• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 4
  • 1
  • 1
  • Tagged with
  • 10
  • 10
  • 5
  • 4
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 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

Human eosinophils and their activation by allergens via danger receptors

Redvall, Elin, January 2010 (has links)
Diss. (sammanfattning) Göteborg : Univ. , 2010.
2

Maternally Inherited Peptides Are Strain Specific Chemosignals That Activate a New Candidate Class of Vomeronasal Chemosensory Receptor

Roberts, Richard William January 2009 (has links)
<p>The chemical cues that provide an olfactory portrait of mammalian individuals are in part detected by chemosensory receptors in the vomeronasal organ (VNO). By and large, the pertinent receptor-cue combinations used for olfactory communication are unidentified. Here we identify members of the formyl peptide receptor (FPR) family of G protein coupled receptors as candidate chemosensory receptors in the VNO of mice. We demonstrate that N-formylated mitochondrially encoded peptides presented by the major histocompatibility complex (MHC) molecule H2-M3 stimulate a subset of the VNO sensory neurons (VSNs). We show that one VNO localized FPR, Fpr-rs1, is differentially activated by strain specific variants of N-formylated peptides. We show that N-formylated peptides can function as chemosignals in a strain selective pregnancy block. We propose that this link between self-recognition peptides of the immune system and chemosensory pathways provides a possible molecular means to communicate the nature of an individual's maternal lineage or strain.</p> / Dissertation
3

Použití agonistů FPR receptorů pro terapii nádorových onemocnění / The use of agonists of formyl peptide receptors for cancer therapy

CAISOVÁ, Veronika January 2013 (has links)
The main goal of the thesis was to optimize the use of agonists of the FPR receptors for cancer therapy. The aim was: (1) to find the best anchor of ligands to the cancer cells and the optimal timing of the treatment, (2) to verify the universality of agonists of FPR receptors for different types of cancer, (3) to explain the synergy between ligands of FPR and ligands of TLR by flow cytometry and (4) to verify the applicability of cytotoxic test CD45+/ PI for f-MLF-DOPE ligand.
4

On nogo signaling regulation /

Trifunovski, Alexandra, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 7 uppsatser.
5

Alterações na expressão de receptores de peptídeos formilados, citocinas e monócitos que auxiliam no colapso vascular e imunológico da sepse / Changes in the expression of formyl peptide receptors, cytokines, and monocytes that aid in the vascular and immune collapse of sepsis

Alves, Patrícia Terra 16 October 2017 (has links)
A tese encontra-se em formato de artigos conforme norma do Programa de Pós-graduação em Genética e Bioquímica da Universidade Federal de Uberlândia. Esta tese é composta por 4 capítulos, sendo o primeiro capítulo a revisão bibliografica a qual foi escrita em português de acordo com as normas da ABNT e os demais capítulos refere-se a artigos científicos os quais estão em inglês e obdecem as normas das revistas científicas as quais serão submetidos. / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / A sepse é uma síndrome clínica grave responsável por grande parte dos óbitos nas Unidades de Terapia Intensiva. Há uma diversidade de causas primárias que podem evoluir para um quadro clínico de sepse o que dificulta o diagnóstico precoce e a descoberta de drogas eficientes para tratamento. Os altos custos dos tratamentos e as taxas de letalidade mundial demonstram a necessidade de uma melhor compreensão desta síndrome. Este estudo buscou avaliar a expressão gênica dos Receptores de Peptídeos Formilados (FPR) em leucócitos totais, análise de marcadores sistêmicos e o perfil proteínas globais dos monócitos para averiguar as alterações presentes no organismo do indivíduo com a síndrome da sepse. Foi realizado a caracterização das alterações sistêmicas responsáveis pelo óbito de pacientes com sepse através da quantificação simultânea de 27 biomarcadores; verificou-se o silenciamento da expressão gênica do FPR1 e o FPR2 em pacientes com sepse e choque, relatando as possíveis disfunções imunológicas provocadas pela ausência desses FPRs; e a análise proteômica dos monócitos de pacientes com choque séptico permitiu averiguar a contribuição dessa célula no colapso desta síndrome, sua influência na lesão vascular, endotoxemia, inflamação e trombose. Esta investigação identificou pela primeira vez alvos biológicos relevantes os quais podem desempenhar papeis importantes no diagnóstico, prognóstico e terapêutica. / Sepsis is a serious clinical syndrome responsible for most of the deaths in the Intensive Care Units. There are a number of primary causes that may develop for a clinical picture of sepsis, making it difficult to diagnose early and find effective treatment medications. The high costs of treatments and global lethality rates demonstrate the need for a better understanding of this syndrome. This study aimed to evaluate the gene expression of Formulated Peptide Receptors (FPR) in total leukocytes, analysis of systemic markers and the profile of monocyte global proteins to ascertain the changes present in the body of the individual with sepsis syndrome. The characterization of the systemic changes responsible for the death of patients with sepsis was carried out through the simultaneous quantification of 27 biomarkers. The silencing of the gene expression of FPR1 and FPR2 in patients with sepsis and septic shock, reporting as possible immunological dysfunctions caused by the absence of these FPRs. The proteomic analysis of the monocytes of patients with septic shock allowed us to investigate the contribution of this cell in the collapse of this syndrome, its influence on vascular injury, endotoxemia, inflammation and thrombosis. This research identified for the first time, what is more important for the diagnosis, prognosis and therapeutics. / Tese (Doutorado)
6

Endothelial factors in the pathogenesis of aortic valve stenosis

Peltonen, T. (Tuomas) 09 December 2008 (has links)
Abstract Calcified aortic valve disease represents a spectrum of disease spanning from mild aortic valve sclerosis to severe aortic valve stenosis (AS), being an actively regulated disease process and showing some hallmarks of atherosclerosis. The calcified aortic valve lesion develops endothelial injury and is characterized by inflammation, lipid accumulation, renin-angiotensin system activation and fibrosis. There is no approved pharmacological treatment available in AS. This study was aimed to characterize gene expression of endothelial factors in aortic valves in patients representing different stages of calcified aortic valve disease to reveal new targets for pharmacological interventions in AS. Aortic valves obtained from 75 patients undergoing valve replacement surgery were studied. Expression of natriuretic peptides (ANP, BNP and CNP), their processing enzymes (corin and furin), natriuretic receptors (NPR-A, NPR-B and NPR-C), endothelin-1 (ET-1), endothelin converting enzyme-1 (ECE-1), endothelin receptors A and B (ETA and ETB), and apelin pathway (apelin and its receptor APJ) was characterized by reverse-transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry. AS was characterized by distinct downregulation of gene expression of CNP, its processing enzyme furin and the target receptor NPR-B. Furthermore, increased amount of ET-1 and its target receptor ETA as well as imbalance between ETA and ETB receptors and downregulated endothelial nitric oxide synthase (eNOS) gene expression were observed. Finally, gene expression of apelin and APJ receptor were significantly upregulated in stenotic valves when compared to controls in combination with disequilibrium between expression of angiotensin II receptors AT1 and AT2. The study provides a better understanding of molecular mechanisms associated with calcific aortic valve disease and suggest potential targets for novel therapeutic interventions.
7

Análise da heterogeneidade dos mastócitos e expressão da proteína Anexina A1 e receptores FPR em variáveis clínico-patológicas de lesões uterinas / Analysis of mast cell heterogeneity and expression of the Annexin A1 protein and FPR receptors in clinicopathological variables of uterine lesions

Costa, Sara de Souza [UNESP] 02 March 2017 (has links)
Submitted by SARA DE SOUZA COSTA null (sarah_sc_0705@hotmail.com) on 2017-03-30T13:36:06Z No. of bitstreams: 1 Dissertação Sara de Souza Costa.pdf: 2766240 bytes, checksum: 20b447fe5bf3c49e40aa0b5fdf4dff1f (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2017-04-06T13:29:26Z (GMT) No. of bitstreams: 1 costa_ss_me_sjrp.pdf: 2766240 bytes, checksum: 20b447fe5bf3c49e40aa0b5fdf4dff1f (MD5) / Made available in DSpace on 2017-04-06T13:29:26Z (GMT). No. of bitstreams: 1 costa_ss_me_sjrp.pdf: 2766240 bytes, checksum: 20b447fe5bf3c49e40aa0b5fdf4dff1f (MD5) Previous issue date: 2017-03-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As lesões uterinas são causas importantes de desconforto, infertilidade e óbito entre as mulheres no Brasil e no mundo. O câncer de endométrio é um tumor maligno frequente e sua incidência vem aumentando nas últimas décadas. Enquanto, o tumor uterino benigno mais comum, o leiomioma, acomete cerca de 40% das mulheres na idade reprodutiva, sendo relacionado à menorragia, dismenorreia e infertilidade. Investigações indicam que o microambiente tumoral é crucial para o avanço do câncer, sendo caracterizado, principalmente, pela composição alterada da matriz extracelular, alta densidade de microvasos e abundância de células inflamatórias, como mastócitos (MCs). MCs desgranulados liberam fatores quimiotáticos e proteases, como triptase e quimase, para o meio extracelular, contribuindo na degradação da matriz extracelular, promoção da angiogênese, propiciando ambiente favorável para invasão tumoral e remodelação tecidual por meio de proteólises seletivas na matriz e ativação de metaloproteinases. Outro aspecto importante no crescimento tumoral é a proteína anti-inflamatória Anexina A1 (ANXA1), relacionada à regulação dos processos de crescimento e migração/invasão celular, sendo seus efeitos mediados por receptores para peptídeos formilados (FPRs), especialmente FPR1 e FPR2. Diante da importância dos MCs e da ANXA1/FPR no desenvolvimento tumoral, o objetivo desta investigação foi analisar a heterogeneidade dos MCs e a expressão das proteínas ANXA1, FPR1 e FPR2 em biópsias humanas das variáveis clínico-patológicas de útero normal: hiperplasia endometrial simples (HES), adenomiose, leiomiomas e adenocarcinoma (ADC) endometrial de graus I e II. Os MCs foram quantificados de acordo com seu estado de ativação e expressão das proteases triptase e quimase. A expressão da ANXA1 e seus receptores FPR1 e FPR2 nos MCs e tecidos uterinos foram analisadas nas diferentes biópsias estudadas. Nossos resultados mostraram MCs intactos e desgranulados, no endométrio e miométrio normais e aumentados na HES, margens tumorais nos leiomiomas, adenomiose e ADC endometrial de graus I e II, e diminuídos significantemente na região tumoral do leiomioma. Com relação à heterogeneidade, os MCs triptase-positivos foram observados em maior quantidade. As expressões endógenas da ANXA1 e do FPR1 foram observadas nos tecidos uterinos e MCs, com ausência para o FPR2. As modulações dos MCs, da proteína ANXA1 e de modo específico do receptor FPR1, nas variáveis clínico-patológicas das lesões uterinas investigadas indicam o envolvimento dessas células e a interação ANXA1/FPR1 no desenvolvimento de inflamação e neoplasia uterina. / Uterine lesions are important causes of discomfort, infertility and death among women in Brazil and in the world. Endometrial cancer is a frequent malignant tumor and its incidence has been increasing in the last decades. Besides, the most common benign uterine tumor, leiomyoma, affects about 40% of women at reproductive age, being related to menorrhagia, dysmenorrhea and infertility. Investigations indicate that the tumor microenvironment is crucial for the advancement of cancer, being characterized mainly by the altered composition of the extracellular matrix, high microvessel density and abundance of inflammatory cells, such as mast cells (MCs). Degranulated MCs release chemotactic and protease factors, such as tryptase and chymase, to the extracellular medium, contributing to the degradation of the extracellular matrix, promoting angiogenesis, providing a favorable environment for tumor invasion and tissue remodeling through selective proteolysis in the matrix and activation of metalloproteinases. Another important aspect of tumor growth is the anti-inflammatory protein Annexin A1 (ANXA1), related to the regulation of growth and migration / invasion processes, and its effects mediated by receptors for formylated peptides (FPRs), especially FPR1 and FPR2. The objective of this investigation was to analyze the heterogeneity of the MCs and the expression of the ANXA1, FPR1 and FPR2 proteins in human biopsies of clinical-pathological variables of normal uterus: simple endometrial hyperplasia (HES), adenomyosis, leiomyomas and endometrial adenocarcinoma (ADC) of grades I and II. MCs were quantified according to their state of activation and expression of tryptase and chymase proteases. Expression of ANXA1 and its FPR1 and FPR2 receptors in the MCs and uterine tissues were analyzed in the different biopsies studied. Our results showed intact and degranulated MCs in the normal endometrium and myometrium and increased MCs in HES, tumor margins in leiomyomas, adenomyosis and endometrial ADC of grades I and II, but significantly decreased in the leiomyoma tumor region. In relation to the heterogeneity, it was observed that the tryptase-positive MCs were observed in greater quantity. Endogenous expressions of ANXA1 and FPR1 were observed in uterine tissues and MCs, but absent for FPR2. Modulations of MCs and ANXA1 protein expression and the specificity of FPR1 receptor immunolabeling in the clinical-pathological variables of the investigated uterine lesions indicate the involvement of these cells and the interaction ANXA1/FPR1 in the development of inflammation and uterine neoplasia.
8

Regulation of leukocyte functions by the formyl peptide receptor 2

Othman, Amira 04 1900 (has links)
Les neutrophiles jouent un rôle central dans la défense de l'hôte contre les infections et les lésions tissulaires. Les neutrophiles intègrent des signaux opposés au sein du microenvironnement inflammatoire, qui convergent vers des récepteurs sélectionnés. Parmi ces récepteurs se trouve le récepteur pléiotrope, le récepteur du formyle peptide 2/récepteur de la lipoxine (FPR2/ALX) qui peut reconnaître plus de 20 ligands protéiques, peptidiques et lipidiques structurellement divers. Parmi ces ligands se trouvent des peptides N-formylés libérés par les mitochondries de cellules hôtes mourantes ou mortes. À l'heure actuelle, on sait peu de choses sur la base moléculaire de la façon dont FPR2/ALX intègre des signaux opposés et déclenche diverses réponses biologiques. Nous avons constaté que le récepteur pléiotrope FPR2/ALX intègre des signaux opposés qui régissent la phagocytose, la destruction bactérienne, le sort des neutrophiles et, finalement, le résultat de la réponse inflammatoire. Cette action des peptides N-formylés est médiée par l'induction de la libération d'élastase neutrophile à partir des granules primaires et la régulation négative subséquente du récepteur C5a du complément à la surface cellulaire, qui peut être inversée par des médiateurs lipidiques pro-résolvants, déclenchée par l'aspirine 15-épi- lipoxine A4 (15-epi-LXA4) et 17-épi-résolvine D1 (17-epi-RvD1). Cela peut contribuer au développement de nouvelles stratégies pharmacologiques visant à améliorer les mécanismes de protection médiés par FPR2/ALX qui peuvent limiter la réponse inflammatoire et favoriser la résolution de l'inflammation. / Neutrophils play a central role in host defense against infection and tissue injury. PMNs integrate opposing cues within the inflammatory microenvironment, which converge on selected receptors. Among these receptors is the pleiotropic receptor, formyl peptide receptor 2/lipoxin receptor (FPR2/ALX), which can recognize over 20 structurally diverse proteins, peptides, and lipid ligands. Among these ligands are N-formylated peptides released from mitochondria of dying or dead host cells. At present, little is known about the molecular basis for how FPR2/ALX integrates opposing cues and triggers diverse biological responses. We wanted to test the effect of N-formylated peptides on human neutrophils' functions in sepsis-like syndrome. We found that the pleiotropic receptor FPR2/ALX integrates opposing signals that govern phagocytosis, bacterial killing, the fate of neutrophils, and ultimately the outcome of the inflammatory response. This action of N-formylated peptides is mediated through induction of the release of neutrophil elastase from the primary granules and subsequent downregulation of complement C5a receptor on the cell surface. This effect can be reversed by pro-resolving lipid mediators, aspirin-triggered 15-epi-lipoxin A4 (15-epi-LXA4) and 17-epi-resolvin D1 (17-epi-RvD1). Our results could lead to the development of novel pharmacological strategies to enhance FPR2/ALX-mediated protective mechanisms that may limit the inflammatory response and promote the resolution of inflammation.
9

Estudo da expressão dos receptores do peptídeo insulinotrópico dependente de glicose (GIPR) e do hormônio luteinizante (LHCGR) em tumores e hiperplasias do córtex adrenal / Expression Study of Glucose-dependent insulinotropic peptide receptor (GIPR) and luteinizing hormone receptor (LHCGR) in adrenocortical tumors and hyperplasia

Costa, Marcia Helena Soares 16 July 2007 (has links)
Introdução: Os receptores do peptídeo insulinotrópico dependente de glicose (GIPR) e do hormônio luteinizante (LHCGR) são receptores acoplados à proteína G com amplo padrão de expressão tecidual. A expressão anômala destes receptores tem sido descrita em casos de hiperplasia adrenal macronodular independente de ACTH (AIMAH) e em alguns adenomas, resultando em aumento da secreção hormonal (cortisol, andrógenos e aldosterona) pelo cortex adrenal. O papel destes receptores em outras formas de hiperplasia, como a doença adrenocortical nodular pigmentosa primária (PPNAD), aumento da adrenal associado à neoplasia endócrina múltipla tipo 1 (MEN1), e em carcinoma do córtex adrenal tem sido pouco investigado; sendo assim, considera-se relevante estudar a expressão destes receptores nos pacientes com tumores adrenocorticais esporádicos, nos pacientes com AIMAH, PPNAD e aumento adrenal associado à MEN1. Objetivos: 1) Caracterização molecular dos casos de neoplasia endócrina múltipla tipo 1 e PPNAD: pesquisa de mutações dos genes MEN1 e PRKAR1A e análise da perda de heterozigose (LOH) destes genes no tecido adrenal destes pacientes. 2) Quantificar a expressão do GIPR e do LHCGR em tecido adrenocortical normal, tumoral, hiperplásico e correlacionar a expressão destes com a classificação histológica dos tumores adrenocorticais. Pacientes: 55 pacientes (30 adultos) com tumores adrenocorticais (37 adenomas e 18 carcinomas); 7 pacientes com AIMAH, 4 com MEN1, 1 com PPNAD e tecidos controles (adrenal; testículo e pâncreas). Métodos: extração de DNA genômico, RNA e síntese de DNA complementar (cDNA); amplificação por PCR das regiões codificadoras dos genes MEN1 e PRKAR1A seguida por seqüenciamento automático. Pesquisa de LOH pela amplificação de microssatélites por PCR e análise pelo programa GeneScan. Quantificação da expressão do GIPR e do LHCGR por PCR em tempo real pelo método TaqMan e estudo de imunohistoquímica para GIPR nos tumores adrenocorticais. Resultados: identificação de 3 mutações (893+ 1G>A, W183X e A68fsX118) e dois polimorfirmos (S145S e D418D) no gene MEN1 e uma mutação (Y21X) no PRKAR1A. Ausência de LOH nos tecidos adrenais estudados. A expressão do GIPR e do LHCGR foi identificada em tecidos adrenais normais, tumorais e hiperplásicos. O nível de expressão do GIPR foi mais elevado nos tumores adrenocorticais malignos que nos benignos tanto no grupo pediátrico (mediana= 18,1 e 4,6, respectivamente; p <0,05), quanto no grupo adulto (mediana = 4,8 e 1,3 respectivamente; p <0,001). O nível de expressão do LHCGR, no grupo pediátrico, foi elevado tanto nos tumores benignos quanto nos malignos (mediana= 6,4 e 4,3, respectivamente). No grupo adulto os níveis de expressão deste receptor foram extremamente baixos nos tumores malignos em relação aos benignos (mediana= 0,06 e 2,3, respectivamente; p <0,001). A imunohistoquímica para o GIPR foi variável e não correlacionada à expressão do gene GIPR. Não houve diferença nos níveis de expressão do GIPR e do LHCGR nas hiperplasias do córtex adrenal. Conclusões: a presença de LOH e mutação em heterozigose composta do gene MEN1 e do PRKAR1A foram afastadas como mecanismos responsáveis pelo aumento adrenal tanto nos pacientes com MEN1 como no paciente com PPNAD. A hiperexpressão de GIPR está associada a malignidade nos tumores adrenocorticais nos grupos adulto e pediátrico e a baixa expressão de LHCGR está associada a malignidade nos tumores adrenocorticais somente no grupo adulto. / Introduction: The glucose- dependent insulinotropic peptide receptor (GIPR) and luteinizing hormone receptor (LHCGR) are G-protein coupled receptors with a wide tissue expression pattern. The aberrant expression of these receptors has been described in cases of ACTH-independent macronodular adrenal hyperplasia (AIMAH) and in some adenomas, resulting in the increase of adrenal cortex hormonal secretion (cortisol, androgens and aldosterone). The role of these receptors in other forms of adrenocortical hyperplasia, such as primary pigmented nodular adrenocortical disease (PPNAD), adrenal enlargement associated with multiple endocrine neoplasia type 1 (MEN1), and adrenocortical carcinoma has been scarcely investigated. Thus, the study of the expression of these receptors in patients with sporadical adrenocortical tumors, AIMAH, PPNAD and adrenal enlargement associated to MEN1 was considered important. Objectives: 1) Molecular study in patients with multiple endocrine neoplasia type 1 and PPNAD: mutation screening of MEN1 and PRKAR1A genes and analysis of the loss of heterozygosis (LOH) of these genes in the adrenal lesions of these patients. 2) To quantify the GIPR and LHCGR expression, in normal, tumor and hyperplasic tissue and to correlate the expression of these receptors with the adrenocortical tumor histology. Patients: 55 patients (30 adults) with adrenocortical tumors (37 adenomas and 18 carcinomas); 7 patients with AIMAH, 4 with MEN1, 1 with PPNAD and control tissue (adrenal, testis and pancreas). Methods: Extraction of genomic DNA, RNA and synthesis of complementary DNA (cDNA); PCR-amplification of the coding regions of MEN1 and PRKAR1A, followed by direct sequencing. LOH study using polymorphic marker amplification by PCR and GeneScan software analysis. Quantification of GIPR and LHCGR expression using realtime PCR -TaqMan method and GIPR immunohistochemistry study in adrenocortical tumors. Results: Identification of 3 mutations (893+ 1G>A, W183X and A68fsX118) and two polymorphic alterations (S145S and D418D) in MEN1 and a mutation (Y21X) in the PRKAR1A gene; LOH was not identified in adrenal tissue. The GIPR and LHCGR expression was identified in normal, tumor and hyperplasic adrenal tissues; the GIPR expression level was more elevated in malignant tumors compared to benign tumors in pediatric (median = 18.1 and 4.6, respectively; p <0.05) and adult patients (median = 4.8 and 1.3 respectively; p <0.001). The LHCGR expression in pediatric patients was elevated in benign as well as in malignant tumors (median = 6.4 and 4.3, respectively). In the adult group, the expression level of these receptors was extremely low in malignant tumors in relation to benign ones (median = 0.06 and 2.3, respectively; p <0.001). The GIPR immunohistochemistry was variable and did not correlate with GIPR gene expression. No difference between GIPR and LHCGR expression levels was observed in the different forms of hyperplasia. Conclusions: The presence of LOH and mutations in compound heterozygosis of MEN1 and PRKAR1A genes were ruled out as the mechanisms responsible for the adrenal enlargement in patients with multiple endocrine neoplasia type 1. GIPR overexpression is associated with malignant adrenocortical tumors in the adult and pediatric patients and low LHCGR expression is associated with malignant adrenocortical tumors only in the adult patients.
10

Estudo da expressão dos receptores do peptídeo insulinotrópico dependente de glicose (GIPR) e do hormônio luteinizante (LHCGR) em tumores e hiperplasias do córtex adrenal / Expression Study of Glucose-dependent insulinotropic peptide receptor (GIPR) and luteinizing hormone receptor (LHCGR) in adrenocortical tumors and hyperplasia

Marcia Helena Soares Costa 16 July 2007 (has links)
Introdução: Os receptores do peptídeo insulinotrópico dependente de glicose (GIPR) e do hormônio luteinizante (LHCGR) são receptores acoplados à proteína G com amplo padrão de expressão tecidual. A expressão anômala destes receptores tem sido descrita em casos de hiperplasia adrenal macronodular independente de ACTH (AIMAH) e em alguns adenomas, resultando em aumento da secreção hormonal (cortisol, andrógenos e aldosterona) pelo cortex adrenal. O papel destes receptores em outras formas de hiperplasia, como a doença adrenocortical nodular pigmentosa primária (PPNAD), aumento da adrenal associado à neoplasia endócrina múltipla tipo 1 (MEN1), e em carcinoma do córtex adrenal tem sido pouco investigado; sendo assim, considera-se relevante estudar a expressão destes receptores nos pacientes com tumores adrenocorticais esporádicos, nos pacientes com AIMAH, PPNAD e aumento adrenal associado à MEN1. Objetivos: 1) Caracterização molecular dos casos de neoplasia endócrina múltipla tipo 1 e PPNAD: pesquisa de mutações dos genes MEN1 e PRKAR1A e análise da perda de heterozigose (LOH) destes genes no tecido adrenal destes pacientes. 2) Quantificar a expressão do GIPR e do LHCGR em tecido adrenocortical normal, tumoral, hiperplásico e correlacionar a expressão destes com a classificação histológica dos tumores adrenocorticais. Pacientes: 55 pacientes (30 adultos) com tumores adrenocorticais (37 adenomas e 18 carcinomas); 7 pacientes com AIMAH, 4 com MEN1, 1 com PPNAD e tecidos controles (adrenal; testículo e pâncreas). Métodos: extração de DNA genômico, RNA e síntese de DNA complementar (cDNA); amplificação por PCR das regiões codificadoras dos genes MEN1 e PRKAR1A seguida por seqüenciamento automático. Pesquisa de LOH pela amplificação de microssatélites por PCR e análise pelo programa GeneScan. Quantificação da expressão do GIPR e do LHCGR por PCR em tempo real pelo método TaqMan e estudo de imunohistoquímica para GIPR nos tumores adrenocorticais. Resultados: identificação de 3 mutações (893+ 1G>A, W183X e A68fsX118) e dois polimorfirmos (S145S e D418D) no gene MEN1 e uma mutação (Y21X) no PRKAR1A. Ausência de LOH nos tecidos adrenais estudados. A expressão do GIPR e do LHCGR foi identificada em tecidos adrenais normais, tumorais e hiperplásicos. O nível de expressão do GIPR foi mais elevado nos tumores adrenocorticais malignos que nos benignos tanto no grupo pediátrico (mediana= 18,1 e 4,6, respectivamente; p <0,05), quanto no grupo adulto (mediana = 4,8 e 1,3 respectivamente; p <0,001). O nível de expressão do LHCGR, no grupo pediátrico, foi elevado tanto nos tumores benignos quanto nos malignos (mediana= 6,4 e 4,3, respectivamente). No grupo adulto os níveis de expressão deste receptor foram extremamente baixos nos tumores malignos em relação aos benignos (mediana= 0,06 e 2,3, respectivamente; p <0,001). A imunohistoquímica para o GIPR foi variável e não correlacionada à expressão do gene GIPR. Não houve diferença nos níveis de expressão do GIPR e do LHCGR nas hiperplasias do córtex adrenal. Conclusões: a presença de LOH e mutação em heterozigose composta do gene MEN1 e do PRKAR1A foram afastadas como mecanismos responsáveis pelo aumento adrenal tanto nos pacientes com MEN1 como no paciente com PPNAD. A hiperexpressão de GIPR está associada a malignidade nos tumores adrenocorticais nos grupos adulto e pediátrico e a baixa expressão de LHCGR está associada a malignidade nos tumores adrenocorticais somente no grupo adulto. / Introduction: The glucose- dependent insulinotropic peptide receptor (GIPR) and luteinizing hormone receptor (LHCGR) are G-protein coupled receptors with a wide tissue expression pattern. The aberrant expression of these receptors has been described in cases of ACTH-independent macronodular adrenal hyperplasia (AIMAH) and in some adenomas, resulting in the increase of adrenal cortex hormonal secretion (cortisol, androgens and aldosterone). The role of these receptors in other forms of adrenocortical hyperplasia, such as primary pigmented nodular adrenocortical disease (PPNAD), adrenal enlargement associated with multiple endocrine neoplasia type 1 (MEN1), and adrenocortical carcinoma has been scarcely investigated. Thus, the study of the expression of these receptors in patients with sporadical adrenocortical tumors, AIMAH, PPNAD and adrenal enlargement associated to MEN1 was considered important. Objectives: 1) Molecular study in patients with multiple endocrine neoplasia type 1 and PPNAD: mutation screening of MEN1 and PRKAR1A genes and analysis of the loss of heterozygosis (LOH) of these genes in the adrenal lesions of these patients. 2) To quantify the GIPR and LHCGR expression, in normal, tumor and hyperplasic tissue and to correlate the expression of these receptors with the adrenocortical tumor histology. Patients: 55 patients (30 adults) with adrenocortical tumors (37 adenomas and 18 carcinomas); 7 patients with AIMAH, 4 with MEN1, 1 with PPNAD and control tissue (adrenal, testis and pancreas). Methods: Extraction of genomic DNA, RNA and synthesis of complementary DNA (cDNA); PCR-amplification of the coding regions of MEN1 and PRKAR1A, followed by direct sequencing. LOH study using polymorphic marker amplification by PCR and GeneScan software analysis. Quantification of GIPR and LHCGR expression using realtime PCR -TaqMan method and GIPR immunohistochemistry study in adrenocortical tumors. Results: Identification of 3 mutations (893+ 1G>A, W183X and A68fsX118) and two polymorphic alterations (S145S and D418D) in MEN1 and a mutation (Y21X) in the PRKAR1A gene; LOH was not identified in adrenal tissue. The GIPR and LHCGR expression was identified in normal, tumor and hyperplasic adrenal tissues; the GIPR expression level was more elevated in malignant tumors compared to benign tumors in pediatric (median = 18.1 and 4.6, respectively; p <0.05) and adult patients (median = 4.8 and 1.3 respectively; p <0.001). The LHCGR expression in pediatric patients was elevated in benign as well as in malignant tumors (median = 6.4 and 4.3, respectively). In the adult group, the expression level of these receptors was extremely low in malignant tumors in relation to benign ones (median = 0.06 and 2.3, respectively; p <0.001). The GIPR immunohistochemistry was variable and did not correlate with GIPR gene expression. No difference between GIPR and LHCGR expression levels was observed in the different forms of hyperplasia. Conclusions: The presence of LOH and mutations in compound heterozygosis of MEN1 and PRKAR1A genes were ruled out as the mechanisms responsible for the adrenal enlargement in patients with multiple endocrine neoplasia type 1. GIPR overexpression is associated with malignant adrenocortical tumors in the adult and pediatric patients and low LHCGR expression is associated with malignant adrenocortical tumors only in the adult patients.

Page generated in 0.0656 seconds