Browsing by Subject "Acromegaly"

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    Germline loss-of-function PAM variants are enriched in subjects with pituitary hypersecretion
    (Cold Spring Harbor Laboratory, 2023-01-20) Trivellin, Giampaolo; Daly, Adrian F.; Hernández-Ramírez, Laura C.; Araldi, Elisa; Tatsi, Christina; Dale, Ryan K.; Fridell, Gus; Mittal, Arjun; Faucz, Fabio R.; Iben, James R.; Li, Tianwei; Vitali, Eleonora; Stojilkovic, Stanko S.; Kamenicky, Peter; Villa, Chiara; Baussart, Bertrand; Chittiboina, Prashant; Toro, Camilo; Gahl, William A.; Eugster, Erica A.; Naves, Luciana A.; Jaffrain-Rea, Marie-Lise; de Herder, Wouter W.; Neggers, Sebastian Jcmm; Petrossians, Patrick; Beckers, Albert; Lania, Andrea G.; Mains, Richard E.; Eipper, Betty A.; Stratakis, Constantine A.; Pediatrics, School of Medicine
    Pituitary adenomas (PAs) are common, usually benign tumors of the anterior pituitary gland which, for the most part, have no known genetic cause. PAs are associated with major clinical effects due to hormonal dysregulation and tumoral impingement on vital brain structures. Following the identification of a loss-of-function variant (p.Arg703Gln) in the PAM gene in a family with pituitary gigantism, we investigated 299 individuals with sporadic PAs and 17 familial isolated pituitary adenomas kindreds for PAM variants. PAM encodes a multifunctional protein responsible for the essential C-terminal amidation of secreted peptides. Genetic screening was performed by germline and tumor sequencing and germline copy number variation (CNV) analysis. No germline CNVs or somatic single nucleotide variants (SNVs) were identified. We detected seven likely pathogenic heterozygous missense, truncating, and regulatory SNVs. These SNVs were found in sporadic subjects with GH excess (p.Gly552Arg and p.Phe759Ser), pediatric Cushing disease (c.−133T>C and p.His778fs), or with different types of PAs (c.−361G>A, p.Ser539Trp, and p.Asp563Gly). The SNVs were functionally tested in vitro for protein expression and trafficking by Western blotting, for splicing by minigene assays, and for amidation activity in cell lysates and serum samples. These analyses confirmed a deleterious effect on protein expression and/or function. By interrogating 200,000 exomes from the UK Biobank, we confirmed a significant association of the PAM gene and rare PAM SNVs to diagnoses linked to pituitary gland hyperfunction. Identification of PAM as a candidate gene associated with pituitary hypersecretion opens the possibility of developing novel therapeutics based on altering PAM function.
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    McCune-Albright syndrome and the extraskeletal manifestations of fibrous dysplasia
    (Springer Nature, 2012) Collins, Michael T.; Singer, Frederick R.; Eugster, Erica; Pediatrics, School of Medicine
    Fibrous dysplasia (FD) is sometimes accompanied by extraskeletal manifestations that can include any combination of café-au-lait macules, hyperfunctioning endocrinopathies, such as gonadotropin-independent precocious puberty, hyperthyroidism, growth hormone excess, FGF23-mediated renal phosphate wasting, and/or Cushing syndrome, as well as other less common features. The combination of any of these findings, with or without FD, is known as McCune-Albright syndrome (MAS). The broad spectrum of involved tissues and the unpredictable combination of findings owe to the fact that molecular defect is due to dominant activating mutations in the widely expressed signaling protein, Gsα, and the fact these mutations arises sporadically, often times early in development, prior to gastrulation, and can distribute across many or few tissues.The complexity can be mastered by a systematic screening of potentially involved tissues and cognizance that the pattern of involved tissues is established, to some degree, in utero. Thorough testing allows the clinician to establish, often times at presentation, the full extent of the disease, and importantly as well what tissues are unaffected. Treatment and follow-up can then be focused on affected systems and a meaningful prognosis can be offered to the patient and family. The authors outline screening and treatment strategies that allow for effective management of the extraskeletal manifestations of FD.