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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pancreatic endocrine tumors and GIST : clinical markers, epidemiology and treatment /

Ekeblad, Sara, January 2007 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2007. / Härtill 4 uppsatser.
2

Functional studies of the multiple endocrine neoplasia type 1 gene /

Bylund, Lovisa, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
3

Frequência da neoplasia endócrina múltipla tipo 1 em grupos de pacientes com adenoma hipofisário: aspectos clínicos e estudo genético familiar

Nunes, Vânia dos Santos [UNESP] 07 August 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-07Bitstream added on 2014-06-13T18:43:12Z : No. of bitstreams: 1 nunes_vs_dr_botfm.pdf: 1297313 bytes, checksum: 470ba33e35f9a75851e361e40639894a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A Neoplasia Endócrina Múltipla tipo 1 (MEN1; OMIM 131100) é uma doença genética, herdada de forma autossômica dominante, caracterizada pela presença de tumores em pelo menos dois dos seguintes tecidos endócrinos: paratireóide, enteropancreático e adenohipófise. Além destes componentes maiores, tumores adrenocorticais, carcinóides, lipomatose, angiofibroma e colagenoma facial têm sido associados. Trata-se de uma síndrome rara com uma prevalência estimada de 2-3/100000 indivíduos, causada por mutações inativadoras no gene MEN1. Este, por sua vez, codifica uma proteína chamada menin, que tem demonstrado interagir com diversas proteínas envolvidas em processos celulares essenciais, como controle do crescimento e ciclo celular, reparo de DNA, regulação da transcrição gênica, regulação estabilidade genômica, e controle da apoptose. A identificação do gene MEN1 possibilitou a detecção de mutações causadoras da doença e, com isto, a confirmação do diagnóstico clínico em pacientes acometidos, bem como o diagnóstico precoce em familiares assintomáticos. É preconizada a pesquisa dos principais tumores associados a MEN1 em pacientes já com o diagnóstico da síndrome ou nos portadores da mutação, mas a abordagem inversa que é a investigação da MEN1 em pacientes com diagnóstico inicial apenas de um dos principais tumores associados tem sido pouco explorada. Por isto, esta pesquisa consistiu em... / Multiple endocrine neoplasia type 1 (MEN1; OMIM 131100) is a genetic disease, inherited in the dominant autosomal form and characterized by the presence of tumors in at least two of the following endocrine tissues: parathyroid, enteropancreatic and adenopituitary. Besides the aforementioned major components, adrenocortical and carcinoid tumors, lipomas, collagenomas and facial angiofibromas have been associated with the disease. MEN1 is a rare disease, with an estimated prevalence of 2-3/100000 individuals; it is caused by inactivated mutations of the MEN1 gene. This gene encodes one protein called menin, which has been shown to interact with a number of proteins that are involved in essential cell processes such as cell division and proliferation, DNA repair, transcriptional regulation, genome stability, and apoptosis control. The MEN1 gene identification has enabled the detection of MEN1 mutations and the confirmation of the disease’s clinical diagnosis as well as its early diagnosis in asymptomatic relatives. The screening of these principal tumors associated with MEN1 has been recommended in patients with MEN1 syndrome or MEN1 mutation. However, the inverse approach (i.e., the investigation of MEN1 in patients with an initial diagnosis of only one of the principal tumors) has been little explored. For this reason, the present study aimed to evaluate the frequency of MEN1 in a group the patients with pituitary adenoma (PA), and to identify, in these individuals, variables... (Complete abstract click electronic access below)
4

Frequência da neoplasia endócrina múltipla tipo 1 em grupos de pacientes com adenoma hipofisário : aspectos clínicos e estudo genético familiar /

Nunes, Vania dos Santos. January 2009 (has links)
Orientador: Célia Regina Nogueira / Banca: Cesar Luiz Boguszewski / Banca: Fernando Rodrigues Pimentel Filho / Banca: Glaucia M. F. S. Mazeto / Banca: Evandro de Souza Portes / Resumo: A Neoplasia Endócrina Múltipla tipo 1 (MEN1; OMIM 131100) é uma doença genética, herdada de forma autossômica dominante, caracterizada pela presença de tumores em pelo menos dois dos seguintes tecidos endócrinos: paratireóide, enteropancreático e adenohipófise. Além destes componentes maiores, tumores adrenocorticais, carcinóides, lipomatose, angiofibroma e colagenoma facial têm sido associados. Trata-se de uma síndrome rara com uma prevalência estimada de 2-3/100000 indivíduos, causada por mutações inativadoras no gene MEN1. Este, por sua vez, codifica uma proteína chamada menin, que tem demonstrado interagir com diversas proteínas envolvidas em processos celulares essenciais, como controle do crescimento e ciclo celular, reparo de DNA, regulação da transcrição gênica, regulação estabilidade genômica, e controle da apoptose. A identificação do gene MEN1 possibilitou a detecção de mutações causadoras da doença e, com isto, a confirmação do diagnóstico clínico em pacientes acometidos, bem como o diagnóstico precoce em familiares assintomáticos. É preconizada a pesquisa dos principais tumores associados a MEN1 em pacientes já com o diagnóstico da síndrome ou nos portadores da mutação, mas a abordagem inversa que é a investigação da MEN1 em pacientes com diagnóstico inicial apenas de um dos principais tumores associados tem sido pouco explorada. Por isto, esta pesquisa consistiu em... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Multiple endocrine neoplasia type 1 (MEN1; OMIM 131100) is a genetic disease, inherited in the dominant autosomal form and characterized by the presence of tumors in at least two of the following endocrine tissues: parathyroid, enteropancreatic and adenopituitary. Besides the aforementioned major components, adrenocortical and carcinoid tumors, lipomas, collagenomas and facial angiofibromas have been associated with the disease. MEN1 is a rare disease, with an estimated prevalence of 2-3/100000 individuals; it is caused by inactivated mutations of the MEN1 gene. This gene encodes one protein called menin, which has been shown to interact with a number of proteins that are involved in essential cell processes such as cell division and proliferation, DNA repair, transcriptional regulation, genome stability, and apoptosis control. The MEN1 gene identification has enabled the detection of MEN1 mutations and the confirmation of the disease's clinical diagnosis as well as its early diagnosis in asymptomatic relatives. The screening of these principal tumors associated with MEN1 has been recommended in patients with MEN1 syndrome or MEN1 mutation. However, the inverse approach (i.e., the investigation of MEN1 in patients with an initial diagnosis of only one of the principal tumors) has been little explored. For this reason, the present study aimed to evaluate the frequency of MEN1 in a group the patients with pituitary adenoma (PA), and to identify, in these individuals, variables... (Complete abstract click electronic access below) / Doutor
5

Multiple Endocrine Neoplasia Type 1 (MEN1) and Pituitary Adenoma Predisposition (PAP) in Northern Finland

Vierimaa, O. (Outi) 17 June 2008 (has links)
Abstract Multiple endocrine neoplasia type 1 (MEN1) is an inherited syndrome characterized by parathyroid, gastroenteropancreatic and pituitary neuroendocrine tumours. In Northern Finland, two founder mutations of the MEN1 gene (1466del12, 1657insC) accounting for the majority of the MEN1 cases, have common ancestors born in the 18th and 19th centuries, respectively. Three small clusters of familial pituitary adenoma have also been detected, two of which could be linked by genealogy to a common ancestral couple born in the 18th century. Clinical evaluation of 82 MEN1 mutation carriers showed that age was a risk factor for most of the MEN1-related manifestations. In the whole group, nonfunctional pancreatic tumour (NFPT) was more common in the frameshift/nonsense mutation carriers (odds ratio 3.26; 95% confidence interval 1.27–8.33, P = 0.014), whereas gastrinoma was more common in the in-frame/missense mutation carriers (OR 6.77, CI 1.31–35.0, P = 0.022). In the founder mutation carriers, the 1657insC mutation predicted the risk for NFPT (OR 3.56, CI 1.29–9.83, P = 0.015), while the 1466del12 mutation was associated with the risk for gastrinoma (OR 15.1, CI 1.73–131.9, P = 0.014). The mean ages at death of the 32 obligatory MEN1 founder mutation carriers born between 1728 and 1929 were compared to those of the 29 spouses and sex-matched life expectancy estimates derived from Finnish national statistics. The ages at death of the mutation carrier males (61.1 ± 12.0 years) and females (67.2 ± 10.7 years) did not differ from the control groups. PAP (pituitary adenoma predisposition) locus was mapped in the chromosome region 11q12–11q13 by whole-genome single-nucleotide polymorphism genotyping. Combining the linkage and the gene expression array data, AIP (aryl hydrocarbon receptor interacting protein) was chosen for sequencing. The nonsense mutation Q14X was identified in the affected (acromegaly, gigantism, prolactinoma) family members and in four other patients. Loss of heterozygosity was detected in pituitary adenomas of AIP mutation carriers. Mutation analysis of MEN1, HRPT2 (hyperparathyroidism 2), CASR (calcium-sensing receptor), CDKN1B (cyclin-dependent kinase inhibitor 1B) and AIP genes was performed in primary hyperparathyroidism patients with features of inherited predisposition. One out of 29 patients was found to have the 1466del12 mutation, while no mutations were detected in other genes.
6

Rastreamento clínico de tumores endócrinos em jovens portadores de mutação MEN1 germinativa: avaliação do impacto clínico em relação aos critérios do consenso internacional de neoplasia endócrina múltipla tipo 1 / Clinical screening of endocrine tumors in children and adolescents harboring germline MEN1 mutation: analysis of clinical impact applying criteria adopted for International Consensus on multiple endocrine neoplasia type 1

Gonçalves, Tatiana Denck 26 June 2013 (has links)
Contexto: A neoplasia endócrina múltipla tipo 1 (NEM1) é uma doença familiar com padrão de herança autossômica dominante, caracterizada por uma susceptibilidade genética aumentada ao desenvolvimento de tumores nas paratireóides (HPT), hipófise (PIT) e células endócrinas do pâncreas e do duodeno (PET). A descoberta do gene MEN1 propiciou a identificação de mutação nos casos- índices e nos familiares sob-risco. O Consenso Internacional de NEM1 (2001) sugeriu a realização periódica de exames hormonais e radiológicos em portadores de mutação germinativa MEN1, visando o diagnóstico precoce de tumores. As idades de início do rastreamento se basearam na descrição do caso mais jovem para cada tipo tumoral. O novo Consenso internacional de NEM1 (2012), mantendo este critério, sugeriu antecipar o início do rastreamento de tumores endócrinos pancreáticos não funcionantes (NF-PET) dos 20 para os 10 anos de idade, baseando-se no relato de dois casos jovens. A penetrância, a prevalência e o fenótipo dos tumores NEM1 em jovens com idade <21 anos ainda não foram satisfatoriamente determinados Objetivo: Avaliar a penetrância, a prevalência e o impacto clínico de tumores diagnosticados na 2ª década de vida em portadores de mutação germinativa MEN1 Casuística: É constituída por 113 portadores de mutação MEN1. Dois subgrupos foram selecionados para avaliar a penetrância e a prevalência na 2ª década: 27, avaliados durante a 2ª década e; 24, com início de sintomas relacionados à NEM1 nesta faixa etária (< 21anos) e diagnóstico após esta idade. Resultados: Considerando os 113 casos com NEM1, a distribuição percentual de casos diagnosticados ou com sintomas relacionados que se iniciaram na 2ª década de vida com HPT, PET, insulinoma, gastrinoma, NF-PET, PIT, prolactinoma e NF-PIT foi respectivamente: 29,5; 10,5; 25; 0; 10; 33,9; 48,5, e; 15,8%. Na segunda década, a penetrância de HPT, PET e PIT foi 66,7%, 42,1 % e 54,5% enquanto que a prevalência destes tumores foi de 76,2% %, 50% e 60%. A metade dos casos deste grupo jovem, com presença de tumores na 2ª década, era sintomática (52.4%; 11/21) sendo que os sintomas relacionados ao prolactinoma eram os mais prevalentes na admissão (81,8%) seguidos dos relacionados ao insulinoma (18,2%) e HPT (9%). Prolactinoma foi o tumor hipofisário mais prevalente (75%) e clinicamente relevante, sendo que 55,6% deles eram macroadenomas (>= 10 mm). PITs não funcionantes (NF-PIT) foram menos frequentes (3/12; 25%) e se apresentaram como microadenomas incipientes. NF-PETs foram frequentes na segunda década (8/16; 50%) e clinicamente relevantes uma vez que 62,5% dos casos tinha indicação cirúrgica. Insulinomas basicamente representaram os PETs funcionantes nesta faixa etária. Apesar da maioria dos casos com HPT serem assintomáticos ao diagnóstico (15/16; 93.8%), um quarto deles (25%) apresentaram nefrolitíase antes dos 20 anos. Conclusões: HPT, prolactinomas, insulinomas e NF-PETs representam os tumores relacionados à NEM1 de maior relevância clínica durante a 2ª década de vida. Nossos dados indicam que um rastreamento clínico/hormonal e radiológico ostensivo deve ser conduzido direcionado ao diagnóstico destes tumores em jovens portadores de mutação germinativa MEN1 / Context: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder with high susceptibility to developing endocrine tumors in pituitary (PIT) and parathyroids glands (HPT) and endocrine cells from duodenum and pancreatic islets (PET). Genetic status of index cases and at-risk familial members was possible after MEN1 gene discovery. Genetic screening of MEN1 families has substantially improved the clinical management of MEN1. In order to reach an early diagnosis, the Consensus on MEN1 (2001) established periodic hormonal/radiological exams in MEN1 carriers with beginning to each tumor type based on younger case age reported so far. Recently, non-functioning PETs (NF- PET) were described in two cases in younger ages (2nd decade) than that defined by Consensus (20 y-old or more). Recently, the 2012 clinical practice guideline on MEN1 suggested the anticipation of the screening for NF-PETs from 20 to 10 years of age. However, data on the penetrance of MEN1-related tumors in young MEN1 patients (<21y-old) are scarce. Objective: Estimate the penetrance, prevalence and clinical impact resultant of the early diagnosis of MEN1-related tumors in young MEN1 carriers. Design: Data obtained from a MEN1 screening program (1996- 2012). Setting: Tertiary academic reference center. Patients: 27 young MEN1 cases prospectively followed during the first two decades of life, belonging to an overall casuistic of 113 MEN1 cases harboring MEN1 germline mutations; Methods: Appropriate biochemical and imaging studies. Results: In the present setting, the percentage values of the each one of the MEN1-related tumors recognized during 2nd decade in our 113 MEN1 cases were: HPT (29.5%); PET (10.5%); insulinoma (25%); gastrinoma (0%), non-functioning PET (10%); PIT (33.9%), prolactinoma (48.5%); and NF-PIT (15.8%). In 27 MEN1-mutation positive patients younger than 21y-old, the penetrance and prevalence of HPT, PET and PIT were, respectively, 66.7%, 42.1%, 54.5% and 76.2%, 50%, 60%. Half of young cases were asymptomatic. Symptoms were mostly related with prolactinoma (81.8%), insulinoma (18.2%) and HPT (9%). Prolactinoma was highly prevalent (75%) and most (55.5%) were macroadenoma. NF-PITs (25%) had no clinical relevance. Asymptomatic NF-PETs were frequent (50%) and relevant clinically (62.5%). Considering the functioning PETs, only insulinoma was present in young MEN1 subset. One quarter of all HPT patients exhibited MEN1-related urolithiasis in the second decade. Conclusions: Our MEN1 series documented a high prevalence of clinically relevant HPT, prolactinoma, insulinoma and NF-PETs and its comorbidities during the second decade of life. These data suggest the need for strict surveillance of these tumors in MEN1 mutation carriers during late childhood and adolescence
7

Endocrine tumour development : with special focus on chromosome arms 1p and 11q /

Nord, Brita, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 7 uppsatser.
8

Localization and characterization of genes involved in parathyroid tumor development /

Forsberg, Lars, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.
9

Rastreamento clínico de tumores endócrinos em jovens portadores de mutação MEN1 germinativa: avaliação do impacto clínico em relação aos critérios do consenso internacional de neoplasia endócrina múltipla tipo 1 / Clinical screening of endocrine tumors in children and adolescents harboring germline MEN1 mutation: analysis of clinical impact applying criteria adopted for International Consensus on multiple endocrine neoplasia type 1

Tatiana Denck Gonçalves 26 June 2013 (has links)
Contexto: A neoplasia endócrina múltipla tipo 1 (NEM1) é uma doença familiar com padrão de herança autossômica dominante, caracterizada por uma susceptibilidade genética aumentada ao desenvolvimento de tumores nas paratireóides (HPT), hipófise (PIT) e células endócrinas do pâncreas e do duodeno (PET). A descoberta do gene MEN1 propiciou a identificação de mutação nos casos- índices e nos familiares sob-risco. O Consenso Internacional de NEM1 (2001) sugeriu a realização periódica de exames hormonais e radiológicos em portadores de mutação germinativa MEN1, visando o diagnóstico precoce de tumores. As idades de início do rastreamento se basearam na descrição do caso mais jovem para cada tipo tumoral. O novo Consenso internacional de NEM1 (2012), mantendo este critério, sugeriu antecipar o início do rastreamento de tumores endócrinos pancreáticos não funcionantes (NF-PET) dos 20 para os 10 anos de idade, baseando-se no relato de dois casos jovens. A penetrância, a prevalência e o fenótipo dos tumores NEM1 em jovens com idade <21 anos ainda não foram satisfatoriamente determinados Objetivo: Avaliar a penetrância, a prevalência e o impacto clínico de tumores diagnosticados na 2ª década de vida em portadores de mutação germinativa MEN1 Casuística: É constituída por 113 portadores de mutação MEN1. Dois subgrupos foram selecionados para avaliar a penetrância e a prevalência na 2ª década: 27, avaliados durante a 2ª década e; 24, com início de sintomas relacionados à NEM1 nesta faixa etária (< 21anos) e diagnóstico após esta idade. Resultados: Considerando os 113 casos com NEM1, a distribuição percentual de casos diagnosticados ou com sintomas relacionados que se iniciaram na 2ª década de vida com HPT, PET, insulinoma, gastrinoma, NF-PET, PIT, prolactinoma e NF-PIT foi respectivamente: 29,5; 10,5; 25; 0; 10; 33,9; 48,5, e; 15,8%. Na segunda década, a penetrância de HPT, PET e PIT foi 66,7%, 42,1 % e 54,5% enquanto que a prevalência destes tumores foi de 76,2% %, 50% e 60%. A metade dos casos deste grupo jovem, com presença de tumores na 2ª década, era sintomática (52.4%; 11/21) sendo que os sintomas relacionados ao prolactinoma eram os mais prevalentes na admissão (81,8%) seguidos dos relacionados ao insulinoma (18,2%) e HPT (9%). Prolactinoma foi o tumor hipofisário mais prevalente (75%) e clinicamente relevante, sendo que 55,6% deles eram macroadenomas (>= 10 mm). PITs não funcionantes (NF-PIT) foram menos frequentes (3/12; 25%) e se apresentaram como microadenomas incipientes. NF-PETs foram frequentes na segunda década (8/16; 50%) e clinicamente relevantes uma vez que 62,5% dos casos tinha indicação cirúrgica. Insulinomas basicamente representaram os PETs funcionantes nesta faixa etária. Apesar da maioria dos casos com HPT serem assintomáticos ao diagnóstico (15/16; 93.8%), um quarto deles (25%) apresentaram nefrolitíase antes dos 20 anos. Conclusões: HPT, prolactinomas, insulinomas e NF-PETs representam os tumores relacionados à NEM1 de maior relevância clínica durante a 2ª década de vida. Nossos dados indicam que um rastreamento clínico/hormonal e radiológico ostensivo deve ser conduzido direcionado ao diagnóstico destes tumores em jovens portadores de mutação germinativa MEN1 / Context: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder with high susceptibility to developing endocrine tumors in pituitary (PIT) and parathyroids glands (HPT) and endocrine cells from duodenum and pancreatic islets (PET). Genetic status of index cases and at-risk familial members was possible after MEN1 gene discovery. Genetic screening of MEN1 families has substantially improved the clinical management of MEN1. In order to reach an early diagnosis, the Consensus on MEN1 (2001) established periodic hormonal/radiological exams in MEN1 carriers with beginning to each tumor type based on younger case age reported so far. Recently, non-functioning PETs (NF- PET) were described in two cases in younger ages (2nd decade) than that defined by Consensus (20 y-old or more). Recently, the 2012 clinical practice guideline on MEN1 suggested the anticipation of the screening for NF-PETs from 20 to 10 years of age. However, data on the penetrance of MEN1-related tumors in young MEN1 patients (<21y-old) are scarce. Objective: Estimate the penetrance, prevalence and clinical impact resultant of the early diagnosis of MEN1-related tumors in young MEN1 carriers. Design: Data obtained from a MEN1 screening program (1996- 2012). Setting: Tertiary academic reference center. Patients: 27 young MEN1 cases prospectively followed during the first two decades of life, belonging to an overall casuistic of 113 MEN1 cases harboring MEN1 germline mutations; Methods: Appropriate biochemical and imaging studies. Results: In the present setting, the percentage values of the each one of the MEN1-related tumors recognized during 2nd decade in our 113 MEN1 cases were: HPT (29.5%); PET (10.5%); insulinoma (25%); gastrinoma (0%), non-functioning PET (10%); PIT (33.9%), prolactinoma (48.5%); and NF-PIT (15.8%). In 27 MEN1-mutation positive patients younger than 21y-old, the penetrance and prevalence of HPT, PET and PIT were, respectively, 66.7%, 42.1%, 54.5% and 76.2%, 50%, 60%. Half of young cases were asymptomatic. Symptoms were mostly related with prolactinoma (81.8%), insulinoma (18.2%) and HPT (9%). Prolactinoma was highly prevalent (75%) and most (55.5%) were macroadenoma. NF-PITs (25%) had no clinical relevance. Asymptomatic NF-PETs were frequent (50%) and relevant clinically (62.5%). Considering the functioning PETs, only insulinoma was present in young MEN1 subset. One quarter of all HPT patients exhibited MEN1-related urolithiasis in the second decade. Conclusions: Our MEN1 series documented a high prevalence of clinically relevant HPT, prolactinoma, insulinoma and NF-PETs and its comorbidities during the second decade of life. These data suggest the need for strict surveillance of these tumors in MEN1 mutation carriers during late childhood and adolescence
10

Pancreatic Endocrine Tumourigenesis : Genes of potential importance

Johansson, Térèse A. January 2008 (has links)
<p>Understanding signalling pathways that control pancreatic endocrine tumour (PET) development and proliferation may reveal novel targets for therapeutic intervention. The pathogenesis for sporadic and hereditary PETs, apart from mutations of the <i>MEN1</i> and <i>VHL</i> tumour suppressor genes, is still elusive. The protein product of the <i>MEN1</i> gene, menin, regulates many genes. The aim of this thesis was to identify genes involved in pancreatic endocrine tumourigenesis, with special reference to Notch signalling.</p><p>Messenger RNA and protein expression of NOTCH1, HES1, HEY1, ASCL1, NEUROG3, NEUROD1, DLK1, POU3F4, PDX1, RPL10, DKK1 and TPH1 were studied in human PETs, sporadic and MEN 1, as well as in tumours from heterozygous <i>Men1</i> mice. For comparison, normal and <i>MEN1</i> non-tumourous human and mouse pancreatic specimens were used. Nuclear expression of HES1 was consistently absent in PETs. In mouse tumours this coincided with loss of menin expression, and there was a correlation between <i>Men1</i> expression and several Notch signalling factors. A new phenotype consisting of numerous menin-expressing endocrine cell clusters, smaller than islets, was found in <i>Men1</i> mice. Expression of NEUROG3 and NEUROD1 was predominantly localised to the cytoplasm in PETs and islets from MEN 1 patients and <i>Men1</i> mice, whereas expression was solely nuclear in wt mice. Differences in expression levels of Pou3f4, Rpl10 and Dlk1 between islets of <i>Men1</i> and wt mice were observed.</p><p>In addition, combined RNA interference and microarray expression analysis in the pancreatic endocrine cell line BON1 identified 158 target genes of ASCL1. For two of these, DKK1 (a negative regulator of the WNT/β-catenin signalling pathway) and TPH1, immunohistochemistry was performed on PETs. In concordance with the microarray finding, DKK1 expression showed an inverse relation to ASCL1 expression.</p><p>Altered subcellular localisation of HES1, NEUROD1 and NEUROG3 and down-regulation of DKK1 may contribute to tumourigenesis.</p>

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