Diagnosis and management of children and adult craniopharyngiomas: a French Endocrine Society/French Society for Paediatric Endocrinology & Diabetes Consensus Statement.

Craniopharyngiomas are rare hypothalamic-pituitary tumors found in young children, adolescents and adults, and their multidisciplinary management required, calls for consistent practices for practicioners, patients and families. The French Endocrine Society and French Society for Pediatric Endocrinology & Diabetes enlisted and coordinated adult and paediatric endocrinologists, neurosurgeons, pathologists, radiotherapists as well as psychologists, dieticians and a patient association, to draft a reference document on this severe disease. The management of craniopharyngiomas remains complex due to their aggressive nature, invasive behavior, and propensity for recurrence, requiring a sequential and measured therapeutic approach and follow-up in expert centers. Although patient survival rates are high, the consequences of both the tumor and its treatment can lead to serious comorbidities and impaired quality of life, particularly in those patients with lesional hypothalamic syndrome. Recent advances have allowed the two described tumor types - papillary and adamantinomatous - to be associated with distinct molecular signatures, specific pathophysiological mechanisms and ipso facto, distinct therapeutic approaches, including innovative medications for hyperphagia, that will continue to evolve. This consensus statement covers all stages in the management of patients with craniopharyngioma, from diagnosis to therapeutic strategies including the long-term follow-up.

Gonadotropic status in adult women with pituitary stalk interruption syndrome.

OBJECTIVE: Pituitary stalk interruption syndrome (PSIS) is a rare cause of congenital hypopituitarism. Limited data exist on the gonadotropic status and fertility of adult women with PSIS. Our study aims to describe pubertal development and the evolution of gonadotropic function and fertility in adult women with PSIS. DESIGN: A retrospective multicentric French study. METHODS: We described gonadotropic function in 56 adult women with PSIS from puberty onward. We compared live birth rates per woman with PSIS with age-matched controls from the large French epidemiological cohort (CONSTANCES). Additionally, we assessed height, body mass index (BMI), blood pressure, other metabolic parameters, and socioeconomic status. RESULTS AND CONCLUSIONS: Among 56 women with PSIS, 36 did not experience spontaneous puberty. Of these, 13 underwent ovarian stimulation, resulting in 7 women having a total of 11 children. In the subgroup with spontaneous puberty (n = 20), 4 had a total of 8 pregnancies, while 6 developed secondary gonadotropic deficiency. Women with PSIS had fewer children than controls (0.33 vs 0.63, P = .04). Median height was also lower (160.5 vs 165.0 cm, P < .0001). Although mean blood pressure was lower in women with PSIS compared with controls (111.3/65.9 ± 11.2/8.1 vs 118.7/72.1 ± 10.1/7.7 mmHg, P < .001), there were no significant differences in other metabolic parameters, notably BMI and lipid profile. Employment/academic status was not different in the 2 groups, but fewer women with PSIS were in relationships (42% vs 57.6% in controls, P = .02). The fertility prognosis in patients with PSIS needs optimization. Patients should be informed about the likelihood of declining gonadotropic function over time.

Position statement on the diagnosis and management of congenital pituitary deficiency in adults: The French National Diagnosis and Treatment Protocol (NDTP).

Pituitary deficiency, or hypopituitarism, is a rare chronic disease. It is defined by insufficient synthesis of one or more pituitary hormones (growth hormone, TSH, ACTH, LH-FSH, prolactin), whether or not associated with arginine vasopressin deficiency (formerly known as diabetes insipidus). In adult patients, it is usually acquired (notably during childhood), but can also be congenital, due to abnormal pituitary development. The present study focuses on congenital pituitary deficiency in adults, from diagnosis to follow-up, including special situations such as pregnancy or the elderly. The clinical presentation is highly variable, ranging from isolated deficit to multiple deficits, which may be part of a syndromic form or not. Diagnosis is based on a combination of clinical, biological (assessment of all hormonal axes), radiological (brain and hypothalamic-pituitary MRI) and genetic factors. Treatment consists in hormonal replacement therapy, adapted according to the period of life and the deficits, which may be progressive. Comorbidities, risk of complications and acute decompensation, and the impact on fertility and quality of life all require adaptative multidisciplinary care and long-term monitoring.

Evaluating the satisfaction and utility of social networks in medical practice and continuing medical education.

BACKGROUND: Digital health has surged during the Covid health crisis, and the use of social media, already prevalent in medicine, has significantly increased. There are Social Networks groups dedicated to physicians with an educational purpose. These groups also facilitate peer discussions on medical questions and the sharing of training materials. OBJECTIVES: The aim of our study was to assess the value of these new tools and their contribution to medical education. METHODS: An anonymous questionnaire was conducted among members of a Social Networks community group for physicians. The survey received responses from 1451 participants. RESULTS: The majority of participants believed they had enriched their medical knowledge and accessed documents they would not have accessed without the group. Subgroup analysis showed that the contribution of this tool is more pronounced for general practitioners and doctors practicing in limited healthcare access. CONCLUSION: It is essential to develop digital tools that enhance physician training, and social networks represent a valuable educational tool.

Position statement on the diagnosis and management of acromegaly: The French National Diagnosis and Treatment Protocol (NDTP).

Acromegaly is a rare disease with prevalence of approximately 60 cases per million, slight female predominance and peak onset in adults in the fourth decade. Clinical diagnosis is often delayed by several years due to the slowly progressive onset of symptoms. There are multiple clinical criteria that define acromegaly: dysmorphic syndrome of insidious onset, symptoms related to the pituitary tumor (headaches, visual disorders), general signs (sweating, carpal tunnel syndrome, joint pain, etc.), complications of the disease (musculoskeletal, cardiovascular, pneumological, dental, metabolic comorbidities, thyroid nodules, colonic polyps, etc.) or sometimes clinical signs of associated prolactin hypersecretion (erectile dysfunction in men or cycle disorder in women) or concomitant mass-induced hypopituitarism (fatigue and other symptoms related to pituitary hormone deficiencies). Biological confirmation is based initially on elevated IGF-I and lack of GH suppression on oral glucose tolerance test or an elevated mean GH on repeated measurements. In confirmed cases, imaging by pituitary MRI identifies the causal tumor, to best determine management. In a minority of cases, acromegaly can be linked to a genetic predisposition, especially when it occurs at a young age or in a familial context. The first-line treatment is most often surgical removal of the somatotroph pituitary tumor, either immediately or after transient medical treatment. Medical treatments are most often proposed in patients not controlled by surgical removal. Conformal or stereotactic radiotherapy may be discussed on a case-by-case basis, especially in case of drug inefficacy or poor tolerance. Acromegaly should be managed by a multidisciplinary team, preferably within an expert center such as a reference or skill center for rare pituitary diseases.

Prevalence of prediabetes and undiagnosed diabetes in a large urban middle-aged population: the CARVAR 92 cohort.

BACKGROUND: The aim of this study was to assess the prevalence of prediabetes and unknown diabetes and its long-term change in a large middle-aged urban population. METHODS: We conducted a screening campaign between 2007 and 2018 for cardiovascular risk factors in the western suburbs of Paris including subjects aged 40-70 (CARVAR 92). Among subjects who reported no previous diabetes, prediabetes and undiagnosed diabetes were defined as follows: fasting plasma glucose (FPG) ≥ 6.1 mmol/l (110 mg/dl) and < 7 mmol/l (126 mg/dl) for prediabetes according to WHO criteria (FPG between 5.6 and 6.9 mmol/l according to ADA criteria) and FPG ≥ 7.0 mmol/l for undiagnosed diabetes. RESULTS: Of the 32,721 subjects in the CARVAR 92 cohort, 32,675 were included in this analysis. The median age of the patients was 56 years [30, 94], 45.4% were male, 5.9% had known diabetes, 36.4% were overweight and 18.7% obese. Among patients without previously known diabetes (n = 30,759), 8.1% had prediabetes according to WHO criteria (27.2% according to ADA criteria) and 2.3% had diabetes. Subjects with prediabetes and unknown diabetes were more likely to be male, older, and overweight or obese than non-diabetic subjects. From 2007 to 2018, the prevalence of prediabetes, unknown diabetes, and known diabetes decreased, except for prediabetes which remained stable for people aged 55-64. CONCLUSION: The prevalence of prediabetes and unknown diabetes remains high but decreased during a 12-year period. About one-quarter of diabetes cases remain undiagnosed. Our results highlight that there is still a room for screening and cardiovascular prevention campaigns. TRIAL REGISTRATION: IRB00012437.

Pituitary surgery as alternative to dopamine agonists treatment for microprolactinomas: a cohort study.

OBJECTIVE: Microprolactinomas are currently treated with dopamine agonists. Outcome information on microprolactinoma patients treated by surgery is limited. This study reports the first large series of consecutive non-invasive microprolactinoma patients treated by pituitary surgery and evaluates the efficiency and safety of this treatment. DESIGN: Follow-up of a cohort of consecutive patients treated by surgery. METHODS: Between January 2008 and October 2020, 114 adult patients with pure microprolactinomas were operated on in a single tertiary expert neurosurgical department, using an endoscopic endonasal transsphenoidal approach. Eligible patients presented with a microprolactinoma with no obvious cavernous invasion on MRI. Prolactin was assayed before and after surgery. Disease-free survival was modeled using Kaplan-Meier representation. A cox regression model was used to predict remission. RESULTS: Median follow-up was 18.2 months (range: 2.8-155). In this cohort, 14/114 (12%) patients were not cured by surgery, including ten early surgical failures and four late relapses occurring 37.4 months (33-41.8) after surgery. From Kaplan-Meier estimates, 1-year and 5-year disease free survival was 90.9% (95% CI: 85.6-96.4%) and 81% (95% CI: 71.2-92.1%) respectively. The preoperative prolactinemia was the only significant preoperative predictive factor for remission (P < 0.05). No severe complication was reported, with no anterior pituitary deficiency after surgery, one diabetes insipidus, and one postoperative cerebrospinal fluid leakage properly treated by muscle plasty. CONCLUSIONS: In well-selected microprolactinoma patients, pituitary surgery performed by an expert neurosurgical team is a valid first-line alternative treatment to dopamine agonists.

Structural analysis of the impact of a novel androgen receptor gene mutation in two adult patients with mild androgen insensitivity syndrome.

Androgen receptor gene (AR) mutations are responsible for androgen insensitivity syndrome (AIS) presenting with a clinical phenotype that ranges from gynaecomastia and/ or infertility in mild AIS (MAIS) to complete testicular feminisation in complete AIS. We report a novel AR gene mutation in two unrelated adult patients with MAIS and we studied its functional impact using 3D modelling. Patient 1, referred for infertility, presented with gynaecomastia, mild hypospadias and bilateral testicular hypotrophy contrasting with high testosterone levels, an elevated FSH, an elevated androgen sensitivity index (ASI) and oligoasthenoteratospermia. In vitro fertilisation and intracytoplasmic sperm injection resulted in a successful twin pregnancy. Patient 2 referred for a decrease in athletic performance had surgically treated gynaecomastia, oligoasthenospermia, high testosterone levels and an elevated ASI. Despite his impaired spermogram, he fathered two children without assisted reproductive technology. AR gene sequencing in the two patients revealed a common novel missense mutation, Ala699Thr, in exon 4 within the ligand-binding domain. 3D modelling studies showed that this mutation may impact dimer stability upon ligand binding or may affect allosteric changes upon dimerisation. This study illustrates the value of structural analysis for the functional study of mutations and expands the database of AR gene mutations.

Coexistence of Autoimmune Hyper- and Hypothyroidism in a Kindred with Reduced Sensitivity to Thyroid Hormone.

INTRODUCTION: Resistance to thyroid hormone beta (RTHß) is a rare disease with an autosomal dominant transmission. Diagnosis may be challenging especially in patients with hyper- or hypothyroidism. CASE PRESENTATION: A 31-year-old male patient with suppressed thyroid-stimulating hormone (TSH), elevated free thyroxine and free triiodothyronine, along with high thyroid receptor antibodies was diagnosed with Graves' disease. Benzylthiouracil was started. One month later, reduced sensitivity to thyroid hormones was suspected because of persistently high thyroid hormone levels contrasting with high TSH level. Molecular analysis highlighted a 10c.1357C>T p.P453S mutation in the thyroid hormone receptor beta gene (THRB). RTHß was diagnosed. Several relatives also had RTHß (the mother, the young son, and 2 out of 3 siblings). Autoimmune hypothyroidism was present in the mother, whereas 2 out of 3 siblings had asymptomatic autoimmunity. DISCUSSION/CONCLUSION: Both Graves' disease and autoimmune hypothyroidism were described in patients with RTHß. We show here for the first time that autoimmune hypo- and hyperthyroidism may coexist in kindred with RTHß. Seven previously published cases of Graves' disease and RTHß were retrieved and analyzed. Treatments and thyroid hormone level targets are discussed as well as the possible link between RTHß and autoimmune thyroid diseases.

Foetal exposure to mitotane/Op'DDD: Post-natal study of four children.

OBJECTIVE: Mitotane/Op'DDD is used in the treatment of adrenocortical carcinoma and for other causes of hypercortisolism. Mitotane inhibits cortisol secretion and displays adrenolytic and antitumor actions. This compound is a metabolite of the pesticide and endocrine disruptor DDT (dichlorodiphenyltrichloroethane) and is classified among teratogenic compounds worldwide. However, little is known about its effects on human development. DESIGN: The outcome of four children exposed to mitotane during their intrauterine life was examined. PATIENTS: Patients having conceived while taking mitotane, or with detectable mitotane plasma levels, were retrospectively recruited via the French COMETE and FIRENDO networks. MEASUREMENTS: Mitotane in maternal plasma, adrenocortical hormones in children. RESULTS: Three women treated with mitotane gave birth to four children. During early pregnancy, all patients had detectable mitotane plasma levels (0.9, 2.4 and 6.7 mg/L, respectively). During pregnancy, no foetal malformations were detected. The four exposed newborns presented at birth with apparently normal adrenal function and genitalia. One twin female had a low birthweight. Evaluation at birth and after 3 months, 2 years and 7 years of follow-up showed no significant neurological abnormality. Evaluation of adrenocortical functions showed no cortisol deficiency. CONCLUSIONS: Unexpectedly, exposure of these four children to mitotane during foetal life seemed to have no clear teratogenic effect. However, considering the sub-therapeutic mitotane concentrations used here, the small number of cases, and because long-term follow-up is unknown, we strongly advise not to take mitotane during pregnancy and still recommend avoiding pregnancy, at least as long as mitotane plasma levels remain detectable.

[Adrenocortical carcinoma and pregnancy]. / Corticosurrénalome et grossesse.

Adrenocortical carcinoma is a rare cancer with a poor but heterogeneous prognosis. These tumours are more frequently encountered in women, sometimes very young and may be diagnosed in women in their child bearing years or already pregnant. Several clinical data have indicated that the secretion and or proliferation of adrenocortical tumors may be affected by the hormonal context of pregnancy. In this review, we will examine the link between ACC and pregnancy in two main aspects. We will first consider the situation of a pregnant woman with a clinical suspicion of adrenocortical carcinoma: which diagnostic procedures will be useful and safe for the foetus? What are the therapeutic options? What is the prognosis if the diagnosis is confirmed? In a second part, we will examine the possible risk of mothering a child in a patient previously treated for an ACC. The data shown here were obtained from studies carried out in a tertiary reference medical centre in Paris (Hôpital Cochin) and from the European Network for the Study of Adrenal Tumor (ENS@T) database of adrenocortical carcinoma.

Very low frequency of germline GPR101 genetic variation and no biallelic defects with AIP in a large cohort of patients with sporadic pituitary adenomas.

CONTEXT: Recently, germline and somatic GPR101 p.(E308D) mutation was found in patients with isolated acromegaly. It is not known whether GPR101 point mutations are associated with other histological types of pituitary adenoma. OBJECTIVE: We sought germline GPR101 mutations in patients with sporadic pituitary adenomas, and compared the phenotypes of GPR101 mutation carriers and AIP mutation carriers. DESIGN: An observational cohort study performed between 2007 and 2014 in a single referral center. PARTICIPANTS: This prospective study involved 766 unselected patients (413 women) with sporadic pituitary adenomas of all histotypes. METHODS: Entire GPR101 and AIP coding sequence were screened for germline mutations. RESULTS: Twelve patients (1.6%) were found to carry the GPR101 p.(E308D) mutation or rare GPR101 variants. The minor allele frequency of the GPR101 mutation and variants was higher in patients with pituitary adenomas than in unaffected individuals included in the Exome Aggregation Consortium database. Three of the six patients with the GPR101 p.(E308D) mutation had adult-onset acromegaly, two had adrenocorticotropin-secreting adenomas, and one had a nonfunctioning macroadenoma. Six patients carried rare GPR101 variants. Germline AIP mutations or rare AIP variants were identified in 32 patients (4.2%). AIP mutation carriers were younger at diagnosis than GPR101 mutation carriers and non carriers. None of the patients harbored mutations in both the GPR101 and AIP genes. CONCLUSION: Germline GPR101 mutations are very rare in patients with sporadic pituitary adenomas of various histotypes. No digenism with AIP was identified. Further studies are required to establish whether and how genetic variation in GPR101 gene contributes to pituitary tumorigenesis.

Pregnancy in Women Previously Treated for an Adrenocortical Carcinoma.

CONTEXT: Adrenocortical carcinomas (ACCs) are rare, aggressive tumors, of which some express receptors for estradiol, progesterone, and/or human chorionic gonadotoropin. Because this disease is encountered frequently in young women, pregnancy is a relevant issue. OBJECTIVE: to evaluate the impact of pregnancy on outcome of patients previously treated for ACC. DESIGN/SETTING: retrospective observational multicenter study of the European Network for the Study of Adrenal Tumors. PATIENTS: Seventeen ACC patients (21 pregnancies), becoming pregnant at least 3 months after the initial treatment, were compared with 247 nonpregnant ACC patients less than 47 years old. A control group of 34 patients matched for age, sex, and tumor stage was used for survival analysis. MAIN OUTCOME MEASURE(S): Overall survival, tumors characteristics at diagnosis, pregnancy outcome. RESULTS: All 17 patients with pregnancies had localized ACC. The median time between surgery and conception was 4 years (0.3-12 y). Two pregnancies were terminated at 8 weeks. Sixteen women gave birth to 19 live infants. With exception of 1 (presumably unrelated) cardiac malformation, no severe fetal or maternal complication was observed. After a median follow-up time of 8.36 years and 5.26 years after the first conception, 1 of the 17 patients had died and 5 had experienced a recurrence, among whom 3 occurred before conception. Overall survival was not significantly different between the "pregnancy group" and the matched controls. CONCLUSION: Pregnancy in patients previously treated for ACC seems to not be associated with worse clinical outcome, although a "healthy mother effect" cannot be excluded.

Hormonal, Radiological, NP-59 Scintigraphy, and Pathological Correlations in Patients With Cushing's Syndrome Due to Primary Pigmented Nodular Adrenocortical Disease (PPNAD).

CONTEXT: Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of ACTH-independent Cushing's syndrome that may occur in an isolated form or as part of Carney complex. The diagnosis of this disease can be difficult preoperatively because computed tomography (CT) scan can be normal or suggest unilateral adrenal lesion, which can impede the correct diagnosis of bilateral adrenal disease. OBJECTIVE: The aim of our study was to describe the results of preoperative imaging (adrenal [6ß-(131)I]iodomethyl-19-norcholesterol] [NP-59] scintigraphy and standard adrenal CT scan) and their correlations with clinical, pathological, and genetics investigations in patients with PPNAD. PATIENTS AND METHODS: Seventeen patients with ACTH-independent syndrome due to PPNAD were investigated with a standard adrenal CT scan and NP-59 scintigraphy. Hormonal, pathological, and genetics data were analyzed. RESULTS: Four males and 13 females (median age, 27 y) were included. PPNAD was isolated in 11 patients (with PRKAR1A mutation, n = 7; and without PRKAR1A mutation, n = 4) and was associated with extra-adrenal manifestations of Carney complex in six patients (with PRKAR1A mutation, n = 4; and without PRKAR1A mutation, n = 2). Standard adrenal CT scan revealed micronodules in 11 patients, macronodules in three patients, and was normal in three patients. All patients demonstrated bilateral adrenal radiocholesterol uptake. Adrenal uptake was asymmetrical in 10 of 17 patients (59%). Asymmetrical uptake correlated with the presence of macronodules at pathological analysis (P = .03). CONCLUSION: Standard adrenal CT scan most often reveals micronodules but there is no specific CT imaging. NP-59 scintigraphy always shows a bilateral adrenal uptake confirming the bilateral nature of the disease, but asymmetrical scintigraphic uptake can be observed in patients with macronodules.

Management of nonfunctioning pituitary incidentaloma.

Prevalence of pituitary incidentaloma is variable: between 1.4% and 27% at autopsy, and between 3.7% and 37% on imaging. Pituitary microincidentalomas (serendipitously discovered adenoma <1cm in diameter) may increase in size, but only 5% exceed 10mm. Pituitary macroincidentalomas (serendipitously discovered adenoma>1cm in diameter) show increased size in 20-24% and 34-40% of cases at respectively 4 and 8years' follow-up. Radiologic differential diagnosis requires MRI centered on the pituitary gland. Initial assessment of nonfunctioning (NF) microincidentaloma is firstly clinical, the endocrinologist looking for signs of hypersecretion (signs of hyperprolactinemia, acromegaly or Cushing's syndrome), followed up by systematic prolactin and IGF-1 assay. Initial assessment of NF macroincidentaloma is clinical, the endocrinologist looking for signs of hormonal hypersecretion or hypopituitarism, followed up by hormonal assay to screen for hypersecretion or hormonal deficiency and by ophthalmologic assessment (visual acuity and visual field) if and only if the lesion is near the optic chiasm (OC). NF microincidentaloma of less than 5mm requires no surveillance; those of≥5mm are not operated on but rather monitored on MRI at 6months and then 2years. Macroincidentaloma remote from the OC is monitored on MRI at 1year, with hormonal exploration (for anterior pituitary deficiency), then every 2years. When macroincidentaloma located near the OC is managed by surveillance rather than surgery, MRI is recommended at 6months, with hormonal and visual exploration, then annual MRI and hormonal and visual assessment every 6months. Surgery is indicated in the following cases: evolutive NF microincidentaloma, NF macroincidentaloma associated with hypopituitarism or showing progression, incidentaloma compressing the OC, possible malignancy, non-compliant patient, pregnancy desired in the short-term, or context at risk of apoplexy.

Silent, but not unseen: multimicrocystic aspect on T2-weighted MRI in silent corticotroph adenomas.

OBJECTIVE: Silent corticotroph adenomas (SCAs) present as nonfunctional pituitary tumours in routine pre-operative evaluation. The objective of this study was to evaluate the diagnostic accuracy of MRI T2-weighted sequences for detecting the corticotroph subtype pre-operatively. DESIGN: The pre-operative T2-weighted MRI sequences were retrospectively evaluated in patients with SCA and two control groups: clinically manifest corticotroph macroadenomas (CSMs) and nonfunctional gonadotroph macroadenomas (NFGMs). All were selected from a registry of 1096 patients in whom transsphenoidal surgery was performed in the same tertiary reference centre. T2-weighted MRI sequences were independently classified by one senior endocrinologist and one senior radiologist who were blinded to the clinical and histological features. PATIENTS: Seventeen patients with SCA, 14 with CSM and 60 with NFGM were included in this study. MEASUREMENTS: Pituitary MRI with T2-weighted sequences. Two aspects were retained: multiple microcysts (MMs) and the absence of microcysts. Hormonal data included plasma prolactin, IGF-1, testosterone or oestradiol, LH, FT4, TSH, morning plasma cortisol and an ACTH-stimulation test, when available. RESULTS: Multiple microcysts were present in 76% (13/17) of SCAs, 21% (3/14) of CSMs and 5% (3/60) of NFGMs. The presence of MMs in clinically nonfunctioning macroadenomas had a sensitivity of 76% and a specificity of 95% for predicting SCA. CONCLUSION: The presence of MMs in T2-weighted MRI is a good diagnostic tool to suggest the corticotroph subtype in an apparently nonfunctional pituitary tumour.

Inactivation of the Carney complex gene 1 (PRKAR1A) alters spatiotemporal regulation of cAMP and cAMP-dependent protein kinase: a study using genetically encoded FRET-based reporters.

Carney complex (CNC) is a hereditary disease associating cardiac myxoma, spotty skin pigmentation and endocrine overactivity. CNC is caused by inactivating mutations in the PRKAR1A gene encoding PKA type I alpha regulatory subunit (RIα). Although PKA activity is enhanced in CNC, the mechanisms linking PKA dysregulation to endocrine tumorigenesis are poorly understood. In this study, we used Förster resonance energy transfer (FRET)-based sensors for cAMP and PKA activity to define the role of RIα in the spatiotemporal organization of the cAMP/PKA pathway. RIα knockdown in HEK293 cells increased basal as well as forskolin or prostaglandin E1 (PGE1)-stimulated total cellular PKA activity as reported by western blots of endogenous PKA targets and the FRET-based global PKA activity reporter, AKAR3. Using variants of AKAR3 targeted to subcellular compartments, we identified similar increases in the response to PGE1 in the cytoplasm and at the outer mitochondrial membrane. In contrast, at the plasma membrane, the response to PGE1 was decreased along with an increase in basal FRET ratio. These results were confirmed by western blot analysis of basal and PGE1-induced phosphorylation of membrane-associated vasodilator-stimulated phosphoprotein. Similar differences were observed between the cytoplasm and the plasma membrane in human adrenal cells carrying a RIα inactivating mutation. RIα inactivation also increased cAMP in the cytoplasm, at the outer mitochondrial membrane and at the plasma membrane, as reported by targeted versions of the cAMP indicator Epac1-camps. These results show that RIα inactivation leads to multiple, compartment-specific alterations of the cAMP/PKA pathway revealing new aspects of signaling dysregulation in tumorigenesis.

Germline AIP mutations in apparently sporadic pituitary adenomas: prevalence in a prospective single-center cohort of 443 patients.

CONTEXT: Germline mutations of the AIP (aryl-hydrocarbon receptor interacting protein) gene are associated with a predisposition to pituitary adenomas. Such mutations are found in about half of patients with familial acromegaly, but penetrance is incomplete. OBJECTIVE: We studied the prevalence of germline AIP mutations in a large cohort of patients with apparently sporadic pituitary adenomas. PATIENTS AND SETTING: A total of 443 patients with pituitary adenomas of all histotypes, who had no familial history of pituitary adenomas or multiple endocrine neoplasia and who were examined at Bicêtre University Hospital, a tertiary referral center, between 2007 and 2010, were enrolled in this prospective study. METHODS: The entire coding sequence of the AIP gene was screened for germline mutations. A subgroup of patients were screened for large deletions or duplications of the AIP and MEN1 genes by multiplex ligation-dependent probe amplification. RESULTS: AIP mutations were detected in 16 (3.6%) of the 443 patients, comprising six of 148 patients with acromegaly (4.1%), six of 132 patients with prolactinomas (4.5%), one of 113 patients with nonfunctioning adenomas (0.9%), three of 44 patients with corticotropic adenomas (6.8%), and none of the six patients with thyrotropic adenomas. This is the first report of an AIP mutation leading to a truncated protein in a patient with Cushing's disease. Patients with AIP mutation were younger at diagnosis (24.1 vs. 42.8 yr) and had predominantly macroadenoma (12 of 16). No mutations were found in patients diagnosed after age 40 yr, whereas the prevalence before this age was 7.2% (16 of 222). Studies of seven of the AIP-mutated patients' families showed that one asymptomatic parent carried the same mutation in each case. CONCLUSION: This large prospective cohort study confirms the very low prevalence of germline AIP mutations in patients with apparently sporadic pituitary adenomas. We propose to limit AIP testing to patients diagnosed before age 40 yr with apparently sporadic large pituitary adenomas, especially GH- or PRL-secreting adenomas.