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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Primärer Aldosteronismus

Jasper, Theres, January 1968 (has links)
Inaug.-Diss.--Bonn. / Vita. Includes bibliographical references.
2

Low-renin hypertension : characterization of Conn's syndrome identifies subtypes of aldosterone-producing adenomas

Azizan, Elena Aisha Binti January 2013 (has links)
No description available.
3

Genetic, Diagnostic and Therapeutic Aspects of Primary Aldosteronism

Norlela Sukor Unknown Date (has links)
Background: Primary aldosteronism (PAL) has emerged as the commonest specifically treatable and potentially curable form of secondary hypertension. With its propensity towards cardiovascular complications above that expected from hypertension alone, PAL is a potentially highly detrimental state which should be detected as early as possible in the course of the disease and treated appropriately. The detection of earlier, milder, normokalaemic forms of PAL using the aldosterone/renin ratio (ARR) as a screening test has significantly enlarged the clinical spectrum of PAL and facilitated identification of a new familial variety (familial hyperaldosteronism type II, FH-II). Unlike familial hyperaldosteronism type I (FH-I), FH-II is not glucocorticoid remediable and is not caused by the CYP11B1/CYP11B2 “hybrid” gene mutation. The genetic defects underlying FH-II have not yet been elucidated and hence, detection of FH-II still involves complicated and time-consuming biochemical screening by ARR testing and confirmation by carefully performed suppression testing such as fludrocortisone suppression testing. Diagnosing PAL by currently available biochemical methods is tedious. Finding a simple and reliable genetic test for FH-II which could be applied to all members of a family with known FH-II and also to apparently sporadic PAL would simplify patient management. A genome-wide search has already demonstrated linkage of FH-II to chromosome 7p22, consistent with this locus harbouring the causative gene/s for FH-II. Three candidate genes [retinoblastoma-associated Kruppel-associated box gene (RBaK, involved in tumorigenesis and cell cycle control), postmeiotic segregation increased 2 (PMS2, involved in DNA mismatch repair and tumour predisposition) and guanine nucleotide-binding protein alpha-12 (GNA12, a transforming oncogene)] within this linked locus have been examined in an attempt to find the causative mutations for FH-II, but no clear causative mutations have so far been found. PAL continues to be a challenging yet rewarding disease to manage. Although much has been learnt about PAL, there are still many areas which have not been explored. PAL considered due to bilateral autonomous production of aldosterone is usually treated medically because unilateral adrenalectomy has been considered ineffective. Since medical treatment may cause adverse effects or fail to control hypertension, defining the role of unilateral adrenalectomy in bilateral PAL is an important clinical issue, but quality outcome data are lacking. The candidate therefore peformed a retrospective study of the efficacy of unilateral adrenalectomy in patients with bilateral PAL. In patients with unilateral PAL, unilateral laparoscopic adrenalectomy has been shown to correct hypokalaemia and lead to cure or improvement in hypertension control. While most studies have focused on clinical and biochemical outcomes, to the candidate’s knowledge, there are no data on the effects of adrenalectomy on quality of life (QOL). Assessing the QOL in patients with unilateral PAL before and after unilateral laparoscopic adrenalectomy (which cured hypokalaemia in all and hypertension in the majority) provided an insight into the degree to which the disease process and/or its treatment affects the life of an individual with PAL. Aims: The overall aims of this thesis were to further explore the genetic basis of FH-II, to examine the role of adrenalectomy in patients with bilateral PAL and the effects of unilateral adrenalectomy on QOL in unilateral PAL as a first step in dissecting out the effects of medical and surgical treatment on QOL in the more common bilateral PAL. In order to address the overall aims, the specific aims of the thesis were (1) to narrow the linked region at 7p22 by phenotyping and genotyping additional FH-II families from Italy, using more closely spaced microsatellite markers at 7p22, and then assess the combined multipoint logarithm of odds (LOD) score for these Italian as well as two Australian and one South American families; (2) to sequence candidate genes in the narrowed linked region for FH-II associated mutations; (3) to assess the role of unilateral adrenalectomy in bilateral PAL and identify predictive parameters; and (4) to assess the quality of life following unilateral adrenalectomy in patients with unilateral PAL. Methods and Results: Two Italian families with FH-II were genotyped using seven closely spaced microsatellite markers at 7p22. All known affected individuals from each of the two Italian families were found to share identical haplotypes for the seven markers, consistent with linkage of the disease locus with the 7p22 region. The multipoint LOD score of the now five known families with FH-II which demonstrate linkage at 7p22, calculated using MERLIN linkage analysis was highly significant at 5.22. Three candidate genes in this linked region were then examined for mutations causing FH-II; the replication protein A 3 (RPA3), zinc finger protein 12 (ZNF12) and glucocorticoid induced transcripts 1 (GLCCI1) genes were selected as they are involved in cell cycle control, and adrenal hyperplasia and adenomas are common in FH-II. Using the method of polymerase chain reaction-sequencing, coding regions, splice sites, proximal promoter, 5’ and 3’ untranslated regions (UTR) were sequenced in affected and unaffected subjects from the 7p22-linked FH-II families. Identified single nucleotide polymorphisms (SNPs) were genotyped to assess significance. For RPA3, four different SNPs were initially found to segregate with the affectation status, that is, they were present in the two affected and not the two unaffected subjects from the largest Australian family (family 1, eight affecteds) with FH-II. However, only two SNPs (rs2024374 G/C and rs17169194 T/G) were further genotyped as that they were in functionally important positions of the gene (that is, in regulatory regions within the promoter and 5’ UTR) and because of the relatively low allele frequency reported in the literature for these two SNPs in controls. Further genotyping of these SNPs was carried out in another six affecteds and four unaffecteds from the same family and a complete segregation of these two SNPs with affectation status was seen in family 1. The G/C mutation rs2024374 in the RPA3 promoter results in the loss of three transcription factor binding sites and creation of one new site. The factors for which the binding sites in the RPA3 promoter and 5’UTR were altered by these two SNPs were involved in regulation of cell differentiation, proliferation and apoptosis. Hence, it is possible that altered activity of the RPA3 promoter and 5’UTR in family 1 could result in predisposition to adrenal hyperplasia or neoplasia, altered ARR and/or hypertension. Genotyping of these SNPs was then carried out in another two pedigrees (families 2 and 3) that showed linkage to 7p22, and in 75 normotensive, non-PAL control subjects. However, neither of these two SNPs segregated with the affectation status in family 2 and 3, and they were present in 30% and 20% of controls, respectively. For ZNF12 and GLCCI1, no evidence of causative mutations was found in the coding regions, splice sites, proximal promoter region and proximal 5’ and 3’ UTR. Between 1984 and 2004, 51 of 684 patients diagnosed with bilateral PAL underwent unilateral adrenalectomy. Forty patients fulfilled the inclusion criteria and were followed for at least 12 (median 56.4) months. Hypertension was cured in 15% and improved in 20%, usually within one year of unilateral adrenalectomy. The proportion with controlled hypertension was significantly (p<0.001) higher after adrenalectomy (65%) than before (25%). Mean systolic (p<0.001) and diastolic (p<0.001) blood pressure, left ventricular mass index (p<0.05) and aldosterone/renin ratio (p<0.001) fell. Serum creatinine independently predicted hypertension cure. From 2007 through 2008, QOL was evaluated prospectively using the internationally validated SF-36 questionnaire before and 3 and 6 months post-operatively in 22 patients [14 males, 8 females; mean age 50.0 ± 2.0 (range 27-69) years] with unilateral PAL who underwent adrenalectomy within the Endocrine Hypertension Centre, Greenslopes and Princess Alexandra Hospitals. Pre-operatively, the SF36 score for each QOL domain was lower for PAL patients than reported for the Australian general population, significantly so for physical functioning (p<0.05), role physical (p<0.001), vitality (p<0.001) and general health (p<0.05). Compared with pre-adrenalectomy, there were significant increments in mean scores at 3 months for physical functioning (p<0.05), role physical (p<0.05), general health (p<0.001), role emotional (p<0.05), social functioning (p<0.05), mental health (p<0.001) and vitality (p<0.001); and at 6 months for physical functioning (p<0.05), role physical (p<0.05), general health (p<0.05), role emotional (p<0.05), mental health (p<0.05) and vitality (p<0.001). Mean SBP and DBP improved significantly (p<0.001), with 86% of these patients cured (BP≤140/90, no drugs) and the remaining 14 % improved. Mean plasma potassium (p<0.001) and renin concentration rose (p<0.01), whereas mean upright plasma aldosterone (p<0.001), aldosterone/renin ratio (p<0.001) and number of antihypertensive agents fell (p<0.001). Conclusion: In the Italian families with FH-II available for study, work by the candidate included in this thesis confirmed linkage of FH-II to chromosome 7p22. The combined multipoint LOD score of 5.22 for the five families showing linkage at 7p22 was highly significant. Linkage to 7p22 in Italian families with FH-II extends the previous positive findings to a third geographical area, bringing greater certainty regarding the importance of this locus in identifying causative mutations. Although no clear causative mutations were found in the three 7p22 candidate genes examined, it is conceivable that the rs2024374 G/C and/or rs17169194 T/G SNPs in RPA3 could act in conjunction with another 7p22 mutation in family 1, resulting in the FH-II phenotype. Examination of the outcome of unilateral adrenalectomy in patients with bilateral PAL suggests that this surgical approach can be beneficial in certain carefully selected patients and should not be automatically excluded as a treatment option. Unilateral adrenalectomy in patients with unilateral PAL has positive impacts not only on clinical and biochemical parameters but also on QOL. The findings of this thesis provide new insights into the genetic basis and therapeutic options and treatment outcomes of PAL and further highlight its importance as a common, genetically based, specifically treatable and potentially curable cause of hypertension and cardiovascular disease. It also points the way to potentially very useful studies in future by exploring longer term effects of unilateral laparoscopic adrenalectomy as treatment for PAL on QOL, to compare unilateral adrenalectomy in those with unilateral versus bilateral PAL, and to compare surgery with specific medical treatment.
4

Prevalence of Cardiovascular Disease and Its Risk Factors in Primary Aldosteronism: A Multicenter Study in Japan / わが国の原発性アルドステロン症患者の心血管イベント有病率と発症に関わる因子

Ohno, Youichi 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21677号 / 医博第4483号 / 新制||医||1036(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 中山 健夫, 教授 木村 剛, 教授 湊谷 謙司 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
5

Investigação genética dos tumores corticais adrenais produtores de aldosterona / Genetic investigation of aldosterone-producing adrenocortical tumors

Vilela, Letícia Assis Pereira 03 July 2019 (has links)
Introdução: O hiperaldosteronismo primário (HP) é a causa mais comum de hipertensão arterial sistêmica (HAS) secundária, com prevalência de até 21% em pacientes com HAS resistente. Na última década, foram feitos consideráveis avanços na compreensão da patogênese do HP. Variantes patogênicas somáticas nos genes de canais iônicos KCNJ5, CACNA1D, ATP1A1 e ATP2B3, envolvidos na manutenção da homeostase iônica intracelular, foram descritas em 38%, 9,3%, 5,3% e 1,7% dos tumores, respectivamente. Variantes patogênicas somáticas no gene CTNNB1, fundamental para o desenvolvimento do córtex da suprarrenal, foram também identificadas em aproximadamente 5% dos aldosteronomas. Mais recentemente, uma variante germinativa no gene CACNA1H, que codifica a subunidade Alfa1H do canal de cálcio Cav 3.2, foi identificada em um paciente com aldosteronoma. Objetivos: O objetivo geral desse projeto foi investigar as bases genéticas do HP causado por aldosteronoma. Os objetivos específicos foram: 1) Investigar variantes patogênicas somáticas nos genes KCNJ5, ATP1A1, ATP2B3 e CTNNB1 em aldosteronomas de indivíduos com HP; 2) Sequenciar o exoma (pareado sangue e tumor) dos casos de HP causados por aldosteronoma, negativos para variantes nos genes citados acima; 3) Correlacionar o genótipo com os parâmetros clínicos e hormonais dos pacientes com aldosteronomas. Métodos: As regiões hot-spot dos genes KCNJ5, ATP1A1, ATP2B3 e CTNNB1 foram sequenciadas por Sanger em 62 tumores [56% mulheres; mediana de idade ao diagnóstico 50 anos (variação, 20 a 68)]. Pacientes sem variantes patogênicas somáticas nos genes descritos acima foram submetidos a genotipagem do exoma (pareado sangue e tecido) por sequenciamento paralelo em larga escala (HiSeq 2500, Illumina). Variantes germinativas raras (MAF < 0,01% no 1000 genomes, ExAC, gnomAD e AbraOM) em genes codificadores de canais iônicos ou associados a hiperplasia adrenal foram selecionadas para segregação familial. Resultados: Variantes patogênicas somáticas em heterozigose foram encontradas em 34 de 62 (54,8%) aldosteronomas. As variantes identificadas nos genes KCNJ5, ATP1A1, ATP2B3 e CTNNB1 eram previamente conhecidas. Variantes patogênicas no KCNJ5 foram detectadas em 28 de 62 (45,2%) aldosteronomas. Duas variantes recorrentes foram encontradas: p.Gly151Arg em 13 de 28 (46%) e p.Leu168Arg em 14 de 28 (50%) tumores. A variante patogênica p.Glu145Gln do KCNJ5 foi identificada em um (4%) aldosteronoma. Adicionalmente, a variante patogênica p.Leu104Arg do ATP1A1 foi detectada em 2 (3,2%) aldosteronomas; a variante patogênica p.Leu425_Val426del do ATP2B3 em um (1,6%) caso e a variante patogênica p.Ser45Pro do CTNNB1 em 2 (3,2%) aldosteronomas. Uma nova variante p.Leu276Pro somática em heterozigose no CACNA1D foi identificada em um aldosteronoma no exoma e classificada como provavelmente patogênica. Aldosteronomas com variantes patogênicas no KCNJ5 foram diagnosticados mais frequentemente em mulheres (p= 0,047) e em idades mais jovens (p= 0,002) quando comparado com tumores sem variantes no KCNJ5. O tamanho do nódulo foi maior em aldosteronomas com variantes patogênicas no KCNJ5 (p= 0,0001). O percentual de pacientes com tempo de HAS < 5 anos foi similar nos dois grupos. A remissão pós-operatória da HAS foi observada em 50% dos pacientes com tumor contendo variante patogênica no KCNJ5, enquanto apenas 15% dos pacientes com tumor sem variante no KCNJ5 tiveram remissão da HAS (p= 0,003). Na análise multivariada, somente a presença de variante patogênica somática no KCNJ5 foi um preditor independente de remissão da HAS (p= 0,03). Após filtragem das variantes encontradas no sequenciamento exômico, quatro variantes germinativas missense em heterozigose foram consideradas deletérias em mais de 3 algoritmos de predição in silico: 1) uma nova variante (p.Pro559Thr) no gene CACNA1H, já associado ao fenótipo de HP; 2) a variante p.Arg178Cys no gene CACNA1I, que codifica a subunidade Alfa 1I do canal Cav 3.3; 3) a variante p.Glu52Ala no gene ATP13A3, que codifica uma proteína transmembrana da família de proteínas ATPase do tipo P; 4) a variante p.Tyr507Ser no gene KCNC4, que codifica o canal de potássio Kv 3.4. Conclusão: Foi caracterizado o espectro de variantes patogênicas somáticas em uma coorte brasileira de tumores corticais adrenais produtores de aldosterona, bem como o impacto das variantes no KCNJ5 na predição de remissão da HAS após adrenalectomia. Além disso, foram identificados novos genes candidatos provavelmente relacionados a patogênese do HP causado por aldosteronomas / Introduction: Primary aldosteronism (PA) is the most common form of secondary hypertension (HT), with a prevalence of approximately 20% in patients with resistant hypertension. In the last decade, somatic mutations in KCNJ5, CACNA1D, ATP1A1 and ATP2B3 genes, which are involved in maintaining intracellular ionic homeostasis and cell membrane potential, were described in 38%, 9.3%, 5.3% and 1.7% of aldosterone-producing adenomas (APAs), respectively. All these mutations lead to the activation of calcium signaling, the major trigger for aldosterone production. Additionally, somatic activating mutations in exon 3 of CTNNB1 gene, which is involved in the adrenocortical development, were identified in approximately 5% of APAs. More recently, the germline p.V1951G CACNA1H variant was described in a PA patient with an APA. Aims: To investigate the genetics of APAs. The specific aims of this study were: 1) To investigate somatic variants in KCNJ5, ATP1A1, ATP2B3 and CTNNB1 genes in APAs from PA patients; 2) To perform exome sequencing of PA patients caused by APAs without mutations in those genes already associated with PA; 3) To correlate genetic findings and clinical parameters. Methods: Hot-spot regions of KCNJ5, ATP1A1, ATP2B3 e CTNNB1 genes were sequenced by Sanger in 62 APAs [56% women; median of age at diagnosis 50 yrs (range, 20 to 68)]. We performed whole exome sequencing (HiSeq 2500, Illumina) in paired blood and tumor DNA samples from 10 unrelated subjects with PA caused by APAs without somatic mutations in hot-spot regions of KCNJ5, ATP1A1, ATP2B3 and CTNNB1.We searched for rare germline coding variants (MAF < 0.01% in 1000 genomes, ExAC, gnomAD and AbraOM) in ionchannel genes, which are expressed in normal adrenal tissue, or in genes previously related to adrenal hyperplasia. Results: Pathogenic somatic heterozygous variants were identified in 34 out of 62 (54.8%) APAs. KCNJ5 pathogenic variants were detected in 28 out of 62 (45.2%) APAs. Two recurrent variants were found in KCNJ5: the p.Gly151Arg in 13 out of 28 (46%) and the p.Leu168Arg in 14 out of 28 (50%) APAs. KCNJ5 pathogenic variant p.Glu145Gln was identified in one (4%) APA. In addition, the p.Leu104Arg ATP1A1 mutation was detected in two APAs (3.2%); the p.Leu425_Val426del ATP2B3 mutation in one APA (1.6%); and the p.Ser45Pro CTNNB1 mutation in two APAs (3.2%). The novel CACNA1D somatic heterozygous variant p.Leu276Pro (likely pathogenic) was identified by exome sequencing in one APA. APAs with KCNJ5 pathogenic variants were diagnosed more often in women (p= 0.047) and at younger ages (p= 0.002) when compared to APAs without KCNJ5 variants. Nodule size was larger in APAs with KCNJ5 pathogenic variants (p= 0.0001). The frequency of PA patients com HT duration < 5 yrs was similar in both groups. HT remission was observed in 50% of patients with APAs harboring KCNJ5 pathogenic variants, whereas only 15% of patients with APAs without KCNJ5 pathogenic variants had HT remission (p= 0.003). In multivariate analysis, only the presence of a KCNJ5 pathogenic variant was an independent predictor of HT remission (p= 0.03). After exome sequencing analysis, four germline missense heterozygous variants predicted to be pathogenic in >=3 in silico tools were selected: 1) the novel p.Pro559Thr variant in CACNA1H gene, previously associated with PA phenotype; 2) the p.Arg178Cys variant in CACNA1I gene, which encodes the Alpha 1I subunit of Cav 3.3 channel; 3) the p.Glu52Ala variant in ATP13A3 gene, which is a member of the P-type ATPase family of membrane transport proteins; and 4) the p.Tyr507Ser variant in KCNC4 gene, which encodes the voltage-gated potassium channel Kv 3.4. Conclusion: We have characterized the spectrum of somatic pathogenic variants in a Brazilian cohort of APAs, and evaluated the impact of KCNJ5 somatic pathogenic variants in predicting HT remission after adrenalectomy. In addition, we identified potential novel gene candidates in the pathogenesis of PA caused by APAs
6

The regulation of T-type calcium channels by G protein [beta][gamma] dimers /

DePuy, Seth David. January 2007 (has links)
Thesis (Ph. D.)--University of Virginia, 2008. / Includes bibliographical references. Also available via the Internet as viewed 10 July 2008.
7

Functional and diagnostic aspects on adrenocortical adenoma /

Enberg, Ulla, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
8

Rôle de la voie Wnt/ßcaténine dans la physiopathologie de la cortico-surrénale / Role of the Wnt/ßcatenin pathway in the pathophysiology of cortico-adrenal disease

Berthon, Annabel 15 October 2012 (has links)
Les tumeurs cortico-surrénaliennes bénignes et malignes sont associées à une morbidité élevée résultant de l’hypersécrétion des hormones cortico-surrénaliennes, retrouvée chez près de 60% des patients. Au delà des perturbations endocrines, les carcinomes cortico-surrénaliens (CCS) sont des tumeurs de mauvais pronostic avec 16 à 38% de survie à 5 ans. Cette agressivité résulte à la fois de la présence de métastases chez de nombreux patients, au moment du diagnostic (30 à 40% des cas) et de l’absence d’approches thérapeutiques, au delà de la résection chirurgicale de la tumeur primaire. Au début de ma thèse, les mécanismes moléculaires impliqués dans le développement des tumeurs bénignes et malignes de la cortico-surrénale, étaient largement méconnus. L’activation anormale de la voie de signalisation Wnt/ßcaténine dans 48% des tumeurs bénignes et 37% des tumeurs malignes, suggérait que cette voie pouvait, comme dans d’autres tissus, participer au développement tumoral dans la cortico-surrénale. Afin de confirmer cette hypothèse, nous avons développé et caractérisé un modèle de souris transgéniques dans lesquelles la ßcaténine est constitutivement activée, spécifiquement dans le cortex surrénalien (souris ∆Cat). Grâce à ces souris, nous avons démontré pour la première fois que la ßcaténine agit comme un oncogène dans la cortico-surrénale, mais que son activation constitutive ne suffit pas à déclencher systématiquement le développement de tumeurs malignes. Chez plus de 90% des patients, la formation des CCS est associée à la surexpression du facteur de croissance IGF2. Grâce à des modèles de souris transgéniques qui surexpriment Igf2, nous avons pu montrer que cette surexpression n’a que peu d’effet sur l’initiation ou la progression tumorale, suggérant que d’autres altérations sont requises pour favoriser la transition maligne. Des résultats préliminaires encourageants suggèrent que la surexpression de l’histone méthyl-transférase EZH2 et les altérations épigénétiques résultantes, pourraient être la clé du développement des CCS. Parallèlement, nous avons montré que l’activation constitutive de la ßcaténine conduit au développement d’un hyperaldostéronisme primaire chez les souris ∆Cat, suggérant que l’activation de la voie Wnt/ßcaténine pourrait participer à la formation d’adénomes surrénaliens producteurs d’aldostérone (APA) chez les patients. Effectivement, nous avons mis en évidence que l’activation constitutive de la ßcaténine est l’altération moléculaire la plus fréquente dans les APA, avec une prévalence de 68%. Des analyses in vitro m’ont permis de montrer que la ßcaténine stimule la production d’aldostérone en contrôlant directement et indirectement l’expression de deux enzymes clés de la synthèse d’aldostérone – CYP21 et CYP11B2 – et du récepteur à l’angiotensine II (le sécrétagogue naturel de l’aldostérone), AT1R. Nous avons par ailleurs montré que la production excessive d’aldostérone chez les souris ∆Cat, pouvait être maîtrisée par un régime enrichi en quercétine, un inhibiteur naturel de l’activité transcriptionnelle de la ßcaténine. L’ensemble de ces résultats démontre l’importance de la voie Wnt/ßcaténine dans la tumorigenèse surrénalienne et dans l’hypersécrétion d’aldostérone ce qui fait d’elle une nouvelle cible thérapeutique potentielle. / Benign and malignant adrenocortical tumours are associated with a high morbidity caused by the hypersecretion of adrenocortical hormones found in approximately 60% of patients. Moreover, adrenocortical carcinomas (ACC) have poor prognosis with a 5 years survival rate of 16 to 38%. This aggressiveness results from both the presence of metastases at diagnosis in most patients (30 to 40% of cases) and the absence of therapeutic approaches apart from surgical resection of primary tumours. At the start of my thesis, the molecular mechanisms involved in the development of benign and malignant adrenocortical tumours were largely unknown. Abnormal activation of the Wnt/ßcatenin pathway found in 48% of benign tumours and 37% of malignant tumours suggests that as in other tissues, this pathway could participate in tumour development in the adrenal cortex. To confirm this hypothesis, we developed and characterized a transgenic mouse model with constitutive activation of ßcatenin, specifically in the adrenal cortex (∆Cat mice). With this model, we demonstrated for the first time that ßcatenin acted as an adrenocortical oncogene but that this activation was insufficient to systematically induce the development of adrenocortical carcinomas. In almost 90% of patients, CCS formation is associated with the overexpression of the growth factor IGF2. However, the development of a model of Igf2 overexpression in transgenic mice, allowed us to demonstrate that this overexpression could not initiate tumour formation and that it had a mild effect on tumour progression. This suggested that other alterations were necessary for malignant progression. Our encouraging preliminary results suggest that upregulation of the histone methyltransferase EZH2 and the resulting epigenetic defects could be the cause of ACC development. In parallel, we demonstrated that constitutive ßcatenin activation induced primary hyperaldosteronism development in ∆Cat mice suggesting that aberrant activation of the Wnt pathway could be involved in formation of aldosterone-producing adenomas (APA) in patients. Indeed, we showed that constitutive activation of ßcatenin was the most frequent molecular alteration in APA with a prevalence of 68%. In vitro analysis allowed us to demonstrate that ßcatenin stimulates aldosterone production by controlling directly and indirectly the expression of two key enzymes of aldosterone synthesis –CYP21 and CYP11B2- and of the angiotensin II receptor, AT1R. Furthermore, we showed that excessive aldosterone production in ∆Cat mice could be controlled by a diet enriched in quercetin, a natural inhibitor of the transcriptional activity of ßcatenin. Altogether these results demonstrate the essential role of the Wnt/ßcatenin pathway in adrenocortical tumorigenesis and aldosterone secretion. Consequently, this pathway could be a new potential therapeutic target for the treatment of most adrenal tumours.

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