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1.
Nature ; 617(7961): 616-622, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36972684

RESUMO

Steroid hormone receptors are ligand-binding transcription factors essential for mammalian physiology. The androgen receptor (AR) binds androgens mediating gene expression for sexual, somatic and behavioural functions, and is involved in various conditions including androgen insensitivity syndrome and prostate cancer1. Here we identified functional mutations in the formin and actin nucleator DAAM2 in patients with androgen insensitivity syndrome. DAAM2 was enriched in the nucleus, where its localization correlated with that of the AR to form actin-dependent transcriptional droplets in response to dihydrotestosterone. DAAM2 AR droplets ranged from 0.02 to 0.06 µm3 in size and associated with active RNA polymerase II. DAAM2 polymerized actin directly at the AR to promote droplet coalescence in a highly dynamic manner, and nuclear actin polymerization is required for prostate-specific antigen expression in cancer cells. Our data uncover signal-regulated nuclear actin assembly at a steroid hormone receptor necessary for transcription.


Assuntos
Actinas , Forminas , Proteínas Nucleares , Receptores Androgênicos , Transcrição Gênica , Humanos , Actinas/metabolismo , Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/metabolismo , Androgênios/farmacologia , Androgênios/metabolismo , Forminas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Polimerização/efeitos dos fármacos , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , RNA Polimerase II/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esteroides/metabolismo , Esteroides/farmacologia , Testosterona/análogos & derivados , Transcrição Gênica/efeitos dos fármacos
2.
Eur J Endocrinol ; 188(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36721956

RESUMO

OBJECTIVE: Congenital defects of androgen synthesis or action in 46,XY individuals can result in impaired virilisation, despite the apparent testicular development. In a recent case, report of a young adult with complete androgen insensitivity syndrome (CAIS), tumourous gonadal tissue was shown to express HSD17B3 in Sertoli cells (SCs) and not in Leydig cells (LCs). This expression pattern differs from the typical adult human testis and resembles a foetal mouse testis, suggesting an underlying testicular development and function defect. Here, we investigate the effect of altered androgen signalling in gonads from five 46,XY individuals with defects in androgen synthesis or action. METHODS: Gonadal tissue sections from four patients with CAIS, one with CYP17A1 deficiency, and one control were immunostained for LC developmental and steroidogenic markers. The expression of some of these markers during development was investigated by reanalysing previously published single-cell RNA sequencing (scRNA-seq) data from normal human testicular tissues. RESULTS: All gonadal tissues from the patients show an exclusive expression of HSD17B3 in SCs and an expression of the foetal/immature LC marker DLK1 in a subset of LCs, suggesting an androgen-dependent differentiation defect of adult SCs and LCs. Furthermore, reanalysis of scRNA-seq data reveals an expression of HSD17B3 in foetal and neonatal SCs that is downregulated in adult SCs. CONCLUSIONS: Androgen signalling may affect the differentiation of adults, but possibly not foetal SCs or LCs, and may induce a shift of testosterone production from the tubular compartment in the foetal phase to the interstitial compartment in the adult phase.


Assuntos
Síndrome de Resistência a Andrógenos , Androgênios , Animais , Humanos , Masculino , Camundongos , Adulto Jovem , Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/metabolismo , Androgênios/metabolismo , Gônadas , Células Intersticiais do Testículo/metabolismo , Testículo/metabolismo , Testosterona/metabolismo
3.
Endocrine ; 76(3): 722-732, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35258786

RESUMO

PURPOSE: To study differences in metabolic outcomes between testosterone and estradiol replacement in probands with complete androgen insensitivity syndrome (CAIS). METHODS: In this multicentre, double-blind, randomized crossover trial, 26 women with CAIS were included of whom 17 completed the study. After a two-months run in phase with estradiol, probands either received transdermal estradiol followed by crossover to transdermal testosterone or vice versa. After six months, differences in lipids, fasting glucose, insulin, hematocrit, liver parameters and blood pressure between the treatment phases were investigated. RESULTS: Linear mixed models adjusted for period and sequence did not reveal major group differences according to treatment for the investigated outcomes. In each treatment group, there were however significant uniform changes in BMI and cholesterol. BMI increased significantly, following six months of estradiol ( + 2.7%; p = 0.036) as well as testosterone treatment ( + 2.8%; p = 0.036). There was also a significant increase in total ( + 10.4%; p = 0.001) and LDL-cholesterol ( + 29.2%; p = 0.049) and a decrease in HDL-cholesterol (-15.8%; p < 0.001) following six months of estradiol as well as six months of testosterone treatment (total cholesterol: + 14.6%; p = 0.008; LDL-cholesterol: + 39.1%; p = 0.005, HDL-cholesterol: -15.8%; p = 0.004). Other parameters remained unchanged. CONCLUSION: Transdermal estradiol as well as testosterone treatment in women with CAIS results in worsening in lipid profiles. Given the relatively small sample size, subtle group differences in other metabolic parameters may have remained undetected.


Assuntos
Síndrome de Resistência a Andrógenos , Testosterona , Síndrome de Resistência a Andrógenos/tratamento farmacológico , Colesterol , HDL-Colesterol , Estradiol/uso terapêutico , Feminino , Humanos , Masculino , Testosterona/uso terapêutico
4.
Sex Dev ; 16(1): 34-45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34689141

RESUMO

This study describes the clinical, biochemical, and molecular characteristics of Indian children with 46,XY DSD and suspected androgen insensitivity syndrome (AIS). Fifty children (median age 3.0 years, range 0-16.5 years) with 46,XY DSD and a suspected diagnosis of AIS were enrolled. Sanger sequencing was performed to identify pathogenic variants in the androgen receptor (AR) gene and to study genotype-phenotype correlations. All 5 (100%) patients with CAIS and 14/45 (31%) patients with PAIS had pathogenic/likely pathogenic variants in the AR gene (overall, 14 different variants in 19 patients; 38.8%). There was no significant difference in clinical (cryptorchidism, hypospadias, or external masculinizing score) or biochemical parameters (gonadotropins and testosterone) between patients with or without pathogenic variants. However, patients with AIS were more likely to have a positive family history, be assigned female gender at birth, and present with gynaecomastia at puberty. Three novel pathogenic/likely pathogenic variants, including one splice donor site variant c.2318+1G>A, one frameshift variant p.H790Lfs*40, and one missense variant p.G821E, were identified in 3 patients with CAIS. The missense variant p.G821E was predicted as deleterious, damaging, disease-causing, and likely functionally inactive by in silico analysis and protein modelling study. Two previously not reported pathogenic/likely pathogenic variants, including p.R386H and p.G396R, were identified in patients with PAIS. This study contributes in expanding the spectrum of pathogenic variants in the AR gene in patients with AIS. Only 31% patients with a provisional diagnosis of PAIS had pathogenic variants in the AR gene, suggesting other possible mechanisms or candidate genes may be responsible for such a phenotypic presentation.


Assuntos
Síndrome de Resistência a Andrógenos , Receptores Androgênicos , Adolescente , Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/patologia , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Masculino , Mutação , Receptores Androgênicos/genética , Testosterona
5.
J Clin Endocrinol Metab ; 103(12): 4617-4627, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30124873

RESUMO

Context: Inactivating mutations within the AR gene are present in only ~40% of individuals with clinically and hormonally diagnosed androgen insensitivity syndrome (AIS). Previous studies revealed the existence of an AR gene mutation-negative group of patients with AIS who have compromised androgen receptor (AR) function (AIS type II). Objective: To investigate whether AIS type II can be due to epigenetic repression of AR transcription. Design: Quantification of AR mRNA and AR proximal promoter CpG methylation levels in genital skin-derived fibroblasts (GFs) derived from patients with AIS type II and control individuals. Setting: University hospital endocrine research laboratory. Patients: GFs from control individuals (n = 11) and patients with AIS type II (n = 14). Main Outcome Measure(s): Measurement of AR mRNA and AR promoter CpG methylation as well as activity of AR proximal promoter in vitro. Results: Fifty-seven percent of individuals with AIS type II (n = 8) showed a reduced AR mRNA expression in their GFs. A significant inverse correlation was shown between AR mRNA abundance and methylation at two consecutive CpGs within the proximal AR promoter. Methylation of a 158-bp-long region containing these CpGs was sufficient to severely reduce reporter gene expression. This region was bound by the runt related transcription factor 1 (RUNX1). Ectopic expression of RUNX1 in HEK293T cells was able to inhibit reporter gene expression through this region. Conclusions: Aberrant CpGs methylation within the proximal AR promoter plays an important role in the control of AR gene expression and may result in AIS type II. We suggest that transcriptional modifiers, such as RUNX1, could play roles therein offering new perspectives for understanding androgen-mediated endocrine diseases.


Assuntos
Síndrome de Resistência a Andrógenos/genética , Metilação de DNA , Repressão Epigenética , Receptores Androgênicos/genética , Adolescente , Biópsia , Células Cultivadas , Criança , Pré-Escolar , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Ilhas de CpG/genética , Fibroblastos/metabolismo , Genitália Masculina , Células HEK293 , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Receptores Androgênicos/metabolismo , Pele/citologia , Pele/metabolismo , Pele/patologia
6.
Lancet Diabetes Endocrinol ; 6(10): 771-780, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30075954

RESUMO

BACKGROUND: Women with complete androgen insensitivity syndrome (CAIS) after gonadectomy have complained about reduced psychological wellbeing and sexual satisfaction. The aim of this study was to compare the effectiveness of hormone-replacement therapy with either androgen or oestrogen in women with 46,XY karyotype and CAIS after gonadectomy. METHODS: This national, multicentre, double-blind, randomised crossover trial was performed at three university medical centres and three specialised treatment institutions in Germany. Eligible participants were women aged 18-54 years with 46,XY karyotype, genetically diagnosed CAIS, and removed gonads. Participants were randomly assigned (14:12) by a central computer-based minimisation method to either oestradiol 1·5 mg/day for 6 months followed by crossover to testosterone 50 mg/day for 6 months (sequence A) or to testosterone 50 mg/day for 6 months followed by crossover to oestradiol 1·5 mg/day for 6 months (sequence B). Participants also received oestradiol or testosterone dummy to avoid identification of the active substance. All participants received oestradiol 1·5 mg/day during a 2 months' run-in phase. The primary outcome was mental health-related quality of life, as measured with the standardised German version of the SF-36 questionnaire. Secondary outcomes were psychological wellbeing, as measured with the Brief Symptom Inventory (BSI), sexual function, as measured with the Female Sexual Function Index (FSFI), and somatic effects, such as signs of virilisation and effects on metabolic blood values. The primary analysis included all patients who were available at least until visit 5, even if protocol violations occurred. The safety analysis included all patients who received at least oestradiol during the run-in phase. This trial is registered with the German Clinical Trials Register, number DRKS00003136, and with the European Clinical Trials Database, number 2010-021790-37. FINDINGS: We enrolled 26 patients into the study, with the first patient enrolled on Nov 7, 2011, and the last patient leaving the study on Jan 23, 2016. 14 patients were assigned to sequence A and 12 were assigned to sequence B. Ten participants were withdrawn from the study, two of whom attended at least five visits and so could be included in the primary analysis. Mental health-related quality of life did not differ between treatment groups (linear mixed model, p=0·794), nor did BSI scores for psychological wellbeing (global severity index, p=0·638; positive symptom distress index, p=0·378; positive symptom total, p=0·570). For the FSFI, testosterone was superior to oestradiol only in improving sexual desire (linear mixed model, p=0·018). No virilisation was observed, and gonadotrophin concentrations remained stable in both treatment groups. Oestradiol and testosterone concentrations changed substantially during the study in both treatment groups. 28 adverse events were reported for patients receiving oestradiol (23 grade 1 and five grade 2), and 38 adverse events were reported for patients receiving testosterone (34 grade 1, three grade 2, and one grade 3). One serious adverse event (fibrous mastopathy) and 20 adverse events (16 grade 1 and four grade 2) were reported during the run-in phase, and 12 adverse events during follow-up (nine grade 1 and three grade 2). INTERPRETATION: Testosterone was well tolerated and as safe as oestrogen for hormone-replacement therapy. Testosterone can be an alternative hormone substitution in CAIS, especially for woment with reduced sexual functioning. FUNDING: German Federal Ministry of Education and Research.


Assuntos
Síndrome de Resistência a Andrógenos/tratamento farmacológico , Androgênios/uso terapêutico , Castração/efeitos adversos , Estradiol/uso terapêutico , Terapia de Reposição Hormonal , Testosterona/uso terapêutico , Adulto , Síndrome de Resistência a Andrógenos/etiologia , Síndrome de Resistência a Andrógenos/psicologia , Método Duplo-Cego , Terapia de Reposição de Estrogênios , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Orgasmo/efeitos dos fármacos , Resultado do Tratamento , Adulto Jovem
7.
Horm Res Paediatr ; 87(5): 354-358, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27951541

RESUMO

BACKGROUND: 17ß-hydroxysteroid dehydrogenase (17ß-HSD) type 3 deficiency is an autosomal recessive disorder with diminished testosterone synthesis and consequently underandrogenisation. 46,XY patients with 17ß-HSD type 3 deficiency are often assigned a female sex at birth but have a high virilisation potential at the time of puberty. METHODS: We studied four 46,XY patients with 17ß-HSD type 3 deficiency at puberty with regard to the underlying mutations, the hormone values, and the clinical findings. RESULTS: Three patients were initially assigned a female sex and 1 was assigned a male sex. All had relevant mutations in the HSD17B3 gene. The 2 patients with deleterious mutations had lower testosterone values at the time of puberty than the patients with possible residual activity of 17ß-HSD type 3. One of the latter patients changed to male gender. CONCLUSION: All 4 patients with 17ß-HSD type 3 deficiency synthesized relevant amounts (>0.7 µg/L) of testosterone at puberty, which lead to variable androgenisation. In patients with presumable residual activity of the mutated enzyme, testosterone values in the male reference range can be achieved, thereby inducing male pubertal development. These patients should possibly be assigned a male sex. Any surgical intervention should be avoided until the patients are old enough to consider their options of medical and surgical intervention.
.


Assuntos
17-Hidroxiesteroide Desidrogenases/deficiência , Transtorno 46,XY do Desenvolvimento Sexual , Ginecomastia , Mutação , Puberdade , Erros Inatos do Metabolismo de Esteroides , Virilismo , 17-Hidroxiesteroide Desidrogenases/genética , Adolescente , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtorno 46,XY do Desenvolvimento Sexual/patologia , Transtorno 46,XY do Desenvolvimento Sexual/fisiopatologia , Feminino , Ginecomastia/genética , Ginecomastia/patologia , Ginecomastia/fisiopatologia , Humanos , Masculino , Erros Inatos do Metabolismo de Esteroides/genética , Erros Inatos do Metabolismo de Esteroides/patologia , Erros Inatos do Metabolismo de Esteroides/fisiopatologia , Virilismo/genética , Virilismo/patologia , Virilismo/fisiopatologia
8.
Eur J Endocrinol ; 175(6): P1-P17, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27401862

RESUMO

OBJECTIVE: Disorders caused by impairments in the parathyroid hormone (PTH) signalling pathway are historically classified under the term pseudohypoparathyroidism (PHP), which encompasses rare, related and highly heterogeneous diseases with demonstrated (epi)genetic causes. The actual classification is based on the presence or absence of specific clinical and biochemical signs together with an in vivo response to exogenous PTH and the results of an in vitro assay to measure Gsa protein activity. However, this classification disregards other related diseases such as acrodysostosis (ACRDYS) or progressive osseous heteroplasia (POH), as well as recent findings of clinical and genetic/epigenetic background of the different subtypes. Therefore, the EuroPHP network decided to develop a new classification that encompasses all disorders with impairments in PTH and/or PTHrP cAMP-mediated pathway. DESIGN AND METHODS: Extensive review of the literature was performed. Several meetings were organised to discuss about a new, more effective and accurate way to describe disorders caused by abnormalities of the PTH/PTHrP signalling pathway. RESULTS AND CONCLUSIONS: After determining the major and minor criteria to be considered for the diagnosis of these disorders, we proposed to group them under the term 'inactivating PTH/PTHrP signalling disorder' (iPPSD). This terminology: (i) defines the common mechanism responsible for all diseases; (ii) does not require a confirmed genetic defect; (iii) avoids ambiguous terms like 'pseudo' and (iv) eliminates the clinical or molecular overlap between diseases. We believe that the use of this nomenclature and classification will facilitate the development of rationale and comprehensive international guidelines for the diagnosis and treatment of iPPSDs.


Assuntos
Proteína Relacionada ao Hormônio Paratireóideo , Hormônio Paratireóideo , Pseudo-Hipoparatireoidismo/classificação , Pseudo-Hipoparatireoidismo/diagnóstico , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/classificação , Doenças Ósseas Metabólicas/diagnóstico , Disostoses/sangue , Disostoses/classificação , Disostoses/diagnóstico , Europa (Continente) , Humanos , Deficiência Intelectual/sangue , Deficiência Intelectual/classificação , Deficiência Intelectual/diagnóstico , Ossificação Heterotópica/sangue , Ossificação Heterotópica/classificação , Ossificação Heterotópica/diagnóstico , Osteocondrodisplasias/sangue , Osteocondrodisplasias/classificação , Osteocondrodisplasias/diagnóstico , Hormônio Paratireóideo/sangue , Proteína Relacionada ao Hormônio Paratireóideo/sangue , Pseudo-Hipoparatireoidismo/sangue , Dermatopatias Genéticas/sangue , Dermatopatias Genéticas/classificação , Dermatopatias Genéticas/diagnóstico
9.
PLoS One ; 11(4): e0154158, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110943

RESUMO

A subset of patients with monogenic disorders lacks disease causing mutations in the protein coding region of the corresponding gene. Here we describe a recurrent germline mutation found in two unrelated patients with complete androgen insensitivity syndrome (CAIS) generating an upstream open reading frame (uORF) in the 5' untranslated region (5'-UTR) of the androgen receptor (AR) gene. We show in patient derived primary genital skin fibroblasts as well as in cell-based reporter assays that this mutation severely impacts AR function by reducing AR protein levels without affecting AR mRNA levels. Importantly, the newly generated uORF translates into a polypeptide and the expression level of this polypeptide inversely correlates with protein translation from the primary ORF of the AR thereby providing a model for AR-5'UTR mediated translational repression. Our findings not only add a hitherto unrecognized genetic cause to complete androgen insensitivity but also underline the importance of 5'UTR mutations affecting uORFs for the pathogenesis of monogenic disorders in general.


Assuntos
Regiões 5' não Traduzidas , Síndrome de Resistência a Andrógenos/genética , Fibroblastos/metabolismo , Mutação em Linhagem Germinativa , Biossíntese de Proteínas , Receptores Androgênicos/genética , Síndrome de Resistência a Andrógenos/metabolismo , Síndrome de Resistência a Andrógenos/patologia , Sequência de Bases , Fibroblastos/patologia , Mutação da Fase de Leitura , Regulação da Expressão Gênica , Genes Reporter , Humanos , Luciferases/genética , Luciferases/metabolismo , Masculino , Fases de Leitura Aberta , Cultura Primária de Células , Receptores Androgênicos/metabolismo , Análise de Sequência de DNA
10.
J Clin Endocrinol Metab ; 100(7): E1022-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25927242

RESUMO

BACKGROUND: 46,XY disorders of sex development (DSD) comprise a heterogeneous group of congenital conditions. Mutations in a variety of genes can affect gonadal development or androgen biosynthesis/action and thereby influence the development of the internal and external genital organs. OBJECTIVE: The objective of the study was to identify the genetic cause in two 46,XY sisters of a consanguineous family with DSD and gonadal tumor formation. METHODS: We used a next-generation sequencing approach by exome sequencing. Electrophysiological and high-resolution ultrasound examination of peripheral nerves as well as histopathological examination of the gonads were performed. RESULTS: We identified a novel homozygous R124Q mutation in the desert hedgehog gene (DHH), which alters a conserved residue among the three mammalian Hedgehog ligands sonic hedgehog, Indian hedgehog, and desert hedgehog. No other relevant mutations in DSD-related genes were encountered. The gonads of one patient showed partial gonadal dysgenesis with loss of Leydig cells in tubular areas with seminoma in situ and a hyperplasia of Leydig cell-like cells expressing CYP17A1 in more dysgenetic parts of the gonad. In addition, both patients suffer from a polyneuropathy. High-resolution ultrasound revealed a structural change of peripheral nerve structure that fits well to a minifascicle formation of peripheral nerves. CONCLUSION: Mutations in DHH play a role in 46,XY gonadal dysgenesis and are associated with seminoma formation and a neuropathy with minifascicle formation. Gonadal dysgenesis in these cases may be due to impairment of Sertoli cell-Leydig cell interaction during gonadal development.


Assuntos
Disgenesia Gonadal 46 XY/genética , Proteínas Hedgehog/genética , Homozigoto , Mutação , Adolescente , Adulto , Sequência de Bases , Análise Mutacional de DNA/métodos , Exoma , Feminino , Disgenesia Gonadal 46 XY/diagnóstico por imagem , Disgenesia Gonadal 46 XY/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Seminoma/genética , Seminoma/patologia , Irmãos , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Ultrassonografia
11.
Sex Dev ; 9(2): 69-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25613104

RESUMO

Little is known about gonadotropins and sex steroid levels in postpubertal women with complete androgen insensitivity syndrome (CAIS). In order to define reproductive hormone profiles in women with CAIS and intact gonads, 42 postpubertal females with proven CAIS (age range 14-50 years) with testes in situ were examined. Reproductive hormone values [testosterone (T), estradiol (E2), sex hormone-binding globulin (SHBG), luteinizing hormone (LH), follicle-stimulating hormone (FSH)] were assessed by commercially available immunoassays. In women with CAIS, LH levels (median 18.5 IU/l, range 5.5-51.1 IU/l) were elevated above the usual adult reference ranges, whereas FSH values (3.5 IU/l, 0.4-16.3 IU/l) were not. Basal T (20 nmol/l, 6-52 nmol/l) and E2 values (113 pmol/l; 18-257 pmol/l) were found in the usual adult male reference ranges; SHBG levels (53 nmol/l, 15-180 nmol/l) were in the adult female reference range. Calculated free androgen indices (Tx10³/SHBG: 380, 114-863) and aromatization indices (E2/T: 0.052, 0.020-0.196) did not differ from the reference ranges for adult men given in the literature (Tx10³/SHBG: 315-936; E2/T: 0.03-0.07). Reproductive hormone profiles in women with CAIS do not follow the usual male/female pattern, suggesting a specific postpubertal hormone milieu. Albeit calculation of CAIS-specific reference ranges requires larger series and standardization of laboratory methods, these results may be a prerequisite for the identification of pathologic hormone patterns in women with CAIS and gonads in situ. The present data will also be useful to monitor hormone replacement therapy in individuals with removed gonads.


Assuntos
Síndrome de Resistência a Andrógenos/metabolismo , Hormônios/metabolismo , Reprodução , Adolescente , Adulto , Feminino , Hormônio Foliculoestimulante/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Masculino , Mutação/genética , Receptores Androgênicos/genética
12.
Sex Dev ; 8(6): 350-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25401426

RESUMO

The androgen insensitivity syndrome (AIS) is described as a dysfunction of the androgen receptor (AR) in 46,XY individuals, which can be associated with mutations in the AR gene or can be due to unknown mechanisms. Different mutations in AIS generally cause variable phenotypes that range from a complete hormone resistance to a mild form usually associated with male infertility. The purpose of this study was to search for mutations in the AR gene in a fertile man with gynecomastia and to evaluate the influence of the mutation on the AR transactivation ability. Sequencing of the AR gene revealed the p.Pro695Ser mutation. It is located within the AR ligand-binding domain. Bioinformatics analysis indicated a deleterious role, which was verified after testing transactivation activity and N-/C-terminal (N/C) interaction by in vitro expression of a reporter gene and 2-hybrid assays. p.Pro695Ser showed low levels of both transactivation activity and N/C interaction at low dihydrotestosterone (DHT) conditions. As the ligand concentration increased, both transactivation activity and N/C interaction also increased and reached normal levels. Therefore, this study provides functional insights for the p.Pro695Ser mutation described here for the first time in a patient with mild AIS. The expression profile of p.Pro695Ser not only correlates to the patient's phenotype, but also suggests that a high-dose DHT therapy may overcome the functional deficit of the mutant AR.


Assuntos
Fertilidade/genética , Predisposição Genética para Doença , Ginecomastia/genética , Mutação/genética , Receptores Androgênicos/genética , Adulto , Western Blotting , Criança , Humanos , Masculino , Proteínas Mutantes/metabolismo , Ativação Transcricional/genética
13.
Semin Reprod Med ; 30(5): 432-42, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23044881

RESUMO

The androgen insensitivity syndromes (AIS) fall within the generic category of 46,XY DSD (disorder of sex development) and present as phenotypes associated with complete or partial resistance to the action of androgens. Three categories are recognized: complete androgen insensitivity syndrome (CAIS), partial androgen insensitivity syndrome (PAIS), mild androgen insensitivity syndrome (MAIS). The androgen receptor (AR) is encoded by an 8 exon gene on the X chromosome long arm. More than 800 mutations in the AR gene have been reported in AIS patients (www.androgendb.mcgill.ca/). They are distributed throughout the gene with a preponderance located in the ligand binding domain. The most severe mutations are generally associated with a CAIS phenotype, but the correlation is less defined in PAIS. CAIS presents typically as primary amenorrhoea in an adolescent female and less commonly in infancy with bilateral inguinal/labial swellings due to testes. The differential diagnosis in CAIS is limited, whereas in PAIS, numerous other causes of DSD can also produce the typical phenotype of micropenis, severe hypospadias and bifid scrotum. Management issues in CAIS involve timing of gonadectomy, appropriate hormone replacement therapy and assessment of the need for vaginal dilation or rarely, vaginal surgery. The risk of gonadal germ cell tumor is low during childhood and adolescence but increases in later adulthood. Expert psychological counseling is mandatory to manage the disconnect between chromosomal, gonadal and phenotypic sex and to choreograph the evolving process of disclosure from late childhood through to maturity. It is implicit that management in AIS requires a multidisciplinary team and engagement with patient advocacy groups.


Assuntos
Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/terapia , Mutação , Receptores Androgênicos/genética , Síndrome de Resistência a Andrógenos/embriologia , Síndrome de Resistência a Andrógenos/fisiopatologia , Androgênios/metabolismo , Animais , Desenvolvimento Fetal , Humanos , Masculino , Defesa do Paciente , Equipe de Assistência ao Paciente , Estrutura Terciária de Proteína , Qualidade de Vida , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Índice de Gravidade de Doença , Testículo/embriologia , Testículo/metabolismo
14.
Mol Cell Endocrinol ; 358(1): 53-62, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-22406838

RESUMO

During embryogenesis, the development of the male genital is dependent on androgens. Their actions are mediated by the androgen receptor (AR), which functions as a transcription factor. To identify AR coregulators that support AR action during the critical time window of androgen-dependent development in the genital tubercle of male mice, we performed yeast two-hybrid screenings with cDNA libraries of genital tubercles from male mouse embryos using human AR as bait. RWD domain containing 1 (RWDD1) was identified as an AR-interacting protein from three independent libraries of the embryonic days E15, E16 and E17. The interaction between the AR and RWDD1 was confirmed in vitro and in vivo and the ligand binding domain of the AR was shown to be sufficient to mediate the interaction. RWDD1 enhanced AR-dependent transactivation in reporter assays with promoters of different complexity and in different cell lines. These results suggest that RWDD1 functions as a coactivator of androgen-dependent transcription.


Assuntos
Genitália Masculina/embriologia , Proteínas/metabolismo , Receptores Androgênicos/metabolismo , Ativação Transcricional , Animais , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Regulação da Expressão Gênica no Desenvolvimento , Genitália Masculina/metabolismo , Células HeLa , Humanos , Masculino , Camundongos , Proteínas/genética , Receptores Androgênicos/genética
15.
Hum Mutat ; 32(6): 653-60, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21488135

RESUMO

Pseudohypoparathyroidism type Ia (PHPIa) is caused by GNAS mutations leading to deficiency of the α-subunit of stimulatory G proteins (Gsα) that mediate signal transduction of G protein-coupled receptors via cAMP. PHP type Ic (PHPIc) and PHPIa share clinical features of Albright hereditary osteodystrophy (AHO); however, in vitro activity of solubilized Gsα protein is normal in PHPIc but reduced in PHPIa. We screened 32 patients classified as PHPIc for GNAS mutations and identified three mutations (p.E392K, p.E392X, p.L388R) in four unrelated families. These and one novel mutation associated with PHPIa (p.L388P) were introduced into a pcDNA3.1(-) expression vector encoding Gsα wild-type and expressed in a Gsα-null cell line (Gnas(E2-/E2-) ). To investigate receptor-mediated cAMP accumulation, we stimulated the endogenous expressed ß(2) -adrenergic receptor, or the coexpressed PTH or TSH receptors, and measured the synthesized cAMP by RIA. The results were compared to receptor-independent cholera toxin-induced cAMP accumulation. Each of the mutants associated with PHPIc significantly reduced or completely disrupted receptor-mediated activation, but displayed normal receptor-independent activation. In contrast, PHPIa associated p.L388P disrupted both receptor-mediated activation and receptor-independent activation. We present a new subgroup of PHP that is caused by Gsα deficiency and selectively affects receptor coupling functions of Gsα.


Assuntos
Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Pseudo-Hipoparatireoidismo/genética , Adolescente , Sequência de Aminoácidos , Linhagem Celular , Criança , Pré-Escolar , Cromograninas , AMP Cíclico/metabolismo , Feminino , Displasia Fibrosa Poliostótica/genética , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Mutação , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/genética
16.
J Clin Endocrinol Metab ; 92(5): 1764-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17299070

RESUMO

OBJECTIVE: The GNAS gene encodes the alpha-subunit of stimulatory G proteins, which play a crucial role in intracellular signal transduction of peptide and neurotransmitter receptors. In addition to transcript variants that differ in their first exon due to different promoters, there are two long (Gsalpha-L) and two short (Gsalpha-S) splice variants, created by alternative splicing. Heterozygous inactivating maternally inherited mutations of GNAS lead to a phenotype in which Albright hereditary osteodystrophy is associated with pseudohypoparathyroidism type Ia. METHODS AND RESULTS: The GNAS gene of a 10-yr-old girl with brachymetacarpia, mental retardation, normocalcemic pseudohypoparathyroidism, and hypothyroidism was investigated. We found a heterozygous insertion of an adenosine in exon 3 altering codon 85 and leading to a frame shift inducing a stop codon in exon 4. Molecular studies of cDNA from blood RNA demonstrated normal, biallelic expression of Gsalpha-S transcripts, whereas expression of Gsalpha-L transcripts from the maternal allele was reduced. Immunoblot analysis revealed a reduced Gsalpha-L protein level to about 50%, whereas the protein level of Gsalpha-S was unaltered. Furthermore, the Gsalpha protein activity in erythrocyte membranes was diminished to about 75% of normal. Both the reduced activity and the mutation were also found in the mother and the affected younger brother. CONCLUSION: This report demonstrates the first evidence for a pathogenic mutation in exon 3 of the GNAS gene. The mutation is associated with a phenotype of Albright hereditary osteodystrophy and pseudohypoparathyroidism type Ia due to selective deficiency of Gsalpha-L and a partial reduction of Gsalpha activity.


Assuntos
Displasia Fibrosa Poliostótica/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Pseudo-Hipoparatireoidismo/genética , Alelos , Cálcio/sangue , Pré-Escolar , Cromograninas , Membrana Eritrocítica/química , Éxons/genética , Feminino , Humanos , Hipotireoidismo/genética , Immunoblotting , Deficiência Intelectual/genética , Hormônio Paratireóideo/sangue , Mutação Puntual/genética , Polimorfismo Conformacional de Fita Simples , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Mol Med (Berl) ; 84(11): 919-31, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16932916

RESUMO

Normal genital skin fibroblasts (GSF) and the human prostate carcinoma cell line LNCaP have been used widely as cell culture models of genital origin to study androgen receptor (AR) signaling. We demonstrate that LNCaP shows a reproducible response to androgens as assessed using cDNA-microarrays representing approximately 32,000 unique human genes, whereas several independent GSF strains are virtually unresponsive. We show that LNCaP cells express markedly higher AR protein levels likely contributing to the observed differences of androgen responsiveness. However, previous data suggested that AR-expression levels alone do not determine androgen responsiveness of human GSF compared to LNCaP. We hypothesized that cell-specific differences in expression levels of AR coregulators might contribute to differences in androgen responsiveness and might be found by comparing LNCaP and GSFs. Using the Canadian McGill-database of AR coregulators ( http://www.mcgill.ca/androgendb ), we identified 61 AR-coregulator genes represented by 282 transcripts on our microarray platform that was used to measure transcript profiles of LNCaP and GSF cells. Baseline expression levels of 48 AR-coregulator transcripts representing 33 distinct genes showed significant differences between GSF and LNCaP, four of which we confirmed by reverse transcriptase polymerase chain reaction. Compared to LNCaP, GSFs displayed significant upregulation of AR coregulators that can function as repressors of AR-transactivation, such as caveolin 1. Analysis of a recently published comprehensive dataset of 115 microarrays representing 35 different human tissues revealed tissue-specific signatures of AR coregulators that segregated with ontogenetically related groups of tissues (e.g., lymphatic system and genital tissues, brain). Our data demonstrate the existence of cell-line and tissue-specific expression patterns of molecules with documented AR coregulatory functions. Therefore, differential expression patterns of AR coregulators could modify tissue-specificity and diversity of androgen actions in development, physiology, and disease.


Assuntos
Androgênios/metabolismo , Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Receptores Androgênicos/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica , Androgênios/farmacologia , Western Blotting , Linhagem Celular Tumoral , Análise por Conglomerados , Bases de Dados Genéticas , Fibroblastos/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias da Próstata/metabolismo , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos
18.
J Clin Endocrinol Metab ; 90(1): 538-41, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15507506

RESUMO

Disruption of the P450 side-chain cleavage cytochrome (P450scc) enzyme due to deleterious mutations of the CYP11A1 gene is thought to be incompatible with fetal survival because of impaired progesterone production by the fetoplacental unit. We present a 46,XY patient with a homozygous disruption of CYP11A1. The child was born prematurely with complete sex reversal and severe adrenal insufficiency. Laboratory data showed diminished or absent steroidogenesis in all pathways. Molecular genetic analysis of the CYP11A1 gene revealed a homozygous single nucleotide deletion leading to a premature termination at codon position 288. This mutation will delete highly conserved regions of the P450scc enzyme and thus is predicted to lead to a nonfunctional protein. Both healthy parents were heterozygous for this mutation. Our report demonstrates that severe disruption of P450scc can be compatible with survival in rare instances. Furthermore, defects in this enzyme are inherited in an autosomal-recessive fashion, and heterozygote carriers can be healthy and fertile. The possibility of P450scc-independent pathways of steroid synthesis in addition to the current concept of luteoplacental shift of progesterone synthesis in humans has to be questioned.


Assuntos
Insuficiência Adrenal/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Transtornos do Desenvolvimento Sexual , Mutação , Trabalho de Parto Prematuro/etiologia , Adulto , Feminino , Deleção de Genes , Humanos , Recém-Nascido , Gravidez , Progesterona/biossíntese
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