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Objective Lanreotide Autogel® 120 mg (ATG120; Ipsen S.p.A, Milan, Italy) is a high-dose, sustained-release aqueous gel formulation, supplied in a prefilled syringe and given by deep subcutaneous injection. The aim of this study was to compare efficacy and tolerability of ATG120 given every 4–8 weeks with those of octreotide LAR (o-LAR) given every 4 weeks. Design patients and intervention A phase III multicentre Italian open clinical study of 23 acromegalic patients (15 female, 8 male). All patients had received o-LAR for 6–18 months and, after 3 months wash out, ATG120 was given every 6 weeks for a total of four injections (Period 1). Then the interval between ATG120 injections was adjusted according to three different schemes: every 4, 6 or 8 weeks depending on GH levels (GH > 2·5 µg/l; 1 < GH ≤ 2·5 µg/l; GH ≤ 1 µg/l, respectively). ATG120 was given for a further two to three doses, with a final assessment (Period 2) at Week 34, 36 or 42. Measurements Hormonal (GH and IGF-I) and clinical efficacy and tolerability. Results ATG120 induced a significant GH decrease from 9·9 ± 11·3 at baseline (Visit 1) to 3·5 ± 5·7 at the end of Period 1 ( P < 0·01) and to 3·8 ± 5·7 µg/l at the final visit ( P < 0·01). IGF-I also decreased from 544 ± 312 at baseline (Visit 1) to 318 ± 181 at Period 1 and to 356 ± 187 µg/l at the final visit (both P < 0·05 vs. baseline). The frequency of ATG120 administrations was adjusted to every 4 weeks in 12 patients, every 6 weeks in 4 patients and every 8 weeks in 6 patients; 1 patient withdrew before the dose adjustment. Serum GH and IGF-I achieved at the end of Period 1 and Period 2 were similar to those reached with o-LAR. The number of patients who achieved GH < 2·5 µg/l was comparable between o-LAR (43%) and ATG120 at Period 1 (48%) and at Period 2 (62%). Normal IGF-I levels were recorded in 8 patients during o-LAR (35%), 11 during ATG Period 1 (48%) and 10 at the final visit (43%). Last, 4 patients showed a better response to ATG120 and 2 to o-LAR. Conclusions Lanreotide Autogel 120 mg is an effective and well-tolerated therapy for acromegaly. In approximately half of patients ATG120 may be administered every 6–8 weeks, instead of every 4 weeks, without lost of efficacy. [ABSTRACT FROM AUTHOR]

Abstract Background The control of growth and nutritional status in the foetus and neonate is a complex mechanism, in which also hormones produced by adipose tissue, such as adiponectin and leptin are involved. The aim of this study was to evaluate levels of adiponectin, leptin and insulin in appropriate (AGA) and small for gestational age (SGA) children during the 1st year of life and to correlate these with auxological parameters. Methods In 33 AGA and 29 SGA infants, weight, length, head circumference, glucose, insulin, adiponectin and leptin levels were evaluated at the second day of life, and at one, six and twelve months, during which a portion of SGA could show catch-up growth (rapid growth in infants born small for their gestational age). Results Both total and isoform adiponectin levels were comparable between AGA and SGA infants at birth and until age one year. These levels significantly increased from birth to the first month of life and then decreased to lower values at 1 year of age in all subjects. Circulating leptin concentrations were higher in AGA (2.1 ± 4.1 ng/ml) than in SGA neonates (0.88 ± 1.03 ng/ml, p < 0.05) at birth, then similar at the 1st and the 6th month of age, but they increased in SGA from six months to one year, when they showed catch-up growth. Circulating insulin levels were not statistically different in AGA and SGA neonates at any study time point. Insulin levels in both AGA and SGA infants increased over the study period, and were significantly lower at birth compared to one, six and 12 months of age. Conclusions During the first year of life, in both AGA and SGA infants a progressive decrease in adiponectin levels was observed, while a difference in leptin values was correlated with the nutritional status.

Introduction: In the last decade, GEP-NET nomenclature has been twice reviewed. The 2000 WHO classification had poor prognostic power in well-differentiated (WD) neoplasms which led to the introduction of two new important parameters: grade and stage, by ENETS; the former became part of the new 2010 WHO classification. Aim(s): Considering the recent introduction of grade and stage, their external validation has been called for in the literature. Since these are important tools in the management of patients, our aim was to reclassify retrospectively with grade and stage our series and correlate with follow-up. Materials and methods: From the histopathology archive at our center, 170 GEPNETs (1993-2011) were identified. Until now, 50 patients have been reclassified. Mean age at diagnosis was 56 years, F:M ratio was 1:1.2 and mean follow-up was 56 months (2-196). Results: Correlating differentiation with overall survival (OS), WD NETs had a strikingly better outcome with respect to poorly differentiated ones. However, only grade identified a subgroup of patients with WD lesions with less favorable clinical behavior (OS at 5 yrs: G1 - 96% v. G2 - 50%). Stage was also useful though not statistically significant in our small series. Conclusion: Our series confirms the importance of grade and stage in prognostic stratification. Retrospective classification of patients who may not have been previously graded or staged may influence the choice of therapeutic options in the future. [ABSTRACT FROM AUTHOR]

First-generation somatostatin receptor ligands (fg-SRLs), such as octreotide (OCT), represent the first-line medical therapy in acromegaly. Fg-SRLs show a preferential binding affinity for somatostatin receptor subtype-2 (SST 2 ), while the second-generation ligand, pasireotide (PAS), has high affinity for multiple SSTs (SST 5 > SST 2 > SST 3 > SST 1 ). Whether PAS acts via SST 2 in somatotroph tumors, or through other SSTs (e.g., SST 5 ), is a matter of debate. In this light, the combined treatment OCT+PAS could result in additive/synergistic effects. We evaluated the efficacy of OCT and PAS (alone and in combination) on growth hormone (GH) secretion in primary cultures from human somatotroph tumors, as well as on cell proliferation, intracellular signaling and receptor trafficking in the rat GH4C1 cell line. The results confirmed the superimposable efficacy of OCT and PAS in reducing GH secretion (primary cultures), cell proliferation, cAMP accumulation and intracellular [Ca 2+ ] increase (GH4C1 cells), without any additive effect observed for OCT+PAS. In GH4C1 cells, co-incubation with a SST 2 -selective antagonist reversed the inhibitory effect of OCT and PAS on cell proliferation and cAMP accumulation, while both compounds resulted in a robust internalization of SST 2 (but not SST 5 ). In conclusion, OCT and PAS seem to act mainly through SST 2 in somatotroph tumor cells in vitro, without inducing any additive/synergistic effect when tested in combination.

Context: Discordant growth hormone (GH) and insulin-like growth factor-1 (IGF-1) values are frequent in acromegaly., Objective: To evaluate the impact of different GH cutoffs on discordance rate. To investigate whether the mean of consecutive GH measurements impacts discordance rate when matched to the last available IGF-1 value., Design: Retrospective study., Setting: Referral center for pituitary diseases., Patients: Ninety acromegaly patients with at least 3 consecutive evaluations for GH and IGF-1 using the same assay in the same laboratory (median follow-up 13 years)., Interventions: Multimodal treatment of acromegaly., Main Outcome Measures: Single fasting GH (GHf) and IGF-1 (IGF-1f). Mean of 3 GH measurements (GHm), collected during consecutive routine patients' evaluations., Results: At last evaluation GHf values were 1.99 ± 2.79 µg/L and age-adjusted IGF-1f was 0.86 ± 0.44 × upper limit of normality (mean ± SD). The discordance rate using GHf was 52.2% (cutoff 1 µg/L) and 35.6% (cutoff 2.5 µg/L) (P = 0.025). "High GH" discordance was more common for GHf <1.0 µg/L, while "high IGF-1" was predominant for GHf <2.5 µg/L (P < 0.0001). Using GHm mitigated the impact of GH cutoffs on discordance (GHm <1.0 µg/L: 43.3%; GHm <2.5 µg/L: 38.9%; P = 0.265). At receiver-operator characteristic curve (ROC) analysis, both GHf and GHm were poor predictors of IGF-1f normalization (area under the curve [AUC] = 0.611 and AUC = 0.645, respectively). The prevalence of disease-related comorbidities did not significantly differ between controlled, discordant, and active disease patients., Discussion: GH/IGF-1 discordance strongly depends on GH cutoffs. The use of GHm lessen the impact of GH cutoffs. Measurement of fasting GH levels (both GHf and GHm) is a poor predictor of IGF-1f normalization in our cohort., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Pituitary-directed medical treatment for Cushing's disease (CD) is currently represented by membrane receptor targeting drugs (somatostatin analogs and dopamine agonists). Somatostatin and dopamine receptors are regulated by β-arrestins, which have been shown to be differentially regulated by glucocorticoids in non-neuroendocrine cells. In this study we investigated the effects of glucocorticoids on β-arrestin expression in corticotroph tumor cells. First, AtT20 cells, a mouse model of CD, were exposed to dexamethasone (Dex) at different time points and β-arrestin expression was evaluated at mRNA and protein levels. Futhermore, β-arrestin mRNA expression was evaluated in 17 human corticotroph adenoma samples and correlated to patients' pre-operative cortisol levels. We observed that Dex treatment induced a time-dependent increase in β-arrestin 1 mRNA expression and a decrease in β-arrestin 2. The same modulation pattern was observed at protein level. Dex-mediated modulation of β-arrestins was abolished by co-treatment with mifepristone, and Dex withdrawal restored β-arrestin expression to basal levels after 72 h. The evaluation of β-arrestin mRNA in corticotroph adenomas from CD patients with variable disease activity showed a significant positive correlation between β-arrestin 1 mRNA and urinary cortisol levels. The effect of glucocorticoids on β-arrestin levels was confirmed by the analysis of two samples from a single patient, which underwent adenomectomy twice, with different pre-operative cortisol levels. In conclusion, glucocorticoids induce an inverse modulation of the two β-arrestin isofoms in corticotroph tumor cells. Since β-arrestins regulate membrane receptor functions, this finding may help to better understand the variable response to pituitary-targeting drugs in patients with Cushing's disease.

Endogenous somatostatin shows anti-secretory effects in both physiological and pathological settings, as well as inhibitory activity on cell growth. Since somatostatin is not suitable for clinical practice, researchers developed synthetic somatostatin receptor ligands (SRLs) to overcome this limitation. Currently, SRLs represent pivotal tools in the treatment algorithm of neuroendocrine tumors (NETs). Octreotide and lanreotide are the first-generation SRLs developed and show a preferential binding affinity to somatostatin receptor (SST) subtype 2, while pasireotide, which is a second-generation SRL, has high affinity for multiple SSTs (SST 5 > SST 2 > SST 3 > SST 1 ). A number of studies demonstrated that first-generation and second-generation SRLs show distinct functional properties, besides the mere receptor affinity. Therefore, the aim of the present review is to critically review the current evidence on the biological effects of SRLs in pituitary adenomas and neuroendocrine tumors, by mainly focusing on the differences between first-generation and second-generation ligands.

Background: Pasireotide is a second-generation somatostatin (SRIF) receptor ligand (SRL), approved for medical treatment of acromegaly and Cushing's disease (CD). The molecule is a stable cyclohexapeptide synthetized based on SRIF structure. Differently from first-generation SRLs (e.g. octreotide), preferentially binding somatostatin receptor (SST) subtype 2 (SST 2 ), pasireotide has high affinity for multiple SSTs (SST 5  > SST 2  > SST 3  > SST 1 ). Interestingly, early preclinical studies demonstrated that pasireotide shows distinct functional properties compared to SRIF and first-generation SRLs when binding SSTs., Methods: We aimed to highlight the differential receptor-targeted action of pasireotide in the treatment of somatotroph and corticotroph adenomas, throughout the critical revision of preclinical studies carried out on acromegaly and CD models., Results: Different authors demonstrated that the antisecretory effect of pasireotide in somatotroph adenoma cell cultures is comparable to that of the SST 2 -preferential agonist octreotide. Some reports even show a direct correlation between SST 2 mRNA expression and GH reduction after pasireotide treatment, thus laying for a predominant role of SST 2 in driving pasireotide efficacy in somatotropinomas in vitro. On the other hand, the inhibitory effect of pasireotide on ACTH secretion in corticotropinoma cells seems to be mainly mediated by SST 5 . Indeed, most reports show a higher potency and efficacy of pasireotide compared to SST 2 preferential agonists, while functional studies confirm the pivotal role of SST 5 targeting in corticotroph cells., Conclusions: The analysis of preclinical studies carried out in somatotroph and corticoph adenomas points out that pasireotide shows a cell-specific activity, exerting its biological effects via different SSTs in the different adenoma histotypes.

Purpose: Epidemiological data are pivotal for the estimation of disease burden in populations., Aim: Of the study was to estimate the incidence and prevalence of acromegaly in Italy along with the impact of comorbidities and hospitalization rates as compared to the general population., Methods: Retrospective epidemiological study (from 2000 to 2014) and case control-study. Data were extracted from the Health Search Database (HSD). HSD contains patient records from about 1000 general practitioners (GPs) throughout Italy, covering a population of more than 1 million patients. It includes information about patient demographics and medical data including clinical diagnoses and diagnostic tests., Results: At the end of the study period, 74 acromegaly patients (out of 1,066,871 people) were identified, resulting in a prevalence of 6.9 per 100,000 inhabitants [95% CI 5.4-8.5]. Prevalence was higher in females than men (p = 0.004), and showed a statistically significant trend of increase over time (p < 0.0001). Overall, incidence during the study period was 0.31 per 100,000 person-years. Hypertension and type II diabetes mellitus were the comorbidities more frequently associated with acromegaly (31.3 and 14.6%, respectively) and patients were more likely to undergo a high frequency of yearly hospitalization (≥3 accesses/year, p < 0.001) compared to sex-age matched controls., Conclusions: This epidemiological study on acromegaly carried out using a large GP-based database, documented a disease prevalence of about 7 cases per 100,000 inhabitants. As expected, acromegaly was associated with a number of comorbidities (mainly hypertension and type II diabetes mellitus) and a high rate of patients' hospitalization.

Previous evidence supports a role for growth hormone (GH)-insulin-like growth factor (IGF)-I deficiency in the pathophysiology of osteopenia/osteoporosis in adult thalassemia. Moreover, serum IGF-II has never been studied in this clinical condition. Thus, we elected to study the GH secretory status and the levels of circulating somatomedins, correlating these parameters with bone mineral density (BMD) and biochemical markers of bone turnover. A hundred and thirty-nine normal weight adult thalassemic patients (72 men and 67 women) were studied. Lumbar and femoral neck BMD were measured in 106/139 patients. Sixty-eight patients underwent growth hormone releasing hormone plus arginine testing. Measurement of baseline IGF-I and IGF-II was performed in all patients, while osteocalcin, C-terminal telopeptide of type I collagen (CTx), and urinary cross-linked N-telopeptides of type I collagen (NTx) were assayed in 95 of them. Femoral and lumbar osteoporosis/Z score below the expected range for age were documented in 61.3 and in 56.6 % of patients, respectively. Severe GH deficiency (GHD) was demonstrated in 27.9 % of cases, whereas IGF-I SDS was low in 86.3 %. No thalassemic patients displayed circulating levels of IGF-II below the reference range. GH peaks were positively correlated with femoral, but not lumbar, Z score. No correlations were found between GH peaks and osteocalcin, CTx and NTx. GH peaks were positively correlated with IGF-I values, which in their turn displayed a positive correlation with osteocalcin, CTx, and NTx. No correlations emerged between IGF-I values and either femoral or lumbar Z scores. No correlations were found between IGF-II and any of the following parameters: GH peaks, osteocalcin, CTx, NTx, femoral Z score, and lumbar Z score. Our study, besides providing for the first time evidence of a normal IGF-II production in thalassemia, contributes to a better understanding of the involvement of the somatotropin-somatomedin axis in the pathophysiology of bone demineralization in this disease. In particular, the contribution of GHD to femoral osteoporosis appears to be likely mediated by locally produced rather than circulating IGF-I.

The actions of somatostatin (SRIF) are mediated by specific G protein-coupled receptors, named SRIF receptor (SSTR) subtypes 1, 2, 3 and 5. SRIF binding to SSTR activates a series of second messenger systems, resulting in the inhibition of calcium channels and adenylate cyclase activity, ultimately leading to inhibition of hormone secretion, while stimulation of other second messengers, such as phosphotyrosine phosphatases play a role in the control of cell growth. The SSTR and dopamine receptor families share a 30% sequence homology and appear to be structurally related. The knowledge on the pathophysiology of these two families of G protein-coupled receptors in neuroendocrine tumors has progressively increased due to the new insights in receptor dimerization, internalization and trafficking. Depending on the expression of different SSTRs in tissues, their combinations and interactions affect the functionality of the subtypes expressed and the influence of the microenvironment, the response to ligands and, by consequence, the response to treatment can be very different.

The objective of this study is to assess the secretory pattern of GH after Oral Glucose Tolerance Test (OGTT) or day-curve (DC), in relation with IGF-I and to evaluate the influence of therapy on OGTT. A retrospective analysis in 279 OGTTs performed in 93 acromegalic patients in our unit from January 1988 to December 2005, in 77 patients also DC data were retrived. GH concentration was evaluated by 3 different systems (RIA, IRMA and chemiluminescence assays), and IGF-I by two RIAs. About 12% of OGTT samples were discordant with the baseline, while discordance between nadir and 120th minute was much lower (5%), with all discordant values, except one, near the cut-off lines. Correlation between DC and OGTT data was around 0.99 among all values, discordance rate between nadir and minimum DC was much lower than that with mean DC. In almost 80% of cases there was a complete concordance between OGTT and DC results, and in about 30% IGF-I was discordant with GH. Correlation analysis between IGF-I and GH was highest with DC data and lowest with OGTT baseline (T0). Considering different treatments discrepancy rates between GH and IGF-I were comparable. The best GH parameter is the minimum GH DC, although in the clinical practice the evaluation of OGTT GH in association with IGF-I is the most practical approach. In this case, the basal and T120 GH values can replace multiple sampling. Different treatment modalities do not influence the discordance rate between GH and IGF-I.

Thyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism and account for less than 2% of pituitary adenomas. Medical therapy with somatostatin analogues (SSAs) effectively reduces TSH secretion in approximately 80% of patients and induces shrinkage in about 45% of tumors. According with previous data, resistance to SSA treatment might be due to heterogeneity in somatostatin receptors (SSTRs) expression. We report the case of TSHoma in a 41-year-old man treated with octreotide LAR that caused a dramatic decrease of TSH and thyroid hormones and tumor shrinkage already after 3 months of pre-surgical therapy. In search of potential molecular determinants of octreotide effectiveness, we measured, in primary cultures from this tumor, SSTR and dopamine D2 receptor (D2R) expression, and octreotide and/or cabergoline effects on TSH secretion and cell proliferation. SSTR5 and D2R expression was higher than SSTR2. Octreotide significantly inhibited TSH secretion more effectively than cabergoline (P<0.001), whereas the combined treatment was comparable with cabergoline alone. Similarly, octreotide resulted more effective than cabergoline on cell proliferation, while the combination did not show any additive or synergistic effects. In conclusion, the significant antisecretive and antiproliferative effect of octreotide in this patient might be related to the high expression of SSTR5, in the presence of SSTR2. After reviewing the literature, indeed, in line with previous observations, we hypothesize that SSTR5/SSTR2 ratio in TSHomas may represent a useful marker in predicting the outcome of therapy with SSAs. The role of D2R should be further explored considering that the presence of D2R can influence SSTRs functionality., (© Springer Science+Business Media, LLC 2010)