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Supplementary Table 3 from Transcriptome Analysis Reveals that p53 and β-Catenin Alterations Occur in a Group of Aggressive Adrenocortical Cancers

Supplementary Table 2 from Transcriptome Analysis Reveals that p53 and β-Catenin Alterations Occur in a Group of Aggressive Adrenocortical Cancers

Supplementary Table 1 from Transcriptome Analysis Reveals that p53 and β-Catenin Alterations Occur in a Group of Aggressive Adrenocortical Cancers

ARMC5 (Armadillo repeat containing 5 gene) was identified as a new tumor suppressor gene responsible for hereditary adrenocortical tumors and meningiomas. ARMC5 is ubiquitously expressed and encodes a protein which contains a N-terminal Armadillo repeat domain and a C-terminal BTB (Bric-a-Brac, Tramtrack and Broad-complex) domain, both docking platforms for numerous proteins. At present, expression regulation and mechanisms of action of ARMC5 are almost unknown. In this study, we showed that ARMC5 interacts with CUL3 requiring its BTB domain. This interaction leads to ARMC5 ubiquitination and further degradation by the proteasome. ARMC5 alters cell cycle (G1/S phases and cyclin E accumulation) and this effect is blocked by CUL3. Moreover, missense mutants in the BTB domain of ARMC5, identified in patients with multiple adrenocortical tumors, are neither able to interact and be degraded by CUL3/proteasome nor alter cell cycle. These data show a new mechanism of regulation of the ARMC5 protein and open new perspectives in the understanding of its tumor suppressor activity.

Background Mutations in four genes, WNK lysine deficient protein kinase 1 and 4 ( WNK1 and WNK4 ), kelch like family member 3 ( KLHL3 ), or Cullin 3 ( CUL3 ), can result in familial hyperkalemic hypertension (FHHt), a rare Mendelian form of human arterial hypertension. Although all mutations result in an increased abundance of WNK1 or WNK4, all FHHt-causing CUL3 mutations, resulting in the skipping of exon 9, lead to a more severe phenotype. Methods We created and compared two mouse models, one expressing the mutant Cul3 protein ubiquitously ( pgk-Cul3∆9 ) and the other specifically in vascular smooth muscle cells ( SM22-Cul3∆9 ). We conducted pharmacologic investigations on isolated aortas and generated stable and inducible HEK293 cell lines that overexpress the wild-type Cul3 or mutant Cul3 (Cul3 ∆ 9) protein. Results As expected, pgk-Cul3∆9 mice showed marked hypertension with significant hyperkalemia, hyperchloremia and low renin. BP increased significantly in SM22-Cul3∆9 mice, independent of any measurable effect on renal transport. Only pgk-Cul3∆9 mice displayed increased expression of the sodium chloride cotransporter and phosphorylation by the WNK-SPAK kinases. Both models showed altered reactivity of isolated aortas to phenylephrine and acetylcholine, as well as marked acute BP sensitivity to the calcium channel blocker amlodipine. Aortas from SM22-Cul3∆9 mice showed increased expression of RhoA, a key molecule involved in regulation of vascular tone, compared with aortas from control mice. We also observed increased RhoA abundance and t 1/2 in Cul3 ∆ 9-expressing cells, caused by decreased ubiquitination. Conclusions Mutations in Cul3 cause severe hypertension by affecting both renal and vascular function, the latter being associated with activation of RhoA.

International audience; The triggering receptor expressed on myeloid cells 1 (TREM-1) drives inflammatory responses in several cardiovascular diseases but its role in abdominal aortic aneurysm (AAA) remains unknown. Our objective was to explore the role of TREM-1 in a mouse model of angiotensin II-induced (AngII-induced) AAA. TREM-1 expression was detected in mouse aortic aneurysm and colocalized with macrophages. Trem1 gene deletion (Apoe-/-Trem1-/-), as well as TREM-1 pharmacological blockade with LR-12 peptide, limited both AAA development and severity. Trem1 gene deletion attenuated the inflammatory response in the aorta, with a reduction of Il1b, Tnfa, Mmp2, and Mmp9 mRNA expression, and led to a decreased macrophage content due to a reduction of Ly6Chi classical monocyte trafficking. Conversely, antibody-mediated TREM-1 stimulation exacerbated Ly6Chi monocyte aorta infiltration after AngII infusion through CD62L upregulation and promoted proinflammatory signature in the aorta, resulting in worsening AAA severity. AngII infusion stimulated TREM-1 expression and activation on Ly6Chi monocytes through AngII receptor type I (AT1R). In human AAA, TREM-1 was detected and TREM1 mRNA expression correlated with SELL mRNA expression. Finally, circulating levels of sTREM-1 were increased in patients with AAA when compared with patients without AAA. In conclusion, TREM-1 is involved in AAA pathophysiology and may represent a promising therapeutic target in humans.

Cullin 3 (CUL3) is the scaffold of Cullin3 Ring E3-ligases (CRL3s), which use various BTB-adaptor proteins to ubiquitinate numerous substrates targeting their proteasomal degradation. CUL3 mutations, responsible for a severe form of familial hyperkalemia and hypertension (FHHt), all result in a deletion of exon 9 (amino-acids 403-459) (CUL3-∆9). Surprisingly, while CUL3-∆9 is hyperneddylated, a post-translational modification that typically activates CRL complexes, it is unable to ubiquitinate its substrates. In order to understand the mechanisms behind this loss-of function, we performed comparative label-free quantitative analyses of CUL3 and CUL3-∆9 interactome by mass spectrometry. It was observed that CUL3-∆9 interactions with COP9 and CAND1, both involved in CRL3 complexes’ dynamic assembly, were disrupted. These defects result in a reduction in the dynamic cycling of the CRL3 complexes, making the CRL3-∆9 complex an inactive BTB-adaptor trap, as demonstrated by SILAC experiments. Collectively, the data indicated that the hyperneddylated CUL3-∆9 protein is inactive as a consequence of several structural changes disrupting its dynamic interactions with key regulatory partners.

In humans, activating mutations in the PRKAR1A gene cause acrodysostosis 1 (ACRDYS1). These mutations result in a reduction in PKA activation caused by an impaired ability of cAMP to dissociate mutant PRKAR1A from catalytic PKA subunits. Two striking features of this rare developmental disease are renal resistance to PTH and chondrodysplasia resulting from the constitutive inhibition of PTHR1/Gsa/AC/cAMP/PKA signaling. We developed a knock-in of the recurrent ACRDYS1 R368X PRKAR1A mutation in the mouse. No litters were obtained from [R368X]/[+] females (thus no homozygous [R368X]/[R368X] mice). In [R368X]/[+] mice, Western blot analysis confirmed mutant allele heterozygous expression. Growth retardation, peripheral acrodysostosis (including brachydactyly affecting all digits), and facial dysostosis were shown in [R368X]/[+] mice by weight curves and skeletal measurements (μCT scan) as a function of time. [R368X]/[+] male and female mice were similarly affected. Unexpected, however, whole-mount skeletal preparations revealed a striking delay in mineralization in newborn mutant mice, accompanied by a decrease in the height of terminal hypertrophic chondrocyte layer, an increase in the height of columnar proliferative prehypertrophic chondrocyte layer, and changes in the number and spatial arrangement of proliferating cell nuclear antigen (PCNA)-positive chondrocytes. Plasma PTH and basal urinary cAMP were significantly higher in [R368X]/[+] compared to WT mice. PTH injection increased urinary cAMP similarly in [R368X]/[+] and WT mice. PRKACA expression was regulated in a tissue (kidney not bone and liver) manner. This model, the first describing the germline expression of a PRKAR1A mutation causing dominant repression of cAMP-dependent PKA, reproduced the main features of ACRDYS1 in humans. It should help decipher the specificity of the cAMP/PKA signaling pathway, crucial for numerous stimuli. In addition, our results indicate that PRKAR1A, by tempering intracellular cAMP levels, is a molecular switch at the crossroads of signaling pathways regulating chondrocyte proliferation and differentiation. © 2016 American Society for Bone and Mineral Research.

International audience; Gain-of-function mutations in with no lysine (K) 1 (WNK1) and WNK4 genes are responsible for familial hyperkalemic hypertension (FHHt), a rare, inherited disorder characterized by arterial hypertension and hyperkalemia with metabolic acidosis. More recently, FHHt-causing mutations in the Kelch-like 3-Cullin 3 (KLHL3-CUL3) E3 ubiquitin ligase complex have shed light on the importance of WNK's cellular degradation on renal ion transport. Using full exome sequencing for a 4-generation family and then targeted sequencing in other suspected cases, we have identified new missense variants in the WNK1 gene clustering in the short conserved acidic motif known to interact with the KLHL3-CUL3 ubiquitin complex. Affected subjects had an early onset of a hyperkalemic hyperchloremic phenotype, but normal blood pressure values"Functional experiments in Xenopus laevis oocytes and HEK293T cells demonstrated that these mutations strongly decrease the ubiquitination of the kidney-specific isoform KS-WNK1 by the KLHL3-CUL3 complex rather than the long ubiquitous catalytically active L-WNK1 isoform. A corresponding CRISPR/Cas9 engineered mouse model recapitulated both the clinical and biological phenotypes. Renal investigations showed increased activation of the Ste20 proline alanine-rich kinase-Na+-Cl- cotransporter (SPAK-NCC) phosphorylation cascade, associated with impaired ROMK apical expression in the distal part of the renal tubule. Together, these new WNK1 genetic variants highlight the importance of the KS-WNK1 isoform abundance on potassium homeostasis.

Background ARMC5 has been identified as the gene responsible for PBMAH (primary bilateral macronodular adrenal hyperplasia). ARMC5 inactivating mutations are reported in 20 to 25% of PBMAH patients. ARMC5 is considered as a tumor suppressor gene controlling apoptosis and regulating steroidogenesis. The mechanisms of action of ARMC5 are unknown. The structure of the ARMC5 protein contains ARM repeats and a BTB domain, patterns known to play a role in protein-protein interactions. Therefore identification of proteins that interact with ARMC5 and study of the mechanisms of this interaction will help to understand its function. By co-immunoprecipitation followed by mass spectrometry in HEK293 cells we identified a potential interaction between ARMC5 and Cullin3 (Cul3), also suggested in online databases and by 2 Hybrid Assay (Hu et al., 2017). Cul3 is a protein that mediates the ubiquitination process and subsequent degradation of specific protein substrates. Therefore, the aim of this study was to confirm this interaction and to investigate its mechanisms. Methods We used immunoprecipitation experiments with HA-tagged Cul3 and the bioluminescence resonance energy transfer (BRET) proximity assay in HEK293 cells in order to confirm and investigate the interaction of ARMC5 with Cul3. Results ARMC5 co-immunoprecipitated with HA-Cul3 and a hyperbolic BRET saturation curve was observed with YFP-Cul3 and ARMC5-Luc indicating a specific close proximity between these two proteins. We have also observed that a missense mutation in the BTB domain (p.L754P) of ARMC5 disrupts the interaction with Cul3. Altogether, these complementary approaches demonstrate that ARMC5 and Cul3 form a complex involving the BTB domain of ARMC5. Conclusion These data demonstrate that Cul3 is an ARMC5 partner. A likely direct interaction involves the BTB domain of ARMC5 and can be altered by pathogenic ARMC5 missense mutations. This suggests that ARMC5 participates in the ubiquitination process and open new perspectives in the pathophysiology of PBMAH.

The main target of cAMP is PKA, the main regulatory subunit of which (PRKAR1A) presents mutations in two genetic disorders: acrodysostosis and Carney complex. In addition to the initial recurrent mutation (R368X) of the PRKAR1A gene, several missense and nonsense mutations have been observed recently in acrodysostosis with hormonal resistance. These mutations are located in one of the two cAMP-binding domains of the protein, and their functional characterization is presented here. Expression of each of the PRKAR1A mutants results in a reduction of forskolin-induced PKA activation (measured by a reporter assay) and an impaired ability of cAMP to dissociate PRKAR1A from the catalytic PKA subunits by BRET assay. Modeling studies and sensitivity to cAMP analogs specific for domain A (8-piperidinoadenosine 3',5'-cyclic monophosphate) or domain B (8-(6-aminohexyl)aminoadenosine-3',5'-cyclic monophosphate) indicate that the mutations impair cAMP binding locally in the domain containing the mutation. Interestingly, two of these mutations affect amino acids for which alternative amino acid substitutions have been reported to cause the Carney complex phenotype. To decipher the molecular mechanism through which homologous substitutions can produce such strikingly different clinical phenotypes, we studied these mutations using the same approaches. Interestingly, the Carney mutants also demonstrated resistance to cAMP, but they expressed additional functional defects, including accelerated PRKAR1A protein degradation. These data demonstrate that a cAMP binding defect is the common molecular mechanism for resistance of PKA activation in acrodysosotosis and that several distinct mechanisms lead to constitutive PKA activation in Carney complex.

International audience; Context:Adrenocortical cancer (ACC) is an aggressive tumor with a heterogeneous outcome. Prognostic stratification is difficult even based on tumor stage and Ki67. Recently integrated genomics studies have demonstrated that CpG islands hypermethylation is correlated with poor survival.Objective:The goal of this study was to confirm the prognostic value of CpG islands methylation on an independent cohort.Design:Methylation was measured by methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA).Setting:MS-MLPA was performed in a training cohort of 50 patients with ACC to identify the best set of probes correlating with disease-free survival (DFS) and overall survival (OS). These outcomes were validated in an independent cohort from 21 ENSAT centers.Patients:The validation cohort included 203 patients (64% women, median age 50 years, 80% localized tumors).Main Outcome Measures:DFS and OS.Results:In the training cohort, mean methylation of 4 genes (PAX5, GSTP1, PYCARD, PAX6) was the strongest methylation marker. In the validation cohort, methylation was a significant prognostic factor of DFS (P < 0.0001) and OS (P < 0.0001). Methylation, Ki67, and ENSAT stage were combined in multivariate models. For DFS, methylation (P = 0.0005) and stage (P < 0.0001) but not Ki67 (P = 0.19) remained highly significant. For OS, methylation (P = 0.0006), stage (P < 0.0001), and Ki67 (P = 0.024) were independent prognostic factors.Conclusions:Tumor DNA methylation emerges as an independent prognostic factor in ACC. MS-MLPA is readily compatible with clinical routine and should enhance our ability for prognostication and precision medicine.

International audience; GIP-dependent Cushing's syndrome is caused by ectopic expression of glucose-dependent insulinotropic polypeptide receptor (GIPR) in cortisol-producing adrenal adenomas or in bilateral macronodular adrenal hyperplasias. Molecular mechanisms leading to ectopic GIPR expression in adrenal tissue are not known. Here we performed molecular analyses on adrenocortical adenomas and bilateral macronodular adrenal hyperplasias obtained from 14 patients with GIP-dependent adrenal Cushing's syndrome and one patient with GIP-dependent aldosteronism. GIPR expression in all adenoma and hyperplasia samples occurred through transcriptional activation of a single allele of the GIPR gene. While no abnormality was detected in proximal GIPR promoter methylation, we identified somatic duplications in chromosome region 19q13.32 containing the GIPR locus in the adrenocortical lesions derived from 3 patients. In 2 adenoma samples, the duplicated 19q13.32 region was rearranged with other chromosome regions, whereas a single tissue sample with hyperplasia had a 19q duplication only. We demonstrated that juxtaposition with cis-acting regulatory sequences such as glucocorticoid response elements in the newly identified genomic environment drives abnormal expression of the translocated GIPR allele in adenoma cells. Altogether, our results provide insight into the molecular pathogenesis of GIP-dependent Cushing's syndrome, occurring through monoallelic transcriptional activation of GIPR driven in some adrenal lesions by structural variations.

Context: Recurrent somatic mutations in KCNJ5, CACNA1D, ATP1A1, and ATP2B3 have been identified in aldosterone-producing adenomas (APAs). The question as to whether they are responsible for both nodulation and aldosterone production is not solved. Case Description: We describe the case of a young patient who was diagnosed with severe arterial hypertension due to primary aldosteronism at age 26 years, followed by hemorrhagic stroke 4 years later. Abdominal computed tomography showed bilateral macronodular adrenal hyperplasia. Identification of lateralized aldosterone secretion led to right adrenalectomy, followed by normalization of biochemical and hormonal parameters and amelioration of blood pressure. The resected adrenal showed three nodules, one of them expressing aldosterone synthase and harboring a somatic KNCJ5 mutation. A Weiss revisited index of 3 of the APA prompted us to perform a second 18F-2-fluoro-2-deoxy-D-glucose-positron emission tomography after surgery, which revealed abnormal rectal activity despite the absence of clinical symptoms. Gastrointestinal exploration showed multiple polyps with severe dysplasia, and the diagnosis of familial adenomatous polyposis was established in the presence of a germline heterozygous APC gene mutation. Sequencing of somatic DNA from the APA and a second adrenal nodule revealed biallelic APC inactivation due to loss of heterozygosity in both nodules. Conclusions: This case report underlines the need for establishing the frequency of germline APC variants in patients with primary aldosteronism and bilateral macronodular adrenal hyperplasia because their presence may predispose to APA development and severe hypertension well before the first familial adenomatous polyposis symptoms appear. From a mechanistic point of view, it supports a two-hit model for APA development, whereby the first hit drives increased cell proliferation whereas the second hit specifies the pattern of hormonal secretion.

Background Familial small-intestine neuroendocrine tumors (SI-NETs) are an exceptional inherited entity. Underlying predisposing mechanisms are unelucidated, but inositol polyphosphate multikinase ( IPMK ) gene alterations might promote their tumorigenesis. Methods A retrospective-prospective nationwide cohort was constituted, by including patients with proven SI-NETs and at least one relative with the same disease. We performed constitutional and somatic IPMK sequencing, and somatic DNA comparative genomic hybridization (CGH). Results We included 17 patients from 8 families, who were characterized by high prevalence (57%) of multiple SI-NETs, and high frequency of distant metastases (82%) and carcinoid syndrome (65%). No IPMK mutation was found in constitutional or tumor DNA. CGH array revealed recurrent chromosome-18 deletions but no alteration in the IPMK region. Conclusion We report here the first European series of patients with familial SI-NETs. Predisposing mechanisms may not involve the IPMK -encoding sequence or chromosomal region and might not differ from those of sporadic SI-NETs.

In humans, activating mutations in the PRKAR1A gene cause acrodysostosis 1 (ACRDYS1). These mutations result in a reduction in PKA activation caused by an impaired ability of cAMP to dissociate mutant PRKAR1A from catalytic PKA subunits. Two striking features of this rare developmental disease are renal resistance to PTH and chondrodysplasia resulting from the constitutive inhibition of PTHR1/Gsa/AC/cAMP/PKA signaling. We developed a knock-in of the recurrent ACRDYS1 R368X PRKAR1A mutation in the mouse. No litters were obtained from [R368X]/[+] females (thus no homozygous [R368X]/[R368X] mice). In [R368X]/[+] mice, Western blot analysis confirmed mutant allele heterozygous expression. Growth retardation, peripheral acrodysostosis (including brachydactyly affecting all digits), and facial dysostosis were shown in [R368X]/[+] mice by weight curves and skeletal measurements (μCT scan) as a function of time. [R368X]/[+] male and female mice were similarly affected. Unexpected, however, whole-mount skeletal preparations revealed a striking delay in mineralization in newborn mutant mice, accompanied by a decrease in the height of terminal hypertrophic chondrocyte layer, an increase in the height of columnar proliferative prehypertrophic chondrocyte layer, and changes in the number and spatial arrangement of proliferating cell nuclear antigen (PCNA)-positive chondrocytes. Plasma PTH and basal urinary cAMP were significantly higher in [R368X]/[+] compared to WT mice. PTH injection increased urinary cAMP similarly in [R368X]/[+] and WT mice. PRKACA expression was regulated in a tissue (kidney not bone and liver) manner. This model, the first describing the germline expression of a PRKAR1A mutation causing dominant repression of cAMP-dependent PKA, reproduced the main features of ACRDYS1 in humans. It should help decipher the specificity of the cAMP/PKA signaling pathway, crucial for numerous stimuli. In addition, our results indicate that PRKAR1A, by tempering intracellular cAMP levels, is a molecular switch at the crossroads of signaling pathways regulating chondrocyte proliferation and differentiation. © 2016 American Society for Bone and Mineral Research.

Carney complex (CNC, OMIM 160980) is a rare dominantly inherited syndrome characterized by the presence of skin pigmentation, myxomas and endocrine tumors. Two-thirds of patients are found to have an inactivating heterozygous germline mutation of the PRKAR1A gene, which encodes the R1alpha regulatory subunit of cyclic-Amp-dependent protein kinase A (1). Approximately 160 index case have been identified (2). This article is protected by copyright. All rights reserved.

Ultrasound scanning is useful to detect neural tube defect (NTD) but scarcely distinguished between closed NTD and open NTD, which had very different prognosis. An amniotic fluid punction is thus mandatory to search for an increase in alpha foeto protein (AFP) levels and for the presence of acetylcholinesterase which identified open NTD. However, AFP levels fluctuate both with the gestational age and the assay used. Our aim was to establish normative values for AFP in amniotic fluid in the second half of pregnancy using three different immunoassays and to improve their clinical relevance. Amniotic fluid punctions were performed on 527 patients from 9 week of gestation (WG) to 37 WG either for maternal age, Trisomy 21 screening, increase in nucal translucency (control group, n = 527) or for suspicion of neural tube defect or abdominal defect (n = 5). AFP was measured using the immunoassay developed for serum AFP on the Access 2 system, the Immulite 2000 and the Advia Centaur. Results were expressed in ng/ml, multiple of the median (MoM) and percentiles. AFP decrease by 1.5 fold between 9 and 19 WG. When NTD was suspected, an increase in anmniotic AFP was observed (from 2.5 MoM to 9.3 MoM) confirming an open NTD. In conclusion, the assay developed on those 3 automates is suitable for the measurement of AFP in amniotic fluid.

Context: Pediatric somatotropinoma is uncommon but usually more aggressive than in adults, creating therapeutic challenges. No treatment guidelines are available. Objectives: To describe the features of pediatric somatotropinomas and to assess therapeutic strategies based on an extensive literature review. Design: We describe a pediatric case of aggressive somatotropinoma with an AIP mutation. We identified 137 pediatric somatotropinoma cases published between 1981 and 2010, and found 41 cases with AIP mutations in the main review. Results: We found a slight male preponderance (59%). Median age was 9 years at symptom onset and 14 years at diagnosis. Macroadenomas accounted for 90% of the tumors; 2/3 of the children had hyperprolactinemia at diagnosis. The first-line treatment was pharmacotherapy in one third and surgery in 2/3 of the patients. Pegvisomant was used in 7 patients and produced significant improvement in 4. The male preponderance was higher in the subgroup with AIP mutations. Mutations leading to severe protein abnormalities were more common than reported in adults. Conclusion: Higher invasiveness and tumor volume in pediatric somatotropinomas require complex treatment combinations, which produce variable results. Pegvisomant is an effective drug whose usefulness in children remains to be determined. Genetic screening, particularly for AIP mutations, should be performed routinely.

Carney complex (CNC) is an autosomal dominant multiple neoplasia, caused mostly by inactivating mutations of the regulatory subunit 1A of the protein kinase A (PRKAR1A). Primary pigmented nodular adrenocortical disease (PPNAD) is the most frequent endocrine manifestation of CNC with a great inter-individual variability. Germline, protein-truncating mutations of phosphodiesterase type 11A (PDE11A) have been described to predispose to a variety of endocrine tumors, including adrenal and testicular tumors.Our objective was to investigate the role of PDE11A as a possible gene modifier of the phenotype in a series of 150 patients with CNC.A higher frequency of PDE11A variants in patients with CNC compared with healthy controls was found (25.3 vs. 6.8%, P0.0001). Among CNC patients, those with PPNAD were significantly more frequently carriers of PDE11A variants compared with patients without PPNAD (30.8 vs. 13%, P = 0.025). Furthermore, men with PPNAD were significantly more frequently carriers of PDE11A sequence variants (40.7%) than women with PPNAD (27.3%) (P0.001). A higher frequency of PDE11A sequence variants was also found in patients with large-cell calcifying Sertoli cell tumors (LCCSCT) compared with those without LCCSCT (50 vs. 10%, P = 0.0056). PDE11A variants were significantly associated with the copresence of PPNAD and LCCSCT in men: 81 vs. 20%, P0.004). The simultaneous inactivation of PRKAR1A and PDE11A by small inhibitory RNA led to an increase in cAMP-regulatory element-mediated transcriptional activity under basal conditions and after stimulation by forskolin.We demonstrate, in a large cohort of CNC patients, a high frequency of PDE11A variants, suggesting that PDE11A is a genetic modifying factor for the development of testicular and adrenal tumors in patients with germline PRKAR1A mutation.

Objectif L’hyperplasie macronodulaire bilaterale des surrenales (HMBS) entraine des tumeurs corticosurrenaliennes bilaterales avec hypercortisolisme. Des alterations du gene ARMC5 (Armadillo Repeat Containing 5) ont ete identifiees chez 20–25 % des patients avec HMBS. ARMC5 est un gene suppresseur de tumeurs mais par des mecanismes inconnus. ARMC5 contient une repetition de domaines Armadillo et un domaine BTB (Bric-a-Brac, Tramtrack, Broad-complex) impliques dans des interactions proteine-proteine. L’identification des proteines qui interagissent avec ARMC5 permettrait de comprendre ses fonctions. Par co-immunprecipitation (co-IP) suivie d’une analyse par spectrometrie de masse nous avons mis en evidence une interaction potentielle entre ARMC5 et CUL3 (Cullin3). Cette interaction est aussi suggeree dans des bases de donnees et par une experience de double hybride recemment publiee. CUL3 est une E3-ubiquitin ligase importante dans l’ubiquitination et la degradation des proteines. Le but de cette etude est de confirmer cette interaction et de comprendre son role. Materiel et methodes Nous avons utilise des co-IP classiques apres expression de CUL3-HA et des experiences de BRET (Bioluminescence Resonance Energy Transfert) pour confirmer l’interaction entre ARMC5 et CUL3. Resultats L’interaction entre ARMC5 et CUL3 a ete confirmee par co-IP et BRET et avons aussi observe qu’une mutation faux-sens localisee dans le domaine BTB (p.L754P) empeche l’interaction entre ARMC5 et CUL3. Discussion L’ensemble de ces donnees montrent que ARMC5 et CUL3 forme un complexe. ARMC5 pourrait participer au processus d’ubiquitination ou serait un substrat de la CUL3. Cela ouvre de nouvelles perspectives dans la physiopathologie des HMBS que nous explorons actuellement.

Background GIP-dependent Cushing's syndrome is caused by ectopic expression of glucose-dependent insulinotropic polypeptide receptor (GIPR) in cortisol-producing adrenal adenomas or in bilateral macronodular adrenal hyperplasias. Molecular mechanisms leading to ectopic GIPR expression in adrenal tissue are not known. Methods We performed molecular analyses on 14 adrenal samples obtained from 12 patients with overt GIP-dependent Cushing's syndrome and from one patient with GIP-dependent aldosteronism. Results Nascent RNA FISH showed that GIPR expression in all adenoma and hyperplasia samples occurred through transcriptional activation of a single allele of the GIPR gene. While no abnormality was detected in proximal GIPR promoter methylation, we identified by CGH-array somatic duplications in chromosome region 19q13.32 containing the GIPR locus in the adrenocortical lesions derived from 3 patients. In 2 adenoma samples, the duplicated 19q13.32 region was rearranged with other chromosome regions, whereas a single tissue sample with hyperplasia had 19q duplication only. These duplications were further confirmed by DNA FISH. Among the 5 genes encompassed in the smallest region of overlap, only GIPR was over expressed. We demonstrated in vitro that juxtaposition with cis-acting regulatory sequences such as glucocorticoid response elements in the newly identified genomic environment drives abnormal expression of the translocated GIPR allele in HEK293 T and H295R cells. Conclusion Altogether, our results provide insight into the molecular pathogenesis of GIP-dependent Cushing's syndrome, occurring through monoallelic transcriptional activation of GIPR driven in some adrenal lesions by structural variations.

PRKAR1A encodes the regulatory subunit type 1-alpha (RIα), of the main mediator of the cAMP effects in the eukaryotic cells – cAMP dependant Protein Kinase A (PKA). Inactivating PRKAR1A mutations are known to be responsible for the multiple neoplasia and lentiginosis syndrome Carney complex (CNC). To date, at least 117 pathogenic variants in PRKAR1A have been identified. The majority of them are subject to non-sense mediated mRNA decay (NMD), leading to PRKAR1A haploinsufficiency and, as a result, activated cAMP signaling in the affected tissues. In recent years it became apparent that CNC may be caused not only by RIα haploinsufficiency, but also by the expression of altered PRKAR1A protein, as proven by analysis of the relatively small proportion of expressed mutations in the gene, consisting of aminoacid substitutions and in-frame genetic alterations. In addition, a new subgroup of mutations that potentially escape NMD and result in CNC through altered rather than missing protein has been analyzed – frame-shifts in the 3′end of the coding sequence that shift the stop codon downstream of the regular one and result in the expression of longer than the wild type protein. The PRKAR1A mutation detection rate in CNC patients is recently estimated at above 60%; PRKAR1A mutation negative CNC patients are characterized by significant phenotypic heterogeneity. In this paper, we present a comprehensive analysis of all 117 known to date pathogenic PRKAR1A sequence variations, and discuss their molecular context and clinical relevance.

Mutations activating the angiotensin II AT1 receptor are important to identify and characterize because they give access to the activation mechanisms of this G protein coupled receptor and help to characterize the signaling pathways and the potential pathophysiology of this receptor. The different constitutively activated mutations of the AT1 receptor are mostly localized in transmembrane domains (TM) and their characterization demonstrated that release of intramolecular constraints and movements among these TM are a necessary step for receptor activation. These mutations constitutively activate Gq linked signaling pathways, receptor internalization and maybe the G protein-independent signaling pathways. Expression of such mutations in mice is linked to hypertension and cardiovascular diseases, but such natural mutations have not been identified in human pathology.

Purpose Adrenocortical tumors, especially cancers, remain challenging both for their diagnosis and prognosis assessment. The aim of this article is to identify molecular predictors of malignancy and of survival. Patients and Methods One hundred fifty-three unilateral adrenocortical tumors were studied by microarray (n = 92) or reverse transcription quantitative polymerase chain reaction (n = 148). A two-gene predictor of malignancy was built using the disease-free survival as the end point in a training cohort (n = 47), then validated in an independent validation cohort (n = 104). The best candidate genes were selected using Cox models, and the best gene combination was validated using the log-rank test. Similarly, for malignant tumors, a two-gene predictor of survival was built using the overall survival as the end point in a training cohort (n = 23), then tested in an independent validation cohort (n = 35). Results Unsupervised clustering analysis discriminated robustly the malignant and benign tumors, and identified two groups of malignant tumors with very different outcome. The combined expression of DLG7 and PINK1 was the best predictor of disease-free survival (log-rank P ≈ 10−12), could overcome the uncertainties of intermediate pathological Weiss scores, and remained significant after adjustment to the Weiss score (P < 1.3 × 10−2). Among the malignant tumors, the combined expression of BUB1B and PINK1 was the best predictor of overall survival (P < 2 × 10−6), and remained significant after adjusting for MacFarlane staging (P < .005). Conclusion Gene expression analysis unravels two distinct groups of adrenocortical carcinomas. The molecular predictors of malignancy and of survival are reliable and provide valuable independent information in addition to pathology and tumor staging. These original tools should provide important improvements for adrenal tumors management.

Angiotensin II AT1 receptor is a G protein coupled receptor, which transduces the physiological effects (vasoconstriction, aldosterone secretion) f this vasoactive peptide. On an evolutionary point of view, this receptor has appeared early in the development of vertebrates, since it is present in cartilagenous fish. It has been duplicated in rodents without any consequence on its functions. It is unlikely that the angiotensin AT2 receptor, whose functions are still debated, has diverged from a common ancestral angiotensin receptor with the AT1 receptor. Numerous activating or inactivating point mutations have been identified by site-directed mutagenesis of the AT1 receptor sequence. However, such natural mutations do not appear to be frequent in the genesis of human diseases or in the diversity of phenotypic traits.

Numerous clinical studies and experimental investigations using cell culture and animal models suggest that angiotensin II (AngII) via AT(1) receptor activation might induce cardiovascular hypertrophy, fibrosis and atherosclerosis resulting in vascular events such as myocardial infarction, heart failure or stroke and in end-organ damages. However, a question still remains: which part of these damages is due to a direct effect of AngII on its target tissues and which is due to AngII-induced hypertension? In an attempt to answer this question, a new model of transgenic mice, expressing a constitutively activated AT(1A) receptor instead of the wild type receptor has been obtained by homologous recombination. These mice present with a moderate increase of blood pressure (20 mm Hg), hypertrophy of the small kidney arteries but not cardiac hypertrophy. The major phenotypic trait of these mice is the early and progressive development of a cardiovascular fibrosis. In light of these results and those from the literature, there is more and more evidence that in human hypertension, activation of the renin angiotensin system plays a minor role in the development of cardiovascular hypertrophy, but clearly participates to the development of cardiovascular fibrosis.

The role of the renin-angiotensin system has been investigated by overexpression or inactivation of its different genes in animals. However, there is no data concerning the effect of the constitutive activation of any component of the system. A knockin mouse model has been constructed with a gain-of-function mutant of the Ang II receptor, type 1A (AT(1A)), associating a constitutively activating mutation (N111S) with a C-terminal deletion, which impairs receptor internalization and desensitization. In vivo consequences of this mutant receptor expression in homozygous mice recapitulate its in vitro characteristics: the pressor response is more sensitive to Ang II and longer lasting. These mice present with a moderate (~20 mmHg) and stable increase in BP. They also develop early and progressive renal fibrosis and cardiac fibrosis and diastolic dysfunction. However, there was no overt cardiac hypertrophy. The hormonal parameters (low-renin and inappropriately normal aldosterone productions) mimic those of low-renin human hypertension. This new model reveals that a constitutive activation of AT(1A) leads to cardiac and renal fibrosis in spite of a modest effect on BP and will be useful for investigating the role of Ang II in target organs in a model similar to some forms of human hypertension.

Objective: Germline mutations of the aryl hydrocarbon receptor-interacting protein gene (AIP) have recently been described in three families with GH or prolactin-secreting tumors, as well as in a few patients with apparently sporadic somatotropinomas. The aim of the study was to determine the prevalence of AIP mutations in a large cohort of patients with apparently sporadic GH-secreting tumors. Design: One hundred and fifty-four patients were included in a prospective cohort designed to study the genetic predisposition to GH-secreting tumors together with 270 controls. Methods: In all these subjects, the entire coding sequence of the AIP gene was screened for germline mutations. Results: AIP mutations were detected in 5 out of 154 patients (3%): nonsense mutations in exon 4 (p.Lys201X; n = 2) and in exon 6 (p.Arg304X), one deletion in exon 3 (c.404delA; pHis135LeufsX21), and one mutation affecting the splice acceptor site of exon 4 (c.469-2 A > G). The five patients with an AIP mutation were significantly younger (mean age ± S.D.: 25 ± 10 vs 43 ± 14 years, P = 0.005) and three of them presented with gigantism. One missense mutation (p.Arg304Gln) was found in a single patient that was absent in all controls. Conclusions: Germline mutations of the AIP gene were found in a small proportion of patients with sporadic pituitary somatotropinomas. This study shows that age and gigantism are simple clinical features which can help to select patients for mutation screening. It also supports the role of AIP in pituitary tumorigenesis.

BackgroundMEN1, which is secondary to the mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Most studies demonstrated the absence of direct genotype-phenotype correlations. The existence of a higher risk of death in the Groupe d'étude des Tumeurs Endocrines-cohort associated with a mutation in the JunD interacting domain suggests heterogeneity across families in disease expressivity. This study aims to assess the existence of modifying genetic factors by estimating the intrafamilial correlations and heritability of the six main tumor types in MEN1.MethodsThe study included 797 patients from 265 kindred and studied seven phenotypic criteria: parathyroid and pancreatic neuroendocrine tumors (NETs) and pituitary, adrenal, bronchial, and thymic (thNET) tumors and the presence of metastasis. Intrafamilial correlations and heritability estimates were calculated from family tree data using specific validated statistical analysis software.ResultsIntrafamilial correlations were significant and decreased along parental degrees distance for pituitary, adrenal and thNETs. The heritability of these three tumor types was consistently strong and significant with 64% (s.e.m.=0.13; Ps.e.m.=0.21; Ps.e.m.=0.41; P=0.006) for thNETs.ConclusionThe present study shows the existence of modifying genetic factors for thymus, adrenal, and pituitary MEN1 tumor types. The identification of at-risk subgroups of individuals within cohorts is the first step toward personalization of care. Next generation sequencing on this subset of tumors will help identify the molecular basis of MEN1 variable genetic expressivity.

The renin-angiotensin-aldosterone system (RAAS) is central to cardiovascular and renal physiology. However, there is no animal model in which the activation of the RAAS only reflects the activation of the angiotensin II (ANG II) AT1receptor. As a first step to developing such a model, we characterized a gain-of-function mutant of the mouse AT1Areceptor. This mutant carries two mutations: N111S predicted to activate the receptor constitutively and a COOH-terminal deletion, Δ329, expected to reduce receptor internalization and desensitization. We expressed this double mutant (AT1A-N111S/Δ329) in heterologous cells. It showed a pharmacological profile consistent with that of other constitutively active mutants. Furthermore, it increased basal production of inositol phosphates, as well as basal cytosolic and nuclear ERK activities. Basal proliferation of cells expressing the mutant was also greater than that of the wild type. The double mutant was poorly internalized and failed to recruit β-arrestin 2 in the presence of ANG II. It also showed hypersensitive and hyperreactive responses to ANG II for both inositol phosphate production and ERK activation. The additivity of the phenotypes of the two mutations makes this mutant an appropriate candidate to test the physiological consequences of the AT1Areceptor activation itself in transgenic animal models.

Resume Les recepteurs hormonaux membranaires sont repartis en trois grandes familles : les recepteurs couples aux proteines G, les recepteurs tyrosine kinase et les recepteurs des cytokines. Chacune de ces familles est caracterisee par des proprietes structurales communes et des mecanismes de transduction du signal particuliers.

Resume Les techniques de biologie utilisees en endocrinologie sont indissociables de la clinique : dosage immunologique et biologie moleculaire sont aujourd'hui realises en routine. En comprendre les principes est essentiel pour une bonne interpretation des resultats. Les outils de pharmacologie sont utiles en endocrinologie afin de caracteriser le devenir d'une hormone dans l'organisme apres sa secretion, et l'action de cette hormone sur ses cibles.

International audience; Insulin-like growth factor 2 (IGF2) overexpression is an important molecular marker of adrenocortical carcinoma (ACC), which is a rare but devastating endocrine cancer. It is not clear whether IGF2 overexpression modifies the biology and growth of this cancer, thus more studies are required before IGF2 can be considered as a major therapeutic target. We compared the phenotypical, clinical, biological, and molecular characteristics of ACC with or without the overexpression of IGF2, to address these issues. We also carried out a similar analysis in an ACC cell line (H295R) in which IGF2 expression was knocked down with si- or shRNA. We found no significant differences in the clinical, biological and molecular (transcriptomic) traits between IGF2-high and IGF2-low ACC. The absence of IGF2 overexpression had little influence on the activation of tyrosine kinase pathways both in tumors and in H295 cells that express low levels of IGF2. In IGF2-low tumors, other growth factors (FGF9, PDGFA) are more expressed than in IGF2-high tumors, suggesting that they play a compensatory role in tumor progression. In addition, IGF2 knock-down in H295R cells substantially impaired growth (>50% inhibition), blocked cells in G1 phase, and promoted apoptosis (>2-fold). Finally, analysis of the 11p15 locus showed a paternal uniparental disomy in both IGF2-high and IGF2-low tumors, but low IGF2 expression could be explained in most IGF2-low ACC by an additional epigenetic modification at the 11p15 locus. Altogether, these observations confirm the active role of IGF2 in adrenocortical tumor growth, but also suggest that other growth promoting pathways may be involved in a subset of ACC with low IGF2 expression, which creates opportunities for the use of other targeted therapies.

French COMETE Network (R.L.), 75014 Paris, France; Centre for Endocrinology, Diabetes and Metabolism, School of Clinical and Experimental Medicine (W.A.), University of Birmingham, Birmingham B15 2TT, United Kingdom; INSERM U982 (E.L.), Differenciation & Communication Neuronale & Neuroendocrine, Universite de Rouen, 76821 Mont-Saint-Aignan, France; Departments of Endocrinology (C.W., L.G.), Hormonal Biology (J.G.), Pathology (M.S.), and Oncogenetics (E.C.), Hopital Cochin, Universite Paris Descartes, Sorbonne Paris Cite, 75006 Paris, France; and INSERM U1016 (L.G.), Institut Cochin, 75014 Paris, France

International audience; Adrenocortical carcinomas (ACCs) are aggressive cancers originating in the cortex of the adrenal gland. Despite overall poor prognosis, ACC outcome is heterogeneous. We performed exome sequencing and SNP array analysis of 45 ACCs and identified recurrent alterations in known driver genes (CTNNB1, TP53, CDKN2A, RB1 and MEN1) and in genes not previously reported in ACC (ZNRF3, DAXX, TERT and MED12), which we validated in an independent cohort of 77 ACCs. ZNRF3, encoding a cell surface E3 ubiquitin ligase, was the most frequently altered gene (21%) and is a potential new tumor suppressor gene related to the β-catenin pathway. Our integrated genomic analyses further identified two distinct molecular subgroups with opposite outcome. The C1A group of ACCs with poor outcome displayed numerous mutations and DNA methylation alterations, whereas the C1B group of ACCs with good prognosis displayed specific deregulation of two microRNA clusters. Thus, aggressive and indolent ACCs correspond to two distinct molecular entities driven by different oncogenic alterations.

The angiotensin II (Ang II) AT1A receptor was tagged at its C terminus with the enhanced green fluorescent protein (EGFP), and the corresponding chimeric cDNA was expressed in HEK-293 cells. This tagged receptor presents wild-type pharmacological and signaling properties and can be immunodetected by Western blotting and immunoprecipitation using EGFP antibodies. Therefore, this EGFP-tagged AT1A receptor is the perfect tool for analyzing in parallel the subcellular distributions of the receptor and its interacting G protein and their trafficking using confocal microscopy. Morphological observation of both the fluorescent receptor and its cognate Gαq/11 protein, identified by indirect immunofluorescence, and the development of a specific software for digital image analysis together allow examination and quantification of the cellular distribution of these proteins before and after the binding of different agonist or antagonist ligands. These observations result in several conclusions: 1) Expression of incre...

The regulation of the thyroid gland by TSH is mediated by a heterotrimeric G protein-coupled receptor. Nonthyroid effects of TSH have been reported, and expression of its receptor has been described in adipocytes and lymphocytes. We have previously reported the existence of specific and saturable binding sites of TSH and specific TSH effects in primary cultured rat brain astroglial cells. We now report expression of the TSH receptor gene in these cells; the coding sequence of the corresponding complementary DNA is identical to that previously established in thyroid. Using specific antisense RNA probe, expression of this gene was detected in some isolated or clustered glial fibrillary acidic protein-positive primary cultured cells by in situ hybridization. With this technique, we further detected TSH receptor messenger RNA (mRNA) expression in rat brain cryoslices in both neuronal cells and astrocytes. Its presence predominated in neuron-rich areas (pyriform and postcingulate cortex, hippocampus, and hypothalamic nuclei) and was mostly colocalized with neuron-specific enolase. In astrocytes, this mRNA was detected in the ependymal cell layer and the subependymal zone, and several isolated cells were also found in the brain parenchyma. We also detected TSH receptor mRNA and protein in primary cultured human astrocytes. The protein was detected as well in both rat and human brain cryoslices. Together, these findings clearly demonstrate the expression of the TSH receptor gene in the brain in both neuronal cells and astrocytes.

The gene of the mouse V3/V1b receptor was identified by homology cloning. One of the genomic clones contained the entire coding sequence. The cDNA presented high identity with rat (92%) and human (84%) sequences. Southern blot analysis indicated the existence of a single gene. Tissue distribution was studied by RT-PCR. The major site of expression was the pituitary. A faint signal was also present in hypothalamus, brain, adrenal, pancreas and colon. The mouse corticotroph cell line, AtT20, did not express the transcript. In order to confirm the identity of the sequence, the V3/V1b receptor cDNA was cloned and stably expressed in CHO-AA8 Tet-Off cells under the control of tetracycline. When transfected cells were treated with arginine vasopressin (AVP), inositol phosphate production increased in a dose-dependent manner, indicating that the V3/V1b receptor couples to phospholipase C. Moreover, AVP did not stimulate cAMP production. Binding studies with [3H]AVP indicated that the affinity of the mouse V3/V1b receptor (Kd=0.5 nM) is similar to that reported for rat and human receptors. The rank order of potency established in competition binding experiments with different analogues was representative of a V3/V1b profile, distinct from V1a and V2. However, significant differences were found between human and mouse receptors tested in parallel. Thus the pharmacology of V3/V1b receptors can not be transposed among different species.

Les myxomes cardiaques sont des tumeurs benignes generalement sporadiques. Les formes familiales, plus rares, sont associees au complexe de Carney (CNC). Une mutation germinale de PRKAR1A, codant pour la sous-unite regulatrice R1a de la PKA, est retrouvee chez 62 % des patients CNC et 83 % si ces derniers ont un myxome cardiaque parmi leurs atteintes. Objectif Evaluer la prevalence des mutations germinales de PRKAR1A dans les myxomes cardiaques isoles sporadiques. Patients et methodes Quarante-huit patients majeurs ayant ete operes de myxome cardiaque, ont participe a l’etude. Une consultation specialisee s’assurait de la presentation sporadique et isolee, et du prelevement sanguin. L’ensemble des sequences transcrites du gene PRKAR1A a ete etudie par sequencage direct et la recherche de grandes deletions par MLPA. Resultats La population etudiee est similaire a une population de myxomes sporadiques : une predominance feminine (29F, sexe ratio 1,5), un âge moyen de 61,5 ans (± 11,2, range 31–89) et les myxomes sont principalement de l’oreillette gauche (84 %). Une variation faux-sens est retrouvee chez un patient de 50 ans p.Arg74His (c.221G>A) ; cet acide amine est porteur d’une mutation faux-sens pathogene publiee p.Arg74Cys (Veugelers PNAS 2004). Une variation intronique proche du site de splice non connue comme SNP, est decouvert chez deux patients (c.552-18A > G). Discussion Les mutations classiques du CNC semblent absentes dans le myxome isole de l’adulte, en l’absence de tout element clinique evocateur de CNC. Cependant, des variants dont la pathogenicite reste a etudier sur le plan fonctionnel sont mis en evidence.

We studied the putative role of the vasopressin receptors in the phenotypic response of steroid-secreting adrenocortical tumors. A retrospective analysis of a series of 26 adrenocortical tumors responsible for Cushing’s syndrome (19 adenomas and 7 carcinomas) showed that vasopressin (10 IU, im, lysine vasopressin) induced an ACTH-independent cortisol response (arbitrarily defined as a cortisol rise above baseline of 30 ng/mL or more) in 7 cases (27%). In comparison, 68 of 90 patients with Cushing’s disease (76%) had a positive cortisol response. We then prospectively examined the expression of vasopressin receptor genes in adrenocortical tumors of recently operated patients (20 adenomas and 19 adrenocortical carcinomas). We used highly sensitive and specific quantitative RT-PCR techniques for each of the newly characterized human vasopressin receptors: V1, V2, and V3. The V1 messenger ribonucleic acid (mRNA) was detected in normal adrenal cortex and in all tumors. Its level varied widely between 2.0 × 102...

The structural determinants of the rat angiotensin (ANG) II AT1Areceptor involved in receptor internalization, desensitization, and activation are investigated by producing six mutants that had progessively larger deletions of the cytoplasmic tail (−13, −19, −24, −31, −46, and −56 residues, respectively). After stable transfection of the cDNAs into Chinese hamster ovary cells, all mutants, except the most truncated, exhibit normal [Sar1]ANG II affinities [dissociation constant ( Kd) = 0.19–0.70 nM] compared with the wild-type (WT) receptor ( Kd= 0.62 nM) and are able to activate a Gq/11protein and a phospholipase C as measured by the ANG II-induced inositol phosphate (IP) turnover in the different clones. However, one of these mutants, Δ329 (deletion of 31 residues), exhibits a peculiar phenotype. This mutant shows a reduced ligand-induced internalization as measured by the acid-washing procedure (only 32% of receptors are internalized vs. 83% for WT). Moreover, the Δ329 mutant is less desensitized by a pretreatment with either ANG II (15% desensitization of ANG II-stimulated IP turnover vs. 60% for WT receptor) or the phorbol ester phorbol 12-myristate 13-acetate (no desensitization vs. 29% for WT receptor). These functional modifications of the Δ329 mutant are associated with the transduction of an amplified signal as demonstrated on both IP turnover and an integrated physiological effect of ANG II. Taken together, these data indicate that the sequence329SLSTKMS335of the rat AT1Areceptor is involved in both receptor internalization and desensitization. This is the first demonstration that a desensitization- and internalization-defective AT1Areceptor mutant is also hyperreactive and mediates augmented cellular responses.