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The high expression level of somatostatin receptor 2 (SST2) in growth hormone (GH)-secreting tumors represents the rationale for the clinical use of somatostatin analogs (SSAs) in acromegaly. However, about one third of patients displays resistance to SSAs and, to date, the underlying molecular mechanisms are still under investigation. Recently, the cytoskeletal protein Filamin A (FLNA) and the scaffolding proteins β-arrestins have emerged as key modulators of the responsiveness of GH-secreting pituitary tumors to SSAs, by regulating SST2 signaling and desensitization, respectively. The aim of this study was to further explore FLNA involvement in SST2 intracellular trafficking in somatotrope cells, since alterations in this system might affect the amount of available receptor at the plasma membrane and lead to unresponsive tumor features.By biotinylation assay we first found that FLNA silencing strongly reduced octreotide-mediated SST2 internalization in rat GH3 cell line (26.9±2.7% vs 4±1.7% SST2 internalization, control vs FLNA siRNA cells, respectively, P

Natural course of prolactinomas after menopause is not fully elucidated. The aim of this study was to compare recurrence rate after cabergoline withdrawal in premenopausal vs. postmenopausal women with microprolactinoma. Sixty-two women with microprolactinoma treated with cabergoline for at least 1 year and followed for 2 years after drug withdrawal were retrospectively selected. Patients were divided into two groups: 48 patients stopped cabergoline before menopause (“PRE” group), while 14 after menopause (“POST” group). Recurrence was defined by prolactin levels above normal, confirmed on two occasions. Overall, 39/62 women relapsed. Patients who relapsed apparently had higher prolactin before withdrawal (median 216.2, range 21.2–464.3 mIU/L) compared with those in long-term remission (94.3, 29.7–402.8 mIU/L; p

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor that originates from parafollicular thyroid C cells and accounts for 5% of thyroid cancers. In inherited cases of MTC, and in about 40% of sporadic cases, activating mutations of the receptor tyrosine kinase proto-oncogene RET are found. Constitutively active RET triggers signaling pathways involved in cell proliferation, survival and motility, but the mechanisms underlying malignant transformation of C-cells have been only partially elucidated. Cofilin is a key regulator of actin cytoskeleton dynamics. A crucial role of cofilin in tumor development, progression, invasion and metastasis has been demonstrated in different human cancers, but no data are available in MTC. Interestingly, RET activation upregulates cofilin gene expression. The aim of this study was to investigate cofilin contribution in invasiveness and growth of MTC cells, and its relevance in the context of mutant RET signaling. We found that cofilin transfection in human MTC cell line TT significantly increased migration (178 ± 44%, p 0.001), invasion (165 ± 28%, p 0.01) and proliferation (146 ± 18%, p 0.001), accompanied by an increase of ERK1/2 phosphorylation (2.23-fold) and cyclin D1 levels (1.43-fold). Accordingly, all these responses were significantly reduced after genetic silencing of cofilin (-55 ± 10% migration, p 0.001, -41 ± 8% invasion, p 0.001, -17 ± 3% proliferation, p 0.001). These results have been confirmed in primary cells cultures obtained from human MTCs. The inhibition of constitutively active RET in TT cells by both the RET pharmacological inhibitor RPI-1 and the transfection of dominant negative RET mutant (RETΔTK) resulted in a reduction of cofilin expression (-37 ± 8%, p 0.001 and -31 ± 16%, p 0.01, respectively). Furthermore, RPI-1 inhibitory effects on TT cell migration (-57 ± 13%, p 0.01), but not on cell proliferation, were completely abolished in cells transfected with cofilin. In conclusion, these data indicate that an unbalanced cofilin expression, induced by oncogenic RET, contributes to promote MTC invasiveness and growth, suggesting the possibility of targeting cofilin pathway for more effective treatment of MTC.

Metabolic disorders caused by impairments of the Gsα/cAMP/PKA pathway affecting the signaling of PTH/PTHrP lead to features caused by non-responsiveness of target organs, in turn leading to manifestations similar to the deficiency of the hormone itself. Pseudohypoparathyroidism (PHP) and related disorders derive from a defect of the α subunit of the stimulatory G protein (Gsα) or of downstream effectors of the same pathway, such as the PKA regulatory subunit 1A and the phosphodiesterase type 4D. The increasing knowledge on these diseases made the actual classification of PHP outdated as it does not include related conditions such as acrodysostosis (ACRDYS) or progressive osseous heteroplasia (POH), so that a new nomenclature and classification has been recently proposed grouping these disorders under the term "inactivating PTH/PTHrP signaling disorder" (iPPSD). This review will focus on the pathophysiology, clinical and molecular aspects of these rare, heterogeneous but closely related diseases.

Pseudohypoparathyroidism (PHP), pseudo-PHP, acrodysostosis, and progressive osseous heteroplasia are heterogeneous disorders characterized by physical findings, differently associated in each subtype, including short bones, short stature, a stocky build, ectopic ossifications (features associated with Albright's hereditary osteodystrophy), as well as laboratory abnormalities consistent with hormone resistance, such as hypocalcemia, hyperphosphatemia, and elevated parathyroid hormone (PTH) and thyroid-stimulating hormone levels. All these disorders are caused by impairments in the cAMP-mediated signal transduction pathway and, in particular, in the PTH/PTHrP signaling pathway: the main subtypes of PHP and related disorders are caused by de novo or autosomal dominantly inherited inactivating genetic mutations, and/or epigenetic, sporadic, or genetic-based alterations within or upstream of GNAS, PRKAR1A, PDE4D, and PDE3A. Here we will review the impressive progress that has been made over the past 30 years on the pathophysiology of these diseases and will describe the recently proposed novel nomenclature and classification. The new term "inactivating PTH/PTHrP signaling disorder," iPPSD: (1) defines the common mechanism responsible for all diseases, (2) does not require a confirmed genetic defect, (3) avoids ambiguous terms like "pseudo," and (4) eliminates the clinical or molecular overlap between diseases.

Pasireotide has been associated with tumor shrinkage in patients with Cushing's disease subjected to long term treatment. However, to date the implicated molecular mechanisms are poorly elucidated. Here, we tested pasireotide-mediated cytostatic and cytotoxic effects in ACTH-secreting primary tumor cultures and murine corticotroph tumor cell line, AtT-20 cells. We found somatostatin receptor type 5 (SST5) expressed in 17 different ACTH-secreting tumors and SST2 detectable in 15 out of the 17 tissues. Pasireotide caused a slight but significant in vitro inhibition of cell growth in 3 out of 6 ACTH-secreting primary cultures (-12.1 ± 4.3%, P 0.01 at 10 nM), remarkably reduced phospho-ERK1/2 levels in 5 out of 8 samples (-36.4 ± 20.5%, P 0.01 at 1 μM) and triggered an increase of caspase 3/7 activity in 2 of 4 tumors (17 ± 3.6%, P 0.05 at 1 μM). Accordingly, in AtT-20 cells, pasireotide significantly inhibited cell proliferation (-10.5 ± 7.7% at 10 nM, P 0.05; -13.9 ± 10.9% at 100 nM, P 0.05; -26.8 ± 8.9% at 1 μM, P 0.01). Similar antiproliferative actions were exerted by BIM23206 and BIM23120 (SST52 selective ligands, respectively), whereas octreotide was effective when used at 1 μM (-13.3 ± 9.1%, P 0.05). Moreover, a reduction of phospho-ERK1/2 was observed upon pasireotide and BIM23206 treatment (-8.4 ± 28.6%, P 0.01 and -51.4 ± 15.9%, P 0.001 at 10 nM, respectively) but not after octreotide and BIM23120 incubation. Finally, pasireotide was able to induce cell apoptosis in AtT-20 cells at lower concentration than octreotide. Altogether these data indicate a downstream implication of SST5-mediated phospho-ERK1/2 inhibition by pasireotide resulting in ACTH-secreting tumor cells proliferation reduction. Moreover, we describe for the first time a pro-apoptotic effect of pasireotide in corticotrophs.

Background The term pseudohypoparathyroidism (PHP) describes disorders derived from resistance to the parathyroid hormone. Albright hereditary osteodystrophy (AHO) is a disorder with several physical features that can occur alone or in association with PHP. The subtype 1B, classically associated with resistance to PTH and TSH, derives from the epigenetic dysregulation of the GNAS locus. Patients showing features of AHO were described, but no explanation for such phenotypic heterogeneity is available. An AHO-like phenotype was associated with the loss of genetic information stored in chromosome 2q37, making this genomic region an interesting object of study as it could contain modifier genes involved in the development of AHO features in patients with GNAS imprinting defects. The present study aimed to screen a series of 65 patients affected with GNAS imprinting defects, with or without signs of AHO, for the presence of 2q37 deletions in order to find genes involved in the clinical variability. Results The molecular investigations performed on our cohort of patients with GNAS imprinting defects identified two overlapping terminal deletions of the long arm of chromosome 2. The smaller deletion was of approximately 3 Mb and contained 38 genes, one or more of which is potentially involved in the clinical presentation. Patients with the deletions were both affected by a combination of the most pathognomic AHO-like features, brachydactyly, cognitive impairment and/or behavioural defects. Our results support the hypothesis that additional genetic factors besides GNAS methylation defects are involved in the development of a complex phenotype in the subgroup of patients showing signs of AHO. Conclusions For the first time, the present work describes PHP patients with hormone resistance and AHO signs simultaneously affected by GNAS imprinting defects and 2q37 deletions. Although further studies are needed to confirm the cause of these two rare molecular alterations and to identify candidate genes, this finding provides novel interesting clues for the identification of factors involved in the still unexplained clinical variability observed in PHP1B. Electronic supplementary material The online version of this article (10.1186/s13148-018-0607-8) contains supplementary material, which is available to authorized users.

Background: In Spring 2020 the severe acute respiratory syndrome coronavirus 2 pandemic disease (Covid-19) badly affected Northern Italy. We have described for the first time the occurrence of thyrotoxicosis due to atypical subacute thyroiditis in 15% of patients hospitalised for Covid-19 pneumonia, compared with only 1% among patients hospitalised in the same wards during Spring 2019, thus before the Covid-19 pandemic. The whole group of Covid-19 patients also had median serum TSH concentrations significantly lower compared with the control group. The atypical thyroiditis induced by Covid-19 is not associated with neck pain, affects more men than women and especially those severely ill, thus coexists with non-thyroidal illness syndrome. Subacute thyroiditis is classically followed by subsequent occurrence of permanent thyroid dysfunction and autoimmunity, thus we have started a systematic follow-up program of these patients. Methods: Longitudinal follow-up study of survived Covid-19 patients without previous known history of thyroid disorders and/or medications, assessing serum thyroid function and autoantibodies, C reactive protein (CRP), full blood count (FBC) and thyroid ultrasound (US) every 3 months. Patients showing baseline (at hospitalisation for Covid-19) thyroid dysfunction and/or focal hypoechoic areas suggestive for subacute thyroiditis at US performed 3 months post-infection, also underwent thyroid 99mTc or I123uptake. Results: To date, 53 patients have been included in the follow-up study. At 3 months post-infection, all of them presented with increased median (IQR) serum TSH concentrations compared with baseline: 1.3 (0.9–2.0) mIU/L versus 0.9 (0.5–1.8) mIU/L (p=0.0001). Similarly, serum concentrations of free-thyroxine, free-triiodothyronine, CRP and FBC had normalised compared with baseline. All patients had negative autoantibodies to TSH receptor; autoantibodies to thyroglobulin and to thyroid peroxidase were positive in 6/53 (11%) and 5/53 (9%) of patients, respectively. The thyroid US showed the presence of focal hypoechoic areas of thyroiditis in 16/51 (32%) patients, with thyroid uptake normal in 6/16 (37%), focally reduced in 8/16 (50%) and diffusely reduced in 2/16 (12%). Conclusions: At 3 months after Covid-19 disease all patients had a normalised thyroid function, however imaging findings suggestive for subacute thyroiditis were still present in about one third of cases. The thyroid dysfunction induced by Covid-19 seems not mediated by autoimmunity. It is important to continue to follow these patients since they might develop thyroid dysfunction during the following months.

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine neoplasm of the parafollicular thyroid C cells. Although somatostatin receptors are expressed by MTCs, treatment with octreotide has shown poor efficacy, whereas recently pasireotide has demonstrated antiproliferative effects in persistent postoperative MTCs. Aim of this study was to test the effects of octreotide and pasireotide on MTC cells proliferation, cell cycle proteins expression, MAPK activation, apoptosis, calcitonin secretion, migration and invasion in TT cell line as well as in primary MTC cultured cells. Our results showed that both octreotide and pasireotide reduced TT cell proliferation (−35.2 ± 12.1%, p In conclusion, we demonstrated that octreotide and pasireotide inhibited cell proliferation and invasiveness in a subset of MTC, supporting their potential use in the control of tumor growth.

Non-functioning pituitary tumors (NFPTs) frequently present local invasiveness. Dopamine receptor 2 (DRD2) agonists are the only medical therapy that induces tumor shrinkage in some patients. Invasion requires cytoskeleton rearrangements that are tightly regulated by cofilin pathway, whose alterations correlate with invasion in different tumors. We investigated the effect of DR2D agonist on NFPT cells migration/invasion and the molecular mechanisms involved. We demonstrated that DRD2 agonist reduced migration (-44 ± 25%, p 0.01) and invasion (-34 ± 6%, p 0.001) and increased about 4-fold Ser3-phosphorylated inactive cofilin (P-cofilin) in NFPT cells. These effects were abolished by inhibiting ROCK, a kinase that phosphorylates cofilin. The overexpression of wild-type or phosphodeficient S3A-cofilin increased HP75 cells migration (+49 ± 6% and +57 ± 9% vs empty vector, respectively, p 0.05), while phosphomimetic mutant had no effect. Interestingly, P-cofilin levels were lower in invasive vs non-invasive tumors by both western blot (mean P-cofilin/total cofilin ratio 0.77 and 1.93, respectively, p 0.05) and immunohistochemistry (mean percentage of P-cofilin positive cells 17.6 and 45.7, respectively, p 0.05). In conclusion, we showed that the invasiveness of pituitary tumors is promoted by the activation of cofilin, which can be regulated by DRD2 and might represent a novel biomarker for pituitary tumors' invasive behavior.

In this review, we discuss the molecular mechanisms and prognostic implications of the protein kinase A (PKA) signaling pathway in human tumors, with special emphasis on the malignant thyroid. The PKA signaling pathway is differentially activated by the expression of regulatory subunits 1 (R1) and 2 (R2), whose levels change during development, differentiation, and neoplastic transformation. Following the identification of gene mutations within the PKA regulatory subunit R1A (PRKAR1A) that cause Carney complex-associated neoplasms, several investigators have studied PRKAR1A expression in sporadic thyroid tumors. The PKA regulatory subunit R2B (PRKAR2B) is highly expressed in benign, as well as in malignant differentiated and undifferentiated lesions. PRKAR1A is highly expressed in follicular adenomas and malignant lesions with a statistically significant gradient between benign and malignant tumors; however, it is not expressed in hyperplastic nodules. Although the importance of PKA in human malignancy outcomes is not completely understood, PRKAR1A expression correlates with tumor dimension in malignant lesions. Additional studies are needed to determine whether a relationship exists between PKA subunit expression and clinical outcomes, particularly in undifferentiated tumors. In conclusion, the R1A subunit might be a good molecular candidate for the targeted treatment of malignant thyroid tumors.

L’acqua rappresenta il principale costituente corporeo, per questo l’omeostasi idro-elettrolitica e una condizione imprescindibile per la vita. Il diabete insipido (centrale e nefrogeno) e la sindrome da inappropriata antidiuresi rappresentano le condizioni patologiche relative al mantenimento di questo equilibrio di piu frequente riscontro clinico. Il focus di questa rassegna e quello di indagare gli aspetti genetici di tali patologie, sia dal punto di vista ezio-patogenetico che clinico.

Pseudohypoparathyroidism exemplifies an unusual form of hormone resistance as the underlying molecular defect is a partial deficiency of the α subunit of the stimulatory G protein (Gsα), a key regulator of the cAMP signalling pathway, rather than of the parathyroid hormone (PTH) receptor itself. Despite the first description of this disorder dating back to 1942, later findings have unveiled complex epigenetic alterations in addition to classic mutations in GNAS underpining the molecular basis of the main subtypes of pseudohypoparathyroidism. Moreover, mutations in PRKAR1A and PDE4D, which encode proteins crucial for Gsα-cAMP-mediated signalling, have been found in patients with acrodysostosis. As acrodysostosis, a disease characterized by skeletal malformations and endocrine disturbances, shares clinical and molecular characteristics with pseudohypoparathyroidism, making a differential diagnosis and providing genetic counselling to patients and families is a challenge for endocrinologists. Accumulating data on the genetic and clinical aspects of this group of diseases highlight the limitation of the current classification system and prompt the need for a new definition as well as for new diagnostic and/or therapeutic algorithms. This Review discusses both the current understanding and future challenges for the clinical and molecular diagnosis, classification and treatment of pseudohypoparathyroidism.

Transsphenoidal route is now considered the gold standard for the removal of pituitary adenoma. Up to date, no clear superiority in terms of efficacy has been demonstrated between transsphenoidal microscopic and endoscopic approaches. Surgical safety may be a relevant argument in favor or against the choice of one of the two surgical approaches. In our experience, the microscope and the endoscope are both safe instruments for the resection of pituitary adenomas. Because of the lack of prospective randomized controlled trials, the choice of one of the two instruments should depend on surgeon-specific preferences and hospital assets. This article is protected by copyright. All rights reserved.

The cyclic adenosine monophosphate (cAMP) intracellular signaling pathway mediates the physiological effects of several hormones and neurotransmitters, acting by the activation of G-protein coupled receptors (GPCRs) and several downstream intracellular effectors, including the heterotrimeric stimulatory G-protein (Gs), the cAMP-dependent protein kinase A (PKA), and cAMP-specific phosphodiesterases (PDEs). Defective G-protein-mediated signaling has been associated with an increasing number of disorders, including Albright hereditary osteodistrophy (AHO) and pseudohypoparathyroidism (PHP), a heterogeneous group of rare genetic metabolic disorders resulting from molecular defects at the GNAS locus. Moreover, mutations in PRKAR1A and PDE4D genes have been recently detected in patients with acrodysostosis (ACRDYS), showing a skeletal and endocrinological phenotype partially overlapping with AHO/PHP. Despite the high detection rate of molecular defects by currently available molecular approaches, about 30% of AHO/PHP patients still lack a molecular diagnosis, hence the need to screen patients negative for GNAS epi/genetic defects also for chromosomal regions and genes associated with diseases that undergo differential diagnosis with PHP. According to the growing knowledge on Gsα-cAMP signaling-linked disorders, we investigated our series of patients (n = 81) with a clinical diagnosis of PHP/AHO but negative for GNAS anomalies for the presence of novel genetic variants at PRKAR1A and PDE4D genes. Our work allowed the detection of 8 novel missense variants affecting genes so far associated with ACRDYS in 9 patients. Our data further confirm the molecular and clinical overlap among these disorders. We present the data collected from a large series of patients and a brief review of the literature in order to compare our findings with already published data; to look for PRKAR1A/PDE4D mutation spectrum, recurrent mutations, and mutation hot spots; and to identify specific clinical features associated with ACRDYS that deserve surveillance during follow-up. © 2016 American Society for Bone and Mineral Research.

Somatostatin receptor type 2 (SST2) is the main pharmacological target of somatostatin (SS) analogues widely used in patients with pancreatic neuroendocrine tumours (P-NETs), this treatment being ineffective in a subset of patients. Since it has been demonstrated that Filamin A (FLNA) is involved in mediating GPCR expression, membrane anchoring and signalling, we investigated the role of this cytoskeleton protein in SST2 expression and signalling, angiogenesis, cell adhesion and cell migration in human P-NETs and in QGP1 cell line. We demonstrated that FLNA silencing was not able to affect SST2 expression in P-NET cells in basal conditions. Conversely, a significant reduction in SST2 expression (−43±21%, PPPPPin vitro release (−40±24%, PPP

Purpose: To present a single-center experience on pituitary tumor apoplexy and a review of literature focusing on predisposing and precipitating factors. Methods: Clinical presentation of our series of cases. Contemporary published literature is also reviewed. Results: The definition of this syndrome has not been consistent although now the majority of authors agree to definite it as an acute condition caused by hemorrhage or infarction of a pre-existing pituitary adenoma. Different predisposing and precipitating factors have been described in literature; among these antithrombotic and anticoagulant drugs, seem to play relevant roles. The clinical cases observed in our clinic confirm these data and suggest a probable association between elderly patients taking anticoagulant therapy and pituitary apoplexy adenoma. Conclusion: Pituitary tumor apoplexy remains a challenging disease in relation to difficulties in correct diagnosis and thus in appropriate treatment. Antithrombotic/anticoagulant therapy may have an important role as precipitating factor. When a pituitary disorder is known, great care should be taken in the prescription of anticoagulant therapy.

The antidiabetic drug metformin displays anticancer properties in several neoplasms. In pituitary NETs, aryl hydrocarbon receptor-interacting protein (AIP) is up-regulated by the somatostatin analog octreotide. Metformin inhibited QGP-1 cell proliferation in a dose- and time-dependent manner, at concentrations similar to those achievable in treated patients (-31 ± 12%, p 0.05 vs basal at 100 μM). Moreover, metformin decreased pancreatic neuroendocrine tumors (PAN-NETs) cell proliferation (-62 ± 15%, p 0.0001 vs basal at 10 mM), without any additive effect when combined with octreotide. Both octreotide and metformin induced AIP up-regulation. AIP silencing abolished the reduction of mTOR phosphorylation induced by metformin and octreotide. Moreover, metformin decreased HSP70, increased Zac1 and AhR expression; these effects were abolished in AIP silenced QGP-1 cells. In conclusion, metformin acts as an anticancer agent in PAN-NET cells, its activity is mediated by AIP and its interacting proteins. These findings provide a novel insight into the antitumorigenic mechanism of metformin.

Pseudohypoparathyroidism (PHP), pseudo-PHP, acrodysostosis, and progressive osseous heteroplasia are heterogeneous disorders characterized by physical findings, differently associated in each subtype, including short bones, short stature, a stocky build, ectopic ossifications (features associated with Albright's hereditary osteodystrophy), as well as laboratory abnormalities consistent with hormone resistance, such as hypocalcemia, hyperphosphatemia, and elevated parathyroid hormone (PTH) and thyroid-stimulating hormone levels. All these disorders are caused by impairments in the cAMP-mediated signal transduction pathway and, in particular, in the PTH/PTHrP signaling pathway: the main subtypes of PHP and related disorders are caused by de novo or autosomal dominantly inherited inactivating genetic mutations, and/or epigenetic, sporadic, or genetic-based alterations within or upstream of GNAS, PRKAR1A, PDE4D, and PDE3A. Here we will review the impressive progress that has been made over the past 30 years on the pathophysiology of these diseases and will describe the recently proposed novel nomenclature and classification. The new term "inactivating PTH/PTHrP signaling disorder," iPPSD: (1) defines the common mechanism responsible for all diseases, (2) does not require a confirmed genetic defect, (3) avoids ambiguous terms like "pseudo," and (4) eliminates the clinical or molecular overlap between diseases.

Background: Cushing disease (CD) represents the principal cause of endogenous hypercortisolism. The first-line therapy of CD is surgical removal of the ACTH-secreting pituitary adenoma, which is generally followed by adrenal insufficiency (AI). Objective: To analyze the recovery of AI in patients with CD after pituitary surgery in relation with recurrence and persistent remission of CD. Patients and Methods: We performed a retrospective analysis of patients with CD who met the following inclusion criteria: adult age, presence of AI 2 months after the surgical intervention, and a minimum follow-up of 3 years after the surgical intervention. Results: Sixty-one patients were followed for a median of 6 years. Ten (16.4%) patients recurred during follow-up. The patients who restored adrenal function did so after a median time of 19 months, with a significantly shorter time in the recurrence group (12.5 vs. 25 months, p = 0.008). All 10 patients who recurred recovered their adrenal function within 22 months. The recovery rate of AI in the persistent remission group was 37.3% (19/51) at 3 years and 55.8% (24/43) at 5 years. In all patients the duration of AI was negatively associated with disease recurrence. Conclusion: The duration of postsurgical AI in patients with recurrent CD is significantly shorter than that in patients with persistently remitted CD, and this parameter may be a useful predictor of recurrence. Patients showing a normal pituitary-adrenal axis within 2 years after surgery should be strictly monitored as they are at higher risk of disease relapse.

This Consensus Statement covers recommendations for the diagnosis and management of patients with pseudohypoparathyroidism (PHP) and related disorders, which comprise metabolic disorders characterized by physical findings that variably include short bones, short stature, a stocky build, early-onset obesity and ectopic ossifications, as well as endocrine defects that often include resistance to parathyroid hormone (PTH) and TSH. The presentation and severity of PHP and its related disorders vary between affected individuals with considerable clinical and molecular overlap between the different types. A specific diagnosis is often delayed owing to lack of recognition of the syndrome and associated features. The participants in this Consensus Statement agreed that the diagnosis of PHP should be based on major criteria, including resistance to PTH, ectopic ossifications, brachydactyly and early-onset obesity. The clinical and laboratory diagnosis should be confirmed by a molecular genetic analysis. Patients should be screened at diagnosis and during follow-up for specific features, such as PTH resistance, TSH resistance, growth hormone deficiency, hypogonadism, skeletal deformities, oral health, weight gain, glucose intolerance or type 2 diabetes mellitus, and hypertension, as well as subcutaneous and/or deeper ectopic ossifications and neurocognitive impairment. Overall, a coordinated and multidisciplinary approach from infancy through adulthood, including a transition programme, should help us to improve the care of patients affected by these disorders, This Consensus Statement and the series of consensus meetings were supported by funds from the European Cooperation in Science and Technology (COST) action BM1208 on imprinting disorders (www.imprinting- disorders.eu), the European Society for Paediatric Endocrinology (ESPE) and the European Society for Endocrinology (ESE). Travel costs and housing of the representatives of the Asian Pacific Paediatric Endocrine Society (APPES) and of the Pediatric Endocrine Society (PES) were supported by their societies. The authors received no funding from pharmaceutical companies

The cytoskeletal protein filamin A (FLNA) has been suggested to play an important role in the responsiveness of GH-secreting pituitary tumors to somatostatin receptor subtype 2 (SSTR2) agonists by regulating SSTR2 expression and signaling. However, the underlying mechanisms are unknown. In this study, we use fast multicolor single-molecule microscopy to image individual SSTR2 and FLNA molecules at the surface of living cells with unprecedented spatiotemporal resolution. We find that SSTR2 and FLNA undergo transient interactions, which occur preferentially along actin fibers and contribute to restraining SSTR2 diffusion. Agonist stimulation increases the localization of SSTR2 along actin fibers and, subsequently, SSTR2 clustering and recruitment to clathrin-coated pits (CCPs). Interfering with FLNA-SSTR2 binding with a dominant-negative FLNA fragment increases SSTR2 mobility, hampers the formation and alignment of SSTR2 clusters along actin fibers, and impairs both SSTR2 recruitment to CCPs and SSTR2 internalization. These findings indicate that dynamic SSTR2-FLNA interactions critically control the nanoscale localization of SSTR2 at the plasma membrane and are required for coupling SSTR2 clustering to internalization. These mechanisms explain the critical role of FLNA in the control of SSTR2 expression and signaling and suggest the possibility of targeting SSTR2-FLNA interactions for the therapy of pharmacologically resistant GH-secreting pituitary tumors.

OBJECTIVE Rathke's cleft cyst (RCC) is a common sellar lesion which may cause visual impairment, hypopituitarism and headaches from mass effect. The natural history of these lesions is currently unclear. We investigated the natural history of RCCs and compared surgically treated patients with those treated conservatively. METHODS We performed a retrospective cohort study of patients diagnosed with a RCC between 1996 and 2016 at Stanford University and Ospedale Maggiore Policlinico di Milano. RESULTS Patients were divided into 2 cohorts: Group A, 72 subjects who underwent surgical resection of a symptomatic RCC, and Group B, 62 subjects managed conservatively. Compared to Group B, Group A subjects had larger RCCs (79% vs 22% had a largest diameter >10 mm, P

Pseudohypoparathyroidism is a rare endocrine disorder with an estimated prevalence of 1/100,000. It is characterized by hypocalcemia and hyperphosphatemia in the absence of vitamin D deficiency or impaired renal function. Research studies during the last 20 years have led to the identification of the molecular underlying cause of the disease, the characterization of the clinical and biochemical characteristics and the observation of an overlap between genetic and clinical manifestations. The creation of networks both for specialists (including endocrinologists, pediatricians, dermatologists, geneticists, molecular biologists…) and patients support groups brings up the opportunity of research advance, synergism and common objectives for families and investigators, improving the quality of information about the disease and its outcome, that, at the end, will improve both the knowledge and life of the patients and their families.

Objective To collect outcome data in a large cohort of patients with aggressive pituitary tumours (APT)/carcinomas (PC) and specifically report effects of temozolomide (TMZ) treatment. Design Electronic survey to ESE members Dec 2015–Nov 2016. Results Reports on 166 patients (40 PC, 125 APT, 1 unclassified) were obtained. Median age at diagnosis was 43 (range 4–79) years. 69% of the tumours were clinically functioning, and the most frequent immunohistochemical subtype were corticotroph tumours (45%). Ki-67 index did not distinguish APT from PC, median 7% and 10% respectively. TMZ was first-line chemotherapy in 157 patients. At the end of the treatment (median 9 cycles), radiological evaluation showed complete response (CR) in 6%, partial response (PR) in 31%, stable disease (SD) in 33% and progressive disease in 30%. Response was more frequent in patients receiving concomitant radiotherapy and TMZ. CR was seen only in patients with low MGMT expression. Clinically functioning tumours were more likely to respond than non-functioning tumours, independent of MGMT status. Of patients with CR, PR and SD, 25, 40 and 48% respectively progressed after a median of 12-month follow-up. Other oncological drugs given as primary treatment and to TMZ failures resulted in PR in 20%. Conclusion This survey confirms that TMZ is established as first-line chemotherapeutic treatment of APT/PC. Clinically functioning tumours, low MGMT and concurrent radiotherapy were associated with a better response. The limited long-term effect of TMZ and the poor efficacy of other drugs highlight the need to identify additional effective therapies.

An efficient intracellular response to somatostatin analogs (SSA) in pituitary tumors requires filamin A (FLNA). Since cAMP pathway plays an important role in GH-secreting pituitary tumors pathogenesis and FLNA is phosphorylated by PKA on S2152, aim of this study was to investigate in tumoral somatotrophs the impact of cAMP pathway activation and SSA stimulation on FLNA phosphorylation and the consequences on SST2 function. We found a PKA-mediated increase (2-fold) and SST2 agonist-induced decrease (-50%) of FLNA phosphorylation in GH3, GH4C1 and primary somatotroph tumor cells. This modification regulates FLNA function. Indeed, phosphomimetic S2152D FLNA mutant, but not phosphodeficient S2152A, abolished the known SSA antitumoral effects, namely: 1) inhibition of cell proliferation, reduction of cyclin D3 and increase of p27; 2) increase of cell apoptosis; 3) inhibition of cell migration via RhoA activation and cofilin phosphorylation. Coimmunoprecipitation and immunofluorescence assays showed that S2152A FLNA was recruited to activated SST2, whereas S2152D FLNA constitutively bound SST2 on the plasma membrane, but prevented Gαi proteins recruitment to SST2. In conclusion, we demonstrated that FLNA phosphorylation, promoted by cAMP pathway activation and inhibited by SSA, prevented SST2 signaling in GH-secreting tumoral pituitary cells.

Parathyroid glands are the main regulator of body mineral metabolism through parathormone (PTH) actions on bone and kidney. Experimental evidence suggests that PTH may have non-classical target organs such as adipose tissue, arterial vascular wall, cardiac muscle cells, and adrenal cortex cells, where it may play a role in controlling body energy, blood pressure, and metabolism. Cardiometabolic features have been investigated in the wide spectrum of clinical parathyroid disorders, from hyperparathyroidism to pseudohypoparathyroidism and hypoparathyroidism. Indeed, in parathyroid disorders, besides altered PTH secretion, impaired serum calcium levels and vitamin D status occur. Both calcium and vitamin D have been shown to regulate metabolism and to be associated with cardiovascular diseases. However, despite the complexity of parathyroid disorders, features of metabolic syndrome, such as obesity, insulin resistance, and glucose intolerance, arterial blood hypertension, and dyslipidemia, are frequently diagnosed in primary and secondary hyperparathyroidism as well as in pseudohyperparathyroidism. Here, we reviewed the most consistent data highlighting challenges and providing clinical remarks.

Hypoparathyroidism is a rare disease characterized by low serum calcium levels and absent or deficient parathyroid hormone level. Regarding the epidemiology of chronic hypoparathyroidism, there are limited data in Italy and worldwide. Therefore, the purpose of this study was to build a unique database of patients with chronic hypoparathyroidism, derived from the databases of 16 referral centers for endocrinological diseases, affiliated with the Italian Society of Endocrinology, and four centers for endocrine surgery with expertise in hypoparathyroidism, to conduct an epidemiological analysis of chronic hypoparathyroidism in Italy. The study was approved by the Institutional Review Board. A total of 537 patients with chronic hypoparathyroidism were identified. The leading etiology was represented by postsurgical hypoparathyroidism (67.6%), followed by idiopathic hypoparathyroidism (14.6%), syndromic forms of genetic hypoparathyroidism (11%), forms of defective PTH action (5.2%), non-syndromic forms of genetic hypoparathyroidism (0.9%), and, finally, other forms of acquired hypoparathyroidism, due to infiltrative diseases, copper or iron overload, or ionizing radiation exposure (0.7%). This study represents one of the first large-scale epidemiological assessments of chronic hypoparathyroidism based on data collected at medical and/or surgical centers with expertise in hypoparathyroidism in Italy. Although the study presents some limitations, it introduces the possibility of a large-scale national survey, with the final aim of defining not only the prevalence of chronic hypoparathyroidism in Italy, but also standards for clinical and therapeutic approaches.

La proteina Gs $\upalpha$ e un trasduttore di segnale intracellulare, utilizzato dalla maggior parte degli ormoni proteici. Sono descritte malattie da aumentata funzione della proteina Gs $\upalpha$ , la piu nota delle quali e la Sindrome di McCune Albright, e malattie da ridotta funzione della proteina Gs $\upalpha$ , quali lo pseudoipoparatiroidismo, disordine estremamente eterogeneo. La conoscenza dei meccanismi eziopatogenetici e dello spettro di manifestazioni cliniche all’interno di ciascuna entita si sono ampliati notevolmente negli ultimi anni. Obiettivo del presente articolo e fornire un update clinico-molecolare di queste patologie rare e proteiformi.

The term pseudohypoparathryoidism (PHP) refers to a group of rare genetic and epigenetic disorders characterized by resistance to the action of parathyroid hormone (PTH) that activates cAMP signaling in target cells. Together with pseudohypoparathyroidism, Albright hereditary osteodystrophy (AHO) and progressive osseous heteroplasia (POH) represent rare, related and deeply impairing disorders encompassing heterogeneous features, such as brachydactyly, ectopic ossifications, short stature, mental retardation and endocrine deficiencies due to resistance to the action of different hormones. The two main subtypes, PHP-Ia and PHP-Ib, are caused by mutations in GNAS exons 1-13 and methylation defects in the imprinted GNAS cluster respectively, while mutations in the PRKAR1A and PDE4D genes (also involved in mediating cAMP signalling) have been demonstrated in patients with acrodysostosis, a disease of bone formation with characteristics similar to AHO. The molecular overlap among these disorders indicates the need for different classification models and seriously alters our understanding of the mechanisms through which GNAS defects, together with the new recently described defects involving other components of the cAMP signalling cascade, cause AHO-related disorders.

Pseudohypoparathyroidism type Ia (PHP1A) is a rare endocrine disorder characterized by hypocalcemia, hyperphosphatemia, multiple hormonal resistance, and features of Albright hereditary osteodystrophy. When the phenotype is present but not associated with hormonal resistance, it is called psedopseudohypoparathyroidism (PPHP). Both entities have been associated to GNAS haploinsufficiency, and are mostly caused by inherited inactivating mutations at GNAS gene that codes for the stimulatory alpha subunit of G protein, although the cause remains unidentified in approximately 30% of patients.The aims of our work were 1) to identify GNAS locus defects in 112 patients with clinical diagnosis of PHP1A/PPHP and no point mutations at GNAS, to improve molecular diagnostic and genetic counseling; 2) to outline the underlying molecular mechanism(s).Methylation-specific-multiplex ligation-dependent probe amplification, qPCR, array comparative genomic hybridization, and long-PCR were used to search for genomic rearrangements at chromosome 20q and to identify their boundaries. We used different bioinformatic approaches to assess the involvement of the genomic architecture in the origin of the deletions.We discovered seven novel genomic deletions, ranging from 106-bp to 2.6-Mb. The characterization of five of seven deletion breakpoints and the definition of the putative molecular mechanisms responsible for these rearrangements revealed that Alu sequences play a major role in determining the genetic instability of the region.We observed that deletions at GNAS locus represent a significant cause of PPHP/PHP1A and that such defects are mostly associated with Alu-mediated recombination events. Their investigation revealed to be fundamental as, in some cases, they could be misdiagnosed as imprinting defects.

cAMP pathway plays a major role in the pathogenesis of cortisol-producing adrenocortical adenomas (CPA). cAMP-induced steroidogenesis is preceded by actin cytoskeleton reorganization, a process regulated by cofilin activity. In this study we investigated cofilin role in mediating cAMP effects on cell morphology and steroidogenesis in adrenocortical tumor cells. We demonstrated that forskolin induced cell rounding and strongly reduced phosphorylated (P)-cofilin/total cofilin ratio in Y1 (-52 ± 16%, p

Hypothyroidism may occur in association with congenital parathyroid disorders determining parathyroid hormone insufficiency, which is characterized by hypocalcemia and concomitant inappropriately low secretion of parathormone (PTH). The association is often due to loss of function of genes common to thyroid and parathyroid glands embryonic development. Hypothyroidism associated with hypoparathyroidism is generally mild and not associated with goiter; moreover, it is usually part of a multisystemic involvement not restricted to endocrine function as occurs in patients with 22q11 microdeletion/DiGeorge syndrome, the most frequent disorders. Hypothyroidism and hypoparathyroidism may also follow endocrine glands' damages due to autoimmunity or chronic iron overload in thalassemic disorders, both genetically determined conditions. Finally, besides PTH deficiency, hypocalcemia can be due to PTH resistance in pseudohypoparathyroidism; when hormone resistance is generalized, patients can suffer from hypothyroidism due to TSH resistance. In evaluating patients with hypothyroidism and hypocalcemia, physical examination and clinical history are essential to drive the diagnostic process, while routine genetic screening is not recommended.