Search Results

You are looking at 1 - 2 of 2 items for

  • Author: Anne Dib x
Clear All Modify Search
Restricted access

Philippe Chanson, Anne Dib, André Visot and Patrick J Derome

Chanson P, Dib A, Visot A, Derome PJ. McCune–Albright syndrome and acromegaly: clinical studies and responses to treatment in five cases. Eur J Endocrinol 1994;131:229–34. ISSN 0804–4643

We report here five new patients with McCune–Albright syndrome and acromegaly. In the five patients studied (three males and two females aged 19–42 years), acromegaly began before the age of 20 years and was recognized after the diagnosis of fibrous dysplasia, which was polyostotic in three cases and monostotic in two. Bone fibrous dysplasia always involved the base of the skull and in four patients prevented surgical removal of the pituitary adenoma, which was visualized easily by magnetic resonance imaging. Serum growth hormone (GH) levels ranged between 20 and 48 μg/l and were not suppressed by an oral glucose load. Thyrotropin-releasing hormone administration produced a paradoxical increase in serum GH levels in all the patients. Four of the five patients had hyperprolactinemia (43–670 μg/l). In the sole patient who could be operated on, a typical adenoma with positive immunostaining for GH was incompletely removed and postoperative radiation therapy failed to cure the acromegaly. In two patients, medical therapy with bromocriptine and/or octreotide was partially or totally ineffective whatever the dose (up to 1.5 mg per day) and duration (2–4 years) of octreotide treatment.

Philippe Chanson, Service d'Endocrinologie et Maladies de la Reproduction, Hôpital Bicêtre, F94275 Le Kremlin-Bicêtre, France

Restricted access

Christine Gicquel, Anne Dib, Xavier Bertagna, Serge Amselem and Yves Le Bouc

Gicquel C, Dib A, Bertagna X, Amselem S, Le Bouc Y. Oncogenic mutations of α-Gi2 protein are not determinant for human adrenocortical tumourigenesis. Eur J Endocrinol 1995:133:166–72. ISSN 0804–4643

Activating mutations of G proteins, which are membrane signal transducers, have been associated recently with the development of various endocrine neoplasms. Mutations of two highly conserved codons, Arg201 and Gin227, in the α-subunit of the Gs protein, the adenylyl cyclase-stimulating protein, were first described in growth hormone-producing pituitary tumours. They resulted in constitutive activation of the αs-subunit by decreasing intrinsic GTPase activity. A similar mutation, affecting codon Arg179 (exon 5) in the α-subunit of the Gi2 protein, the adenylyl cyclase-inhibiting protein, has been described by a single group in ovarian and adrenocortical tumours. We evaluated the frequency of activating mutations in the α-subunit of the Gi2 protein in 18 human adrenocortical tumours. We screened exons 5 (codon Arg179) and 6 (codon Gln205) for mutations by denaturing gradient gel electrophoresis analysis of leucocyte and tumoural DNA. No abnormal migration pattern was found in either exon. The absence of mutation in exon 5, which includes the Arg179 codon, was confirmed in all tumoural DNA by direct sequencing. In conclusion, we did not find any oncogenic mutations in the GTPase domain of the α-subunit of the Gi2 protein in adrenocortical tumours. Thus, the previously oncogenic gip2 mutations do not appear to be determinant for adrenocortical tumourigenesis.

Christine Gicquel, Laboratoire d'Explorations Fonctionnelles Endocriniennes, Hôpital Trousseau, 26 Avenue Arnold Netter, 75012 Paris, France