Search Results

You are looking at 1 - 4 of 4 items for

  • Author: Georgios Papadakis x
Clear All Modify Search
Free access

Ricardo Correa, Mihail Zilbermint, Annabel Berthon, Stephanie Espiard, Maria Batsis, Georgios Z Papadakis, Paraskevi Xekouki, Maya B Lodish, Jerome Bertherat, Fabio R Faucz and Constantine A Stratakis

Objective

Primary macronodular adrenal hyperplasia (PMAH) is a rare type of Cushing's syndrome (CS) that results in increased cortisol production and bilateral enlargement of the adrenal glands. Recent work showed that the disease may be caused by germline and somatic mutations in the ARMC5 gene, a likely tumor suppressor gene (TSG). We investigated 20 different adrenal nodules from one patient with PMAH for ARMC5 somatic sequence changes.

Design

All of the nodules were obtained from a single patient who underwent bilateral adrenalectomy. DNA was extracted by standard protocol and the ARMC5 sequence was determined by the Sanger method.

Results

Sixteen of 20 adrenocortical nodules harbored, in addition to what appeared to be the germline mutation, a second somatic variant. The p.Trp476* sequence change was present in all 20 nodules, as well as in normal tissue from the adrenal capsule, identifying it as the germline defect; each of the 16 other variants were found in different nodules: six were frame shift, four were missense, three were nonsense, and one was a splice site variation. Allelic losses were confirmed in two of the nodules.

Conclusion

This is the most genetic variance of the AR MC5 gene ever described in a single patient with PMAH: each of 16 adrenocortical nodules had a second new, ‘private,’ and – in most cases – completely inactivating ARMC5 defect, in addition to the germline mutation. The data support the notion that ARMC5 is a TSG that needs a second, somatic hit, to mediate tumorigenesis leading to polyclonal nodularity; however, the driver of this extensive genetic variance of the second ARMC5 allele in adrenocortical tissue in the context of a germline defect and PMAH remains a mystery.

Free access

Amit Tirosh, Georgios Z Papadakis, Corina Millo, Samira M Sadowski, Peter Herscovitch, Karel Pacak, Stephen J Marx, Lily Yang, Pavel Nockel, Jasmine Shell, Patience Green, Xavier M Keutgen, Dhaval Patel, Naris Nilubol and Electron Kebebew

Objective

To determine the association between neuroendocrine tumor (NET) biomarker levels and the extent of disease as assessed by 68Ga DOTATATE PET/CT imaging.

Design

A retrospective analysis of a prospective database of patients with NETs.

Methods

Fasting plasma chromogranin A (CgA), neuron-specific enolase (NSE), gastrin, glucagon, vasoactive intestinal peptide (VIP) and pancreatic polypeptide (PP), and 24-h urinary 5-hydroxyindoleacetic acid (5-HIAA) levels were measured. Correlation between biomarkers and total 68Ga-DOTATATE-avid tumor volume (TV) was analyzed.

Results

The analysis included 232 patients. In patients with pancreatic NETs (n = 112), 68Ga-DOTATATE TV correlated with CgA (r = 0.6, P = 0.001, Spearman). In patients with multiple endocrine neoplasia type 1 (n = 39), 68Ga-DOTATATE TV correlated with glucagon (r = 0.5, P = 0.01) and PP levels (r = 0.5, P = 0.049). In patients with von Hippel–Lindau (n = 24), plasma VIP (r = 0.5, P = 0.02) and PP levels (r = 0.7, P < 0.001) correlated with 68Ga-DOTATATE TV. In patients with small intestine NET (SINET, n = 74), 68Ga-DOTATATE TV correlated with CgA (r = 0.5, P = 0.02) and 5-HIAA levels (r = 0.7, P < 0.001), with 5-HIAA ≥8.1 mg/24 h associated with metastatic disease with high positive (81.8%) and negative (85.7%) predictive values (P = 0.001). 68Ga-DOTATATE TV in patients with NET of unknown primary (n = 16) and those with NET of other primary location (n = 30) correlated with 5-HIAA levels (r = 0.8, P = 0.002 and r = 0.7, P = 0.02 respectively).

Conclusions

Our data supports the use of specific NET biomarkers based on the site of the primary NET and the presence of hereditary syndrome-associated NET. High urinary 5-HIAA levels indicate the presence of metastatic disease in patients with SINET.

Restricted access

Luigi Maione, Giovanna Pala, Claire Bouvattier, Séverine Trabado, Georgios Papadakis, Philippe Chanson, Jérôme Bouligand, Nelly Pitteloud, Andrew A Dwyer, Mohamad Maghnie and Jacques Young

Context

Congenital hypogonadotropic hypogonadism/Kallmann syndrome (CHH/KS) is a rare condition characterized by gonadotropin deficiency and pubertal failure. Adult height (AH) in patients with CHH/KS has not been well studied.

Objective

To assess AH in a large cohort of patients with CHH/KS.

Patients

A total of 219 patients (165 males, 54 females). Parents and siblings were included.

Methods

AH was assessed in patients and family members. AH was compared to the general French population, mid parental target height (TH) and between patients and same-sex siblings. Delta height (∆H) was considered as the difference between AH and parental TH. ∆H was compared between patients and siblings, normosmic CHH and KS (CHH with anosmia/hyposmia), and according to underlying genetic defect. We examined the correlations between ∆H and age at diagnosis and therapeutically induced individual statural gain.

Results

Mean AH in men and women with CHH/KS was greater than that in the French general population. Patients of both sexes had AH > TH. Males with CHH/KS were significantly, albeit moderately, taller than their brothers. ∆H was higher in CHH/KS compared to unaffected siblings (+6.2 ± 7.2 cm vs +3.4 ± 5.2 cm, P < 0.0001). ∆H was positively correlated with age at diagnosis. Neither olfactory function (normosmic CHH vs KS) nor specific genetic cause impacted ∆H. Individual growth during replacement therapy inversely correlated with the age at initiation of hormonal treatment (P < 0.0001).

Conclusions

CHH/KS is associated with higher AH compared to the general population and mid-parental TH. Greater height in CHH/KS than siblings indicates that those differences are in part independent of an intergenerational effect.

Open access

Daniele Cassatella, Sasha R Howard, James S Acierno, Cheng Xu, Georgios E Papadakis, Federico A Santoni, Andrew A Dwyer, Sara Santini, Gerasimos P Sykiotis, Caroline Chambion, Jenny Meylan, Laura Marino, Lucie Favre, Jiankang Li, Xuanzhu Liu, Jianguo Zhang, Pierre-Marc Bouloux, Christian De Geyter, Anne De Paepe, Waljit S Dhillo, Jean-Marc Ferrara, Michael Hauschild, Mariarosaria Lang-Muritano, Johannes R Lemke, Christa Flück, Attila Nemeth, Franziska Phan-Hug, Duarte Pignatelli, Vera Popovic, Sandra Pekic, Richard Quinton, Gabor Szinnai, Dagmar l’Allemand, Daniel Konrad, Saba Sharif, Özlem Turhan Iyidir, Brian J Stevenson, Huanming Yang, Leo Dunkel and Nelly Pitteloud

Objective

Congenital hypogonadotropic hypogonadism (CHH) and constitutional delay of growth and puberty (CDGP) represent rare and common forms of GnRH deficiency, respectively. Both CDGP and CHH present with delayed puberty, and the distinction between these two entities during early adolescence is challenging. More than 30 genes have been implicated in CHH, while the genetic basis of CDGP is poorly understood.

Design

We characterized and compared the genetic architectures of CHH and CDGP, to test the hypothesis of a shared genetic basis between these disorders.

Methods

Exome sequencing data were used to identify rare variants in known genes in CHH (n = 116), CDGP (n = 72) and control cohorts (n = 36 874 ExAC and n = 405 CoLaus).

Results

Mutations in at least one CHH gene were found in 51% of CHH probands, which is significantly higher than in CDGP (7%, P = 7.6 × 10−11) or controls (18%, P = 5.5 × 10−12). Similarly, oligogenicity (defined as mutations in more than one gene) was common in CHH patients (15%) relative to CDGP (1.4%, P = 0.002) and controls (2%, P = 6.4 × 10−7).

Conclusions

Our data suggest that CDGP and CHH have distinct genetic profiles, and this finding may facilitate the differential diagnosis in patients presenting with delayed puberty.