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1.
Article in English | MEDLINE | ID: mdl-26347711

ABSTRACT

Pheochromocytomas (PCCs) and paragangliomas (PGLs) are neuroendocrine tumors derived from the chromaffin tissue. Diagnosis of these tumors is extremely important as they are linked to the hypertension syndrome with great cardiovascular morbidity and mortality. A great majority of PCCs and PGLs are sporadic and benign tumors; however, the classic idea of 10% exception of these features is changing. The description of new genes linked to familial forms of PCC/PGLs, such as succinate dehydrogenase (SDH) complex subunits, KIF1Bß, EGLN1, TMEM127, and MAX, added to the well-known PCC familial syndrome (MEN2, VHL, and neurofibromatosis type 1) presents new challenges for diagnosis. In this review, we discuss the diversity of clinical and genetic approaches to this syndrome as well the diverse criteria that should guide genetic investigation.

2.
Clinics (Sao Paulo) ; 66(4): 529-33, 2011.
Article in English | MEDLINE | ID: mdl-21655742

ABSTRACT

BACKGROUND: The molecular mechanisms involved in the genesis of the adrenocortical lesions seen in MEN1 syndrome (ACL-MEN1) remain poorly understood; loss of heterozygosity at 11q13 and somatic mutations of MEN1 are not usually found in these lesions. Thus, additional genes must be involved in MEN1 adrenocortical disorders. Overexpression of the glucose-dependent insulinotropic peptide receptor has been shown to promote adrenocortical tumorigenesis in a mice model and has also been associated with ACTH-independent Cushing syndrome in humans. However, to our knowledge, the status of glucose-dependent insulinotropic peptide receptor expression in adrenocortical lesions in MEN1 has not been previously investigated. OBJECTIVE: To evaluate glucose-dependent insulinotropic peptide receptor expression in adrenocortical hyperplasia associated with MEN1 syndrome. MATERIALS/METHODS: Three adrenocortical tissue samples were obtained from patients with previously known MEN1 germline mutations and in whom the presence of a second molecular event (a new MEN1 somatic mutation or an 11q13 loss of heterozygosity) had been excluded. The expression of the glucose-dependent insulinotropic peptide receptor was quantified by qPCR using the DDCT method, and b-actin was used as an endogenous control. RESULTS: The median of glucose-dependent insulinotropic peptide receptor expression in the adrenocortical lesions associated with MEN1 syndrome was 2.6-fold (range 1.2 to 4.8) higher than the normal adrenal controls (p = 0.02). CONCLUSION: The current study represents the first investigation of glucose-dependent insulinotropic peptide receptor expression in adrenocortical lesions without 11q13 loss of heterozygosity in MEN1 syndrome patients. Although we studied a limited number of cases of MEN1 adrenocortical lesions retrospectively, our preliminary data suggest an involvement of glucose-dependent insulinotropic peptide receptor overexpression in the etiology of adrenocortical hyperplasia. New prospective studies will be able to clarify the exact role of the glucose-dependent insulinotropic peptide receptor in the molecular pathogenesis of MEN1 adrenocortical lesions.


Subject(s)
Adrenal Gland Neoplasms/metabolism , Adrenal Glands/pathology , Chromosomes, Human, Pair 11/genetics , Loss of Heterozygosity/genetics , Multiple Endocrine Neoplasia Type 1/metabolism , Receptors, Gastrointestinal Hormone/metabolism , Adrenal Gland Neoplasms/genetics , Adrenal Glands/metabolism , Adult , Aged , Case-Control Studies , Female , Humans , Hyperplasia/metabolism , Hyperplasia/pathology , Male , Middle Aged , Multiple Endocrine Neoplasia Type 1/genetics , Receptors, Gastrointestinal Hormone/genetics , Statistics, Nonparametric
3.
Clinics ; 66(4): 529-533, 2011. ilus, tab
Article in English | LILACS | ID: lil-588899

ABSTRACT

BACKGROUND: The molecular mechanisms involved in the genesis of the adrenocortical lesions seen in MEN1 syndrome (ACL-MEN1) remain poorly understood; loss of heterozygosity at 11q13 and somatic mutations of MEN1 are not usually found in these lesions. Thus, additional genes must be involved in MEN1 adrenocortical disorders. Overexpression of the glucose-dependent insulinotropic peptide receptor has been shown to promote adrenocortical tumorigenesis in a mice model and has also been associated with ACTH-independent Cushing syndrome in humans. However, to our knowledge, the status of glucose-dependent insulinotropic peptide receptor expression in adrenocortical lesions in MEN1 has not been previously investigated. OBJECTIVE: To evaluate glucose-dependent insulinotropic peptide receptor expression in adrenocortical hyperplasia associated with MEN1 syndrome. MATERIALS/METHODS: Three adrenocortical tissue samples were obtained from patients with previously known MEN1 germline mutations and in whom the presence of a second molecular event (a new MEN1 somatic mutation or an 11q13 loss of heterozygosity) had been excluded. The expression of the glucose-dependent insulinotropic peptide receptor was quantified by qPCR using the DDCT method, and b-actin was used as an endogenous control. RESULTS: The median of glucose-dependent insulinotropic peptide receptor expression in the adrenocortical lesions associated with MEN1 syndrome was 2.6-fold (range 1.2 to 4.8) higher than the normal adrenal controls (p = 0.02). CONCLUSION: The current study represents the first investigation of glucose-dependent insulinotropic peptide receptor expression in adrenocortical lesions without 11q13 loss of heterozygosity in MEN1 syndrome patients. Although we studied a limited number of cases of MEN1 adrenocortical lesions retrospectively, our preliminary data suggest an involvement of glucose-dependent insulinotropic peptide receptor overexpression in the etiology of adrenocortical hyperplasia. New prospective studies will be able to clarify the exact role of the glucose-dependent insulinotropic peptide receptor in the molecular pathogenesis of MEN1 adrenocortical lesions.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Adrenal Gland Neoplasms/metabolism , Adrenal Glands/pathology , /genetics , Loss of Heterozygosity/genetics , Multiple Endocrine Neoplasia Type 1/metabolism , Receptors, Gastrointestinal Hormone/metabolism , Adrenal Gland Neoplasms/genetics , Adrenal Glands/metabolism , Case-Control Studies , Hyperplasia/metabolism , Hyperplasia/pathology , Multiple Endocrine Neoplasia Type 1/genetics , Receptors, Gastrointestinal Hormone/genetics , Statistics, Nonparametric
4.
Arq Bras Endocrinol Metabol ; 53(3): 326-31, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19578593

ABSTRACT

OBJECTIVE: To analyze the aberrant expression of the GIPR and LHCGR in different forms of adrenocortical hyperplasia: ACTH-independent macronodular adrenal hyperplasia (AIMAH), primary pigmented nodular adrenocortical disease (PPNAD) and diffuse adrenal hyperplasia secondary to Cushing's disease (DAHCD). METHODS: We quantified GIPR and LHCGR expressions using real time PCR in 20 patients with adrenocortical hyperplasia (seven with AIMAH, five with PPNAD, and eight with DAHCD). Normal adrenals tissues were used as control and the relative expression was compared with beta-actin. RESULTS: GIPR and LHCGR expressions were demonstrated in all tissues studied. Median GIPR and LHCGR mRNA levels were 1.6; 0.4; 0.5 and 1.3; 0.9; 1.0 in adrenocortical tissues from AIMAH, PPNAD and DAHCD respectively. There were no differences between GIPR and LHCGR expressions in all tissues studied. CONCLUSIONS: GIPR and LHCGR overexpression were not identified in the studied cases, thus suggesting that this molecular mechanism is not involved in adrenocortical hyperplasia in our patients.


Subject(s)
Adrenal Cortex Diseases/metabolism , Adrenal Glands/pathology , Pituitary ACTH Hypersecretion/metabolism , Receptors, Gastrointestinal Hormone/metabolism , Receptors, LH/metabolism , Actins/metabolism , Adolescent , Adrenal Cortex Diseases/genetics , Adrenal Glands/metabolism , Adult , Aged , Female , Humans , Hyperplasia/metabolism , Male , Middle Aged , Pituitary ACTH Hypersecretion/genetics , Polymerase Chain Reaction , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Gastrointestinal Hormone/genetics , Receptors, LH/genetics , Reverse Transcriptase Polymerase Chain Reaction , Young Adult
5.
Arq. bras. endocrinol. metab ; 53(3): 326-331, Apr. 2009. graf, tab
Article in English | LILACS | ID: lil-517675

ABSTRACT

OBJECTIVE: To analyze the aberrant expression of the GIPR and LHCGR in different forms of adrenocortical hyperplasia: ACTH-independent macronodular adrenal hyperplasia (AIMAH), primary pigmented nodular adrenocortical disease (PPNAD) and diffuse adrenal hyperplasia secondary to Cushing's disease (DAHCD). METHODS: We quantified GIPR and LHCGR expressions using real time PCR in 20 patients with adrenocortical hyperplasia (seven with AIMAH, five with PPNAD, and eight with DAHCD). Normal adrenals tissues were used as control and the relative expression was compared with β-actin. RESULTS: GIPR and LHCGR expressions were demonstrated in all tissues studied. Median GIPR and LHCGR mRNA levels were 1.6; 0.4; 0.5 and 1.3; 0.9; 1.0 in adrenocortical tissues from AIMAH, PPNAD and DAHCD respectively. There were no differences between GIPR and LHCGR expressions in all tissues studied. CONCLUSIONS: GIPR and LHCGR overexpression were not identified in the studied cases, thus suggesting that this molecular mechanism is not involved in adrenocortical hyperplasia in our patients.


OBJETIVO: Analisar a expressão aberrante do GIPR e do LHCGR em diferentes formas de hiperplasias adrenocorticais: hiperplasia adrenal macronodular independente de ACTH (AIMAH), doença adrenocortical nodular pigmentada primária (PPNAD) e hiperplasia adrenal difusa secundária à doença de Cushing (DAHCD). MÉTODOS: Quantificou-se por PCR em tempo real a expressão desses receptores em 20 pacientes: sete com AIMAH, cinco com PPNAD e oito com DAHCD. Adrenais normais foram utilizadas como controle e a expressão relativa desses receptores foi comparada à expressão da β-actina. RESULTADOS: A expressão desses receptores foi demonstrada em todos os tecidos estudados. A mediana da expressão do GIPR e do LHCGR foi de 1,6; 0,4; 0,5 e de 1,3; 0,9; 1,0 nos tecidos dos pacientes com AIMAH, PPNAD e DAHCD, respectivamente. Não houve diferença significativa na expressão desses receptores nos tecidos estudados. CONCLUSÕES: Hiperexpressão do GIPR e do LHCGR não foi observada, sugerindo que esse mecanismo não está envolvido na patogênese molecular da hiperplasia adrenal nesses pacientes.


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Adrenal Cortex Diseases/metabolism , Adrenal Glands/pathology , Pituitary ACTH Hypersecretion/metabolism , Receptors, Gastrointestinal Hormone/metabolism , Receptors, LH/metabolism , Actins/metabolism , Adrenal Cortex Diseases/genetics , Adrenal Glands/metabolism , Hyperplasia/metabolism , Polymerase Chain Reaction , Pituitary ACTH Hypersecretion/genetics , Reverse Transcriptase Polymerase Chain Reaction , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Gastrointestinal Hormone/genetics , Receptors, LH/genetics , Young Adult
6.
J Endocrinol ; 200(2): 167-75, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18971217

ABSTRACT

Glucose-dependent insulinotropic peptide receptor (GIPR) and LHCGR are G-protein-coupled receptors with a wide tissue expression pattern. Aberrant expression of these receptors has rarely been demonstrated in adult sporadic adrenocortical tumors with a lack of data on pediatric tumors. We quantified the GIPR and LHCGR expression in a large cohort of 55 patients (25 children and 30 adults) with functioning and non-functioning sporadic adrenocortical tumors. Thirty-eight tumors were classified as adenomas whereas 17 were carcinomas. GIPR and LHCGR expression were analyzed by real-time PCR and normal human pancreatic and testicular tissue samples were used as positive controls. Mean expression values were determined by fold increase in comparison with a normal adrenal pool. GIPR mRNA levels were significantly higher in adrenocortical carcinomas than in adenomas from both pediatric and adult groups. LHCGR expression was similar in both carcinomas and adenomas from the pediatric group but significantly lower in carcinomas than in adenomas from the adult group (median 0.06 and 2.3 respectively, P<0.001). GIPR was detected by immunohistochemistry in both pediatric and adult tumors. Staining and real-time PCR results correlated positively only when GIPR mRNA levels were increased at least two-fold in comparison with normal adrenal expression levels. In conclusion, GIPR overexpression was observed in pediatric and adult adrenocortical tumors and very low levels of LHCGR expression were found in all adult adrenocortical carcinomas.


Subject(s)
Adrenal Cortex Neoplasms/genetics , Adrenocortical Adenoma/genetics , Adrenocortical Carcinoma/genetics , Gene Expression Regulation, Neoplastic/genetics , Receptors, Gastrointestinal Hormone/genetics , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Gene Expression , Humans , Infant , Male , Middle Aged , Receptors, LH/genetics , Reverse Transcriptase Polymerase Chain Reaction
7.
Arq. bras. endocrinol. metab ; 52(8): 1257-1263, Nov. 2008. ilus, tab
Article in English | LILACS | ID: lil-503291

ABSTRACT

OBJECTIVE: Primary pigmented nodular adrenocortical disease (PPNAD) is the main endocrine manifestation of Carney complex, a multiple neoplasia syndrome caused by PRKAR1A gene mutations. The presence of PRKAR1A loss of heterozygosity (LOH) in adrenocortical tumorigenesis remains controversial. The aim of the present study is to investigate the presence of PRKAR1A LOH in adrenocortical cells in a patient with Carney complex. METHODS: The LOH was investigated using a PRKAR1A informative intragenic marker by GeneScan software analysis in DNA obtained from laser-captured microdissected cells of several adrenal nodules. Patients: A young adult male patient with Carney complex and his family were studied. RESULTS: A novel heterozygous mutation (p. Y21X) was identified at PRKAR1A in blood DNA of the male proband and his relatives. No PRKAR1A LOH was evidenced in the laser-captured microdissected cells from PPNAD tissue by different methodologies. CONCLUSION: We identified a new PRKAR1A nonsense mutation and in addition we did not evidence PRKAR1A LOH in laser-captured nodules cells, suggesting that adrenocortical tumorigenesis in PPNAD may occurs apart from the second hit.


OBJETIVO: A doença adrenocortical nodular pigmentosa primária (PPNAD) é uma das manifestações do complexo de Carney, uma neoplasia endócrina múltipla causada por mutações no PRKAR1A. A perda de heterozigose (LOH) do PRKAR1A na tumorigenese adrenal permanece controversa dada à possibilidade de contaminação com o tecido normal. Nosso objetivo foi investigar a presença de LOH no PRKAR1A a partir de células do nódulo adrenal de um paciente com complexo de Carney. MÉTODOS: A pesquisa da LOH do PRKAR1A foi realizada através do estudo de um marcador intragênico em DNA de células do nódulo adrenal microdissecadas a laser, evitando contaminação com o tecido normal. Pacientes: Um paciente com PPNAD e cinco familiares foram estudados. RESULTADOS: A nova mutação (p. Y21X) foi identificada no PRKAR1A sem evidência de LOH no tecido adrenal. CONCLUSÃO: Identificamos uma nova mutação no PRKAR1A e não evidenciamos LOH nas células dos nódulos adrenocorticais, sugerindo que a PPNAD possa ocorrer na ausência de um segundo evento molecular.


Subject(s)
Adolescent , Female , Humans , Male , Middle Aged , Adrenal Cortex/pathology , Codon, Nonsense/genetics , Cyclic AMP-Dependent Protein Kinase RIalpha Subunit/genetics , Loss of Heterozygosity , Multiple Endocrine Neoplasia/genetics , Adrenal Cortex/cytology , Codon, Nonsense/blood , Lasers , Pedigree
8.
J Clin Endocrinol Metab ; 93(9): 3524-31, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18611974

ABSTRACT

BACKGROUND: Adrenocortical tumors are heterogeneous neoplasms with incompletely understood pathogenesis. IGF-II overexpression has been consistently demonstrated in adult adrenocortical carcinomas. OBJECTIVES: The objective of the study was to analyze expression of IGF-II and its receptor (IGF-IR) in pediatric and adult adrenocortical tumors and the effects of a selective IGF-IR kinase inhibitor (NVP-AEW541) on adrenocortical tumor cells. PATIENTS: Fifty-seven adrenocortical tumors (37 adenomas and 20 carcinomas) from 23 children and 34 adults were studied. METHODS: Gene expression was determined by quantitative real-time PCR. Cell proliferation and apoptosis were analyzed in NCI H295 cells and a new cell line established from a pediatric adrenocortical adenoma. RESULTS: IGF-II transcripts were overexpressed in both pediatric adrenocortical carcinomas and adenomas. Otherwise, IGF-II was mainly overexpressed in adult adrenocortical carcinomas (270.5 +/- 130.2 vs. 16.1 +/- 13.3; P = 0.0001). IGF-IR expression was significantly higher in pediatric adrenocortical carcinomas than adenomas (9.1 +/- 3.1 vs. 2.6 +/- 0.3; P = 0.0001), whereas its expression was similar in adult adrenocortical carcinomas and adenomas. IGF-IR expression was a predictor of metastases in pediatric adrenocortical tumors in univariate analysis (hazard ratio 1.84; 95% confidence interval 1.28-2.66; P = 0.01). Furthermore, NVP-AEW541 blocked cell proliferation in a dose- and time-dependent manner in both cell lines through a significant increase of apoptosis. CONCLUSION: IGF-IR overexpression was a biomarker of pediatric adrenocortical carcinomas. Additionally, a selective IGF-IR kinase inhibitor had antitumor effects in adult and pediatric adrenocortical tumor cell lines, suggesting that IGF-IR inhibitors represent a promising therapy for human adrenocortical carcinoma.


Subject(s)
Adenoma/genetics , Adrenal Cortex Neoplasms/genetics , Carcinoma/genetics , Insulin-Like Growth Factor II/genetics , Receptor, IGF Type 2/genetics , Adenoma/pathology , Adolescent , Adrenal Cortex Neoplasms/pathology , Adult , Aged , Carcinoma/pathology , Child , Child, Preschool , Female , Gene Expression Regulation, Neoplastic , Humans , Infant , Insulin-Like Growth Factor II/metabolism , Male , Middle Aged , Neoplasm Metastasis , Receptor, IGF Type 2/metabolism , Tumor Cells, Cultured
9.
Arq Bras Endocrinol Metabol ; 52(8): 1257-63, 2008 Nov.
Article in Portuguese | MEDLINE | ID: mdl-19169478

ABSTRACT

OBJECTIVE: Primary pigmented nodular adrenocortical disease (PPNAD) is the main endocrine manifestation of Carney complex, a multiple neoplasia syndrome caused by PRKAR1A gene mutations. The presence of PRKAR1A loss of heterozygosity (LOH) in adrenocortical tumorigenesis remains controversial. The aim of the present study is to investigate the presence of PRKAR1A LOH in adrenocortical cells in a patient with Carney complex. METHODS: The LOH was investigated using a PRKAR1A informative intragenic marker by GeneScan software analysis in DNA obtained from laser-captured microdissected cells of several adrenal nodules. PATIENTS: A young adult male patient with Carney complex and his family were studied. RESULTS: A novel heterozygous mutation (p. Y21X) was identified at PRKAR1A in blood DNA of the male proband and his relatives. No PRKAR1A LOH was evidenced in the laser-captured microdissected cells from PPNAD tissue by different methodologies. CONCLUSION: We identified a new PRKAR1A nonsense mutation and in addition we did not evidence PRKAR1A LOH in laser-captured nodules cells, suggesting that adrenocortical tumorigenesis in PPNAD may occurs apart from the second hit.


Subject(s)
Adrenal Cortex/pathology , Codon, Nonsense/genetics , Cyclic AMP-Dependent Protein Kinase RIalpha Subunit/genetics , Loss of Heterozygosity , Multiple Endocrine Neoplasia/genetics , Adolescent , Adrenal Cortex/cytology , Codon, Nonsense/blood , Female , Humans , Lasers , Male , Middle Aged , Pedigree
10.
Arq. bras. endocrinol. metab ; 51(8): 1226-1237, nov. 2007. ilus
Article in English | LILACS | ID: lil-471738

ABSTRACT

ACTH-Independent macronodular adrenal hyperplasia (AIMAH) is a rare cause of endogenous Cushing's syndrome (CS), in which clinical features usually become apparent only after several decades of life. This form of adrenal hyperplasia typically produces excess cortisol with overt or subclinical CS, but concurrent secretion of mineralocorticoids or sexual steroids can also occur. The diagnosis is suspected by bilateral adrenal nodules larger than 1 cm on incidental imaging studies or following the demonstration of ACTH-independent hormonal hypersecretion. The pathophysiology of this entity is heterogeneous and has been intensely explored in recent years. Several G-protein coupled receptors aberrantly expressed in the adrenal cortex have been implicated in the regulation of steroidogenesis and in the initial cell proliferation in AIMAH. Several familial cases of AIMAH have been recently described with the same pattern of aberrant hormone receptors in all affected members of the family. It is probable that additional somatic genetic events related to cell cycle regulation, adhesion and transcription factors occur in addition over time in the various nodules; other mechanisms, as Gsp or ACTH receptor mutations and paracrine adrenal hormonal secretion have been rarely identified as the molecular mechanism in some cases. When systematically screened, most patients with AIMAH exhibit an in vivo aberrant cortisol response to one or various ligands suggesting the presence of aberrant adrenal receptors. The identification of these receptors creates the possibility of a specific pharmacological treatment isolated or associated with adrenalectomy.


A hiperplasia adrenal macronodular independente de ACTH (AIMAH) é uma causa rara de síndrome de Cushing (SC) endógena, na qual alguns aspectos clínicos só se tornam evidentes depois de várias décadas de vida. Esta forma de hiperplasia adrenal caracteristicamente produz excesso de cortisol resultando na síndrome de Cushing franca ou subclínica, embora a secreção concomitante de mineralocorticóide, estrógeno e andrógenos também possa ocorrer. A suspeita diagnóstica é feita pela presença de nódulos adrenais bilaterais maiores que 1 cm, como achado incidental em exames de imagem ou pela demonstração de hipersecreção hormonal independente de ACTH. A fisiopatologia desta doença é heterogênea e tem sido intensamente estudada nos últimos anos. Vários receptores acoplados à proteína G, com expressão aberrante no córtex adrenal, têm sido implicados na regulação da esteroidogênese e no início da proliferação celular que ocorre na AIMAH. Diversos casos familiais de AIMAH foram recentemente descritos, e um mesmo padrão de expressão anormal dos receptores aberrantes foi observado em todos os membros afetados das famílias investigadas. Ao longo do tempo, é provável que ocorram, nos nódulos, eventos genéticos adicionais relacionados à regulação do ciclo celular, adesão e fatores de transcrição. Outros mecanismos moleculares, como mutações nos genes da proteína Gsa e do receptor de ACTH, ou secreção hormonal parácrina na adrenal, têm sido raramente identificados em alguns casos. A maioria dos pacientes com AIMAH, quando sistematicamente investigados, desenvolve uma produção anormal de cortisol em resposta a vários ligantes, sugerindo a presença de receptores adrenais aberrantes. A identificação destes receptores cria a possibilidade para um tratamento farmacológico específico isolado ou associado à adrenalectomia.


Subject(s)
Humans , Adrenal Glands/pathology , Cushing Syndrome/etiology , Adrenal Glands/metabolism , Adrenal Glands , Adrenocorticotropic Hormone , GTP-Binding Proteins/physiology , Hydrocortisone , Hyperplasia/complications , Hyperplasia/diagnosis , Hyperplasia/metabolism , Receptors, Gastrointestinal Hormone/physiology , Receptors, Vasopressin/physiology
11.
Curr Opin Endocrinol Diabetes Obes ; 14(3): 219-25, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17940443

ABSTRACT

PURPOSE OF REVIEW: Endogenous Cushing's syndrome is adrenocorticotropic hormone (or corticotropin)-independent in 15-20% of cases. Primary Cushing's syndrome is most often secondary to adrenocortical adenomas or carcinomas, and more rarely to bilateral adrenal hyperplasias. Corticotropin-independent cortisol-producing hyperplasia is caused by micronodular diseases, including primary pigmented nodular adrenocortical disease and nonpigmented micronodular hyperplasia and adrenocorticotropic hormone-independent macronodular adrenal hyperplasia. Primary pigmented nodular adrenocortical disease can be found either alone or in the context of Carney complex, a multiple endocrine neoplasia syndrome. RECENT FINDINGS: In recent years, the pathophysiology of adrenocortical tumors and hyperplasias became better understood following the identification of genes responsible for syndromes associated with corticotropin-independent Cushing's syndrome and the demonstration of aberrant expression and function of various hormone receptors in adrenocortical adenomas and adrenocorticotropic hormone-independent macronodular adrenal hyperplasia. This article reviews findings on the molecular and genetic aspects of corticotropin-independent Cushing's syndrome including recent gene expression profiling studies of adrenocortical tumors and hyperplasias and animal models that provided clues on the pathogenesis of primary Cushing's syndrome. SUMMARY: A better understanding of molecular mechanisms involved in adrenocortical tumors and hyperplasias may lead to improved diagnostic and prognostic markers and treatment strategies to assist clinicians in the management of corticotropin-independent Cushing's syndrome.


Subject(s)
Adrenal Cortex Diseases/complications , Adrenal Cortex Neoplasms/complications , Adrenocorticotropic Hormone/metabolism , Cushing Syndrome/etiology , Adrenal Cortex Diseases/genetics , Adrenal Cortex Diseases/metabolism , Adrenal Cortex Diseases/pathology , Adrenal Cortex Neoplasms/genetics , Adrenal Cortex Neoplasms/metabolism , Animals , Gene Expression Profiling , Humans , Hyperplasia
12.
Arq Bras Endocrinol Metabol ; 51(1): 116-24, 2007 Feb.
Article in Portuguese | MEDLINE | ID: mdl-17435865

ABSTRACT

The aim of this article is to present and discuss several aspects of the pathogenesis, the clinical, hormonal, and imaging diagnosis, and the treatment of Nelson's syndrome, based on a typical patient's report, in whom several therapeutic approaches were shown to be ineffective.


Subject(s)
Adrenalectomy/adverse effects , Brachytherapy , Cushing Syndrome/surgery , Nelson Syndrome/therapy , Adult , Humans , Iodine Radioisotopes/therapeutic use , Magnetic Resonance Spectroscopy , Male , Nelson Syndrome/etiology , Nelson Syndrome/prevention & control
13.
Arq. bras. endocrinol. metab ; 51(1): 116-124, fev. 2007. ilus
Article in Portuguese | LILACS | ID: lil-448373

ABSTRACT

O objetivo deste artigo é apresentar e discutir alguns aspectos da patogênese, do diagnóstico clínico, hormonal e radiológico e do tratamento da síndrome de Nelson, com base no relato de um paciente típico portador da doença, no qual várias abordagens terapêuticas mostraram-se ineficazes.


The aim of this article is to present and discuss several aspects of the pathogenesis, the clinical, hormonal, and imaging diagnosis, and the treatment of Nelson's syndrome, based on a typical patient's report, in whom several therapeutic approaches were shown to be ineffective.


Subject(s)
Adult , Humans , Male , Adrenalectomy/adverse effects , Brachytherapy , Cushing Syndrome/surgery , Nelson Syndrome/therapy , Iodine Radioisotopes/therapeutic use , Magnetic Resonance Spectroscopy , Nelson Syndrome/etiology , Nelson Syndrome/prevention & control
14.
Arq Bras Endocrinol Metabol ; 51(8): 1226-37, 2007 Nov.
Article in English | MEDLINE | ID: mdl-18209860

ABSTRACT

ACTH-Independent macronodular adrenal hyperplasia (AIMAH) is a rare cause of endogenous Cushing's syndrome (CS), in which clinical features usually become apparent only after several decades of life. This form of adrenal hyperplasia typically produces excess cortisol with overt or subclinical CS, but concurrent secretion of mineralocorticoids or sexual steroids can also occur. The diagnosis is suspected by bilateral adrenal nodules larger than 1 cm on incidental imaging studies or following the demonstration of ACTH-independent hormonal hypersecretion. The pathophysiology of this entity is heterogeneous and has been intensely explored in recent years. Several G-protein coupled receptors aberrantly expressed in the adrenal cortex have been implicated in the regulation of steroidogenesis and in the initial cell proliferation in AIMAH. Several familial cases of AIMAH have been recently described with the same pattern of aberrant hormone receptors in all affected members of the family. It is probable that additional somatic genetic events related to cell cycle regulation, adhesion and transcription factors occur in addition over time in the various nodules; other mechanisms, as Gsp or ACTH receptor mutations and paracrine adrenal hormonal secretion have been rarely identified as the molecular mechanism in some cases. When systematically screened, most patients with AIMAH exhibit an in vivo aberrant cortisol response to one or various ligands suggesting the presence of aberrant adrenal receptors. The identification of these receptors creates the possibility of a specific pharmacological treatment isolated or associated with adrenalectomy.


Subject(s)
Adrenal Glands/pathology , Cushing Syndrome/etiology , Adrenal Glands/diagnostic imaging , Adrenal Glands/metabolism , Adrenocorticotropic Hormone/metabolism , GTP-Binding Proteins/physiology , Humans , Hydrocortisone/metabolism , Hyperplasia/complications , Hyperplasia/diagnosis , Hyperplasia/metabolism , Radiography , Receptors, Gastrointestinal Hormone/physiology , Receptors, Vasopressin/physiology
15.
São Paulo; s.n; 2007. 122 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: lil-461235

ABSTRACT

O objetivo deste estudo foi quantificar por PCR em tempo real a expressão dos genes dos receptores do peptídeo insulinotrópico dependente de glicose (GIPR) e do hormônio luteinizante (LHCGR) em tumores e hiperplasias adrenocorticais (hiperplasia adrenal macronodular independente de ACTH; doença nodular adrenocortical pigmentosa primária e aumento da adrenal associado à neoplasia endócrina múltipla tipo 1). O nível de expressão do GIPR foi mais elevado nos tumores malignos que nos benignos em pacientes adultos e pediátricos, enquanto o nível de expressão do LHCGR foi extremamente baixo nos tumores malignos em pacientes adultos. Não se observou diferença no nível de expressão de ambos os receptores nas diferentes formas de hiperplasia.


The aim of this study was to quantify by real-time PCR the gene expression of glucose-dependent insulinotropic peptide receptor (GIPR) and luteinizing hormone receptor (LHCGR) in adrenocortical tumors and hyperplasia (ACTH-independent macronodular adrenal hyperplasia, primary pigmented nodular adrenocortical disease and adrenal enlargement associated with multiple endocrine neoplasia type 1. The GIPR expression level was more elevated in the malignant tumors that in the benign ones, of both adult and pediatric patients, whereas the level of LHCGR expression was extremely low in malignant tumors of adult patients. No difference in the expression level of these receptors was observed in the different forms of adrenocortical hyperplasia.


Subject(s)
Humans , Male , Female , Adrenocortical Hyperfunction , Multiple Endocrine Neoplasia , Gastric Inhibitory Polypeptide , Gene Expression , Immunohistochemistry , Loss of Heterozygosity , Mutation/genetics , Polymerase Chain Reaction , Receptors, LH , Receptors, Peptide
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