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1.
Clin Endocrinol (Oxf) ; 93(3): 248-260, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32347971

RESUMO

OBJECTIVE: Familial hypocalciuric hypercalcaemia type 1 (FHH1), related to heterozygous loss-of-function mutations of the calcium-sensing receptor gene, is the main differential diagnosis for primary hyperparathyroidism. The aim of our study was to describe clinical characteristics of adult patients living in France with a genetically confirmed FHH1. DESIGN AND PATIENTS: This observational, retrospective, multicentre study included 77 adults, followed up in 32 clinical departments in France, with a genetic FHH1 diagnosis between 2001 and 2012. RESULTS: Hypercalcaemia was diagnosed at a median age of 53 years [IQR: 38-61]. The diagnosis was made after clinical manifestations, routine analysis or familial screening in 56, 34 and 10% of cases, respectively, (n = 58; data not available for 19 patients). Chondrocalcinosis was present in 11/51 patients (22%), bone fractures in 8/56 (14%) and renal colic in 6/55 (11%). The median serum calcium was 2.74 mmol/L [IQR: 2.63-2.86 mmol/L], the median plasma parathyroid hormone level was 4.9 pmol/L [3.1-7.1], and the median 24-hour urinary calcium excretion was 2.8 mmol/24 hours [IQR: 1.9-4.0]. Osteoporosis (dual X-ray absorptiometry) or kidney stones (renal ultrasonography) were found in 6/38 patients (16%) and 9/32 patients (28%), respectively. Fourteen patients (18%) underwent parathyroid surgery; parathyroid adenoma was found in three patients (21%) and parathyroid hyperplasia in nine patients (64%). No correlation between genotype and phenotype was established. CONCLUSION: This large cohort study demonstrates that FHH1 clinical characteristics can be atypical in 33 patients (43%). Clinicians should be aware of this rare differential diagnosis in order to adopt an appropriate treatment strategy.


Assuntos
Hipercalcemia , Hiperparatireoidismo Primário , Adulto , Cálcio , Estudos de Coortes , Humanos , Hipercalcemia/congênito , Hipercalcemia/diagnóstico , Hipercalcemia/genética , Hiperparatireoidismo Primário/diagnóstico , Hiperparatireoidismo Primário/genética , Pessoa de Meia-Idade , Receptores de Detecção de Cálcio/genética , Estudos Retrospectivos
2.
Hum Mol Genet ; 26(20): 3883-3894, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29016851

RESUMO

Type 2 acrodysostosis (ACRDYS2), a rare developmental skeletal dysplasia characterized by short stature, severe brachydactyly and facial dysostosis, is caused by mutations in the phosphodiesterase (PDE) 4D (PDE4D) gene. Several arguments suggest that the mutations should result in inappropriately increased PDE4D activity, however, no direct evidence supporting this hypothesis has been presented, and the functional consequences of the mutations remain unclear. We evaluated the impact of four different PDE4D mutations causing ACRDYS2 located in different functional domains on the activity of PDE4D3 expressed in Chinese hamster ovary cells. Three independent approaches were used: the direct measurement of PDE activity in cell lysates, the evaluation of intracellular cAMP levels using an EPAC-based (exchange factor directly activated by cAMP) bioluminescence resonance energy transfer sensor , and the assessment of PDE4D3 activation based on electrophoretic mobility. Our findings indicate that PDE4D3s carrying the ACRDYS2 mutations are more easily activated by protein kinase A-induced phosphorylation than WT PDE4D3. This occurs over a wide range of intracellular cAMP concentrations, including basal conditions, and result in increased hydrolytic activity. Our results provide new information concerning the mechanism whereby the mutations identified in the ACRDYS2 dysregulate PDE4D activity, and give insights into rare diseases involving the cAMP signaling pathway. These findings may offer new perspectives into the selection of specific PDE inhibitors and possible therapeutic intervention for these patients.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Disostoses/genética , Deficiência Intelectual/genética , Osteocondrodisplasias/genética , Adulto , Animais , Células CHO , Cricetulus , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Disostoses/enzimologia , Disostoses/metabolismo , Ativação Enzimática , Feminino , Humanos , Deficiência Intelectual/enzimologia , Deficiência Intelectual/metabolismo , Mutação , Osteocondrodisplasias/enzimologia , Osteocondrodisplasias/metabolismo , Fosforilação , Transdução de Sinais
3.
Ann Surg Oncol ; 26(8): 2640-2650, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31025231

RESUMO

BACKGROUND: The management of intraductal papillary mucinous neoplasms (IPMNs) is mainly based on imaging features and clinical symptoms, and remains challenging. OBJECTIVE: The aim of this study was to assess GNAS, RAS family (KRAS, NRAS and HRAS), BRAF, and PIK3CA mutation status in resected IPMNs and correlate it with clinicopathological characteristics and patient survival. METHODS: Overall, 149 consecutive unselected patients who underwent pancreatectomy for IPMNs were included. After dissection from formalin-fixed and paraffin-embedded tumors, GNAS mutational screening was assessed by allelic discrimination using Taqman® probes and confirmed by SNaPshot analysis. RAS family, BRAF, and PIK3CA mutational screening was assessed by high resolution melt and Sanger sequencing. RESULTS: Gastric- and intestinal-type IPMNs were the most frequent lesions (52% and 41%, respectively). Intestinal-type IPMNs were more frequently associated high-grade dysplasia (49%) and were the only IPMNs associated with colloid-type carcinoma. All pancreatobiliary IPMNs were invasive lesions, located in the main pancreatic duct. GNAS-activating mutations were strongly associated with the intestinal phenotype (p < 10-4), while RAS pathway mutations were not associated with any particular phenotype. Mutations within other members of the epidermal growth factor receptor (EGFR) pathway were very rare (2%). GNAS-mutated IPMNs were rarely invasive (11%) and almost exclusively (83%) of the colloid type. For invasive lesions, multivariate analyses determined that only node negativity was associated with improved cancer-specific survival, but, in univariate analysis, GNAS mutation was associated with prolonged survival. CONCLUSION: In patients selected for surgery, GNAS mutation analysis and tumor phenotype can help to better predict patient prognosis. In the near future, a more precise mutational analysis of IPMNs might help to better tailor their management.


Assuntos
Adenocarcinoma Mucinoso/patologia , Carcinoma Ductal Pancreático/patologia , Cromograninas/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Mutação , Pancreatectomia/mortalidade , Neoplasias Pancreáticas/patologia , Proteínas ras/genética , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/cirurgia , Idoso , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Fenótipo , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida
4.
Pediatr Nephrol ; 33(7): 1263-1267, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29594503

RESUMO

BACKGROUND: Hyperphosphatemic familial tumoral calcinosis (HFTC) is a rare autosomal recessive disease caused by mutations in genes encoding FGF23 or its regulators, and leading to functional deficiency or resistance to fibroblast growth factor 23 (FGF23). Subsequent biochemical features include hyperphosphatemia due to increased renal phosphate reabsorption, and increased or inappropriately normal 1,25-dihydroxyvitamin D (1,25-D) levels. CASE-DIAGNOSIS/TREATMENT: A 15-year-old girl was referred for a 1.2-kg-calcified mass of the thigh, with hyperphosphatemia (2.8 mmol/L); vascular impairment and soft tissue calcifications were already present. DNA sequencing identified compound heterozygous mutations in the FGF23 gene. Management with phosphate dietary restriction, phosphate binders (sevelamer, aluminum, nicotinamide), and acetazolamide moderately decreased serum phosphate levels; oral ketoconazole was secondary administered, leading to significantly decreased 1,25-D levels albeit only moderate additionally decreased phosphate levels. However, therapeutic compliance was questionable. Serum phosphate levels always remained far above the upper normal limit for age. The patient presented with two relapses of the thigh mass, requiring further surgery. CONCLUSIONS: We suggest that control of phosphate metabolism is crucial to prevent recurrences and vascular complications in HFTC; however, the medical management remains challenging.


Assuntos
Calcinose/terapia , Quelantes/uso terapêutico , Diuréticos/uso terapêutico , Fatores de Crescimento de Fibroblastos/genética , Hiperostose Cortical Congênita/terapia , Hiperfosfatemia/terapia , Fosfatos/metabolismo , Adolescente , Nádegas/diagnóstico por imagem , Nádegas/cirurgia , Calcinose/sangue , Calcinose/diagnóstico , Calcinose/genética , Terapia Combinada/métodos , Análise Mutacional de DNA , Feminino , Fator de Crescimento de Fibroblastos 23 , Heterozigoto , Humanos , Hiperostose Cortical Congênita/sangue , Hiperostose Cortical Congênita/diagnóstico , Hiperostose Cortical Congênita/genética , Hiperfosfatemia/sangue , Hiperfosfatemia/diagnóstico , Hiperfosfatemia/genética , Imageamento por Ressonância Magnética , Fosfatos/sangue , Resultado do Tratamento
5.
J Biol Chem ; 290(46): 27816-28, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26405036

RESUMO

The main target of cAMP is PKA, the main regulatory subunit of which (PRKAR1A) presents mutations in two genetic disorders: acrodysostosis and Carney complex. In addition to the initial recurrent mutation (R368X) of the PRKAR1A gene, several missense and nonsense mutations have been observed recently in acrodysostosis with hormonal resistance. These mutations are located in one of the two cAMP-binding domains of the protein, and their functional characterization is presented here. Expression of each of the PRKAR1A mutants results in a reduction of forskolin-induced PKA activation (measured by a reporter assay) and an impaired ability of cAMP to dissociate PRKAR1A from the catalytic PKA subunits by BRET assay. Modeling studies and sensitivity to cAMP analogs specific for domain A (8-piperidinoadenosine 3',5'-cyclic monophosphate) or domain B (8-(6-aminohexyl)aminoadenosine-3',5'-cyclic monophosphate) indicate that the mutations impair cAMP binding locally in the domain containing the mutation. Interestingly, two of these mutations affect amino acids for which alternative amino acid substitutions have been reported to cause the Carney complex phenotype. To decipher the molecular mechanism through which homologous substitutions can produce such strikingly different clinical phenotypes, we studied these mutations using the same approaches. Interestingly, the Carney mutants also demonstrated resistance to cAMP, but they expressed additional functional defects, including accelerated PRKAR1A protein degradation. These data demonstrate that a cAMP binding defect is the common molecular mechanism for resistance of PKA activation in acrodysosotosis and that several distinct mechanisms lead to constitutive PKA activation in Carney complex.


Assuntos
Complexo de Carney/enzimologia , Complexo de Carney/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Disostoses/enzimologia , Disostoses/genética , Deficiência Intelectual/enzimologia , Deficiência Intelectual/genética , Osteocondrodisplasias/enzimologia , Osteocondrodisplasias/genética , Substituição de Aminoácidos , Técnicas de Transferência de Energia por Ressonância de Bioluminescência , Códon sem Sentido , Colforsina/farmacologia , AMP Cíclico/metabolismo , AMP Cíclico/farmacologia , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/química , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Humanos , Mutação de Sentido Incorreto , Hormônio Paratireóideo/farmacologia , Estrutura Terciária de Proteína , Tireotropina/farmacologia , Transcrição Gênica
6.
Am J Med Genet A ; 170(3): 734-42, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26640227

RESUMO

Autosomal-dominant brachydactyly type E is a congenital limb malformation characterized by small hands and feet as a result of shortened metacarpals and metatarsals. Alterations that predict haploinsufficiency of PTHLH, the gene coding for parathyroid hormone related protein (PTHrP), have been identified as a cause of this disorder in seven families. Here, we report three patients affected with brachydactyly type E, caused by PTHLH mutations expected to result in haploinsufficiency, and discuss our data compared to published reports.


Assuntos
Braquidactilia/diagnóstico , Braquidactilia/genética , Mutação , Proteína Relacionada ao Hormônio Paratireóideo/genética , Adulto , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Criança , Feminino , Loci Gênicos , Humanos , Linhagem , Fenótipo , Sítios de Splice de RNA , Deleção de Sequência
7.
N Engl J Med ; 364(23): 2218-26, 2011 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-21651393

RESUMO

The skeletal dysplasia characteristic of acrodysostosis resembles the Albright's hereditary osteodystrophy seen in patients with pseudohypoparathyroidism type 1a, but defects in the α-stimulatory subunit of the G-protein (GNAS), the cause of pseudohypoparathyroidism type 1a, are not present in patients with acrodysostosis. We report a germ-line mutation in the gene encoding PRKAR1A, the cyclic AMP (cAMP)-dependent regulatory subunit of protein kinase A, in three unrelated patients with acrodysostosis and resistance to multiple hormones. The mutated subunit impairs the protein kinase A response to stimulation by cAMP; this explains our patients' hormone resistance and the similarities of their skeletal abnormalities with those observed in patients with pseudohypoparathyroidism type 1a.


Assuntos
Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Mutação em Linhagem Germinativa , Hormônios/metabolismo , Adolescente , Criança , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Resistência a Medicamentos , Disostoses/genética , Disostoses/metabolismo , Feminino , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/metabolismo , Masculino , Osteocondrodisplasias/genética , Osteocondrodisplasias/metabolismo , Hormônio Paratireóideo/metabolismo , Linhagem , Transcrição Gênica , Adulto Jovem
8.
Hum Mutat ; 34(8): 1172-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23649963

RESUMO

Most patients with pseudohypoparathyroidism type 1b (PHP-1b) display a loss of imprinting (LOI) encompassing the GNAS locus resulting in PTH resistance. In other imprinting disorders, such as Russell-Silver or Beckwith-Wiedemann syndrome, we and others have shown that the LOI is not restricted to one imprinted locus but may affect other imprinted loci for some patients. Therefore, we hypothesized that patients with PHP-1b might present multilocus imprinting defects. We investigated, in 63 patients with PHP-1b, the methylation pattern of eight imprinted loci: GNAS, ZAC1, PEG1/MEST, ICR1, and ICR2 on chromosome 11p15, SNRPN, DLK1/GTL2 IG-DMR, and L3MBTL1. We found multilocus imprinting defects in four PHP-1b patients carrying broad LOI at the GNAS locus (1) simultaneous hypermethylation at L3MBTL1 differentially methylated region 3 (DMR3), and hypomethylation at PEG1/MEST DMR (n = 1), (2) hypermethylation at the L3MBTL1 (DMR3) (n = 1) and at the DLK1/GTL2 IG-DMR (n = 1), and (3) hypomethylation at the L3MBTL1 DMR3 (n = 1). We suggest that mechanisms underlying multilocus imprinting defects in PHP-1b differ from those of other imprinting disorders having only multilocus loss of methylation. Furthermore, our results favor the hypothesis of "epidominance", that is, the phenotype is controlled by the most severely affected imprinted locus.


Assuntos
Metilação de DNA , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Impressão Genômica , Polimorfismo de Nucleotídeo Único , Pseudo-Hipoparatireoidismo/genética , Cromograninas , Estudos de Coortes , Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Humanos , Pseudo-Hipoparatireoidismo/metabolismo
10.
J Med Genet ; 48(1): 55-63, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20972248

RESUMO

BACKGROUND: Pseudohypoparathyroidism type Ib (PHP-Ib) is due to epigenetic changes at the imprinted GNAS locus, including loss of methylation at the A/B differentially methylated region (DMR) and sometimes at the XL and AS DMRs and gain of methylation at the NESP DMR. OBJECTIVE: To investigate if quantitative measurement of the methylation at the GNAS DMRs identifies subtypes of PHP-Ib. DESIGN AND METHODS: In 19 patients with PHP-Ib and 7 controls, methylation was characterised at the four GNAS DMRs through combined bisulfite restriction analysis and quantified through cytosine specific real-time PCR in blood lymphocyte DNA. RESULTS: A principal component analysis using the per cent of methylation at seven cytosines of the GNAS locus provided three clusters of subjects (controls n=7, autosomal dominant PHP-Ib with loss of methylation restricted to the A/B DMR n=3, and sporadic PHP-Ib with broad GNAS methylation changes n=16) that matched perfectly the combined bisulfite restriction analysis classification. Furthermore, three sub-clusters of patients with sporadic PHP-Ib, that displayed different patterns of methylation, were identified: incomplete changes at all DMRs compatible with somatic mosaicism (n=5), profound epigenetic changes at all DMRs (n=8), and unmodified methylation at XL in contrast with the other DMRs (n=3). Interestingly, parathyroid hormone concentration at the time of diagnosis correlated with the per cent of methylation at the A/B DMR. CONCLUSION: Quantitative assessment of the methylation in blood lymphocyte DNA is of clinical relevance, allows the diagnosis of PHP-Ib, and identifies subtypes of PHP-Ib. These epigenetic findings suggest mosaicism at least in some patients.


Assuntos
Metilação de DNA/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Adolescente , Adulto , Criança , Cromograninas , Epigênese Genética , Feminino , Genes Dominantes , Humanos , Masculino , Fenótipo , Pseudo-Hipoparatireoidismo/classificação , Pseudo-Hipoparatireoidismo/genética , Análise de Sequência de DNA , Pseudo-Hipoparatireoidismo
11.
Endocr Connect ; 11(1)2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-34939939

RESUMO

Context: Recent guidelines have provided recommendations for the care of patients with chronic hypoparathyroidism. Very little is known about actual physicians' practices or their adherence to such guidelines. Objective: To describe the physicians' practice patterns and their compliance with international guidelines. Design: The cohort studies included were Épi-Hypo (118 physicians and 107 patients, from September 2016 to December 2019) and ePatients (110 patients, November 2019). Methods: Internet-based cohorts involving all settings at a nationwide level (France). Participants were (i) physicians treating patients with chronic hypoparathyroidism and patients with chronic hypoparathyroidism either participating in the (ii) Épi-Hypo study (Épi-Hypo 2019 patients), or (iii) Hypoparathyroidism France, the national representative association (ePatients). Results: The physicians' specialties were mainly endocrinology (61%), nephrology (28%), family medicine (2.5%), pediatrics (2.5%), rheumatology (2%), or miscellaneous (4%) and 45% were practicing in public universities. The median number of pharmaceutical drug classes prescribed was three per patient. The combination of active vitamin D and calcium salt was given to 59 and 58% of ePatients and Épi-Hypo 2019 patients, respectively. Eighty-five percent of ePatients and 87% of physicians reported monitoring plasma calcium concentrations at a steady state at least twice a year. In 32 and 26% of cases, respectively, ePatients and physicians reported being fully in accordance with international guidelines that recommend targeting symptoms, plasma calcium and phosphate values, and urine calcium excretion. Conclusions: The care of patients with chronic hypoparathyroidism involves physicians with very different practices, so guidelines should include and target other specialists as well as endocrinologists. Full adherence to the guidelines is low in France.

12.
N Engl J Med ; 359(11): 1128-35, 2008 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-18784102

RESUMO

Impaired renal phosphate reabsorption, as measured by dividing the tubular maximal reabsorption of phosphate by the glomerular filtration rate (TmP/GFR), increases the risks of nephrolithiasis and bone demineralization. Data from animal models suggest that sodium-hydrogen exchanger regulatory factor 1 (NHERF1) controls renal phosphate transport. We sequenced the NHERF1 gene in 158 patients, 94 of whom had either nephrolithiasis or bone demineralization. We identified three distinct mutations in seven patients with a low TmP/GFR value. No patients with normal TmP/GFR values had mutations. The mutants expressed in cultured renal cells increased the generation of cyclic AMP (cAMP) by parathyroid hormone (PTH) and inhibited phosphate transport. These NHERF1 mutations suggest a previously unrecognized cause of renal phosphate loss in humans.


Assuntos
Desmineralização Patológica Óssea/genética , Cálculos Renais/genética , Nefrolitíase/genética , Hormônio Paratireóideo/metabolismo , Fosfatos/metabolismo , Fosfoproteínas/genética , Trocadores de Sódio-Hidrogênio/genética , Adulto , Animais , Transporte Biológico/genética , Desmineralização Patológica Óssea/metabolismo , Desmineralização Patológica Óssea/fisiopatologia , Células Cultivadas , AMP Cíclico/biossíntese , AMP Cíclico/urina , Análise Mutacional de DNA , Feminino , Taxa de Filtração Glomerular/genética , Humanos , Hipercalciúria/genética , Rim/citologia , Rim/metabolismo , Cálculos Renais/metabolismo , Cálculos Renais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mutação , Mutação de Sentido Incorreto , Nefrolitíase/metabolismo , Gambás , Hormônio Paratireóideo/sangue , Fosfatos/sangue
13.
Nephrol Ther ; 17(6): 466-472, 2021 Oct.
Artigo em Francês | MEDLINE | ID: mdl-33994136

RESUMO

We describe here the case report of a young man of 34-years old suffering from a haemorrhagic rectocolitis and presenting with marked hypophosphatemia secondary to an infusion of ferric-carboxymaltose. The renal phosphate wasting was asserted by a very low renal maximal reabsorption rate of phosphate associated with a high plasma FGF-23 level. Three months later we explored the patient and his father since we learnt that both of them had suffered from kidney stones for years with marked hypercalciuria. Kidney stones were composed of weddellite and carbapatite. We suspected a familial phosphate renal wasting syndrome but however no mutation of the renal phosphate carriers could be identified.


Assuntos
Hipofosfatemia , Cálculos Renais , Adulto , Fator de Crescimento de Fibroblastos 23 , Humanos , Hipofosfatemia/diagnóstico , Hipofosfatemia/etiologia , Rim , Mutação , Fosfatos
14.
Hum Mol Genet ; 17(18): 2766-75, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18559376

RESUMO

PTHR1-signaling pathway is critical for the regulation of endochondral ossification. Thus, abnormalities in genes belonging to this pathway could potentially participate in the pathogenesis of Ollier disease/Maffucci syndrome, two developmental disorders defined by the presence of multiple enchondromas. In agreement, a functionally deleterious mutation in PTHR1 (p.R150C) was identified in enchondromas from two of six unrelated patients with enchondromatosis. However, neither the p.R150C mutation (26 tumors) nor any other mutation in the PTHR1 gene (11 patients) could be identified in another study. To further define the role of PTHR1-signaling pathway in Ollier disease and Maffucci syndrome, we analyzed the coding sequences of four genes (PTHR1, IHH, PTHrP and GNAS1) in leucocyte and/or tumor DNA from 61 and 23 patients affected with Ollier disease or Maffucci syndrome, respectively. We identified three previously undescribed missense mutations in PTHR1 in patients with Ollier disease at the heterozygous state. Two mutations (p.G121E, p.A122T) were present only in enchondromas, and one (p.R255H) in both enchondroma and leukocyte DNA. Assessment of receptor function demonstrated that these three mutations impair PTHR1 function by reducing either the affinity of the receptor for PTH or the receptor expression at the cell surface. These mutations were not found in DNA from 222 controls. Including our data, PTHR1 functionally deleterious mutations have now been identified in five out 31 enchondromas from Ollier patients. These findings provide further support for the idea that heterozygous mutations in PTHR1 that impair receptor function participate in the pathogenesis of Ollier disease in some patients.


Assuntos
Encondromatose/genética , Encondromatose/fisiopatologia , Mutação de Sentido Incorreto , Receptor Tipo 1 de Hormônio Paratireóideo/genética , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Adolescente , Adulto , Animais , Células CHO , Células COS , Criança , Chlorocebus aethiops , Condroma/genética , Condroma/metabolismo , Condroma/fisiopatologia , Estudos de Coortes , Cricetinae , Cricetulus , AMP Cíclico/metabolismo , Encondromatose/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Hormônio Paratireóideo/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Receptor Tipo 1 de Hormônio Paratireóideo/química , Transdução de Sinais
15.
Am J Med Genet A ; 152A(12): 3124-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21082660

RESUMO

We describe a patient with striking generalized symmetrical enchondromatosis of the tubular bones and a de novo duplication of chromosome 12p11.23 to 12p11.22. The PTHLH gene within this region encodes a ligand for PTHR1: mutations in the gene encoding this receptor are associated with some cases of Ollier disease, several skeletal dysplasias including Blomstrand, Eiken, and Jansen and down-regulation of PTHLH expression in brachydactyly type E. Our findings suggest that abnormal PTHLH-PTHR1 signaling may underly this unusual form of enchondromatosis and indicate that unlike most cases of Ollier disease it is dominantly inherited.


Assuntos
Duplicação Cromossômica , Cromossomos Humanos Par 12 , Encondromatose/genética , Proteína Relacionada ao Hormônio Paratireóideo/genética , Adolescente , Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Doenças do Desenvolvimento Ósseo/genética , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Hibridização Genômica Comparativa , DNA/genética , Regulação para Baixo , Encondromatose/diagnóstico por imagem , Encondromatose/metabolismo , Feminino , Genes Dominantes , Humanos , Hibridização in Situ Fluorescente , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Radiografia , Receptor Tipo 1 de Hormônio Paratireóideo/genética , Transdução de Sinais/genética
16.
Exp Clin Endocrinol Diabetes ; 128(10): 681-686, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31860119

RESUMO

The PTH/PTHrP receptor (PTHR1) mediates the actions of parathyroid hormone (PTH) and PTH-related peptide (PTHrP) by coupling this G protein-coupled receptor (GPCR) to the alpha-subunit of the heterotrimeric stimulatory G protein (Gsα) and thereby to the formation of cAMP. In growth plates, PTHrP-dependent activation of the cAMP/PKA second messenger pathway prevents the premature differentiation of chondrocytes into hypertrophic cells resulting in delayed growth plate closure. Heterozygous mutations in GNAS, the gene encoding Gsα, lead to a reduction in cAMP levels in growth plate chondrocytes that is sufficient to cause shortening of metacarpals and/or -tarsals, i. e. typical skeletal aspects of Albright's Hereditary Osteodystrophy (AHO). However, heterozygous mutations in other genes, including those encoding PTHrP, PRKAR1A, PDE4D, and PDE3A, can lead to similar or even more pronounced acceleration of skeletal maturation that is particularly obvious in hands and feet, and reduces final adult height. Genetic mutations other than those resulting in Gsα haploinsufficiency thus reduce intracellular cAMP levels in growth plate chondrocytes to a similar extent and thereby accelerate skeletal maturation.


Assuntos
Condrócitos , Cromograninas/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dedos/anormalidades , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Lâmina de Crescimento/crescimento & desenvolvimento , Anormalidades Musculoesqueléticas/genética , Dedos do Pé/anormalidades , Condrócitos/citologia , Condrócitos/metabolismo , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Humanos , Proteína Relacionada ao Hormônio Paratireóideo/genética , Receptor Tipo 1 de Hormônio Paratireóideo/genética
17.
Case Rep Genet ; 2020: 8217919, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32832172

RESUMO

Amelogenesis imperfecta (AI) represents rare tooth anomalies that affect the quality and/or quantity of the enamel. Clinical phenotypes display a wide spectrum, ranging from mild color changes to severe structural alterations with daily pain. However, all affect the quality of life because of mechanical, psychological, esthetic, and/or social repercussions. Several gene mutations have been linked to AI as a nonsyndromic (isolated) phenotype or a wider syndrome. This case report aimed to present a family with dental structure anomalies followed up in the dental department of the Louis Mourier Hospital (APHP, France) for their extremely poor dental condition. The proband and his mother were clinically diagnosed with AI, and genetic analysis revealed an already described variant in DLX3. Then, the family was further examined for tricho-dento-osseous syndrome. This report illustrates the challenge of diagnosing dental structure anomalies, specifically AI, in adults and highlights the need for an accurate and accessible molecular diagnosis for those anomalies to discriminate between isolated and syndromic pathologies.

18.
J Bone Miner Res ; 35(7): 1263-1273, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32101626

RESUMO

X-linked hypophosphatemia (XLH) is characterized by increased activity of circulating FGF23 resulting in renal phosphate wasting and abnormal bone mineralization. Hyperparathyroidism may develop in XLH patients; however, its prevalence, pathogenesis, and clinical presentation are not documented. This observational study (CNIL 171036 v 0) recruited XLH adult patients in a single tertiary referral center. Each patient was explored in standardized conditions and compared with two healthy volunteers, matched for sex, age, and 25-OH vitamin D concentrations. The primary endpoint was the proportion of patients with hyperparathyroidism. The secondary endpoints were the factors influencing serum parathyroid hormone (PTH) concentrations and the prevalence of hypercalcemic hyperparathyroidism. Sixty-eight patients (51 women, 17 men) were enrolled and matched with 136 healthy volunteers. Patients had higher PTH concentrations compared with healthy controls (53.5 ng/L, interquartile range [IQR] 36.7-72.7 versus 36.0 ng/L, IQR 27.7-44.0, p < .0001). Hyperparathyroidism was observed in 17 patients of 68 (25%). In patients, a positive relationship between PTH and calcium concentrations and a negative relationship between PTH and phosphate concentrations were observed. Seven (10%) patients (3 premenopausal women, 1 postmenopausal woman, and 3 men) were diagnosed with hypercalcemic hyperparathyroidism. All underwent parathyroid surgery, with consecutive normalization of calcium and PTH concentrations. Hyperparathyroidism is a frequent complication in XLH adult patients. Disruption of the physiological regulation of PTH secretion contributes to parathyroid disease. Early-onset hypercalcemic hyperparathyroidism can be effectively and safely cured by surgical resection. © 2020 American Society for Bone and Mineral Research.


Assuntos
Raquitismo Hipofosfatêmico Familiar , Hiperparatireoidismo , Adulto , Cálcio , Raquitismo Hipofosfatêmico Familiar/complicações , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Hiperparatireoidismo/complicações , Hiperparatireoidismo/epidemiologia , Masculino , Hormônio Paratireóideo , Fosfatos , Vitamina D
19.
Horm Res Paediatr ; 93(3): 182-196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756064

RESUMO

Patients affected by pseudohypoparathyroidism (PHP) or related disorders are characterized by physical findings that may include brachydactyly, a short stature, a stocky build, early-onset obesity, ectopic ossifications, and neurodevelopmental deficits, as well as hormonal resistance most prominently to parathyroid hormone (PTH). In addition to these alterations, patients may develop other hormonal resistances, leading to overt or subclinical hypothyroidism, hypogonadism and growth hormone (GH) deficiency, impaired growth without measurable evidence for hormonal abnormalities, type 2 diabetes, and skeletal issues with potentially severe limitation of mobility. PHP and related disorders are primarily clinical diagnoses. Given the variability of the clinical, radiological, and biochemical presentation, establishment of the molecular diagnosis is of critical importance for patients. It facilitates management, including prevention of complications, screening and treatment of endocrine deficits, supportive measures, and appropriate genetic counselling. Based on the first international consensus statement for these disorders, this article provides an updated and ready-to-use tool to help physicians and patients outlining relevant interventions and their timing. A life-long coordinated and multidisciplinary approach is recommended, starting as far as possible in early infancy and continuing throughout adulthood with an appropriate and timely transition from pediatric to adult care.


Assuntos
Diabetes Mellitus Tipo 2 , Nanismo Hipofisário , Hipotireoidismo , Pseudo-Hipoparatireoidismo , Transição para Assistência do Adulto , Adulto , Criança , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Nanismo Hipofisário/diagnóstico , Nanismo Hipofisário/terapia , Humanos , Hipotireoidismo/diagnóstico , Hipotireoidismo/terapia , Guias de Prática Clínica como Assunto , Pseudo-Hipoparatireoidismo/diagnóstico , Pseudo-Hipoparatireoidismo/terapia
20.
Medicine (Baltimore) ; 98(50): e18102, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852070

RESUMO

RATIONALE: Intraductal papillary and mucinous neoplasms of the pancreas (IPMN) are preneoplastic lesions diagnosed with an increasing incidence. Recently, several groups have described, in up to 70% of IPMN, activating mutations of the G-protein alpha stimulatory sub-unit (Gsα subunit) gene (GNAS). GNAS-activating somatic, post-zygotic, mutations are also associated with McCune-Albright syndrome (MCAS) characterized by fibrous dysplasia, precocious puberty, and café-au-lait spots. PATIENT CONCERNS: We herein report a patient with McCune Albright Syndrome that presented with malignant IPMN and underwent pancreatic resection. DIAGNOSES AND INTERVENTIONS: Leucocyte and duodenum juice DNA analysis, endoscopically collected from secretin-stimulated pancreatic juice revealed the same (GNAS) activating mutation also found in the invasive pancreatic colloid adenocarcinoma arising from intestinal subtype IPMN. OUTCOMES: Thirty months after surgery, the patient was alive with recurrence (bone only metastasis). LESSONS: In this observation, we show that MCAS should be view as a new genetic predisposition to IPMN associated pancreatic cancer, and consequently a targeted screening in this high-risk population might be proposed.


Assuntos
Adenocarcinoma Mucinoso/genética , Carcinoma Ductal Pancreático/genética , Cromograninas/genética , Displasia Fibrosa Poliostótica/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Predisposição Genética para Doença , Mutação , Neoplasias Pancreáticas/genética , Adenocarcinoma Mucinoso/diagnóstico , Adenocarcinoma Mucinoso/etiologia , Biópsia por Agulha , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/etiologia , Cromograninas/metabolismo , Análise Mutacional de DNA , DNA de Neoplasias/genética , Endossonografia , Feminino , Displasia Fibrosa Poliostótica/complicações , Displasia Fibrosa Poliostótica/diagnóstico , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Humanos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/etiologia , Tomografia Computadorizada por Raios X
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