
| | - Xue Liu
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Honghui Li
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Xueyan Lin
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Zhengui Yan
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Qiaoqiao Cao
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Meng Zhao
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Zhongjin Xu
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China
| | - Zhonghua Wang
- College of Animal Science and Technology, Shandong Agricultural University, Taian, 271018, China.
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, Taian, 271018, China.
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Long Noncoding RNA MEG3 Is an Epigenetic Determinant of Oncogenic Signaling in Functional Pancreatic Neuroendocrine Tumor Cells. Mol Cell Biol 2017; 37:MCB.00278-17. [PMID: 28847847 DOI: 10.1128/mcb.00278-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/22/2017] [Indexed: 12/26/2022] Open
Abstract
The long noncoding RNA (lncRNA) MEG3 is significantly downregulated in pancreatic neuroendocrine tumors (PNETs). MEG3 loss corresponds with aberrant upregulation of the oncogenic hepatocyte growth factor (HGF) receptor c-MET in PNETs. Meg3 overexpression in a mouse insulin-secreting PNET cell line, MIN6, downregulates c-Met expression. However, the molecular mechanism by which MEG3 regulates c-MET is not known. Using chromatin isolation by RNA purification and sequencing (ChIRP-Seq), we identified Meg3 binding to unique genomic regions in and around the c-Met gene. In the absence of Meg3, these c-Met regions displayed distinctive enhancer-signature histone modifications. Furthermore, Meg3 relied on functional enhancer of zeste homolog 2 (EZH2), a component of polycomb repressive complex 2 (PRC2), to inhibit c-Met expression. Another mechanism of lncRNA-mediated regulation of gene expression utilized triplex-forming GA-GT rich sequences. Transfection of such motifs from Meg3 RNA, termed triplex-forming oligonucleotides (TFOs), in MIN6 cells suppressed c-Met expression and enhanced cell proliferation, perhaps by modulating other targets. This study comprehensively establishes epigenetic mechanisms underlying Meg3 control of c-Met and the oncogenic consequences of Meg3 loss or c-Met gain. These findings have clinical relevance for targeting c-MET in PNETs. There is also the potential for pancreatic islet β-cell expansion through c-MET regulation to ameliorate β-cell loss in diabetes.
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14
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Dreijerink KMA, Timmers HTM, Brown M. Twenty years of menin: emerging opportunities for restoration of transcriptional regulation in MEN1. Endocr Relat Cancer 2017; 24:T135-T145. [PMID: 28811299 PMCID: PMC5609455 DOI: 10.1530/erc-17-0281] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 08/14/2017] [Indexed: 12/11/2022]
Abstract
Since the discovery of the multiple endocrine neoplasia type 1 (MEN1) gene in 1997, elucidation of the molecular function of its protein product, menin, has been a challenge. Biochemical, proteomics, genetics and genomics approaches have identified various potential roles, which converge on gene expression regulation. The most consistent findings show that menin connects transcription factors and chromatin-modifying enzymes, in particular, the histone H3K4 methyltransferase complexes MLL1 and MLL2. Chromatin immunoprecipitation combined with next-generation sequencing has enabled studying genome-wide dynamics of chromatin binding by menin. We propose that menin regulates cell type-specific transcriptional programs by linking chromatin regulatory complexes to specific transcription factors. In this fashion, the MEN1 gene is a tumor suppressor gene in the endocrine tissues that are affected in MEN1. Recent studies have hinted at possibilities to pharmacologically restore the epigenetic changes caused by loss of menin function as therapeutic strategies for MEN1, for example, by inhibition of histone demethylases. The current lack of appropriate cellular model systems for MEN1-associated tumors is a limitation for compound testing, which needs to be addressed in the near future. In this review, we look back at the past twenty years of research on menin and the mechanism of disease of MEN1. In addition, we discuss how the current understanding of the molecular function of menin offers future directions to develop novel treatments for MEN1-associated endocrine tumors.
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Affiliation(s)
- Koen M A Dreijerink
- Department of EndocrinologyVU University Medical Center, Amsterdam, The Netherlands
| | - H T Marc Timmers
- German Cancer Consortium (DKTK) partner site FreiburgGerman Cancer Research Center (DKFZ) and Department of Urology, Medical Center-University of Freiburg, Freiburg, Germany
| | - Myles Brown
- Department of Medical OncologyDana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
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15
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Agarwal SK. The future: genetics advances in MEN1 therapeutic approaches and management strategies. Endocr Relat Cancer 2017; 24:T119-T134. [PMID: 28899949 PMCID: PMC5679100 DOI: 10.1530/erc-17-0199] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 08/08/2017] [Indexed: 02/01/2023]
Abstract
The identification of the multiple endocrine neoplasia type 1 (MEN1) gene in 1997 has shown that germline heterozygous mutations in the MEN1 gene located on chromosome 11q13 predisposes to the development of tumors in the MEN1 syndrome. Tumor development occurs upon loss of the remaining normal copy of the MEN1 gene in MEN1-target tissues. Therefore, MEN1 is a classic tumor suppressor gene in the context of MEN1. This tumor suppressor role of the protein encoded by the MEN1 gene, menin, holds true in mouse models with germline heterozygous Men1 loss, wherein MEN1-associated tumors develop in adult mice after spontaneous loss of the remaining non-targeted copy of the Men1 gene. The availability of genetic testing for mutations in the MEN1 gene has become an essential part of the diagnosis and management of MEN1. Genetic testing is also helping to exclude mutation-negative cases in MEN1 families from the burden of lifelong clinical screening. In the past 20 years, efforts of various groups world-wide have been directed at mutation analysis, molecular genetic studies, mouse models, gene expression studies, epigenetic regulation analysis, biochemical studies and anti-tumor effects of candidate therapies in mouse models. This review will focus on the findings and advances from these studies to identify MEN1 germline and somatic mutations, the genetics of MEN1-related states, several protein partners of menin, the three-dimensional structure of menin and menin-dependent target genes. The ongoing impact of all these studies on disease prediction, management and outcomes will continue in the years to come.
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Affiliation(s)
- Sunita K Agarwal
- Metabolic Diseases BranchNational Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
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16
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Li H, Liu X, Wang Z, Lin X, Yan Z, Cao Q, Zhao M, Shi K. MEN1/Menin regulates milk protein synthesis through mTOR signaling in mammary epithelial cells. Sci Rep 2017; 7:5479. [PMID: 28710500 PMCID: PMC5511157 DOI: 10.1038/s41598-017-06054-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 06/07/2017] [Indexed: 01/17/2023] Open
Abstract
The MEN1 gene, which encodes the protein Menin, was investigated for its regulatory role in milk protein synthesis in mammary glands. Menin responds to nutrient and hormone levels via the PI3K/Akt/mTOR pathway. Bovine mammary epithelial cells and tissues were used as experimental models in this study. The results revealed that the milk protein synthesis capacity of mammary epithelial cells could be regulated by MEN1/Menin. The overexpression of Menin caused significant suppression of factors involved in the mTOR pathway, as well as milk protein κ-casein (CSNK). In contrast, a significant increase in these factors and CSNK was observed upon MEN1/Menin knockdown. The repression of MEN1/Menin on the mTOR pathway was also observed in mammary gland tissues. Additionally, MEN1/Menin was found to elicit a negative response on prolactin (PRL) and/or insulin (INS), which caused a similar downstream impact on mTOR pathway factors and milk proteins. Collectively, our data indicate that MEN1/Menin could play a regulatory role in milk protein synthesis through mTOR signaling in the mammary gland by mediating the effects of hormones and nutrient status. The discovery of Menin's role in mammary glands suggests Menin could be potential new target for the improvement of milk performance and adjustment of lactation period of dairy cows.
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Affiliation(s)
- Honghui Li
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Xue Liu
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Zhonghua Wang
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Xueyan Lin
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Zhengui Yan
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Qiaoqiao Cao
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Meng Zhao
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China
| | - Kerong Shi
- Shandong Key Laboratory of Animal Bioengineering and Disease Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong, 271018, P. R. China.
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17
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Ehrlich L, Hall C, Meng F, Lairmore T, Alpini G, Glaser S. A Review of the Scaffold Protein Menin and its Role in Hepatobiliary Pathology. Gene Expr 2017; 17:251-263. [PMID: 28485270 PMCID: PMC5765438 DOI: 10.3727/105221617x695744] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Multiple endocrine neoplasia type 1 (MEN1) is a familial cancer syndrome with neuroendocrine tumorigenesis of the parathyroid glands, pituitary gland, and pancreatic islet cells. The MEN1 gene codes for the canonical tumor suppressor protein, menin. Its protein structure has recently been crystallized, and it has been investigated in a multitude of other tissues. In this review, we summarize recent advancements in understanding the structure of the menin protein and its function as a scaffold protein in histone modification and epigenetic gene regulation. Furthermore, we explore its role in hepatobiliary autoimmune diseases, cancers, and metabolic diseases. In particular, we discuss how menin expression and function are regulated by extracellular signaling factors and nuclear receptor activation in various hepatic cell types. How the many signaling pathways and tissue types affect menin's diverse functions is not fully understood. We show that small-molecule inhibitors affecting menin function can shed light on menin's broad role in pathophysiology and elucidate distinct menin-dependent processes. This review reveals menin's often dichotomous function through analysis of its role in multiple disease processes and could potentially lead to novel small-molecule therapies in the treatment of cholangiocarcinoma or biliary autoimmune diseases.
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Affiliation(s)
- Laurent Ehrlich
- *Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA
| | - Chad Hall
- †Department of Surgery, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA
| | - Fanyin Meng
- *Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA
- ‡Research, Central Texas Veterans Health Care System, Temple, TX, USA
- §Baylor Scott & White Digestive Disease Research Center, Baylor Scott & White Health, Temple, TX, USA
| | - Terry Lairmore
- †Department of Surgery, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA
| | - Gianfranco Alpini
- *Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA
- ‡Research, Central Texas Veterans Health Care System, Temple, TX, USA
- §Baylor Scott & White Digestive Disease Research Center, Baylor Scott & White Health, Temple, TX, USA
| | - Shannon Glaser
- *Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA
- ‡Research, Central Texas Veterans Health Care System, Temple, TX, USA
- §Baylor Scott & White Digestive Disease Research Center, Baylor Scott & White Health, Temple, TX, USA
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18
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Bonnavion R, Teinturier R, Gherardi S, Leteurtre E, Yu R, Cordier-Bussat M, Du R, Pattou F, Vantyghem MC, Bertolino P, Lu J, Zhang CX. Foxa2, a novel protein partner of the tumour suppressor menin, is deregulated in mouse and human MEN1 glucagonomas. J Pathol 2017; 242:90-101. [PMID: 28188614 DOI: 10.1002/path.4885] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 01/17/2017] [Accepted: 01/30/2017] [Indexed: 11/10/2022]
Abstract
Foxa2, known as one of the pioneer factors, plays a crucial role in islet development and endocrine functions. Its expression and biological functions are regulated by various factors, including, in particular, insulin and glucagon. However, its expression and biological role in adult pancreatic α-cells remain elusive. In the current study, we showed that Foxa2 was overexpressed in islets from α-cell-specific Men1 mutant mice, at both the transcriptional level and the protein level. More importantly, immunostaining analyses showed its prominent nuclear accumulation, specifically in α-cells, at a very early stage after Men1 disruption. Similar nuclear FOXA2 expression was also detected in a substantial proportion (12/19) of human multiple endocrine neoplasia type 1 (MEN1) glucagonomas. Interestingly, our data revealed an interaction between Foxa2 and menin encoded by the Men1 gene. Furthermore, using several approaches, we demonstrated the relevance of this interaction in the regulation of two tested Foxa2 target genes, including the autoregulation of the Foxa2 promoter by Foxa2 itself. The current study establishes menin, a novel protein partner of Foxa2, as a regulator of Foxa2, the biological functions of which extend beyond the pancreatic endocrine cells. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Rémy Bonnavion
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France
| | - Romain Teinturier
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France
| | - Samuele Gherardi
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France
| | - Emmanuelle Leteurtre
- Institut de Pathologie, CHRU de Lille, Lille, France.,Department of Endocrinology and Metabolism, Univ. Lille 2, INSERM UMR 1190, Lille, France
| | - Run Yu
- Division of Endocrinology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Martine Cordier-Bussat
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France
| | - Rui Du
- The E-Institute of Shanghai, Sino-French Life Science and Genomic Centre, Ruijin Hospital, Shanghai, PR China.,Shanghai Clinical Centre for Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao-Tong University, Shanghai, PR China
| | - François Pattou
- Department of Endocrinology and Metabolism, Univ. Lille 2, INSERM UMR 1190, Lille, France.,CHRU Lille, Endocrine Surgery, Lille, France
| | - Marie-Christine Vantyghem
- Department of Endocrinology and Metabolism, Univ. Lille 2, INSERM UMR 1190, Lille, France.,CHRU Lille, Endocrinology, Lille, France
| | - Philippe Bertolino
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France
| | - Jieli Lu
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France.,The E-Institute of Shanghai, Sino-French Life Science and Genomic Centre, Ruijin Hospital, Shanghai, PR China.,Shanghai Clinical Centre for Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao-Tong University, Shanghai, PR China
| | - Chang Xian Zhang
- INSERM U1052, Lyon, France.,CNRS UMR5286, Lyon, France.,Université de Lyon, Lyon, France.,The E-Institute of Shanghai, Sino-French Life Science and Genomic Centre, Ruijin Hospital, Shanghai, PR China
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19
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Pan FC, Brissova M, Powers AC, Pfaff S, Wright CVE. Inactivating the permanent neonatal diabetes gene Mnx1 switches insulin-producing β-cells to a δ-like fate and reveals a facultative proliferative capacity in aged β-cells. Development 2016; 142:3637-48. [PMID: 26534984 DOI: 10.1242/dev.126011] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Homozygous Mnx1 mutation causes permanent neonatal diabetes in humans, but via unknown mechanisms. Our systematic and longitudinal analysis of Mnx1 function during murine pancreas organogenesis and into the adult uncovered novel stage-specific roles for Mnx1 in endocrine lineage allocation and β-cell fate maintenance. Inactivation in the endocrine-progenitor stage shows that Mnx1 promotes β-cell while suppressing δ-cell differentiation programs, and is crucial for postnatal β-cell fate maintenance. Inactivating Mnx1 in embryonic β-cells (Mnx1(Δbeta)) caused β-to-δ-like cell transdifferentiation, which was delayed until postnatal stages. In the latter context, β-cells escaping Mnx1 inactivation unexpectedly upregulated Mnx1 expression and underwent an age-independent persistent proliferation. Escaper β-cells restored, but then eventually surpassed, the normal pancreatic β-cell mass, leading to islet hyperplasia in aged mice. In vitro analysis of islets isolated from Mnx1(Δbeta) mice showed higher insulin secretory activity and greater insulin mRNA content than in wild-type islets. Mnx1(Δbeta) mice also showed a much faster return to euglycemia after β-cell ablation, suggesting that the new β-cells derived from the escaper population are functional. Our findings identify Mnx1 as an important factor in β-cell differentiation and proliferation, with the potential for targeting to increase the number of endogenous β-cells for diabetes therapy.
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Affiliation(s)
- Fong Cheng Pan
- Vanderbilt University Program in Developmental Biology, Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Marcela Brissova
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Alvin C Powers
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN 37232, USA VA Tennessee Valley Healthcare System, Nashville, TN 37212, USA
| | - Samuel Pfaff
- Gene Expression Laboratory, The Salk Institute, La Jolla, CA 92037, USA
| | - Christopher V E Wright
- Vanderbilt University Program in Developmental Biology, Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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20
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Desai SS, Kharade SS, Parekh VI, Iyer S, Agarwal SK. Pro-oncogenic Roles of HLXB9 Protein in Insulinoma Cells through Interaction with Nono Protein and Down-regulation of the c-Met Inhibitor Cblb (Casitas B-lineage Lymphoma b). J Biol Chem 2015; 290:25595-608. [PMID: 26342078 DOI: 10.1074/jbc.m115.661413] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Indexed: 12/21/2022] Open
Abstract
Pancreatic islet β-cells that lack the MEN1-encoded protein menin develop into tumors. Such tumors express the phosphorylated isoform of the β-cell differentiation transcription factor HLXB9. It is not known how phospho-HLXB9 acts as an oncogenic factor in insulin-secreting β-cell tumors (insulinomas). In this study we investigated the binding partners and target genes of phospho-HLXB9 in mouse insulinoma MIN6 β-cells. Co-immunoprecipitation coupled with mass spectrometry showed a significant association of phospho-HLXB9 with the survival factor p54nrb/Nono (54-kDa nuclear RNA-binding protein, non-POU-domain-containing octamer). Endogenous phospho-HLXB9 co-localized with endogenous Nono in the nucleus. Overexpression of HLXB9 decreased the level of overexpressed Nono but not endogenous Nono. Anti-phospho-HLXB9 chromatin immunoprecipitation followed by deep sequencing (ChIP-Seq) identified the c-Met inhibitor, Cblb, as a direct phospho-HLXB9 target gene. Phospho-HLXB9 occupied the promoter of Cblb and reduced the expression of Cblb mRNA. Cblb overexpression or HLXB9 knockdown decreased c-Met protein and reduced cell migration. Also, increased phospho-HLXB9 coincided with reduced Cblb and increased c-Met in insulinomas of two mouse models of menin loss. These data provide mechanistic insights into the role of phospho-HLXB9 as a pro-oncogenic factor by interacting with a survival factor and by promoting the oncogenic c-Met pathway. These mechanisms have therapeutic implications for reducing β-cell proliferation in insulinomas by inhibiting phospho-HLXB9 or its interaction with Nono and modulating the expression of its direct (Cblb) or indirect (c-Met) targets. Our data also implicate the use of pro-oncogenic activities of phospho-HLXB9 in β-cell expansion strategies to alleviate β-cell loss in diabetes.
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Affiliation(s)
- Shruti S Desai
- From the Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Sampada S Kharade
- From the Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Vaishali I Parekh
- From the Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Sucharitha Iyer
- From the Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | - Sunita K Agarwal
- From the Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
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21
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Modali SD, Parekh VI, Kebebew E, Agarwal SK. Epigenetic regulation of the lncRNA MEG3 and its target c-MET in pancreatic neuroendocrine tumors. Mol Endocrinol 2015; 29:224-37. [PMID: 25565142 DOI: 10.1210/me.2014-1304] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Biallelic inactivation of MEN1 encoding menin in pancreatic neuroendocrine tumors (PNETs) associated with the multiple endocrine neoplasia type 1 (MEN1) syndrome is well established, but how menin loss/inactivation initiates tumorigenesis is not well understood. We show that menin activates the long noncoding RNA maternally expressed gene 3 (Meg3) by histone-H3 lysine-4 trimethylation and CpG hypomethylation at the Meg3 promoter CRE site, to allow binding of the transcription factor cAMP response element-binding protein. We found that Meg3 has tumor-suppressor activity in PNET cells because the overexpression of Meg3 in MIN6 cells (insulin-secreting mouse PNET cell line) blocked cell proliferation and delayed cell cycle progression. Gene expression microarray analysis showed that Meg3 overexpression in MIN6 mouse insulinoma cells down-regulated the expression of the protooncogene c-Met (hepatocyte growth factor receptor), and these cells showed significantly reduced cell migration/invasion. Compared with normal islets, mouse or human MEN1-associated PNETs expressed less MEG3 and more c-MET. Therefore, a tumor-suppressor long noncoding RNA (MEG3) and suppressed protooncogene (c-MET) combination could elicit menin's tumor-suppressor activity. Interestingly, MEG3 and c-MET expression was also altered in human sporadic insulinomas (insulin secreting PNETs) with hypermethylation at the MEG3 promoter CRE-site coinciding with reduced MEG3 expression. These data provide insights into the β-cell proliferation mechanisms that could retain their functional status. Furthermore, in MIN6 mouse insulinoma cells, DNA-demethylating drugs blocked cell proliferation and activated Meg3 expression. Our data suggest that the epigenetic activation of lncRNA MEG3 and/or inactivation of c-MET could be therapeutic for treating PNETs and insulinomas.
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Affiliation(s)
- Sita D Modali
- Metabolic Diseases Branch (S.D.M., V.I.P., S.K.A.), National Institute of Diabetes and Digestive and Kidney Diseases, and Endocrine Oncology Branch (E.K.), National Cancer Institute, National Institutes of Health, Bethesda Maryland 20892
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22
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MicroRNA-142-3p, a novel target of tumor suppressor menin, inhibits osteosarcoma cell proliferation by down-regulation of FASN. Tumour Biol 2014; 35:10287-93. [DOI: 10.1007/s13277-014-2316-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 07/04/2014] [Indexed: 10/25/2022] Open
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23
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Pieterman CRC, Conemans EB, Dreijerink KMA, de Laat JM, Timmers HTM, Vriens MR, Valk GD. Thoracic and duodenopancreatic neuroendocrine tumors in multiple endocrine neoplasia type 1: natural history and function of menin in tumorigenesis. Endocr Relat Cancer 2014; 21:R121-42. [PMID: 24389729 DOI: 10.1530/erc-13-0482] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mutations of the multiple endocrine neoplasia type 1 (MEN1) gene lead to loss of function of its protein product menin. In keeping with its tumor suppressor function in endocrine tissues, the majority of the MEN1-related neuroendocrine tumors (NETs) show loss of heterozygosity (LOH) on chromosome 11q13. In sporadic NETs, MEN1 mutations and LOH are also reported, indicating common pathways in tumor development. Prevalence of thymic NETs (thNETs) and pulmonary carcinoids in MEN1 patients is 2-8%. Pulmonary carcinoids may be underreported and research on natural history is limited, but disease-related mortality is low. thNETs have a high mortality rate. Duodenopancreatic NETs (dpNETs) are multiple, almost universally found at pathology, and associated with precursor lesions. Gastrinomas are usually located in the duodenal submucosa while other dpNETs are predominantly pancreatic. dpNETs are an important determinant of MEN1-related survival, with an estimated 10-year survival of 75%. Survival differs between subtypes and apart from tumor size there are no known prognostic factors. Natural history of nonfunctioning pancreatic NETs needs to be redefined because of increased detection of small tumors. MEN1-related gastrinomas seem to behave similar to their sporadic counterparts, while insulinomas seem to be more aggressive. Investigations into the molecular functions of menin have led to new insights into MEN1-related tumorigenesis. Menin is involved in gene transcription, both as an activator and repressor. It is part of chromatin-modifying protein complexes, indicating involvement of epigenetic pathways in MEN1-related NET development. Future basic and translational research aimed at NETs in large unbiased cohorts will clarify the role of menin in NET tumorigenesis and might lead to new therapeutic options.
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Affiliation(s)
- C R C Pieterman
- Division of Internal Medicine and Dermatology, Department of Internal Medicine, University Medical Center Utrecht, Internal post number L.00.408, PO Box 85500, 3508 GA Utrecht, The Netherlands Division of Biomedical Genetics, Department of Molecular Cancer Research Division of Surgical Specialties, Department of Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
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Zhou Y, Zhang X, Klibanski A. Genetic and epigenetic mutations of tumor suppressive genes in sporadic pituitary adenoma. Mol Cell Endocrinol 2014; 386:16-33. [PMID: 24035864 PMCID: PMC3943596 DOI: 10.1016/j.mce.2013.09.006] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 09/03/2013] [Indexed: 12/28/2022]
Abstract
Human pituitary adenomas are the most common intracranial neoplasms. Approximately 5% of them are familial adenomas. Patients with familial tumors carry germline mutations in predisposition genes, including AIP, MEN1 and PRKAR1A. These mutations are extremely rare in sporadic pituitary adenomas, which therefore are caused by different mechanisms. Multiple tumor suppressive genes linked to sporadic tumors have been identified. Their inactivation is caused by epigenetic mechanisms, mainly promoter hypermethylation, and can be placed into two groups based on their functional interaction with tumor suppressors RB or p53. The RB group includes CDKN2A, CDKN2B, CDKN2C, RB1, BMP4, CDH1, CDH13, GADD45B and GADD45G; AIP and MEN1 genes also belong to this group. The p53 group includes MEG3, MGMT, PLAGL1, RASSF1, RASSF3 and SOCS1. We propose that the tumor suppression function of these genes is mainly mediated by the RB and p53 pathways. We also discuss possible tumor suppression mechanisms for individual genes.
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Affiliation(s)
- Yunli Zhou
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States
| | - Xun Zhang
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States
| | - Anne Klibanski
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States.
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Desai SS, Modali SD, Parekh VI, Kebebew E, Agarwal SK. GSK-3β protein phosphorylates and stabilizes HLXB9 protein in insulinoma cells to form a targetable mechanism of controlling insulinoma cell proliferation. J Biol Chem 2014; 289:5386-98. [PMID: 24425879 DOI: 10.1074/jbc.m113.533612] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Insulinomas (pancreatic islet β cell tumors) are the most common type of functioning pancreatic neuroendocrine tumors that occur sporadically or as a part of the MEN1 syndrome that is caused by germ line mutations in MEN1. Tissue-specific tumor predisposition from germ line mutations in ubiquitously expressed genes such as MEN1 could occur because of functional consequences on tissue-specific factors. We previously reported the proapoptotic β cell differentiation factor HLXB9 as a downstream target of menin (encoded by MEN1). Here we show that GSK-3β inactivates the proapoptotic activity of HLXB9 by phosphorylating HLXB9 at Ser-78/Ser-80 (pHLXB9). Although HLXB9 is found in the nucleus and cytoplasm, pHLXB9 is predominantly nuclear. Both pHLXB9 and active GSK-3β are elevated in β cells with menin knockdown, in MEN1-associated β cell tumors (insulinomas), and also in human sporadic insulinomas. Pharmacologic inhibition of GSK-3β blocked cell proliferation in three different rodent insulinoma cell lines by arresting the cells in G2/M phase and caused apoptosis. Taken together, these data suggest that the combination of GSK-3β and pHLXB9 forms a therapeutically targetable mechanism of insulinoma pathogenesis. Our results reveal that GSK-3β and pHLXB9 can serve as novel targets for insulinoma treatment and have implications for understanding the pathways associated with β cell proliferation.
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Affiliation(s)
- Shruti S Desai
- From the Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892 and
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Hamze Z, Vercherat C, Bernigaud-Lacheretz A, Bazzi W, Bonnavion R, Lu J, Calender A, Pouponnot C, Bertolino P, Roche C, Stein R, Scoazec JY, Zhang CX, Cordier-Bussat M. Altered MENIN expression disrupts the MAFA differentiation pathway in insulinoma. Endocr Relat Cancer 2013; 20:833-48. [PMID: 24157940 PMCID: PMC3841063 DOI: 10.1530/erc-13-0164] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The protein MENIN is the product of the multiple endocrine neoplasia type I (MEN1) gene. Altered MENIN expression is one of the few events that are clearly associated with foregut neuroendocrine tumours (NETs), classical oncogenes or tumour suppressors being not involved. One of the current challenges is to understand how alteration of MENIN expression contributes to the development of these tumours. We hypothesised that MENIN might regulate factors maintaining endocrine-differentiated functions. We chose the insulinoma model, a paradigmatic example of well-differentiated pancreatic NETs, to study whether MENIN interferes with the expression of v-MAF musculoaponeurotic fibrosarcoma oncogene homologue A (MAFA), a master glucose-dependent transcription factor in differentiated β-cells. Immunohistochemical analysis of a series of human insulinomas revealed a correlated decrease in both MENIN and MAFA. Decreased MAFA expression resulting from targeted Men1 ablation was also consistently observed in mouse insulinomas. In vitro analyses using insulinoma cell lines showed that MENIN regulated MAFA protein and mRNA levels, and bound to Mafa promoter sequences. MENIN knockdown concomitantly decreased mRNA expression of both Mafa and β-cell differentiation markers (Ins1/2, Gck, Slc2a2 and Pdx1) and, in parallel, increased the proliferation rate of tumours as measured by bromodeoxyuridine incorporation. Interestingly, MAFA knockdown alone also increased proliferation rate but did not affect the expression of candidate proliferation genes regulated by MENIN. Finally, MENIN variants with missense mutations detected in patients with MEN1 lost the WT MENIN properties to regulate MAFA. Together, our findings unveil a previously unsuspected MENIN/MAFA connection regarding control of the β-cell differentiation/proliferation balance, which could contribute to tumorigenesis.
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MESH Headings
- Adult
- Aged
- Animals
- Apoptosis
- Blotting, Western
- Carcinoma, Neuroendocrine/genetics
- Carcinoma, Neuroendocrine/metabolism
- Carcinoma, Neuroendocrine/pathology
- Cell Differentiation
- Cell Proliferation
- Chromatin Immunoprecipitation
- Female
- Glucose/pharmacology
- Humans
- Immunoenzyme Techniques
- Insulin-Secreting Cells/metabolism
- Insulin-Secreting Cells/pathology
- Insulinoma/genetics
- Insulinoma/metabolism
- Insulinoma/pathology
- Maf Transcription Factors, Large/antagonists & inhibitors
- Maf Transcription Factors, Large/genetics
- Maf Transcription Factors, Large/metabolism
- Male
- Mice
- Mice, Knockout
- Middle Aged
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Proto-Oncogene Proteins/antagonists & inhibitors
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins/physiology
- RNA, Messenger/genetics
- RNA, Small Interfering/genetics
- Rats
- Real-Time Polymerase Chain Reaction
- Reverse Transcriptase Polymerase Chain Reaction
- Tumor Cells, Cultured
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Affiliation(s)
- Z Hamze
- INSERM U1052/CNRS UMR5286/Université de Lyon, Lyon1 UMR-S1052, Cancer Research Center of Lyon, Lyon F-69008, France Service de Génétique Moléculaire et Clinique, Hospices Civils de Lyon, Hôpital Edouard Herriot, Lyon F-69437, France UMR 3347/CNRS, U1021/INSERM, Institut Curie, Orsay F-91405, France Service Central d'Anatomie et Cytologie Pathologiques, Hospices Civils de Lyon, Hôpital Edouard Herriot, Lyon F-69437, France Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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Menin: a scaffold protein that controls gene expression and cell signaling. Trends Biochem Sci 2013; 38:394-402. [PMID: 23850066 DOI: 10.1016/j.tibs.2013.05.005] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/22/2013] [Accepted: 05/31/2013] [Indexed: 12/22/2022]
Abstract
The protein menin is encoded by the MEN1 gene, which is mutated in patients with multiple endocrine neoplasia type 1 (MEN1) syndrome. Although menin acts as a tumor suppressor in endocrine organs, it is required for leukemic transformation in mouse models. Menin possesses these dichotomous functions probably because it can both positively and negatively regulate gene expression, as well as interact with a multitude of proteins with diverse functions. Here, we review the recent progress in understanding the molecular mechanisms by which menin functions. The crystal structures of menin with different binding partners reveal that menin is a key scaffold protein that functionally crosstalks with various partners to regulate gene transcription and interplay with multiple signaling pathways.
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