Whole blood transcriptome signature predicts severe forms of COVID-19: Results from the COVIDeF cohort study.

COVID-19 is associated with heterogeneous outcome. Early identification of a severe progression of the disease is essential to properly manage the patients and improve their outcome. Biomarkers reflecting an increased inflammatory response, as well as individual features including advanced age, male gender, and pre-existing comorbidities, are risk factors of severe COVID-19. Yet, these features show limited accuracy for outcome prediction. The aim was to evaluate the prognostic value of whole blood transcriptome at an early stage of the disease. Blood transcriptome of patients with mild pneumonia was profiled. Patients with subsequent severe COVID-19 were compared to those with favourable outcome, and a molecular predictor based on gene expression was built. Unsupervised classification discriminated patients who would later develop a COVID-19-related severe pneumonia. The corresponding gene expression signature reflected the immune response to the viral infection dominated by a prominent type I interferon, with IFI27 among the most over-expressed genes. A 48-genes transcriptome signature predicting the risk of severe COVID-19 was built on a training cohort, then validated on an external independent cohort, showing an accuracy of 81% for predicting severe outcome. These results identify an early transcriptome signature of severe COVID-19 pneumonia, with a possible relevance to improve COVID-19 patient management.

Diaphragm reconstruction using a TachoSil patch as alternative to intrasellar packing for small focal diaphragm defects in pituitary surgery: a cohort study.

BACKGROUND: During pituitary surgery, CSF leaks are often treated by intrasellar packing, using muscle or fat grafts. However, this strategy may interfere with the interpretation of postoperative MRI and may impact the quality of resection in cases of second surgery, due to the existence of additional fibrous tissue. We present an alternative technique, using a diaphragm reconstruction with a heterologous sponge combining fibrinogen and thrombin (TachoSil), applied in selected patients with low-flow CSF leaks. This study investigates the surgical outcome of patients treated with this strategy. METHODS: From a cohort of 2231 patients treated from June 2011 to June 2023 by endoscopic endonasal approach for pituitary surgery, the surgical technique of diaphragm repair with TachoSil patch performed in 55 patients (2.6%) was detailed, and the rate of closure failure was analyzed at 6 months postoperatively. No intrasellar packing was used and sellar floor reconstruction was performed whenever possible. The rate of postoperative CSF leak was compared with that reported in three previous publications that also used the TachoSil patch technique. RESULTS: Patients were mostly women (F/M ratio: 1.2) with a median age of 53.6 years. Surgery was indicated for non-functioning adenomas, Cushing's disease, acromegaly, and Rathke's cleft cysts in 38/55 (69.1%), 6/55 (10.9%), 5/55 (9.1%) and 6/55 (10.9%) patients respectively. The rate of postoperative CSF leak was 1.8% (n = 1/55), which was not significantly different from that reported in the three cohorts from the literature (2.8%, p > 0.05). No postoperative meningitis was recorded. CONCLUSIONS: In highly selected patients with low-flow CSF leaks related to small focal diaphragm defects, diaphragm reconstruction using a TachoSil patch can be a safe and valuable alternative to intrasellar packing.

Pituitary surgery outcome in patients 75 years and older: a retrospective study.

BACKGROUND: As the population ages, the number of elderly patients with an indication for pituitary surgery is rising. Information on the outcome of patients aged over 75 is limited. This study reports a large series assessing the feasibility of surgical resection in this specific age range, focusing on surgical complications and postoperative results. METHODS: A retrospective cohort study of patients with pituitary adenomas and Rathke's cleft cysts was conducted. All patients were aged 75 years or over and treated by a single expert neurosurgical team. A control population included 2379 younger adult patients operated by the same surgeons during the same period. RESULTS: Between 2008 and 2022, 155 patients underwent surgery. Indication was based on vision impairment in most patients (79%). Median follow-up was 13 months (range: 3-96). The first surgery was performed with an endoscopic transsellar approach, an extended endonasal transtuberculum approach and a microscopic transcranial approach in 96%, 3%, and 1% of patients, respectively. Single surgery was sufficient to obtain volume control in 97% of patients. From Kaplan-Meier estimates, 2-year and 5-year disease control with a single surgery were 97.3% and 86.2%, respectively. Resection higher than 80% was achieved in 77% of patients. No vision worsening occurred. In acromegaly and Cushing's disease, endocrine remission was obtained in 90% of non-invasive adenomas. Surgical complications were noted in 5% of patients, with 30-day mortality, hematoma, cerebrospinal fluid leak, meningitis, and epistaxis occurring in 0.6%, 0.6%, 1.9%, 0.6%, and 1.3% respectively. New endocrine anterior deficits occurred in only 5%, while no persistent diabetes insipidus was noted. Compared with younger patients, the complication rate was not statistically different. CONCLUSIONS: Surgery beyond the age of 75, mainly relying on an endoscopic endonasal transsellar approach, is effective and safe, provided that patients are managed in tertiary centers.

KDM1A inactivation causes hereditary food-dependent Cushing syndrome.

PURPOSE: This study aimed to investigate the genetic cause of food-dependent Cushing syndrome (FDCS) observed in patients with primary bilateral macronodular adrenal hyperplasia (PBMAH) and adrenal ectopic expression of the glucose-dependent insulinotropic polypeptide receptor. Germline ARMC5 alterations have been reported in about 25% of PBMAH index cases but are absent in patients with FDCS. METHODS: A multiomics analysis of PBMAH tissues from 36 patients treated by adrenalectomy was performed (RNA sequencing, single-nucleotide variant array, methylome, miRNome, exome sequencing). RESULTS: The integrative analysis revealed 3 molecular groups with different clinical features, namely G1, comprising 16 patients with ARMC5 inactivating variants; G2, comprising 6 patients with FDCS with glucose-dependent insulinotropic polypeptide receptor ectopic expression; and G3, comprising 14 patients with a less severe phenotype. Exome sequencing revealed germline truncating variants of KDM1A in 5 G2 patients, constantly associated with a somatic loss of the KDM1A wild-type allele on 1p, leading to a loss of KDM1A expression both at messenger RNA and protein levels (P = 1.2 × 10-12 and P < .01, respectively). Subsequently, KDM1A pathogenic variants were identified in 4 of 4 additional index cases with FDCS. CONCLUSION: KDM1A inactivation explains about 90% of FDCS PBMAH. Genetic screening for ARMC5 and KDM1A can now be offered for most PBMAH operated patients and their families, opening the way to earlier diagnosis and improved management.

Cushing's disease: role of bilateral adrenalectomy.

INTRODUCTION: Laparoscopic bilateral adrenalectomy (BAD) is one of the treatments of Cushing's Disease (CD), but its indications and outcome is debated. METHODS: The literature on BAD was reviewed as part of a work performed for the Cushing's disease guideline. RESULTS: The surgical morbidity of BAD is reported between 10 and 18% and no mortality has been reported in the largest series. Because of the endocrine sacrifice it will be mostly performed after a multidisciplinary team discussion in selected cases of refractory CD (mostly after failure of pituitary surgery and/or medical treatment). It is also frequently discussed in female patients desiring pregnancy. Corticotroph tumor progression occurs in 40% of the patients but is in most patients manageable when detected early by a careful long term monitoring with pituitary MRI and ACTH assays after BAD. CONCLUSION: BAD is a safe and effective treatment of CD used in specific situations and requiring long term monitoring.

Long-term efficacy and safety of osilodrostat in Cushing's disease: final results from a Phase II study with an optional extension phase (LINC 2).

BACKGROUND: Many patients with Cushing's disease (CD) require long-term medical therapy to control their hypercortisolism. In the core phase of a Phase II study (LINC 2; NCT01331239), osilodrostat normalized mean urinary free cortisol (mUFC) in 78.9% of patients with CD. Here, we report long-term efficacy and safety data for osilodrostat following completion of an optional extension to LINC 2. METHODS: Adult patients with CD were enrolled in a 22-week prospective Phase II study. Patients with mUFC ≤ upper limit of normal (ULN) or receiving clinical benefit at week 22 could enter the optional extension. The proportion of complete (mUFC ≤ ULN) or partial (mUFC > ULN but ≥ 50% decrease from baseline) mUFC responders was assessed over time. RESULTS: Sixteen of 19 enrolled patients entered the extension. Median (range) osilodrostat exposure from baseline to study end was 5.4 years (0.04-6.7); median (range) average dose was 10.6 mg/day (1.1-47.9). Overall response rate (complete and partial mUFC responders) was consistently ≥ 50%. Sustained control of most cardiovascular-related parameters was observed during the extension. The long-term safety profile was consistent with that reported during the core phase. Testosterone levels (females) decreased towards baseline levels during long-term follow-up, with no new or worsening cases of hirsutism during the extension. CONCLUSIONS: In the longest prospective study of a steroidogenesis inhibitor to date, osilodrostat provided sustained reductions in mUFC for up to 6.7 years of treatment, with no new safety signals emerging during the extension. These findings support osilodrostat as an effective long-term treatment for patients with CD.

HOX genes promote cell proliferation and are potential therapeutic targets in adrenocortical tumours.

BACKGROUND: Understanding the pathways that drive adrenocortical carcinoma (ACC) is essential to the development of more effective therapies. This study investigates the role of the transcription factor HOXB9 and other HOX factors in ACC and its treatment. METHODS: We used transgenic mouse models to determine the role of Hoxb9 in adrenal tumour development. Patient transcriptomic data was analysed for the expression of HOX genes and their association with disease. Drug response studies on various adrenocortical models were done to establish novel therapeutic options. RESULTS: Our human ACC dataset analyses showed high expression of HOXB9, and other HOX factors, are associated with poorer prognosis. Transgenic overexpression of Hoxb9 in the adrenal cortex of mice with activated Ctnnb1 led to larger adrenal tumours. This phenotype was preferentially observed in male mice and was characterised by more proliferating cells and an increase in the expression of cell cycle genes, including Ccne1. Adrenal tumour cells were found to be dependent on HOX function for survival and were sensitive to a specific peptide inhibitor. CONCLUSIONS: These studies show Hoxb9 can promote adrenal tumour progression in a sex-dependent manner and have identified HOX factors as potential drug targets, leading to novel therapeutic approaches in ACC.

Surgical management of insulinoma over three decades.

BACKGROUND: This paper reports our experience of the perioperative management of patients with sporadic, non-malignant, pancreatic insulinoma. METHODS: A retrospective monocentric cohort study was performed from January 1989 to July 2019, including all the patients who had been operated on for pancreatic insulinoma. The preoperative work-up, surgical management, and postoperative outcome were analyzed. RESULTS: Eighty patients underwent surgery for sporadic pancreatic insulinoma, 50 of which were female (62%), with a median age of 50 (36-70) years. Preoperatively, the tumors were localized in 76 patients (95%). Computed tomography (CT) and magnetic resonance imaging allowed exact preoperative tumor localization in 76% of the patients (64-85 and 58-88 patients, respectively), increasing to 96% when endoscopic ultrasonography was performed. Forty-one parenchyma-sparing pancreatectomies (PSP) (including enucleation, caudal pancreatectomy, and uncinate process resection) and 39 pancreatic resections were performed. The mortality rate was 6% (n = 5), with a morbidity rate of 72%, including 24 severe complications (30%) and 35 pancreatic fistulas (44%). No differences were found between formal pancreatectomy and PSP in terms of postoperative outcome procedures. The surgery was curative in all the patients. CONCLUSION: CT used in combination with endoscopic ultrasonography allows accurate localization of insulinomas in almost all patients. When possible, a parenchyma-sparing pancreatectomy should be proposed as the first-line surgical strategy.

Hormonal and spatial control of SUMOylation in the human and mouse adrenal cortex.

SUMOylation is a highly conserved and dynamic post-translational mechanism primarily affecting nuclear programs for adapting organisms to stressful challenges. Alteration of SUMOylation cycles leads to severe developmental and homeostatic defects and malignancy, but signals coordinating SUMOylation are still unidentified. The adrenal cortex is a zonated endocrine gland that controls body homeostasis and stress response. Here, we show that in human and in mouse adrenals, SUMOylation follows a decreasing centripetal gradient that mirrors cortical differentiation flow and delimits highly and weakly SUMOylated steroidogenic compartments, overlapping glomerulosa, and fasciculata zones. Activation of PKA signaling by acute hormonal treatment, mouse genetic engineering, or in Carney complex results in repression of small ubiquitin-like modifier (SUMO) conjugation in the inner cortex by coordinating expression of SUMO pathway inducers and repressors. Conversely, genetic activation of canonical wingless-related integration site signaling maintains high SUMOylation potential in the outer neoplastic cortex. Thus, SUMOylation is tightly regulated by signaling pathways that orchestrate adrenal zonation and diseases.-Dumontet, T., Sahut-Barnola, I., Dufour, D., Lefrançois-Martinez, A.-M., Berthon, A., Montanier, N., Ragazzon, B., Djari, C., Pointud, J.-C., Roucher-Boulez, F., Batisse-Lignier, M., Tauveron, I., Bertherat, J., Val, P., Martinez, A. Hormonal and spatial control of SUMOylation in the human and mouse adrenal cortex.

Update of Genetic and Molecular Causes of Adrenocortical Hyperplasias Causing Cushing Syndrome.

Bilateral hyperplasias of the adrenal cortex are rare causes of chronic endogenous hypercortisolemia also called Cushing syndrome. These hyperplasias have been classified in two categories based on the adrenal nodule size: the micronodular types include Primary Pigmented Nodular Adrenocortical Disease (PPNAD) and isolated Micronodular Adrenal Disease (iMAD) and the macronodular also named Primary Bilateral Macronodular Adrenal Hyperplasia (PBMAH). This review discusses the genetic and molecular causes of these different forms of hyperplasia that involve mutations and dysregulation of various regulators of the cAMP/protein kinase A (PKA) pathway. PKA signaling is the main pathway controlling cortisol secretion in adrenocortical cells under ACTH stimulation. Although mutations of the regulatory subunit R1α of PKA (PRKAR1A) is the main cause of familial and sporadic PPNAD, inactivation of two cAMP-binding phosphodiesterases (PDE11A and PDE8B) are associated with iMAD even if they are also found in PPNAD and PBMAH cases. Interestingly, PBMAH that is observed in multiple familial syndrome such as APC, menin, fumarate hydratase genes, has initially been associated with the aberrant expression of G-protein coupled receptors (GPCR) leading to an activation of cAMP/PKA pathway. However, more recently, the discovery of germline mutations in Armadillo repeat containing protein 5 (ARMC5) gene in 25-50% of PBMAH patients highlights its importance in the development of PBMAH. The potential relationship between ARMC5 mutations and aberrant GPCR expression is discussed as well as the potential other causes of PBMAH.

18F-fluorocholine PET/CT in MEN1 Patients with Primary Hyperparathyroidism.

BACKGROUND: Primary hyperparathyroidism (HPT1) is the most frequent endocrinopathy in multiple endocrine neoplasia type 1 (MEN1). Its surgical management is challenging. We aimed to describe and compare the imaging findings of parathyroid ultrasound (US), sestaMIBI scintigraphy (sestaMIBI), and 18F-fluorocholine (FCH) PET/CT in a series of MEN1 patients with HPT1. METHODS: Retrospective analysis of a cohort of MEN1 patients with HPT1 assessed by parathyroid US, sestaMIBI scintigraphy and SPECT/CT, and FCH-PET/CT for potential surgery between 2015 and 2019. RESULTS: Twenty-two patients with a confirmed diagnosis of MEN1 who presented with HPT1 and were assessed by the 3 imaging modalities were included. After imaging workups, 11 patients were operated on for the first time, 4 underwent a redo surgery, and 7 did not undergo an operation. The overall patient-based positivity rate of imaging was 91% (20 of 22) for parathyroid US and 96% (21 of 22) for both sestaMIBI and FCH-PET/CT. The 3 imaging modalities demonstrated negative findings in 1/22 patient who did not undergo surgery. Overall, 3 pathologic glands were not detected by any imaging technique. SestaMIBI and FCH-PET/CT both resulted in the same 3 false-positive results in ectopic areas with a significant uptake on two thymic carcinoid tumors and one inflammatory lymph node. FCH-PET/CT provided more surgically relevant data than sestaMIBI in 4/11 patients with initial surgery and in 1/4 patient who underwent redo surgery. CONCLUSIONS: Compared to sestaMIBI scintigraphy, FCH-PET/CT provides additional information regarding the number of pathologic parathyroid glands and their localization in MEN1 patients with HPT1.

Targeted next-generation sequencing detects rare genetic events in pheochromocytoma and paraganglioma.

BACKGROUND: Knowing the genetic status of patients affected by paragangliomas and pheochromocytomas (PPGL) is important for the guidance of their management and their relatives. Our objective was to improve the diagnostic performances of PPGL genetic testing by next-generation sequencing (NGS). METHODS: We developed a custom multigene panel, which includes 17 PPGL genes and is compatible with both germline and tumour DNA screening. The NGS assay was first validated in a retrospective cohort of 201 frozen tumour DNAs and then applied prospectively to 623 DNAs extracted from leucocytes, frozen or paraffin-embedded PPGL tumours. RESULTS: In the retrospective cohort, the sensitivity of the NGS assay was evaluated at 100% for point and indels mutations and 86% for large rearrangements. The mutation rate was re-evaluated from 65% (132/202) to 78% (156/201) after NGS analysis. In the prospective cohort, NGS detected not only germline and somatic mutations but also co-occurring variants and mosaicism. A mutation was identified in 74% of patients for whom both germline and tumour DNA were available. CONCLUSION: The analysis of 824 DNAs from patients with PPGL demonstrated that NGS assay significantly improves the performances of PPGL genetic testing compared with conventional methods, increasing the rate of identified mutations and identifying rare genetic mechanisms.

EZH2 cooperates with E2F1 to stimulate expression of genes involved in adrenocortical carcinoma aggressiveness.

BACKGROUND: EZH2 is overexpressed and associated with poor prognosis in adrenocortical carcinoma (ACC) and its inhibition reduces growth and aggressiveness of ACC cells in culture. Although EZH2 was identified as the methyltransferase that deposits the repressive H3K27me3 histone mark, it can cooperate with transcription factors to stimulate gene transcription. METHODS: We used bioinformatics approaches on gene expression data from three cohorts of patients and a mouse model of EZH2 ablation, to identify targets and mode of action of EZH2 in ACC. This was followed by ChIP and functional assays to evaluate contribution of identified targets to ACC pathogenesis. RESULTS: We show that EZH2 mostly works as a transcriptional inducer in ACC, through cooperation with the transcription factor E2F1 and identify three positive targets involved in cell cycle regulation and mitosis i.e., RRM2, PTTG1 and ASE1/PRC1. Overexpression of these genes is associated with poor prognosis, suggesting a potential role in acquisition of aggressive ACC features. Pharmacological and siRNA-mediated inhibition of RRM2 blocks cell proliferation, induces apoptosis and inhibits cell migration, suggesting that it may be an interesting target in ACC. CONCLUSIONS: Altogether, these data show an unexpected role of EZH2 and E2F1 in stimulating expression of genes associated with ACC aggressiveness.

MiR-483-5p and miR-139-5p promote aggressiveness by targeting N-myc downstream-regulated gene family members in adrenocortical cancer.

Adrenocortical carcinoma (ACC) is a tumor with poor prognosis in which overexpression of a panel of microRNAs has been associated with malignancy but a very limited number of investigations on their role in ACC pathogenesis have been conducted. We examined the involvement of miR-483-5p and miR-139-5p in adrenocortical cancer aggressiveness. Using bioinformatics predictions and mRNA/miRNA expression profiles, we performed an integrated analysis to identify inversely correlated miRNA-mRNA pairs in ACC. We identified N-myc downstream-regulated gene family members 2 and 4 (NDRG2 and NDRG4) as targets of miR-483-5p and miR-139-5p, respectively. NDRG2 and NDRG4 expressions were inversely correlated respectively with miR-483-5p and miR-139-5p levels in aggressive ACC samples from two independent cohorts of 20 and 44 ACC. Moreover, upregulation of miR-139-5p and downregulation of NDRG4 demonstrated a striking prognostic value. A direct interaction between miR-483-5p or miR-139-5p and their targets was demonstrated in reporter assays. Downregulation of miR-483-5p or miR-139-5p in the ACC cell lines NCI-H295R and SW13 increased NDRG2 or NDRG4 mRNA and protein expression, compromised adrenocortical cancer cell invasiveness and anchorage-independent growth. MiR-483-5p or miR-139-5p overexpression and NDRG2 or NDRG4 inhibition produce similar changes, which are rescued by NDRG2 or NDRG4 ectopic expression. We established that key factors mediating epithelial-to-mesenchymal transition are downstream effectors of miR-483-5p/NDRG2 and miR-139-5p/NDRG4 pathways. Collectively, our data show for the first time that miR-483-5p/NDRG2 and miR-139-5p/NDRG4 axes promote ACC aggressiveness, with potential implications for prognosis and therapeutic interventions in adrenocortical malignancies.

EZH2 is overexpressed in adrenocortical carcinoma and is associated with disease progression.

Adrenal Cortex Carcinoma (ACC) is an aggressive tumour with poor prognosis. Common alterations in patients include constitutive WNT/ß-catenin signalling and overexpression of the growth factor IGF2. However, the combination of both alterations in transgenic mice is not sufficient to trigger malignant tumour progression, suggesting that other alterations are required to allow development of carcinomas. Here, we have conducted a study of publicly available gene expression data from three cohorts of ACC patients to identify relevant alterations. Our data show that the histone methyltransferase EZH2 is overexpressed in ACC in the three cohorts. This overexpression is the result of deregulated P53/RB/E2F pathway activity and is associated with increased proliferation and poorer prognosis in patients. Inhibition of EZH2 by RNA interference or pharmacological treatment with DZNep inhibits cellular growth, wound healing and clonogenic growth and induces apoptosis of H295R cells in culture. Further growth inhibition is obtained when DZNep is combined with mitotane, the gold-standard treatment for ACC. Altogether, these observations suggest that overexpression of EZH2 is associated with aggressive progression and may constitute an interesting therapeutic target in the context of ACC.

Clinicopathological description of 43 oncocytic adrenocortical tumors: importance of Ki-67 in histoprognostic evaluation.

Oncocytic adrenocortical tumors are a rare subtype of adrenal tumors with challenging diagnosis and histoprognostic assessment. It is usually believed that oncocytic adrenocortical tumors have a more indolent clinical behavior than conventional adrenocortical tumors. As the Weiss score overestimates the malignancy of oncocytic adrenocortical tumors owing to intrinsic parameters, alternative scores have been proposed. The Lin-Weiss-Bisceglia score is currently recommended. We performed a large nationwide multicenter retrospective clinicopathologic study of oncocytic adrenocortical tumors. Among the 43 patients in our cohort, 40 patients were alive without disease, 2 patients died of their disease and 1 patient was alive with relapse after a median follow-up of 38 months (20-59). Our data revealed that over 50% of the oncocytic adrenocortical tumor cases were diagnosed as carcinoma whatever the classification systems used, including the Lin-Weiss-Bisceglia score. The exception is the Helsinki score, which incorporates the Ki-67 proliferation index and was the most specific prognostic score for oncocytic adrenocortical tumor malignancy without showing a loss in sensitivity. A comparison of malignant oncocytic adrenocortical tumors with conventional adrenocortical carcinomas matched for age, sex, ENS@T stage and surgical resection status showed significant better overall survival of malignant oncocytic adrenocortical tumors.

Mutational signature analysis identifies MUTYH deficiency in colorectal cancers and adrenocortical carcinomas.

Germline alterations in DNA repair genes are implicated in cancer predisposition and can result in characteristic mutational signatures. However, specific mutational signatures associated with base excision repair (BER) defects remain to be characterized. Here, by analysing a series of colorectal cancers (CRCs) using exome sequencing, we identified a particular spectrum of somatic mutations characterized by an enrichment of C > A transversions in NpCpA or NpCpT contexts in three tumours from a MUTYH-associated polyposis (MAP) patient and in two cases harbouring pathogenic germline MUTYH mutations. In two series of adrenocortical carcinomas (ACCs), we identified four tumours with a similar signature also presenting germline MUTYH mutations. Taken together, these findings demonstrate that MUTYH inactivation results in a particular mutational signature, which may serve as a useful marker of BER-related genomic instability in new cancer types. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Risk assessment of maternally inherited SDHD paraganglioma and phaeochromocytoma.

BACKGROUND: Germline mutations in the SDHD tumour suppressor gene (11q23.1) predispose to phaeochromocytomas and paragangliomas (PPGL) mainly on a paternal transmission. However, PPGL have been recently reported in three carriers of a maternally inherited SDHD mutation. OBJECTIVE: To assess the risk of PPGL occurrence on maternal transmission of SDHD mutation. METHODS: Pedigrees of 80 SDHD-related families have been reviewed. 35 asymptomatic subjects carrying a maternally transmitted SDHD mutation were identified. 20 of them accepted to benefit from a PPGL imaging screening. RESULTS: A unique histologically proven biochemically negative phaeochromocytoma has been diagnosed in a 35-year-old woman. Molecular investigations carried out on tumour tissue revealed that the loss of heterozygosity encompassed the paternally derived q arm and the maternally derived p arm of chromosome 11. CONCLUSIONS: This study demonstrates that the risk of developing PPGL for a subject carrying a germline SDHD mutation on the maternal allele remains a rare scenario but does exist. Our data suggest an adjustment of current genetic counselling and clinical care recommendations for at-risk subjects. A targeted familial genetic test should be proposed from the age of 18 years to every subject having a mother carrying a germline SDHD mutation and a first medical workup, including imaging, should be recommended to SDHD-positive mutation carriers.

Constitutive activation of PKA catalytic subunit in adrenal Cushing's syndrome.

BACKGROUND: Corticotropin-independent Cushing's syndrome is caused by tumors or hyperplasia of the adrenal cortex. The molecular pathogenesis of cortisol-producing adrenal adenomas is not well understood. METHODS: We performed exome sequencing of tumor-tissue specimens from 10 patients with cortisol-producing adrenal adenomas and evaluated recurrent mutations in candidate genes in an additional 171 patients with adrenocortical tumors. We also performed genomewide copy-number analysis in 35 patients with cortisol-secreting bilateral adrenal hyperplasias. We studied the effects of these genetic defects both clinically and in vitro. RESULTS: Exome sequencing revealed somatic mutations in PRKACA, which encodes the catalytic subunit of cyclic AMP-dependent protein kinase (protein kinase A [PKA]), in 8 of 10 adenomas (c.617A→C in 7 and c.595_596insCAC in 1). Overall, PRKACA somatic mutations were identified in 22 of 59 unilateral adenomas (37%) from patients with overt Cushing's syndrome; these mutations were not detectable in 40 patients with subclinical hypercortisolism or in 82 patients with other adrenal tumors. Among 35 patients with cortisol-producing hyperplasias, 5 (including 2 first-degree relatives) carried a germline copy-number gain (duplication) of the genomic region on chromosome 19 that includes PRKACA. In vitro studies showed impaired inhibition of both PKA catalytic subunit mutants by the PKA regulatory subunit, whereas cells from patients with germline chromosomal gains showed increased protein levels of the PKA catalytic subunit; in both instances, basal PKA activity was increased. CONCLUSIONS: Genetic alterations of the catalytic subunit of PKA were found to be associated with human disease. Germline duplications of this gene resulted in bilateral adrenal hyperplasias, whereas somatic PRKACA mutations resulted in unilateral cortisol-producing adrenal adenomas. (Funded by the European Commission Seventh Framework Program and others.).

Gigantism and acromegaly due to Xq26 microduplications and GPR101 mutation.

BACKGROUND: Increased secretion of growth hormone leads to gigantism in children and acromegaly in adults; the genetic causes of gigantism and acromegaly are poorly understood. METHODS: We performed clinical and genetic studies of samples obtained from 43 patients with gigantism and then sequenced an implicated gene in samples from 248 patients with acromegaly. RESULTS: We observed microduplication on chromosome Xq26.3 in samples from 13 patients with gigantism; of these samples, 4 were obtained from members of two unrelated kindreds, and 9 were from patients with sporadic cases. All the patients had disease onset during early childhood. Of the patients with gigantism who did not carry an Xq26.3 microduplication, none presented before the age of 5 years. Genomic characterization of the Xq26.3 region suggests that the microduplications are generated during chromosome replication and that they contain four protein-coding genes. Only one of these genes, GPR101, which encodes a G-protein-coupled receptor, was overexpressed in patients' pituitary lesions. We identified a recurrent GPR101 mutation (p.E308D) in 11 of 248 patients with acromegaly, with the mutation found mostly in tumors. When the mutation was transfected into rat GH3 cells, it led to increased release of growth hormone and proliferation of growth hormone-producing cells. CONCLUSIONS: We describe a pediatric disorder (which we have termed X-linked acrogigantism [X-LAG]) that is caused by an Xq26.3 genomic duplication and is characterized by early-onset gigantism resulting from an excess of growth hormone. Duplication of GPR101 probably causes X-LAG. We also found a recurrent mutation in GPR101 in some adults with acromegaly. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others.).