Efficacy and safety of single-agent pan-human epidermal growth factor receptor (HER) inhibitor dacomitinib in locally advanced unresectable or metastatic skin squamous cell cancer.

BACKGROUND: In recurrent or metastatic (R/M) skin squamous cell cancer (sSCC) not amenable to radiotherapy (RT) or surgery, chemotherapy (CT) has a palliative intent and limited clinical responses. The role of oral pan-HER inhibitor dacomitinib in this setting was investigated within a clinical trial. METHODS: Patients with diagnosis of R/M sSCC were treated. Dacomitinib was started at a dose of 30 mg daily (QD) for 15 d, followed by 45 mg QD. Primary end-point was response rate (RR). Tumour samples were analysed through next-generation sequencing using a custom panel targeting 36 genes associated with sSCC. RESULTS: Forty-two patients (33 men; median age 77 years) were treated. Most (86%) received previous treatments consisting in surgery (86%), RT (50%) and CT (14%). RR was 28% (2% complete response; 26% partial response), disease control rate was 86%. Median progression-free survival and overall survival were 6 and 11 months, respectively. Most patients (93%) experienced at least one adverse event (AE): diarrhoea, skin rash (71% each), fatigue (36%) and mucositis (31%); AEs grade 3-4 occurred in 36% of pts. In 16% of cases, treatment was discontinued because of drug-related toxicity. TP53, NOTCH1/2, KMT2C/D, FAT1 and HER4 were the most frequently mutated genes. BRAF, NRAS and HRAS mutations were more frequent in non-responders, and KMT2C and CASP8 mutations were restricted to this subgroup. CONCLUSIONS: In sSCC, dacomitinib showed activity similar to what was observed with anti-epidermal growth factor receptor agents, and durable clinical benefit was observed. Safety profile was comparable to previous experiences in other cancers. Molecular pt selection could improve therapeutic ratio.

Correction to: Point shear wave ultrasound elastography with Esaote compared to real-time 2D shear wave elastography with supersonic imagine for the quantification of liver stiffness.

Unfortunately, in the first sentence under the section head "Point shear wave elastography", the transducer name was misspelled as CA541 (rather than CA451).

Point shear wave ultrasound elastography with Esaote compared to real-time 2D shear wave elastography with supersonic imagine for the quantification of liver stiffness.

PURPOSE: Different shear wave elastography (SWE) machines able to quantify liver stiffness (LS) have been recently introduced by various companies. The aim of this study was to investigate the agreement between point SWE with Esaote MyLab Twice (pSWE.ESA) and 2D SWE with Aixplorer SuperSonic (2D SWE.SSI). Moreover, we assessed the correlation of these machines with Fibroscan in a subgroup of patients. METHODS: A total of 81 liver disease patients and 27 subjects without liver disease accessing the ultrasound lab were considered. Exclusion criteria were liver nodules, BMI >35, and severe comorbidities. LS was sampled from the same intercostal space with both pSWE.ESA and 2D SWE.SSI and values were tested with Lin's analysis and Bland-Altman analysis (B&A). Agreement between each SWE machine and Fibroscan was assessed in 26 liver disease patients with Spearman correlation. RESULTS: Precision and accuracy between pSWE.ESA and 2D SWE.SSI were, respectively, 0.839 and 0.999. B&A showed a mean of only -0.2 kPa, with no systematic deviation between the techniques and limits of agreement at -11.6 and 11.3 kPa. Spearman's rho correlation versus Fibroscan was 0.849 for pSWE.ESA and 0.878 for 2D SWE.SSI. The relationship became less strict in the higher range of LS (≥15.2 kPa), corresponding to cirrhosis. CONCLUSION: The overall degree of concordance of pSWE.ESA and 2D SWE.SSI in measuring LS resulted remarkable, also when compared with Fibroscan. The less strict correlation for patients with LS in the higher range would not affect the staging of disease as such patients are anyhow classified as cirrhotic.

Management of tyrosine kinase inhibitors (TKI) side effects in differentiated and medullary thyroid cancer patients.

Four tyrosine kinase inhibitors (TKIs) have been recently licensed in thyroid cancer (TC), sorafenib and lenvatinib for differentiated TC, vandetanib and cabozantinib for medullary TC. Others TKIs such as axitinib, pazopanib, sunitinib, have been tested within phase II trials. The toxicity burden associated to TKIs is not negligible. Drug reductions and interruptions are common, definitive drug withdrawals have also been reported as well as toxic deaths in more rare cases. In this context, the prevention of toxicities is mandatory to allow patients to stay on treatment as long as possible without dose and schedule modifications. Both physicians and patients should be educated to recognize drug-related toxicities in order to manage them in an early phase. Tools (e.g. toxicities summary booklet) for physicians and patients could be considered to improve the knowledge on side effects management. Guidelines, whenever available, should be followed.

A randomized, double-blind, placebo-controlled, multicenter study of a ginger extract in the management of chemotherapy-induced nausea and vomiting (CINV) in patients receiving high-dose cisplatin.

BACKGROUND: The activity of ginger in the management of chemotherapy-induced nausea and vomiting (CINV) has been suggested, but design inadequacies, heterogeneity of the population, small numbers and poor quality of tested products limit the possibility to offer generalizable results. PATIENTS AND METHODS: We conducted a randomized, double-blind, placebo-controlled, multicenter study in patients planned to receive ≥2 chemotherapy cycles with high dose (>50 mg/m2) cisplatin. Patients received ginger 160 mg/day (with standardized dose of bioactive compounds) or placebo in addition to the standard antiemetic prophylaxis for CINV, starting from the day after cisplatin administration. CINV was assessed through daily visual-analogue scale and Functional Living Index Emesis questionnaires. The main objective was protection from delayed nausea; secondary end points included intercycle nausea and nausea anticipatory symptoms. RESULTS: In total, 121 patients received ginger and 123 placebo. Lung (49%) and head and neck cancer (HNC; 35%) were the most represented tumors. No differences were reported in terms of safety profile or compliance. The incidence of delayed, intercycle and anticipatory nausea did not differ between the two arms in the first cycle and second cycle. A benefit of ginger over placebo in Functional Living Index Emesis nausea score differences (day 6-day 1) was identified for females (P = 0.048) and HNC patients (P = 0.038). CONCLUSIONS: In patients treated with high-dose cisplatin, the daily addition of ginger, even if safe, did not result in a protective effect on CINV. The favorable effect observed on nausea in subgroups at particular risk of nausea (females; HNC) deserves specific investigation.

A phase II study of sorafenib in recurrent and/or metastatic salivary gland carcinomas: Translational analyses and clinical impact.

BACKGROUND: Pre-clinical and clinical evidence suggests a rationale for the use of anti-angiogenic agents, including sorafenib, in recurrent and/or metastatic salivary gland carcinomas (RMSGCs). This study evaluates the activity of sorafenib in patients with RMSGCs and also investigates whether the activity of sorafenib could be related to its main tailored targets (i.e. BRAF, vascular endothelial growth factor receptor 2 [VEGFR2], platelet-derived growth factor receptor α [PDGFRα] and ß, RET, KIT). PATIENTS AND METHODS: Patients received sorafenib at 400 mg BID. The primary end-point was response rate (RR) including complete response or partial response (PR); secondary end-points included RR according to Choi criteria, disease control rate (DCR), overall survival (OS), and progression-free survival (PFS). RESULTS: Thirty-seven patients (19 adenoid cystic cancers, ACC) were enrolled. Six PRs were recorded. RR was 16% (95% confidence interval [CI]: 6-32; 11% in ACC and 22% in non-ACC). Choi criteria could be applied in 30 out of 37 cases with a RR of 50% (95% CI: 31-69%); DCR was 76% (95% CI: 59-88%). Incidence of ≥G3 adverse events was 29.7%. Median PFS and OS for the entire population were 5.9 months and 23.4 months, respectively. Median PFS and OS were 8.9 and 26.4 months for ACC versus 4.2 and 12.3 months for non-ACC patients. All the cases showed expression of PDGFRß in the stroma and VEGFR2 in endothelial cells; PDGFRα positivity was found in the stroma of four (27%) cases. All except for two cases showed no PDGFRß, VEGFR2 and PDGFRα expression in the tumour cells. KIT expression was restricted to ACC and a weak RET expression was limited to one adenocarcinoma, not otherwise specified (NOS). No BRAF mutation was found. No correlation was observed between the sorafenib activity and the expression of its markers although all six responders (two ACC, one adenocarcinoma, NOS, one salivary duct cancer [SDC], one high-grade mucoepidermoid [HG-MEC] and one poorly-differentiated cancer) are enriched in the stromal component showing a PDGFRß immunodecoration. In ACCs, immunohistochemistry revealed MYB protein expression in 15/16 cases (94%) and the MYB-NFIB fusion oncogene was observed in 9/14 (64%). CONCLUSIONS: Sorafenib is the first anti-angiogenic agent to demonstrate activity in RMSGC patients, particularly in some histotypes such as HG-MEC, SDC and adenocarcinoma, NOS. The PDGFRß-positive rich stromal component characterising these histotypes and the lack of correlation between the activity of sorafenib and its targets suggests anti-angiogenic effect as the prevalent mechanism of action of sorafenib in SGCs.

Peripheral activities of growth hormone-releasing hormone.

Growth hormone (GH)-releasing hormone (GHRH) is produced by the hypothalamus and stimulates GH synthesis and release in the anterior pituitary gland. In addition to its endocrine role, GHRH exerts a wide range of extrapituitary effects which include stimulation of cell proliferation, survival and differentiation, and inhibition of apoptosis. Accordingly, expression of GHRH, as well as the receptor GHRH-R and its splice variants, has been demonstrated in different peripheral tissues and cell types. Among the direct peripheral activities, GHRH regulates pancreatic islet and ß-cell survival and function and endometrial cell proliferation, promotes cardioprotection and wound healing, influences the immune and reproductive systems, reduces inflammation, indirectly increases lifespan and adiposity and acts on skeletal muscle cells to inhibit cell death and atrophy. Therefore, it is becoming increasingly clear that GHRH exerts important extrapituitary functions, suggesting potential therapeutic use of the peptide and its analogs in a wide range of medical settings.

Ghrelin.

BACKGROUND: The gastrointestinal peptide hormone ghrelin was discovered in 1999 as the endogenous ligand of the growth hormone secretagogue receptor. Increasing evidence supports more complicated and nuanced roles for the hormone, which go beyond the regulation of systemic energy metabolism. SCOPE OF REVIEW: In this review, we discuss the diverse biological functions of ghrelin, the regulation of its secretion, and address questions that still remain 15 years after its discovery. MAJOR CONCLUSIONS: In recent years, ghrelin has been found to have a plethora of central and peripheral actions in distinct areas including learning and memory, gut motility and gastric acid secretion, sleep/wake rhythm, reward seeking behavior, taste sensation and glucose metabolism.

HCV genotype 1 subtypes (1a and 1b): similarities and differences in clinical features and therapeutic outcome.

AIM: To evaluate similarities and differences in HCV-1 subtypes 1a and 1b in the presenting clinical features and the response to peg-interferon and ribavirin (Peg/RIBA). PATIENTS AND METHODS: A total of 1,233 naïve patients with HCV genotype-1 infection, 159 (13%) with subtype 1a and 1,074 (87%) with subtype 1b were treated with Peg-IFN/RIBA at 12 Italian centers. Covariates included in the logistic model were age, gender, BMI, serum alanine aminotransferase, serum gamma-glutamiltranspeptidase (γGT), platelets counts, liver fibrosis, the occurrence of type 2 diabetes, baseline viremia, and IL28B genotype. RESULTS: At multivariate analysis, baseline characteristics differentiating patients with HCV-1a versus HCV-1b were young age, male gender, no F4 fibrosis, and no diabetes. SVR was achieved by 37% of patients with subtype 1b and 45% of those with subtype 1a, a nonsignificant difference of 8% (p = 0.069). In patients with subtype 1a, predictors of SVR were IL28B CC (OR 5.78, CI 1.98-16.83), RVR (OR 4.18, CI 1.66-10.55), female gender (OR 2.83, CI 1.83-6.78), and HCVRNA (OR 0.55, CI 0.32-0.96). In patients with subtype 1b, the ranking of predictors was levels RVR (OR 6.49, CI 4.32-9.73), IL28B CC (OR 3.32, CI 2.15-4.58), γGT (OR 1.59, CI 0.14-2.22), HCVRNA (OR 0.61, CI 0.47-0.79), and age (OR 0.01, CI 0.02-0.42). CONCLUSION: In Italy HCV-1 subtype 1a prevails in young male patients with less advanced liver damage, findings that imply a more recent spreading of the infection with this viral strain. The two HCV-1 subtypes appear equally responsive to Peg-IFN/RIBA, with IL28B genotyping and monitoring of RVR mostly influencing the therapeutic response.

Treatment-related outcome of oropharyngeal cancer patients differentiated by HPV dictated risk profile: a tertiary cancer centre series analysis.

BACKGROUND: To date, no treatment modality has been identified as more effective for oropharyngeal cancer (OPC), and no predictive factors are known to guide treatment decision for this disease. This retrospective study evaluates the differential effects of diverse treatment options for OPC according to patient risk profiles. PATIENTS AND METHODS: We considered two series of locally advanced squamous cell OPC patients treated with either surgery followed by radiotherapy (surgical series) or chemoradiation (CRT) with/without induction docetaxel, cisplatin and 5-fluorouracil (TPF) chemotherapy (CRT series). Smoking habits, tumor p16 expression/human papillomavirus (HPV) status and T and N stage were analyzed to stratify the patients according to Ang's risk profile (low, intermediate and high risk). Overall survival (OS) and disease-free survival were calculated with the Kaplan-Meier method. RESULTS: Globally, 171 patients were considered, 56 in surgical and 115 in CRT series. Patients were stratified in low- (20% of surgical and CRT groups), intermediate- (23% and 41%) and high-risk (57% and 39%) groups. In the surgical series, 5-year OS was 54.5%, 46.9% and 40.0% in low, intermediate and high Ang's risk profiles, respectively, whereas in the CRT series those were 100%, 78.9% and 46.7%, respectively. In the multivariable analyses, adjusting for inhomogeneity between the treatment group, the CRT effect was significantly higher in the low- and intermediate-risk groups (P-value for the interaction treatment risk group = 0.034 in the OS analysis). CONCLUSIONS: In this retrospective analysis, low- and intermediate-risk OPC patients had a better survival when treated with CRT compared with open surgery followed by radiation therapy. These data suggest that different treatment approaches might be essential in determining outcome results.

Preoperative chemotherapy in advanced resectable OCSCC: long-term results of a randomized phase III trial.

BACKGROUND: Data on preoperative chemotherapy in resectable oral cavity cancer are conflicting. We present the long-term results of a randomized trial of induction chemotherapy in resectable oral cavity cancer. PATIENTS AND METHODS: A randomized, parallel, multicentre trial evaluated the impact of three cycles of cisplatin 100 mg/m2 and fluorouracil 1000 mg/m2 (120-h infusion administered every 21 days) in stage T2-T4, N0-N2, previously untreated patients with advanced disease. Control group received upfront surgery. Postoperative radiation was offered to both arms when pathologic risk features were identified. The co-primary end points were the occurrence of locoregional or distant tumour relapse, and death. RESULTS: Among the 198 enrolled patients, with a median follow-up of 11.5 years, there was no difference in the incidence of locoregional relapse between chemotherapy and control group (P=0.6337), nor in distant metastasis development (P=0.1527). There was also no difference between groups in overall survival (P=0.3402). Patients with a pathological complete response (pCR) had higher probability of survival than those without (10-year OS: 76.2% versus 41.3%, P=0.0004). Late toxicities in patients with a minimum follow-up of 60 months (42 in each group) were similar between arms, except from fibrosis (cumulative incidence 40% versus 22% in chemotherapy arm) and grade 2 dysphagia (14% versus 5%). CONCLUSIONS: Long-term follow-up of this randomized trial confirmed the absence of survival benefit with preoperative chemotherapy in oral cavity cancer. Late toxicity was similar in the two arms except for fibrosis and dysphagia, which were less in the chemotherapy arm. The survival benefit for patients achieving a pCR was maintained.

The role of obestatin in glucose and lipid metabolism.

Obestatin is a 23 amino acid peptide encoded by the ghrelin gene, which, like ghrelin, is mainly produced by the stomach, as well as by a wide range of other tissues. Obestatin remains a controversial peptide, as the initial finding of its binding to the orphan receptor GPR39 and the inhibitory effect on food intake has been questioned. In fact, to date, its biological effects are still largely unknown, although it is becoming clear that obestatin is a pleiotropic hormone, exerting a variety of effects in different cell types and tissues. Indeed, besides regulating cell proliferation and survival, obestatin has been shown to regulate glucose and lipid metabolism, both in vitro, in pancreatic ß-cells and adipocytes, and in vivo in rodents. Furthermore, its positive effects on glucose homeostasis, combined with the anti-inflammatory actions, make this peptide appealing as a candidate for treating metabolic disorders such as insulin resistance and diabetes.

Metabolic effects of overnight continuous infusion of unacylated ghrelin in humans.

OBJECTIVE: To clarify the metabolic effects of an overnight i.v. infusion of unacylated ghrelin (UAG) in humans. UAG exerts relevant metabolic actions, likely mediated by a still unknown ghrelin receptor subtype, including effects on ß-cell viability and function, insulin secretion and sensitivity, and glucose and lipid metabolism. DESIGN: We studied the effects of a 16-h infusion (from 2100 to 1300  h) of UAG (1.0  µg/kg per h) or saline in eight normal subjects (age (mean±s.e.m.), 29.6±2.4 years; body mass index (BMI), 22.4±1.7  kg/m(2)), who were served, at 2100 and 0800  h respectively, with isocaloric balanced dinner and breakfast. Glucose, insulin, and free fatty acid (FFA) levels were measured every 20  min. RESULTS: In comparison with saline, UAG induced significant (P<0.05) changes in glucose, insulin, and FFA profiles. UAG infusion decreased glucose area under the curve (AUC) values by 10% (UAG(0 - 960  min): 79.0±1.7×10(3)  mg/dl per min vs saline(0- 960  min): 87.5±3.8×10(3)  mg/dl per min) and the AUC at night by 14% (UAG(180)(-)(660  min): 28.4±0.5×10(3)  mg/dl per min vs saline(180 - 660  min): 33.2±1.1×10(3)  mg/dl per min). The overall insulin AUC was not significantly modified by UAG infusion; however, insulin AUC observed after meals was significantly increased under the exposure to UAG with respect to saline at either dinner or breakfast. The FFA AUC values were decreased by 52% under the exposure to UAG in comparison with saline (UAG(0 - 960  min): 0.3±0.02×10(3)  mEq/l per min vs saline(0 - 960  min): 0.6±0.05×10(3)  mEq/l per min). CONCLUSIONS: Exposure to the i.v. administration of UAG improves glucose metabolism and inhibits lipolysis in healthy volunteers. Thus, in contrast to the diabetogenic action of AG, UAG displays hypoglycemic properties.

The ghrelin gene products and exendin-4 promote survival of human pancreatic islet endothelial cells in hyperglycaemic conditions, through phosphoinositide 3-kinase/Akt, extracellular signal-related kinase (ERK)1/2 and cAMP/protein kinase A (PKA) signalling pathways.

AIMS/HYPOTHESIS: Pancreatic islet microendothelium exhibits unique features in interdependent relationship with beta cells. Gastrointestinal products of the ghrelin gene, acylated ghrelin (AG), unacylated ghrelin (UAG) and obestatin (Ob), and the incretin, glucagon-like peptide-1 (GLP-1), prevent apoptosis of pancreatic beta cells. We investigated whether the ghrelin gene products and the GLP-1 receptor agonist exendin-4 (Ex-4) display survival effects in human pancreatic islet microendothelial cells (MECs) exposed to chronic hyperglycaemia. METHODS: Islet MECs were cultured in high glucose concentration and treated with AG, UAG, Ob or Ex-4. Apoptosis was assessed by DNA fragmentation, Hoechst staining of the nuclei and caspase-3 activity. Western blot analyses and pharmacological inhibition of protein kinase B (Akt) and extracellular signal-related kinase (ERK)1/2 pathways, detection of intracellular cAMP levels and blockade of adenylyl cyclase (AC)/cAMP/protein kinase A (PKA) signalling were performed. Levels of NO, IL-1ß and vascular endothelial growth factor (VEGF)-A in cell culture supernatant fractions were measured. RESULTS: Islet MECs express the ghrelin receptor GHS-R1A as well as GLP-1R. Treatment with AG, UAG, Ob and Ex-4 promoted cell survival and significantly inhibited glucose-induced apoptosis, through activation of PI3K/Akt, ERK1/2 phosphorylation and intracellular cAMP increase. Moreover, peptides upregulated B cell lymphoma 2 (BCL-2) and downregulated BCL-2-associated X protein (BAX) and CD40 ligand (CD40L) production, and significantly reduced the secretion of NO, IL-1ß and VEGF-A. CONCLUSIONS/INTERPRETATION: The ghrelin gene-derived peptides and Ex-4 exert cytoprotective effects in islet MECs. The anti-apoptotic effects involve phosphoinositide 3-kinase (PI3K)/Akt, ERK1/2 and cAMP/PKA pathways. These peptides could therefore represent a potential tool to improve islet vascularisation and, indirectly, islet cell function.

Tumor stage, human papillomavirus and smoking status affect the survival of patients with oropharyngeal cancer: an Italian validation study.

BACKGROUND: Tumor human papillomavirus (HPV) status strongly affects overall survival (OS) of oropharyngeal cancer (OPC) patients. Recently, three groups with different outcomes were identified based on HPV status, smoking history and tumor stage. Our objective was to validate this model using a single-institutional retrospective database. PATIENTS AND METHODS: Patients (n=120) diagnosed with OPC at our institution, treated with concomitant cisplatin plus radiotherapy (RT) (n=64), induction chemotherapy followed by concomitant chemoradiation (n=39) or RT alone (n=17), were stratified in three groups with respect to the risk of death (low 26, intermediate 46 and high 49 patients) according to tumor p16 expression as surrogate of HPV status, pack-years of tobacco smoking and nodal/tumor stage. Group-stratified Kaplan-Meier OS curves were estimated and compared using the log-rank test. RESULTS: The 2-year OS estimates were 100%, 86% and 70%, respectively. The difference between the survival curves was statistically significant (P=0.009). The Harrell's concordance index was 0.70. The calibration plot showed a good concordance between our results and those observed in the original study. CONCLUSIONS: This study validates the risk grouping previously identified. Risk-driven clinical decision making and trial designs will help in better defining the most appropriate treatment in OPC patients.

Docetaxel, cisplatin and 5-fluorouracil-based induction chemotherapy followed by intensity-modulated radiotherapy concurrent with cisplatin in locally advanced EBV-related nasopharyngeal cancer.

BACKGROUND: This monocentric study evaluates the activity and tolerability of docetaxel (Taxotere), cisplatin and 5-fluorouracil (5-FU) (TPF) induction chemotherapy followed by intensity-modulated radiotherapy (IMRT) concurrent with high-dose cisplatin in Epstein-Barr virus -related locally advanced undifferentiated nasopharyngeal cancer. PATIENTS AND METHODS: We retrospectively reviewed the records of patients who received induction docetaxel 75 mg/m(2) and cisplatin 75 mg/m(2) on day 1, and 5-FU 750 mg/m(2)/day (96-h continuous infusion). Following induction, patients received full doses of IMRT concurrently with cisplatin 100 mg/m(2) every 21 days for three cycles. RESULTS: Thirty patients received three TPF cycles (median). Induction was well tolerated; the main toxicity was neutropenia (33%, grade 3-4). During chemoradiotherapy, neutropenia (40%) and mucositis (43%) were the most frequent grade 3-4 adverse events. Mean dose of IMRT was 68.8 Gy. Worst late toxicity was xerostomia. Complete response rate was 93%. At 35 months, two patients had locoregional recurrence, three had distant metastases, and one had both. Three-year progression-free survival and overall survival were 79% [95% confidence interval (CI) 64% to 94%] and 87% (95% CI 74%- to 100%), respectively. CONCLUSIONS: In this high-stage nonendemic cancer population, TPF followed by high-dose cisplatin IMRT was promising; this treatment approach deserves evaluation in randomized trials.

Circulating obestatin levels in normal and Type 2 diabetic subjects.

BACKGROUND: Obestatin has been discovered as a new product of the ghrelin gene. Its physiological actions are still a matter of debate, but it seems that this peptide is likely to be involved in the control of insulin secretion and action as well as of adipocyte function. It has been already shown that obestatin secretion in humans is negatively modulated by food intake. AIM: To clarify obestatin secretion in normal subjects and in patients with Type 2 diabetes (T2D) in basal conditions and after a standardized meal. SUBJECTS/METHODS: Five normal subjects and 5 T2D patients were studied during infusion of saline (iv for over 5 h from -120 to +180 min). A standardized lunch was served at 0 min. Obestatin, glucose, and insulin levels were assayed at -120, -90, -60, -45, -30, -15, 0, 15, 30, 45, 60, 90, 120, 150, and 180 min. RESULTS: From -120 to 0 min, obestatin levels in normal and T2D subjects were similar (area under the curve: 32.3+/-5.6 pg/ml/min vs 31.1+/-1.0 pg/ml/min). After the meal, circulating obestatin levels underwent a clear decrease in normal subjects (0 min: 300.6+/-34.7 pg/ml vs nadir at 60 min: 161.8+/-29.4 pg/ml; p=0.002) but not in diabetic patients (0 min: 267.2+/-16.5 pg/ml vs nadir at 180 min: 226.0+/-10.5 pg/ml). CONCLUSION: This study shows that normal and diabetic subjects display similar levels of circulating obestatin in fasting condition. However patients with T2D look refractory to the inhibitory effect of meal on obestatin secretion.

Pluripotent stem cells isolated from human amniotic fluid and differentiation into pancreatic beta-cells.

Human amniotic fluid (HAF) contains multipotent stem cells [amniotic fluid-derived stem cells (AFSC)] which can differentiate into a variety of different cell types. Recently, we demonstrated that obestatin, a peptide encoded by the ghrelin gene, exerts anti-apoptotic effects in pancreatic beta-cells and human islets and increases the expression of genes involved in beta-cells differentiation. We investigated whether: 1) AFSC would differentiate into pancreatic beta-cells and 2) obestatin would increase beta-cells differentiation from AFSC. Fluorescence-activated cell sorting analysis and immunocytochemical staining showed the presence of mesenchymal and endothelial markers in AFSC. Real-time PCR evidenced the expression of Octamer binding transcription factor 4 (OCT-4), a marker of pluripotency, during the early differentiation phase. However, the beta-cells differentiation marker duodenal homeobox factor-1 (PDX-1) could not be detected. Obestatin increased OCT-4 expression but had no effect on beta-cells differentiation. These results suggest that, at least under the experimental conditions used in this study, AFSC do not differentiate into beta-cells and obestatin has no additional effect.

Does autophagy have a license to kill mammalian cells?

Macroautophagy is an evolutionarily conserved vacuolar, self-digesting mechanism for cellular components, which end up in the lysosomal compartment. In mammalian cells, macroautophagy is cytoprotective, and protects the cells against the accumulation of damaged organelles or protein aggregates, the loss of interaction with the extracellular matrix, and the toxicity of cancer therapies. During periods of nutrient starvation, stimulating macroautophagy provides the fuel required to maintain an active metabolism and the production of ATP. Macroautophagy can inhibit the induction of several forms of cell death, such as apoptosis and necrosis. However, it can also be part of the cascades of events that lead to cell death, either by collaborating with other cell death mechanisms or by causing cell death on its own. Loss of the regulation of bulk macroautophagy can prime self-destruction by cells, and some forms of selective autophagy and non-canonical forms of macroautophagy have been shown to be associated with cell demise. There is now mounting evidence that autophagy and apoptosis share several common regulatory elements that are crucial in any attempt to understand the dual role of autophagy in cell survival and cell death.

The continuous infusion of acylated ghrelin enhances growth hormone secretion and worsens glucose metabolism in humans.

CONTEXT: Acylated ghrelin (AG) has been discovered as a natural ligand of the GH secretagogue receptor type 1a and is now recognized as an important orexigenic factor. Besides stimulation of GH secretion and appetite, it exerts other central and peripheral actions including modulation of insulin secretion, glucose and lipid metabolism. OBJECTIVE: To define the effects of the continuous iv infusion of AG in humans with particular attention to metabolic parameters. MATERIALS AND METHODS: We studied the effects of 16- h (from 21:00 to 13:00 h) infusion of AG (0.5 microg/kg/h) or saline in 8 young volunteers who were provided with isocaloric balanced meals. GH, cortisol, insulin, glucose, free fatty acid (FFA), and ghrelin levels were assayed every 20 min. RESULTS: AG infusion increased circulating total ghrelin to a steady state that was maintained over 16 h infusion of the peptide. With respect to saline, AG infusion significantly modified GH, cortisol, insulin, and glucose profiles and decreased FFA area under the curve (p<0.01). AG increased GH pulse frequency and approximate entropy (p<0.05). AG enhanced the glucose response to both dinner (p<0.02) and breakfast (p<0.03). AG infusion blunted the early insulin response to dinner (p<0.03) but enhanced the second-phase insulin response to dinner and breakfast (p<0.05). CONCLUSIONS: The continuous exposure to AG in humans enhances somatotroph secretion but also worsens glucose metabolism, although it inhibits lipolysis. These findings in normal young volunteers are consistent with data from studies in animals and suggest that acylated ghrelin is likely to play a negative role in glucose metabolism.