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1.
Am J Med Genet A ; 161A(10): 2582-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23929658

RESUMO

West syndrome is a well-recognized form of epilepsy, defined by a triad of infantile spasms, hypsarrhythmia and developmental arrest. West syndrome is heterogenous, caused by mutations of genes ARX, STXBP1, KCNT1 among others; 16p13.11 and 17q21.31 microdeletions are less frequent, usually associated with intellectual disability and facial dysmorphism. So-called "idiopathic" West syndrome is of better prognostic, without prior intellectual deficiency and usually responsive to anti-epileptic treatment. We report on a boy falling within the scope of idiopathic West syndrome, with no dysmorphic features and normal development before the beginning of West syndrome, with a good resolution after treatment, bearing a de novo 15q13.3 microdeletion. Six genes are located in the deleted region, including CHRNA7, which encodes a subunit of a nicotinic acetylcholine receptor, and is frequently associated with epilepsy. Exploration of the 15q13.3 region should be proposed in idiopathic West syndrome.


Assuntos
Transtornos Cromossômicos/complicações , Deficiência Intelectual/complicações , Convulsões/complicações , Espasmos Infantis/complicações , Adulto , Deleção Cromossômica , Transtornos Cromossômicos/diagnóstico , Cromossomos Humanos Par 15 , Hibridização Genômica Comparativa , Eletroencefalografia , Fácies , Feminino , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/diagnóstico , Masculino , Convulsões/diagnóstico , Espasmos Infantis/diagnóstico , Receptor Nicotínico de Acetilcolina alfa7/genética
2.
Prenat Diagn ; 32(4): 383-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22025315

RESUMO

OBJECTIVE: To compare results of array comparative genomic hybridization (CGH) on cell-free fetal (cff) DNA from amniotic fluid supernatant and DNA from cultured amniocytes in high-risk pregnancies. METHOD: We selected 48 cases of high-risk pregnancies (in utero growth retardation [IUGR] and/or at least two fetal malformations [polymalformation]). Bacterial artificial chromosome array CGH (BlueGnome) was performed on 38 fetal samples (frozen cff DNA and DNA from cultured cells) with previously normal karyotypes. RESULTS: From the 38 specimens, we obtained an adequate amount of sufficient quality DNA with a better quality profile using cff DNA compared to cellular DNA. Aberrations of clinical relevance were detected in three fetuses, and copy number variations considered as benign polymorphism were detected in one case using both sources of DNA. This results in an 8% detection rate of significant abnormalities in high-risk pregnancies with a normal karyotype using array CGH (two cases with IUGR, one with polymalformation). CONCLUSION: These findings indicate the possibility of using cff DNA from amniotic fluid supernatant for array CGH with excellent results, even in late pregnancy when culture is no longer available. In this small series, pathogenic copy number variations are detected more often in the presence of IUGR than with polymalformation.


Assuntos
Anormalidades Múltiplas/genética , Amniocentese/métodos , Hibridização Genômica Comparativa/métodos , Variações do Número de Cópias de DNA , Retardo do Crescimento Fetal/genética , Anormalidades Múltiplas/diagnóstico , Adulto , Líquido Amniótico/química , Líquido Amniótico/citologia , Células Cultivadas , Cromossomos Artificiais Bacterianos/genética , DNA/sangue , Feminino , Sangue Fetal/química , Retardo do Crescimento Fetal/diagnóstico , Idade Gestacional , Humanos , Cariótipo , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , Estudos Retrospectivos
3.
J Pediatr Endocrinol Metab ; 35(7): 924-930, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35667691

RESUMO

OBJECTIVES: Gynecomastia may be due to aromatase excess in several diseases such as obesity and cancer. Aromatase excess syndrome (AEXS) is an autosomal dominant disorder caused by overexpression of CYP19A1. Germinal mutations occurring in AEXS include various genomic rearrangements including duplication, deletion, and inversion identified in the upstream region of CYP19A1. Aromatase overexpression caused by a CYP19A1 somatic mutation has been rarely described. METHODS: Breast adipose tissue biopsies or surgical specimens were obtained from 19 subjects with gynecomastia. Aromatase quantification was performed by digital PCR and CYP19A1 sequencing by RACE PCR products. RESULTS: We observed localized aromatase overexpression (>10 fold greater than normal) in breast adipose tissue from three prepubertal males with gynecomastia out of the 19 cases. One carried a chromosomal rearrangement between CYP19A1 and DMXL2, consistent with AEXS. In the 2 others, the first exon of CYP19A1 contained 11 different tissue-specific promoter subtypes, specifically I.4 or I.3 normally expressed by adipose tissue, but also the placental I.2 promoter and the more ubiquitous I.7 which is usually expressed in breast cancer, uterine, and endothelial tissues. No differences in clinical or biochemical characteristics were observed between these 3 subjects and 16 others without aromatase overexpression. CONCLUSIONS: We describe two cases of aromatase overexpression in breast adipose tissue associated with nonspecific promoter recruitment. Further investigations are necessary to understand the mechanisms involved in aberrant promoter selection.


Assuntos
Aromatase , Ginecomastia , Aromatase/genética , Aromatase/metabolismo , Feminino , Ginecomastia/genética , Ginecomastia/patologia , Humanos , Masculino , Erros Inatos do Metabolismo , Gravidez , Regiões Promotoras Genéticas/genética
4.
Endocr J ; 58(9): 769-76, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21720050

RESUMO

This paper reports the case of an infant presenting with sexual ambiguity at birth. The child presented with labia majora synechia, thready genital tubercle and perineal hypospadias. The karyotype was 46,XY. Low testosterone levels with no response to hCG administration, associated with high LH level for her age, high FSH level, high inhibin B levels and normal AMH indicated a lack of LH receptivity and prompted us to screen the LHCGR gene for mutations. A previously described missense mutation (p.Cys131Arg) was identified at homozygous state in the propositus and at heterozygous state in the mother. This variation, however, was not found in the father. Our attention was drawn by the presence of several single nucleotide polymorphisms (SNPs), identified at homozygous state without any paternal contribution from exon 1 to exon 10 of LHCGR, suggesting a paternal deletion. Array DNA analysis was performed revealing a large deletion extending from 61,493 to 135,344 bp and including the LHCGR gene. Adequate genetic counselling was provided. This paper describes the first application of prenatal diagnosis in LHCGR deficiency for 46,XY disorders of sex development with the subsequent delivery of a normal baby.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual/genética , Receptores do LH/genética , Deleção de Sequência , Sequência de Bases , Pré-Escolar , Hibridização Genômica Comparativa , DNA/química , DNA/genética , Transtorno 46,XY do Desenvolvimento Sexual/sangue , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Diagnóstico Pré-Natal/métodos , Análise de Sequência de DNA , Testosterona/sangue
5.
Front Endocrinol (Lausanne) ; 12: 736240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721296

RESUMO

Mutations in CYP24A1 (vitamin D 24-hydroxylase) and SLC34A1 (renal phosphate transporter NPT2a) cause autosomal recessive Infantile Hypercalcemia type 1 and 2, illustrating links between vitamin D and phosphate metabolism. Patients may present with hypercalciuria and alternate between chronic phases with normal serum calcium but inappropriately high 1,25-(OH)2D and appropriately low PTH, and acute phases with hypercalcemia with suppressed PTH. Mutations in SLC34A3 and SLC9A3R1 have been associated with phosphate wasting without hypercalcemia. The aims of this study were to evaluate the frequency of mutations in these genes in patients with a medical history suggestive of CYP24A1 mutation to search for a specific pattern. Using next generation sequencing, we screened for mutations in 185 patients with PTH levels < 20 pg/mL, hypercalcemia and/or hypercalciuria, and relatives. Twenty-eight (15%) patients harbored biallelic mutations in CYP24A1 (25) and SLC34A3 (3), mostly associated with renal disease (lithiasis, nephrocalcinosis) (86%). Hypophosphatemia was found in 7 patients with biallelic mutations in CYP24A1 and a normal phosphatemia was reported in 2 patients with biallelic mutations in SLC34A3. Rare variations in SLC34A1 and SLC34A3 were mostly of uncertain significance. Fifteen patients (8%) carried only one heterozygous mutation. Heterozygous relatives carrying SLC34A1 or SLC34A3 variation may present with biochemical changes in mineral metabolism. Two patients' genotype may suggest digenism (heterozygous variations in different genes). No variation was found in SLC9A3R1. As no specific pattern can be found, patients with medical history suggestive of CYP24A1 mutation should benefit from SLC34A1 and SLC34A3 analysis.


Assuntos
Hipercalcemia/genética , Mutação , Fenótipo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIa/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIc/genética , Vitamina D3 24-Hidroxilase/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Reprod Biomed Online ; 21(1): 56-65, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20457540

RESUMO

Gonadotrophin-releasing hormone (GnRH) agonists and antagonists have been widely used to prevent premature LH surge during ovarian stimulation. However, studies have shown a significantly lower serum oestradiol concentration on the day of human chorionic gonadotrophin administration for cycles using GnRH antagonist. This study compared aromatase gene expression in granulosa lutein cells from 50 women randomly assigned to receive either GnRH agonist (group 1, n=28) or GnRH antagonist (group 2, n=22). The cellular mechanism involved in the observed effects was also investigated. GnRH antagonist treatment significantly affected serum oestradiol concentration (1894+/-138 versus 1074+/-63 pg/ml; P < or = 0.001), follicular-fluid oestradiol concentration in large follicles (18,565+/-2467 versus 10,184+/-1993 pg/ml; P < or = 0.05), aromatase activity (9600+/-1179 versus 5376+/-997 fmol/10(6) cells/h; P < or = 0.05) and mRNA aromatase/mRNA glyceraldehyde 3-phosphate dehydrogenase (15+/-3 versus 6+/-1; P < 0.05). Protein kinase C (PKC) activity in granulosa lutein cells from the GnRH antagonist group was 2.5-fold higher than in the GnRH agonist group. In-vitro experiments showed that selective down-regulation of PKC was only observed in GnRH-desensitized granulosa lutein cells. This report suggests that, in granulosa lutein cells, the modulation of the FSH-induced protein kinase A pathway by PKC was different in agonist versus antagonist cycles.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Indução da Ovulação/métodos , Pamoato de Triptorrelina/uso terapêutico , Adulto , Aromatase/biossíntese , Aromatase/genética , Regulação para Baixo , Estradiol/sangue , Feminino , Líquido Folicular/metabolismo , Hormônio Liberador de Gonadotropina/uso terapêutico , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Humanos , Folículo Ovariano/metabolismo , Gravidez , Taxa de Gravidez , Proteína Quinase C/metabolismo
7.
J Bone Miner Res ; 35(5): 913-919, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31886927

RESUMO

Pseudohypoparathyroidism type 1A (PHP1A) and pseudopseudohypoparathyroidism (PPHP) are two rare autosomal dominant disorders caused by loss-of-function mutations in the imprinted Guanine Nucleotide Binding Protein, Alpha Stimulating Activity (GNAS) gene, coding Gs α. PHP1A is caused by mutations in the maternal allele and results in Albright's hereditary osteodystrophy (AHO) and hormonal resistance, mainly to the parathormone (PTH), whereas PPHP, with AHO features and no hormonal resistance, is linked to mutations in the paternal allele. This study sought to investigate parental transmission of GNAS mutations. We conducted a retrospective study in a population of 204 families with 361 patients harboring GNAS mutations. To prevent ascertainment bias toward a higher proportion of affected children due to the way in which data were collected, we excluded from transmission analysis all probands in the ascertained sibships. After bias correction, the distribution ratio of the mutated alleles was calculated from the observed genotypes of the offspring of nuclear families and was compared to the expected ratio of 50% according to Mendelian inheritance (one-sample Z-test). Sex ratio, phenotype of the transmitting parent, and transmission depending on the severity of the mutation were also analyzed. Transmission analysis was performed in 114 nuclear families and included 250 descendants. The fertility rates were similar between male and female patients. We showed an excess of transmission from mother to offspring of mutated alleles (59%, p = .022), which was greater when the mutations were severe (61.7%, p = .023). Similarly, an excess of transmission was found when the mother had a PHP1A phenotype (64.7%, p = .036). By contrast, a Mendelian distribution was observed when the mutations were paternally inherited. Higher numbers of females within the carriers, but not in noncarriers, were also observed. The mother-specific transmission ratio distortion (TRD) and the sex-ratio imbalance associated to PHP1A point to a role of Gs α in oocyte biology or embryogenesis, with implications for genetic counseling. © 2019 American Society for Bone and Mineral Research.


Assuntos
Cromograninas , Subunidades alfa Gs de Proteínas de Ligação ao GTP , Herança Materna , Pseudo-Hipoparatireoidismo , Criança , Cromograninas/genética , Feminino , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Humanos , Masculino , Mutação , Pseudo-Hipoparatireoidismo/genética , Estudos Retrospectivos
8.
Eur J Med Genet ; 62(7): 103648, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30998997

RESUMO

CANAC1C encodes for the main cardiac L-type calcium channel and mutations on it lead to a prolonged QT interval in Timothy Syndrome (TS). We provide a new de novo constitutional heterozygote missense variation in CACNA1C in a living adult woman, also carrier of the known c.2146-1G>C heterozygous variation of PKP2 inherited from her father. To our knowledge, this patient is the first to have the two variations in these genes. Theses clinical and molecular findings expand the clinical and molecular spectrum of TS and show the interest of next generation sequencing or whole exome sequencing in rare disorders, atypical or novel phenotype.


Assuntos
Transtorno Autístico/genética , Canais de Cálcio Tipo L/genética , Síndrome do QT Longo/genética , Fenótipo , Sindactilia/genética , Adulto , Transtorno Autístico/patologia , Feminino , Heterozigoto , Humanos , Síndrome do QT Longo/patologia , Mutação , Placofilinas/genética , Sindactilia/patologia
9.
Eur J Med Genet ; 62(11): 103577, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30423445

RESUMO

Loss-of-function mutations in CYP24A1 (MIM 126065 20q13.2), the gene encoding the 24-hydroxylase responsible for 25-OH-D and 1,25-(OH)2D degradation, are identified in about 20% of patients presenting Idiopathic Infantile Hypercalcemia (IIH) (MIM 143880). Common features of this autosomal recessive condition included hypercalcemia with hypercalciuria, suppressed PTH and a high 25-OH-D3:24,25-(OH)2D3 ratio. Medical care mainly relies on sun protection and life-long contraindication of vitamin D to avoid complications such as early nephrocalcinosis and renal failure. Molecular diagnosis therefore keeps a crucial place in the diagnosis of IIH, and genetic counseling should be systematically recommended to prevent vitamin D administration in affected siblings. In this report is described the molecular characterization of a CYP24A1 deletion identified in two unrelated families. This highlights the potential role of CYP24A1 copy number variations (CNV) in IIH. Considering the presence of CNV affecting CYP24A1 in public databases, CNV analysis should be systematically added to the sequencing studies in IIH. Targeted Massively Parallel Sequencing (MPS) study coupled with a CNV detection tool called CovCop is a powerful method to detect genic rearrangement and improve genetic analysis.


Assuntos
Hipercalcemia/diagnóstico , Hipercalcemia/genética , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/genética , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/genética , Patologia Molecular , Vitamina D3 24-Hidroxilase/genética , Adolescente , Criança , Pré-Escolar , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Hipercalcemia/tratamento farmacológico , Hipercalcemia/patologia , Lactente , Doenças do Recém-Nascido/tratamento farmacológico , Doenças do Recém-Nascido/patologia , Mutação com Perda de Função/genética , Masculino , Erros Inatos do Metabolismo/tratamento farmacológico , Erros Inatos do Metabolismo/patologia , Nefrocalcinose/tratamento farmacológico , Nefrocalcinose/genética , Nefrocalcinose/prevenção & controle , Insuficiência Renal/tratamento farmacológico , Insuficiência Renal/genética , Insuficiência Renal/prevenção & controle , Deleção de Sequência/genética , Vitamina D/uso terapêutico
10.
Bone ; 123: 145-152, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30905746

RESUMO

Pseudohypoparathyroidism 1B (PHP1B) is caused by maternal epigenetic defects in the imprinted GNAS cluster. PHP1B can follow an autosomal dominant mode of inheritance or occur sporadically (spor-PHP1B). These latter patients present broad methylation changes of two or more differentially methylated regions (DMR) that, when mimicking the paternal allele, raises the suspicious of the occurrence of paternal uniparental disomy of chromosome 20 (upd(20)pat). A cohort of 33 spor-PHP1B patients was screened for upd(20)pat using comparative genomic hybridization with SNP-chip. Methylation analyses were assessed by methylation specific-multiplex ligation-dependent probe amplification. Upd(20)pat was identified in 6 patients, all exhibiting typical paternal methylation pattern compared to normal controls, namely a complete loss of methylation of GNAS A/B:TSS-DMR, negligible methylation at GNAS-AS1:TSS-DMR and GNAS-XL:Ex1-DMR and complete gain of methylation at GNAS-NESP:TSS-DMR. The overall frequency of upd(20) is 18% in our cohort when searched considering both severe and partial loss of imprinting. However, twenty five patients displayed severe methylation pattern and the upd(20)pat frequency reaches 24% when searching in this group. Consequently, up to day, upd(20)pat is the most common anomaly than other genetic alterations in spor-PHP1B patients. Upd(20)pat occurrence is not linked to the parental age in contrast to upd(20)mat, strongly associated with an advanced maternal childbearing age. This study provides criteria to guide further investigations for upd(20)pat needed for an adequate genetic counseling.


Assuntos
Cromossomos Humanos Par 20/genética , Frequência do Gene/genética , Pseudo-Hipoparatireoidismo/diagnóstico , Pseudo-Hipoparatireoidismo/genética , Dissomia Uniparental/genética , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino
11.
Clin Endocrinol (Oxf) ; 68(5): 692-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17980016

RESUMO

OBJECTIVE: Abnormal responsiveness to arginine vasopressin (AVP) was previously observed in cortisol-producing adrenocortical tumours but the mechanism remains unclear. The aim of this study was to characterize the effect of AVP on cortisol secretion from adrenocortical tumours compared to normal human adrenal gland. DESIGN: A multicentre study based on pharmacological, molecular and immunohistochemical experiments performed in adenomatous and normal adrenal tissues. PATIENTS: Twenty patients with adrenocortical adenomas and subclinical Cushing's syndrome (SCCS) or Cushing's syndrome (CS) were compared to six control normal subjects. MEASUREMENTS: In vivo and in vitro cortisol response to vasopressin, vasopressin receptor subtype mRNA measurement by real-time polymerase chain reaction (RT-PCR), immunohistochemical localization of AVP and its V1a receptor in tumour and normal adrenal tissues. RESULTS: Terlipressin in vivo enhanced cortisol plasma levels in 17/20 SCCS and 3/6 CS but in none of the control subjects. In vitro cortisol response to AVP was observed in nine tumours studied, with enhanced efficacy and/or potency of AVP in three SCCS tumours compared to normal tissues. AVP receptor subtype mRNA levels were similar in SCCS, CS cells and normal adrenal cells. Some SCCS tumour steroidogenic cells showed AVP and V1a receptor immunoreactivity. CONCLUSIONS: SCCS and CS adrenocortical tumours often exhibit in vivo and in vitro hyper-responsiveness to AVP, which is not related to vasopressin receptor overexpression, but may be explained by more efficient coupling pathways or by the indirect action of AVP through an autocrine/paracrine mechanism.


Assuntos
Adenoma/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Síndrome de Cushing/tratamento farmacológico , Receptores de Vasopressinas/biossíntese , Vasoconstritores/farmacologia , Adenoma/fisiopatologia , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Adulto , Estudos de Casos e Controles , Síndrome de Cushing/sangue , Feminino , Humanos , Hidrocortisona/sangue , Lipressina/análogos & derivados , Lipressina/farmacologia , Masculino , Pessoa de Meia-Idade , Receptores de Vasopressinas/efeitos dos fármacos , Índice de Gravidade de Doença , Terlipressina
12.
Am J Med Genet A ; 146A(21): 2770-6, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18925665

RESUMO

To assess the practical usefulness of array-comparative genomic hybridization (a-CGH) when supernumerary marker chromosomes (SMCs) are detected during prenatal diagnosis, we retrospectively studied SMC management in our laboratory before a-CGH availability. In this 11-year study, SMCs were observed in 20/16,810 routine karyotypes (0.12%). Their chromosomal origin, ascertained in 13 cases, remained elusive in seven using conventional cytogenetics and FISH. In the literature, most of SMCs (2/3) are easily identified through conventional cytogenetics and targeted FISH, and in these cases a-CGH would have been unneeded. This technique would have been less helpful in nine cases, that is, bisatellited SMC, isochromosomes and translocation derivatives. On the other hand, a-CGH would have been helpful for the 11 remaining cases. It would have improved diagnostic accuracy of six SMC whom chromosomal origin was ascertained by cytogenetics and FISH and for which prognosis was only based on literature and ultrasonographic data. Among five unidentified SMCs, a-CGH would have been more reassuring for four heterochromatic SMCs than normal ultrasonography alone and would have characterized the unidentified case associated with malformations that was interrupted. However potential pitfalls should be outlined. Using high level resolution chip expose to polymorphism detection and misinterpretation, a very sensitive problem in prenatal diagnosis. Moreover, low grade mosaicism could remain undetectable with this technique, leading to erroneous conclusions. Wisest use of a-CGH should be a complementary approach in prenatal management of SMC. It is specifically appropriate when SMC interpretation remains equivocal and only indirectly based on mode of inheritance, literature data and ultrasonography.


Assuntos
Aberrações Cromossômicas , Diagnóstico Pré-Natal/métodos , Adulto , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Hibridização Genômica Comparativa , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/genética , Citogenética , Feminino , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Masculino , Mosaicismo , Gravidez
13.
J Bone Miner Res ; 32(9): 1893-1899, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28548312

RESUMO

Vitamin D requires a two-step activation by hydroxylation: The first step is catalyzed by hepatic 25-hydroxylase (CYP2R1, 11p15.2) and the second one is catalyzed by renal 1α-hydroxylase (CYP27B1, 12q13.1), which produces the active hormonal form of 1,25-(OH)2 D. Mutations of CYP2R1 have been associated with vitamin D-dependent rickets type 1B (VDDR1B), a very rare condition that has only been reported to affect 4 families to date. We describe 7 patients from 2 unrelated families who presented with homozygous loss-of-function mutations of CYP2R1. Heterozygous mutations were present in their normal parents. We identified a new c.124_138delinsCGG (p.Gly42_Leu46delinsArg) variation and the previously published c.296T>C (p.Leu99Pro) mutation. Functional in vitro studies confirmed loss-of-function enzymatic activity in both cases. We discuss the difficulties in establishing the correct diagnosis and the specific biochemical pattern, namely, very low 25-OH-D suggestive of classical vitamin D deficiency, in the face of normal/high concentrations of 1,25-(OH)2 D. Siblings exhibited the three stages of rickets based on biochemical and radiographic findings. Interestingly, adult patients were able to maintain normal mineral metabolism without vitamin D supplementation. One index case presented with a partial improvement with 1alfa-hydroxyvitamin D3 or alfacalcidol (1α-OH-D3 ) treatment, and we observed a dramatic increase in the 1,25-(OH)2 D serum concentration, which indicated the role of accessory 25-hydroxylase enzymes. Lastly, in patients who received calcifediol (25-OH-D3 ), we documented normal 24-hydroxylase activity (CYP24A1). For the first time, and according to the concept of personalized medicine, we demonstrate dramatic improvements in patients who were given 25-OH-D therapy (clinical symptoms, biochemical data, and bone densitometry). In conclusion, the current study further expands the CYP2R1 mutation spectrum. We note that VDDR1B could be easily mistaken for classical vitamin D deficiency. © 2017 American Society for Bone and Mineral Research.


Assuntos
Colestanotriol 26-Mono-Oxigenase/deficiência , Família 2 do Citocromo P450/deficiência , Erros de Diagnóstico , Ergocalciferóis/administração & dosagem , Mutação , Raquitismo , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/deficiência , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Raquitismo/diagnóstico , Raquitismo/tratamento farmacológico , Raquitismo/enzimologia , Raquitismo/genética , Vitamina D/análogos & derivados , Vitamina D/sangue
14.
J Steroid Biochem Mol Biol ; 101(2-3): 127-35, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16901689

RESUMO

Aromatase protein is synthesized in response to gonadotropins that activate expression of their target genes via the cAMP second messenger system. The -882/+103 bp region of the rabbit ovarian promoter (PII) was ligated to a luciferase vector and transfected into granulosa cells to elucidated the mechanism by which cAMP stimulates transcription. Deletions and mutational experiments indicate that (i) a cAMP-response element-like sequence (CLS) present at -208 to -200 bp is the main element required for the activation of the rabbit PII by cAMP and that (ii) both nuclear receptor element sites; NREA (-133/-126 bp) and NREB (-188/-181 bp) do not participate to the cAMP-dependent activity of the PII. The replacement of the specific rabbit NREA site by the human NREA site increases two-fold the cAMP response and indicates that trans-activating factors are present in rabbit granulosa cells. This study shows for the first time an efficient aromatase transcription occurs in granulosa cells in absence of a consensus NREA site. In addition a comparative study has been performed on the sheep aromatase promoter where sites deviate from rabbit. Mutagenesis experiments suggest that some of them are involved in the cAMP-induced response of the rabbit PII.


Assuntos
Aromatase/genética , Células da Granulosa/enzimologia , Regiões Promotoras Genéticas , Ovinos/genética , Transcrição Gênica , Animais , Sequência de Bases , Células Cultivadas , AMP Cíclico/genética , Feminino , Proteínas de Homeodomínio/genética , Dados de Sequência Molecular , Coelhos , Receptores Citoplasmáticos e Nucleares/genética , Homologia de Sequência do Ácido Nucleico , Fator Esteroidogênico 1 , Fatores de Transcrição/genética , Ativação Transcricional , Transfecção
15.
Eur J Cancer ; 41(18): 2924-34, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16289616

RESUMO

To elucidate the molecular profile of oestrogen receptors alpha and beta (ERalpha, ERbeta) we studied ERalpha and ERbeta expression at the mRNA and protein levels using real-time polymerase chain reaction (RT-PCR), Western blot analysis and immunohistochemical (IHC) methods in 41 primary breast cancers and surrounding tissues. ERalpha mRNA and ERbeta mRNA were detected in all of the breast cancer and normal matched tissues analysed. ERalpha mRNA levels showed greater diversity than ERbeta mRNA levels and the range of amount of ERbeta transcripts was far smaller than that of ERalpha. At the protein level, the percentage of ERalpha- or ERbeta-positive cases changed. Seventy percent of the tumours studied produced full-length 65 kDa ERalpha protein in Western blot analysis and 67% of assessed cases were positive in IHC. Full-length 57 kDa ERbeta protein was detected by Western blotting in 97% of analysed breast cancers, while 67% were ERbeta-positive using IHC. ERalpha was localised in the nucleus, while cytoplasmic and perinuclear localisation of ERbeta was observed in normal as well as in breast cancer cells. The amount of ERalpha (but not ERbeta) increased with age. The expression of ERalpha correlated positively with progesterone receptor and negatively with proliferation marker Ki-67. These results confirm the previous observations that the lack of ERalpha protein expression is not due to lack of ERalpha gene expression or methylation of ERalpha promoter, but due to post-transcriptional or post-translational mechanisms. Our investigation also suggests that ERalpha is more dysregulated in breast cancer, and thereby ERbeta is more tightly regulated in the tumour.


Assuntos
Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Antígeno Ki-67/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Neoplasias da Mama/patologia , Proliferação de Células , DNA Complementar/metabolismo , Eletroforese em Gel de Ágar , Feminino , Humanos , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Hum Mutat ; 22(4): 340, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12955726

RESUMO

In recent years, some patients bearing "atypical" forms of cystic fibrosis (CF) with normal sweat chloride concentrations have been described. To identify the spectrum of mutant combinations causing such atypical CF, we collected the results of CFTR (ABCC7) mutation analysis from 15 laboratories. Thirty patients with one or more typical symptoms of the disease associated with normal or borderline sweat chloride levels and bearing two CFTR mutations were selected. Phenotypes and genotypes of these 30 patients are described. A total of 18 different CFTR mutations were observed in the 60 chromosomes analysed. F508del was present in 31.6 % of the mutated chromosomes and 3849+10kbC>T in 13.3 %. R117H, D1152H, L206W, 3272-26A>G, S1235R, G149R, R1070W, S945L, and the poly-T tract variation commonly called IVS8-5T were also observed. The relative frequency of CFTR mutations clearly differed from that observed in typical CF patients or in CBAVD patients with the same ethnic origin. A mild genotype with one or two mild or variable mutations was observed in all the patients. These findings improve our understanding of the distribution of CFTR alleles in CF with normal or borderline sweat chloride concentrations and will facilitate the development of more sensitive CFTR mutation screening.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Mutação , Adolescente , Adulto , Criança , Pré-Escolar , Cloretos/análise , Fibrose Cística/diagnóstico , Análise Mutacional de DNA , Genótipo , Humanos , Lactente , Pessoa de Meia-Idade , Fenótipo , Suor/química
17.
Endocrinology ; 144(11): 4790-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12960046

RESUMO

In rabbit granulosa cells, two cytochrome P450 aromatase (P450 arom) mRNAs issued from promoter II were described: a full-length and a truncated transcript. Western blot analysis showed two P450 arom proteins with apparent molecular masses of 53 and 46 kDa, which are consistent with the predicted theoretical sizes of proteins encoded by these two transcripts. To examine the involvement of the truncated transcript in the regulation of P450 arom gene expression, the level of each transcript was specifically quantified in cultured granulosa cells by competitive quantitative RT-PCR. FSH induced a dose-dependent increase in both estradiol production and P450 arom mRNAs levels with a much more enhancement in the full-length mRNA. The half-life of the transcripts could not explain this differential regulation. Upon dibutyryl cAMP stimulation, the full-length mRNA was less abundant than the truncated one. In contrast, Western blot analysis revealed a stimulation of the 53-kDa protein content, whereas the 46-kDa protein amount was apparently unaffected. TGF beta in FSH-stimulated conditions decreased both estradiol production and P450 arom transcripts levels. TGF beta did not modify estradiol production and aromatase protein amounts induced by dibutyryl cAMP, whereas the two P450 arom mRNAs levels were increased. In conclusion, we report for the first time that a protein encoded by a truncated P450 arom mRNA could be involved in the regulation of estrogen production. Moreover, we show that the two P450 arom mRNAs are regulated in a differential manner, probably through hormonal control of the alternative splicing.


Assuntos
Aromatase/genética , Fase Folicular/metabolismo , Regulação da Expressão Gênica , Variação Genética , Células da Granulosa/enzimologia , RNA Mensageiro/metabolismo , Animais , Aromatase/metabolismo , Sequência de Bases/genética , Bucladesina/farmacologia , Células Cultivadas , Estradiol/biossíntese , Feminino , Hormônio Foliculoestimulante/farmacologia , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Estabilidade de RNA , Coelhos , Fator de Crescimento Transformador beta/farmacologia
18.
Eur J Endocrinol ; 148(4): 457-61, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12656667

RESUMO

A 30-year-old male was referred for the rapid development of gynecomastia, and dramatic hyperestrogenemia was assessed: plasma estrone, estradiol but also cortisol were not suppressed by high-dose dexamethasone, while gonadotropin pulsatility was completely abolished. A 60-mm right adrenal tumor was evidenced on computed tomography-scan, and the patient underwent adrenalectomy. The tumor was found to express a moderate increase in aromatase activity compared with adjacent non-neoplastic adrenal tissue. Quantitative RT-PCR also showed a weak and non-significant increase in total aromatase mRNA in the tumor compared with normal adrenal tissue. Aromatase transcripts were mainly promoter PII-derived, but different patterns of aromatase minor transcripts were found: promoter I.3- and I.6-derived transcripts were identified in the tumor, while only promoter I.4-derived transcripts were found in normal adrenal. This case report demonstrates that a sharp aromatase overexpression is not a prerequisite for clinical and biochemical hyperestrogenism, and further characterizes the aromatase promoter utilization in this feminizing adrenocortical tumor and in the normal adrenal cortex.


Assuntos
Adenoma/complicações , Neoplasias do Córtex Suprarrenal/complicações , Aromatase/genética , Estrogênios/sangue , Feminização/etiologia , Expressão Gênica , 17-alfa-Hidroxiprogesterona/análise , Adenoma/enzimologia , Adenoma/cirurgia , Córtex Suprarrenal/química , Neoplasias do Córtex Suprarrenal/enzimologia , Neoplasias do Córtex Suprarrenal/cirurgia , Adrenalectomia , Adulto , Androstenodiona/análise , Aromatase/metabolismo , Estradiol/análise , Estrona/análise , Ginecomastia/etiologia , Humanos , Masculino , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testosterona/análise
19.
Fertil Steril ; 79(2): 442-4, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12568864

RESUMO

OBJECTIVE: To screen for mutations in the GnRH receptor gene in a case of complete hypogonadotropic hypogonadism (HH) with GnRH resistance. DESIGN: Case report. SETTING: A university hospital. PATIENT(S): A male patient with the complete form of HH without anosmia. INTERVENTION(S): Physical examination and laboratory and genetic studies. MAIN OUTCOME MEASURE(S): Gonadotropins at the basal state and after GnRH administration and GnRH receptor DNA sequencing. RESULT(S): A novel missense mutation, localized in the first amino acid of the extracellular loop found in the heterozygous state, and another mutation, Arg(139)His (R139H), located in the conserved aspartate-arginine-serine motif at the junction of the third transmembrane and second intracellular loop of the GnRH receptor, were identified in the homozygous state. Pedigree studies reveal that both parents were heterozygous for R139H, while the mother carried the missense mutation at codon 1(M1T). CONCLUSION(S): GnRH receptor mutations may account for a larger proportion of cases of HH than previously thought. The phenotypic spectrum of HH seems to vary, and this heterogeneity may be related, at least in part, to the degree of impaired biological activity of the mutated GnRH receptor caused by the allelic type of mutations.


Assuntos
Hipogonadismo/genética , Mutação de Sentido Incorreto , Receptores LHRH/genética , Adulto , Estrogênios/sangue , Humanos , Hidrocortisona/sangue , Masculino , Testosterona/sangue
20.
Eur J Endocrinol ; 168(3): 437-44, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23243014

RESUMO

BACKGROUND: The bone morphogenetic proteins (BMPs) are growth factors involved in the folliculogenesis. Alteration in their expression may compromise the reproductive process in disease such as the polycystic ovary syndrome (PCOS). This study investigated the expression and role of granulosa cell (GC) BMP from normal cycling and PCOS women. METHODS AND RESULTS: This prospective study was performed in GCs obtained from 14 patients undergoing IVF: i) six women with normal ovulatory cycles and tubal or male infertility and ii) eight women with PCOS. BMP2, BMP4, BMP5, BMP6, BMP7, and BMP8A and their receptors BMPR1A, BMPR1B, and BMPR2 were identified by RT-PCR in GCs from normally cycling and PCOS women. BMP4, BMP6, and BMP7 expressions were confirmed by immunohistochemistry. Quantitative transcript analysis showed the predominant expression of BMP6. In GCs from PCOS women, an overexpression of BMP6 (P<0.01) and BMPR1A mRNA (P<0.05) was observed. GC culture experiments demonstrated that basal estradiol (E2) production was threefold higher but FSH-induced E2 increment was twofold lower in PCOS compared with controls. In PCOS, BMP6 and BMP7 exerted a stimulatory effect on basal E2 production while BMP4 and BMP6 inhibited FSH-induced E2 production. FSH receptor and aromatase expression were not different between both groups. CONCLUSION: The BMP system is expressed in human GCs from normal cycling and PCOS women. The BMP may be involved in reproductive abnormalities found in PCOS.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Regulação da Expressão Gênica , Células da Granulosa/metabolismo , Síndrome do Ovário Policístico/metabolismo , Esteroides/metabolismo , Adulto , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Proteína Morfogenética Óssea 6/genética , Proteína Morfogenética Óssea 6/metabolismo , Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/genética , Células Cultivadas , Estradiol/metabolismo , Feminino , Hormônio Foliculoestimulante Humano/metabolismo , Células da Granulosa/patologia , Humanos , Imuno-Histoquímica , Síndrome do Ovário Policístico/patologia , Estudos Prospectivos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Adulto Jovem
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