References of "Beckers, Albert"
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See detailGPR101 orphan GPCR: a novel cause of growth hormone deregulation
Abboud, Dayana ULiege; Daly, Adrian ULiege; Dupuis, Nadine ULiege et al

Poster (2017, May)

GPR101 is an orphan G-protein coupled receptor with unknown ligand. In 2014, an international study clearly pointed to a strong association between this receptor and the X-linked acrogigantism (X-LAG ... [more ▼]

GPR101 is an orphan G-protein coupled receptor with unknown ligand. In 2014, an international study clearly pointed to a strong association between this receptor and the X-linked acrogigantism (X-LAG) syndrome, which begins in childhood and causes the “tallest giants”. The children (carriers of the GPR101 duplication on the X chromosome) grow abnormally even before they are one year old, secrete phenomenal quantities of growth hormone, and develop pituitary adenomas that do not respond to current therapies. The mechanism by which GPR101 contributes to increased growth hormone secretion is currently not known. Nevertheless, the lack of mechanistic insight into the function of GPR101 precludes its validation as a drug target. This lack of knowledge on GPR101 is the consequence of the paucity of specific pharmacological/research tools currently available. Therefore, we propose to study GPR101 functions and its role in growth hormone regulation. First, we determined the receptor cellular localization. We also deciphered its constitutive signalling pathways by detecting high cAMP levels. We completed our study with an examination of receptor coupling to other pathways and G proteins. Furthermore, we applied targeted mutagenesis to modulate the receptor constitutive activity in order to understand the receptor function at a molecular level. These GPR101 mutants will help us to understand the role of this receptor in GH regulation and/or to treat people suffering from pituitary dysfunction. This information is an absolute prerequisite to link molecular pharmacology of GPR101 with physiological functions. [less ▲]

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See detailX-linked acrogigantism syndrome
Beckers, Albert ULiege

Scientific conference (2017, May)

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See detailLa déficience en hormone lutéinisante: ses conséquences sur la reproduction
VALDES SOCIN, Hernan Gonzalo ULiege; potorac, iulia; LIBIOULLE, Cécile ULiege et al

in Urologic (2017), 13(1), 18-23

En physiologie de la reproduction, il est bien établi que les hormones glycoprotéiques hypophysaires LH (hormone lutéinisante) et FSH régulent de concert la production de stéroïdes sexuels (indispensables ... [more ▼]

En physiologie de la reproduction, il est bien établi que les hormones glycoprotéiques hypophysaires LH (hormone lutéinisante) et FSH régulent de concert la production de stéroïdes sexuels (indispensables à la virilisation et à la féminisation) ainsi que la gamétogenèse (spermatogenèse chez l’homme et folliculogenèse chez la femme). La sécrétion des gonadotrophines hypophysaires est à son tour stimulée par quelque 1.500 neurones hypothalamiques à GnRH (gonadotrophin releasing hormone) et inhibée par la GnIH (gonadotrophin nhibitory hormone), récemment identifiée (1). En amont de la GnRH, un ensemble de neuropeptides hypothalamiques tels que les kisspeptines, la neuroquinine B, la dinorphine, la leptine, etc., modulent sa sécrétion (Figure 1). Ces neuropeptides intègrent les différents signaux internes et de l’environnement, nécessaires à la puberté et, par la suite, à la reproduction. En corollaire de ces données physiologiques, les patients porteurs de mutations invalidant les gènes de la GnRH, des neuropeptides décrits et de leurs récepteurs souffrent d’un hypogonadisme hypogonadotrope. Ces patients présentent un déficit plus ou moins sévère de la sécrétion combinée de LH et de FSH (2, 3). Il a fallu attendre des observations rares, telles que des mutations de la sous-unité beta (β) de l’hormone lutéinisante, pour comprendre la contribution spécifique et isolée de cette hormone à la reproduction. Dans cet article, nous synthétisons les données historiques et récentes sur la déficience en hormone lutéinisante et ses conséquences sur la reproduction. [less ▲]

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See detailX-LAG: How did they grow so tall?
BECKERS, Albert ULiege; Rostomyan, Liliya ULiege; Potorac, Iulia ULiege et al

in Annales d'Endocrinologie (2017)

X-linked acrogigantism (XLAG) is a new, pediatric-onset genetic syndrome, due to Xq26.3 microduplications encompassing the GPR101 gene. XLAG has a remarkably distinct phenotype with disease onset ... [more ▼]

X-linked acrogigantism (XLAG) is a new, pediatric-onset genetic syndrome, due to Xq26.3 microduplications encompassing the GPR101 gene. XLAG has a remarkably distinct phenotype with disease onset occurring before the age of 5 in all cases described to date, which is significantly younger than in other forms of pituitary gigantism. These patients have mixed GH and prolactin positive adenomas and/or mixed-cell hyperplasia and highly elevated levels of GH/IGF-1 and prolactin. Given their particularly young age of onset, the significant GH hypersecretion can lead to a phenotype of severe gigantism with very advanced age-specific height Z-scores. If not adequately treated in childhood, this condition results in extreme final adult height. XLAG has a clinical course that is highly similar to some of the tallest people with gigantism in history. « X-linked acrogigantism » (XLAG) est un syndrome pédiatrique récemment décrit, lié à des microduplications du chromosome Xq26.3, englobant le gène GPR101, responsable de l’affection. Les patients XLAG présentent un phénotype remarquablement distinct des autres cas de gigantisme hypophysaire. Dans tous les cas décrits, la maladie s’exprime avant 5 ans soit beaucoup plus tôt que dans les autres formes. Les patients ont habituellement un gros adénome ou une hyperplasie mixte pour la GH et la prolactine et des taux très élevés de GH/IGF1 et prolactine. En raison de son début très précoce, l’hypersécrétion importante de GH peut conduire à un gigantisme extrêmement sévère avec un Z-score très important pour l’âge. Si cette condition n’est pas traitée pendant l’enfance, elle peut conduire à une taille finale extrême. XLAG montre une évolution clinique similaire à celle observée chez les géants les plus grands de l’histoire. [less ▲]

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See detailComment on “Hypogonadotrophic hypogonadism due to a mutation in the luteinizing hormone β-subunit gene”
VALDES SOCIN, Hernan Gonzalo ULiege; Daly, Adrian ULiege; BECKERS, Albert ULiege

in Korean Journal of Internal Medicine (The) (2017), 32(3), 566-567

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See detailStable GPR101 over-Expressing Cell Lines As an Invaluable Tool for Functional Studies, Ligand Screening, and the Identification of Deregulated Genes/Pathways in Patients with X-Linked Acrogigantism
Trivellin, Giampaolo; Janjic, Maria; Larco, Darwin et al

Poster (2017, April 02)

Background: GPR101 is an orphan G protein-coupled receptor (GPCR) that is duplicated in patients with X-linked acrogigantism (X-LAG) and over-expressed in their GH- and PRL-secreting tumors. GPR101 is a ... [more ▼]

Background: GPR101 is an orphan G protein-coupled receptor (GPCR) that is duplicated in patients with X-linked acrogigantism (X-LAG) and over-expressed in their GH- and PRL-secreting tumors. GPR101 is a constitutively active GPCR that strongly activates the cAMP pathway. To elucidate the mechanisms through which GPR101 causes GH over-secretion we generated HEK293 and GH/PRL-secreting (GH3) cells with stable GPR101 expression. Methods: Both cell lines were created via direct integration of a human GPR101-coding sequence into their genome. In HEK293 cells this was achieved by transient transfection of a GPR101-expressing plasmid, while GH3 were transduced with GPR101 lentiviral particles. Cells were selected with appropriate antibiotics and the surviving clones expanded. GPR101 expression was quantified by RT-qPCR and immunofluorescence/western blotting. Cell proliferation (MTT assay), cAMP levels (125I-labeled cAMP tracer), and calcium signaling (FURA 2 AM) were determined. RNA was extracted from both cell lines and subjected to RNA-seq. Differential gene expression between control and GPR101-expressing cells and pathway analysis was carried out with the Stirplate and MetaCore softwares, respectively. De-regulated genes were validated by RT-qPCR. Results: High GPR101 expression was achieved in both cell lines and confirmed at the mRNA and protein level. GPR101-expressing cells proliferated at different rates from the respective controls: GPR101-HEK293 cells were slow-dividing, while GPR101-GH3 divided faster. cAMP production was enhanced in GPR101-GH3 and accompained by increased excitability of cells. Differential expression analysis in HEK293 cells revealed several up-regulated and few down-regulated genes. Among the genes with high expression, several were linked to the cAMP pathway: CGA, PCK1, LINC00473 and PDE3A. Enrichment analysis ranked cytoskeleton remodeling and cell cycle regulation (inhibition of G1/S transition) as the most relevant pathways. In GH3 cells most of the genes with a significantly different expression encoded for membrane-localized proteins, among which were ion channels (Trpm8, Kcnj1), GPCRs (Trhr), and calcium sensors (Syt4, Anxa1). Biological processes associated with these genes are: vesicle transport and fusion, cytoskeleton organization, and energy homeostasis. Conclusions: These results show that the intrinsic activity of GPR101 strongly stimulates cAMP production and this in turn facilitates voltage-gated calcium influx. Changes in cAMP/calcium signaling are accompanied with faster/slower cell division depending on the cell type. Accordingly, several genes associated with these and related pathways are differentially expressed. The establishment of these cell lines will be of paramount importance to validate putative GPR101 ligands and to conduct functional studies. [less ▲]

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See detailPrimary hypertrophic osteoarthropathy due to a novel SLCO2A1 mutation masquerading as acromegaly
Mangupli, Ruth; Daly, Adrian ULiege; Cuauro, Elvia et al

in Endocrinology, Diabetes and Metabolism Case Reports (2017)

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See detailHow the became the tallest of the world
Beckers, Albert ULiege

Scientific conference (2017, March 09)

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See detailGenetics of Pituitary Tumor Syndromes
Daly, Adrian ULiege; BECKERS, Albert ULiege

in Melmed, Shlomo (Ed.) The Pituitary (2017)

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See detailPaleogenetic study of ancient DNA suggestive of X-Linked acrogigantism
Beckers, Albert ULiege; Fernandes, Daniel; Fina, Frederic et al

in Endocrine-Related Cancer (2017)

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See detailSomatic mosaicism is implicated in the etiology of XLAG syndrome
Rostomyan, Liliya ULiege; Daly, Adrian ULiege; Yuan, Bo et al

in Abstract book : Symposium "Perspectives in Endocrinology" (2017, January)

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See detailGenetic predisposition to breast cancer occuring in a male-to-female transsexual patient
Potorac, Iulia ULiege; CORMAN, Vinciane ULiege; Manto, Florence ULiege et al

in Abstract book : Symposium "Perspectives in Endocrinology" (2017, January)

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See detailThe road from the adenoma valley through the forest of genetic testing in pituitary adenoma
Beckers, Albert ULiege

Scientific conference (2017, January)

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See detailHow to recognize Cowden syndrome: A novel PTEN mutation description.
Delannoy, Pauline; Debray, François-Guillaume ULiege; Verloes, Alain et al

in Annales d'Endocrinologie (2017)

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See detailTekort aan luteïniserend hormoon : gevolgen voor de voortplanting
VALDES SOCIN, Hernan Gonzalo ULiege; NECHIFOR, Iulia ULiege; LIBIOULLE, Cécile ULiege et al

in Bloedvaten, Hart, Longen (2017), 22(9),

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See detailLa déficience en hormone lutéinisante (LH) : ses conséquences sur la reproduction
VALDES SOCIN, Hernan Gonzalo ULiege; NECHIFOR, Iulia ULiege; LIBIOULLE, Cécile ULiege et al

in Vaisseaux, Coeur, Poumons (2017), 22(9),

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See detailUse of cinacalcet and sunitinib to treat hypercalcaemia due to a pancreatic neuroendocrine tumor.
VALDES SOCIN, Hernan Gonzalo ULiege; Almanza, Matilde Rubio; Fernandez-Ladreda, Mariana Tome et al

in Archives of Endocrinology and Metabolism (2017)

Neuroendocrine tumors (NETs) can secrete hormones, including ectopic secretions, but they have been rarely associated with malignant hypercalcemia. A 52-year-old man with a history of diabetes mellitus ... [more ▼]

Neuroendocrine tumors (NETs) can secrete hormones, including ectopic secretions, but they have been rarely associated with malignant hypercalcemia. A 52-year-old man with a history of diabetes mellitus was diagnosed with a pancreatic tumor. A pancreatic biopsy confirmed a well-differentiated pancreatic NET (pNET). The patient subsequently developed liver metastasis and hypercalcemia with high 1,25 OH vitamin D and suppressed parathyroid hormone (PTH) levels. Hypercalcemia was refractory to chemotherapy, intravenous saline fluids, diuretics, calcitonin and zoledronate. Cinacalcet administration (120 mg/day) resulted in a significant calcium reduction. Hypocalcemia was observed when sunitinib was added three months later and cinacalcet was stopped. Subsequently, the calcium and PTH levels normalized. After six months, we observed 20% shrinkage of the pancreatic tumor and necrosis of a liver metastasis. Cinacalcet is an allosteric activator of the calcium receptor agonist, and it is used for severe hypercalcemia in patients with primary (benign and malignant) hyperparathyroidism. In this patient, cinacalcet demonstrated a calcium lowering effect, normalized hypophosphatemia, and improved the clinical condition of the patient. The mechanism through which cinacalcet improved PTH-rp mediated hypercalcemia is still unclear, but studies have suggested that a potential mechanism is the activation of calcitonin secretion. Sunitinib is an oral multi-targeted tyrosine kinase inhibitor used to treat advanced pNETs. The hypocalcemic effects of sunitinib have not been previously described in a patient with pNET. Here, we report for the first time the successful combination of cinacalcet and sunitinib in the treatment of a pNET patient presenting with malignant hypercalcemia. [less ▲]

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See detailLa déficience en FSH : actualités cliniques et thérapeutiques
VALDES SOCIN, Hernan Gonzalo ULiege; Pintiaux, Axelle ULiege; Delbaere, Anne et al

in Urologic (2017), 13(3), 16-22

L'hormone lutéinisante (LH) et l'hormone folliculostimulante (FSH) - hormones glycoprotéiques hypophysaires - régulent de concert la production de stéroïdes sexuels et la reproduction. Les stéroïdes ... [more ▼]

L'hormone lutéinisante (LH) et l'hormone folliculostimulante (FSH) - hormones glycoprotéiques hypophysaires - régulent de concert la production de stéroïdes sexuels et la reproduction. Les stéroïdes sexuels sont indispensables à la virilisation et à la féminisation, et participent également à la gamétogenèse (spermatogenèse chez l'homme et folliculogenèse chez la femme). Cet article sur le déficit en FSH fait suite à un article précédent publié dans Urologic décrivant le déficit en LH et ses conséquences sur la reproduction. [less ▲]

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See detailHistologically Proven Bronchial Neuroendocrine Tumors in MEN1: A GTE 51-Case Cohort Study.
Lecomte, Pierre ULiege; Binquet, C.; Le Bras, M. et al

in World Journal of Surgery (2017)

OBJECTIVE: To evaluate the natural history of MEN1-related bronchial endocrine tumors (br-NETs) and to determine their histological characteristics, survival and causes of death. br-NETs frequency ranges ... [more ▼]

OBJECTIVE: To evaluate the natural history of MEN1-related bronchial endocrine tumors (br-NETs) and to determine their histological characteristics, survival and causes of death. br-NETs frequency ranges from 3 to 13% and may reach 32% depending on the number of patients evaluated and on the criteria required for diagnosis. METHODS: The 1023-patient series of symptomatic MEN1 patients followed up in a median of 48.7 [35.5-59.6] years by the Groupe d'etude des Tumeurs Endocrines was analyzed using time-to-event techniques. RESULTS: br-NETs were found in 51 patients (4.8%, [95% CI 3.6-6.2%]) and were discovered by imaging in 86% of cases (CT scan, Octreoscan, Chest X-ray, MRI). Median age at diagnosis was 45 years [28-66]. Histological examination showed 27 (53%) typical carcinoids (TC), 16 (31%) atypical carcinoids (AC), 2 (4%) large cell neuroendocrine carcinomas (LCNEC), 3(6%) small cell neuroendocrine carcinomas (SCLC), 3(6%) TC associated with AC. Overall survival was not different from the rest of the cohort (HR 0.29, [95% CI 0.02-5.14]). AC tended to have a worse prognosis than TC (p = 0.08). Seven deaths were directly related to br-NETs (three AC, three SCLC and one LCNEC). Patients who underwent surgery survived longer (p = 10-4) and were metastasis free, while 8 of 14 non-operated patients were metastatic. There were no operative deaths. CONCLUSIONS: Around 5% of MEN1 patients develop br-NETs. br-NETs do not decrease overall survival in MEN1 patients, but poorly differentiated and aggressive br-NETs can cause death. br-NETs must be screened carefully. A biopsy is essential to operate on patients in time. [less ▲]

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