Patient’s Atypical Cushing’s Symptoms Lead to Discovery of Novel Genetic Mutations

New genetic mutations were found in a patient who exhibited atypical symptoms of Cushing’s syndrome, notably an abnormal protrusion of the eye, a case report shows.

The research, “Extensive ARMC5 genetic variance in primary bilateral macronodular adrenal hyperplasia that started with exophthalmos: a case report,” was published in the Journal of Medical Case Reports.

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a disorder characterized by multiple lumps in the adrenal glands and excessive cortisol production. It is a rare cause of Cushing’s syndrome.

According to recent research, PBMAH is caused by mutations in the ARMC5 gene, which data suggest may act as a tumor suppressor.

Researchers presented the case of a 52-year-old Chinese woman who exhibited a protrusion of both eyes (exophtalmos), which was first thought to be Graves’ ophthalmopathy. An injection of triamcinolone acetonide, a corticosteroid, into the area behind the eye globe did not improve symptoms.

The patient later was diagnosed with diabetes, which was treated with insulin, and hypertension, treated with insulin and amlodipine. She also developed muscle weakness and bruised easily. She had no other relevant chronic illness or infectious disease, and did not smoke tobacco or drink alcohol.

Physical examination showed skin atrophy, moon face, buffalo hump (between the shoulders), and purplish abdominal striae (stretch marks), which researchers defined as a typical Cushingoid appearance. The patient also experienced elevated pressure inside the eye, and had edema, conjunctival congestion, and lid retraction. No liver, spleen, respiration, cardiac, abdominal, blood counts, urinary, sensory, or motor abnormalities were noted.

Biochemical evaluation showed elevated cortisol and reduced adrenocorticotropin (ACTH) levels. Administering  dexamethasone did not lower the level of cortisol. Abnormal responses of the hormone vasopressin also were detected.

A computed tomography (CT) scan of the adrenal glands showed bilateral multiple lobular masses, and an MRI of the eye orbits indicated bilateral exophthalmos with hypertrophy of the retro-orbital fat, which lines the orbit.

After PBMAH was diagnosed, the patient’s adrenal glands were removed. Pathological findings showed multiple, homogenous, golden-yellow-colored nodules on the glands.

The surgery successfully lowered the level of cortisol and increased that of ACTH. The patient began taking hydrocortisone and metformin for diabetes. After six months, her exophtlamos, blood glucose levels, and blood pressure had improved.

Genetic analysis revealed six specific ARMC5 mutations in five of the seven adrenal nodules analyzed. “All the mutations are novel and not found in available online databases,” the researchers wrote. The mutations may lead to resistance to cell death in the tumor cells, and cause an increase in the production of cortisol, they observed.

As a result of the ARMC5 mutations, gene expression (conversion of genetic information) of the messenger RNA (mRNA, which is converted from DNA in the first step of protein synthesis) was lower in the adrenal tumor samples, in comparison with normal adrenal cortex.

Overall, the study “highlights the importance of early recognition of atypical symptoms of Cushing’s syndrome such as exophthalmos, which would save the patient from harmful effects of excessive cortisol exposure,” the researchers said. Screening for ARMC5 mutations also would help improve diagnosis and genetic counseling, they said.

From https://cushingsdiseasenews.com/2018/02/13/odd-cushings-symptoms-linked-genetic-mutations-case-report/

Patients with ARMC5 mutations: The NIH clinical experience

Screenshot 2016-05-27 13.12.55

 

Adrenal Disorders

R Correa, M Zilbermint, A Demidowich, F Faucz, A Berthon, J Bertherat, M Lodish, C Stratakis

Summary: Researchers conducted this study to describe the different phenotypical characteristics of patients with armadillo repeat containing 5 (ARMC5) mutations, located in 16p11.2 and a likely tumor-suppressor gene. They determined that patients with bilateral adrenal enlargement, found on imaging tests, should be screened for ARMC5 mutations, which are associated with subclinical Cushing’s syndrome (CS) and primary hyperaldosteronism (PA).

Methods:

  • Researchers identified 20 patients with ARMC5 mutations (germline and/or somatic) who were enrolled in a National Institutes of Health (NIH) protocol.
  • They obtained sociodemographic, clinical, laboratory, and radiological data for all participants.

Results:

  • Three families (with a total of 8 patients) were identified with ARMC5 germline mutations; the rest of the patients (13/20) had sporadic mutations.
  • The male to female ratio was 1.2:1; mean age was 48 years and 60% of patients were African American.
  • Forty percent of patients were diagnosed with CS, 20% with subclinical CS, 30% with hyperaldosteronism, and 10% had no diagnosis.
  • The mean serum cortisol (8 am) and Urinary Free Cortisol were 13.1 mcg/dl and 77 mcg/24 hours, respectively.
  • Nearly all patients (95%) had bilateral adrenal enlargement found on CT or MRI.
  • Patients underwent the following treatments: Bilateral adrenalectomy (45%), unilateral adrenalectomy (25%), medical treatment (20%), and no treatment (10%).
  • ARMC5 mutations are associated with primary macronodular adrenal hyperplasia (PMAH) and are also seen in patients with PA, especially among African Americans.

From http://www.mdlinx.com/endocrinology/conference-abstract.cfm/ZZ37C4C5D3BF1A4FAE9C479A696660535B/57884/?utm_source=confcoveragenl&utm_medium=newsletter&utm_content=abstract-list&utm_campaign=abstract-AACE2016&nonus=0

Mutation of ARMC5 gene characterized as the cause of meningeal tumour growth

Scientists at the Luxembourg Centre for Systems Biomedicine (LCSB) of the University of Luxembourg have published their findings that mutations in a gene known as “ARMC5” promote the growth of benign tumours in the adrenal glands and on the meninges: ARMC5 appears to belong to the group of so-called tumour suppressor genes. It is the first time in years that scientists have characterized such a gene.

The ARMC5 gene was discovered by independent workgroups studying – so-called adrenal adenomas – in connection with Cushing’s syndrome. In this disease, the body produces too much of the . Now, for the first time, a mutation of ARMC5 has been characterized as the cause behind the growth of meningeal tumours. The results on this tumour syndrome, obtained by the group of Dr. Patrick May and PD. Dr. Jochen Schneider together with colleagues from CharitĂ© Berlin (Dr. Ulf Elbelt) and the Universities of WĂĽrzburg (Prof. Dr. Bruno Allolio) and Cologne (Dr. Michael Kloth), have been published recently in the Journal of Clinical Endocrinology Metabolism.

Cortisol is an important hormone. It influences many metabolic pathways in the body and has a suppressing effect on the immune system. Accordingly, it is commonly employed as an anti-inflammatory medication. Prolonged, elevated levels of cortisol in the body can lead to obesity, muscular dystrophy, depression and other symptoms. To maintain the correct concentration in the blood, the body has a refined regulation system: Certain areas of the brain produce the hormone corticotropin as a stimulator of cortisol release; the actual formation of cortisol takes place in the . As the concentration of cortisol in the blood rises, the brain reduces the production of corticotropin.

In search of the causes of Cushing’s syndrome, scientists recently encountered certain genetic causes of benign tumours of the adrenal cortex. Growth of these adrenal cortex adenomas is based on a combination of hereditary and spontaneous mutations: It affects people in whom one of two “alternative copies” – one of the so-called alleles – of the ARMC5 gene is mutated from birth. If the second allele of ARMC5 later also undergoes a spontaneous mutation in the adrenal cortex, then the gene no longer functions. “What is interesting is that the failure of ARMC5 has no direct influence on cortisol production. However, because the tumour cells multiply faster than other body cells, and the number of cells in the tumour increases, the blood cortisol level rises in the course of the disease”, says Dr Schneider. Then, the level in the body rises and ultimately results in the onset of Cushing’s syndrome.

When other scientific workgroups discovered that further benign tumours – in this case meningeal tumours – occur more often in ARMC5-Cushing families, the group of Patrick May and Jochen Schneider sequenced the ARMC5 gene and studied it using bioinformatic techniques. “We demonstrated for the first time, in a patient with an adrenal cortex tumour and simultaneously a meningeal tumour, that somatic, that is non-hereditary, ARMC5 mutations are present in both tumours. This observation suggests that ARMC5 is a true tumour-suppressor gene.”

It must now be explored, Schneider continues, to what extent patients with adrenal cortex tumours ought to be screened for simultaneous presence of meningioma, and in which other types of tumour ARMC5 mutations are responsible for tumour growth: “Building upon that, we can learn whether the gene and the metabolic pathways it influences offer new approaches for treating the tumour syndrome.”

More information: “Molecular and Clinical Evidence for an ARMC5 Tumor Syndrome: Concurrent Inactivating Germline and Somatic Mutations are Associated with both Primary Macronodular Adrenal Hyperplasia and Meningioma.” Journal of Clinical Endocrinology Metabolism, October 2014. DOI: 10.1210/jc.2014-2648

Journal reference: Journal of Clinical Endocrinology & Metabolism search and more info website

Provided by University of Luxembourg search and more info

From http://medicalxpress.com/news/2014-10-mutation-armc5-gene-characterized-meningeal.html

ARMC5 Mutations in Macronodular Adrenal Hyperplasia with Cushing’s Syndrome

adrenal-hyperplasia

 

Guillaume Assié, M.D., Ph.D., Rossella Libé, M.D., Stéphanie Espiard, M.D., Marthe Rizk-Rabin, Ph.D., Anne Guimier, M.D., Windy Luscap, M.Sc., Olivia Barreau, M.D., Lucile Lefèvre, M.Sc., Mathilde Sibony, M.D., Laurence Guignat, M.D., Stéphanie Rodriguez, M.Sc., Karine Perlemoine, B.S., Fernande René-Corail, B.S., Franck Letourneur, Ph.D., Bilal Trabulsi, M.D., Alix Poussier, M.D., Nathalie Chabbert-Buffet, M.D., Ph.D., Françoise Borson-Chazot, M.D., Ph.D., Lionel Groussin, M.D., Ph.D., Xavier Bertagna, M.D., Constantine A. Stratakis, M.D., Ph.D., Bruno Ragazzon, Ph.D., and Jérôme Bertherat, M.D., Ph.D.

N Engl J Med 2013; 369:2105-2114 November 28, 2013 DOI: 10.1056/NEJMoa1304603

BACKGROUND

Corticotropin-independent macronodular adrenal hyperplasia may be an incidental finding or it may be identified during evaluation for Cushing’s syndrome. Reports of familial cases and the involvement of both adrenal glands suggest a genetic origin of this condition.

METHODS

We genotyped blood and tumor DNA obtained from 33 patients with corticotropin-independent macronodular adrenal hyperplasia (12 men and 21 women who were 30 to 73 years of age), using single-nucleotide polymorphism arrays, microsatellite markers, and whole-genome and Sanger sequencing. The effects of armadillo repeat containing 5 (ARMC5) inactivation and overexpression were tested in cell-culture models.

RESULTS

The most frequent somatic chromosome alteration was loss of heterozygosity at 16p (in 8 of 33 patients for whom data were available [24%]). The most frequent mutation identified by means of whole-genome sequencing was in ARMC5, located at 16p11.2. ARMC5 mutations were detected in tumors obtained from 18 of 33 patients (55%). In all cases, both alleles of ARMC5 carried mutations: one germline and the other somatic. In 4 patients with a germline ARMC5 mutation, different nodules from the affected adrenals harbored different secondary ARMC5 alterations. Transcriptome-based classification of corticotropin-independent macronodular adrenal hyperplasia indicated that ARMC5 mutations influenced gene expression, since all cases with mutations clustered together. ARMC5 inactivation decreased steroidogenesis in vitro, and its overexpression altered cell survival.

CONCLUSIONS

Some cases of corticotropin-independent macronodular adrenal hyperplasia appear to be genetic, most often with inactivating mutations of ARMC5, a putative tumor-suppressor gene. Genetic testing for this condition, which often has a long and insidious prediagnostic course, might result in earlier identification and better management. (Funded by Agence Nationale de la Recherche and others.)

Supported in part by grants from Agence Nationale de la Recherche (ANR-10-Blan-1136), CorticomedullosurrĂ©nale Tumeur Endocrine Network (Programme Hospitalier de Recherche Clinique grant AOM95201), Assistance Publique–HĂ´pitaux de Paris (Clinical Research Center Grant Genhyper P061006), Institut National du Cancer (Recherche Translationelle 2009-RT-02), the Seventh Framework Program of the European Commission (F2-2010-259735), INSERM (Contrat d’Interface, to Dr. AssiĂ©), the Conny-Maeva Charitable Foundation, and the intramural program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.

Drs. Assié, Libé, Espiard, Rizk-Rabin, Ragazzon, and Bertherat contributed equally to this article.

We thank Drs. J. Chelly and M. Delpech of the cell bank of Cochin Hospital and Dr. B. Terris of the tumor bank of Cochin Hospital for their help in sample collection; Dr. E. Clauser of the oncogenetic unit of Cochin Hospital for help in microsatellite analysis; Drs. J. Guibourdenche and E. Clauser of the hormone biology unit of Cochin Hospital for cortisol assays; Drs. F. Tissier and Pierre Colin for pathological analysis; Anne Audebourg for technical assistance; J. Metral and A. de Reynies of the Cartes d’IdentitĂ© des Tumeurs program of Ligue Nationale contre le Cancer for help in genomics studies and fruitful discussions; Dr. P. Nietschke of the bioinformatics platforms of Paris Descartes University for helpful discussions; all the members of the Genomics and Signaling of Endocrine Tumors team and of the genomic platform of Cochin Institute for their help in these studies; and the patients and their families, as well as the physicians and staff involved in patient care, for their active participation.

SOURCE INFORMATION

From INSERM Unité 1016, Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut Cochin (G.A., R.L., S.E., M.R.-R., A.G., W.L., O.B., L.L., S.R., K.P., F.R.-C., F.L., L. Groussin, X.B., B.R., J.B.), Faculté de Médecine Paris Descartes, Université Paris Descartes, Sorbonne Paris Cité (G.A., S.E., A.G., O.B., L.L., M.S., K.P., F.R.-C., L. Groussin, X.B., J.B.), Department of Endocrinology, Referral Center for Rare Adrenal Diseases (G.A., R.L., O.B., L. Guignat, L. Groussin, X.B., J.B.), and Department of Pathology (M.S.), Assistance Publique–Hôpitaux de Paris, Hôpital Cochin, and Unit of Endocrinology, Department of Obstetrics and Gynecology, Hôpital Tenon (N.C.-B.) — all in Paris; Unit of Endocrinology, Centre Hospitalier du Centre Bretagne, Site de Kério, Noyal-Pontivy (B.T.), Unit of Endocrinology, Hôtel Dieu du Creusot, Le Creusot (A.P.), and Department of Endocrinology Lyon-Est, Groupement Hospitalier Est, Bron (F.B.-C.) — all in France; and the Section on Endocrinology and Genetics, Program on Developmental Endocrinology and Genetics and the Pediatric Endocrinology Inter-Institute Training Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD (C.A.S.).

Address reprint requests to Dr. Bertherat at Service des Maladies Endocriniennes et Métaboliques, Centre de Référence des Maladies Rares de la Surrénale, Hôpital Cochin, 27 rue du Faubourg St. Jacques, 75014 Paris, France, or at jerome.bertherat@cch.aphp.fr.

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