11-Keto-ß-Boswellic Acids Prevent Development of Autoimmune Reactions, Insulitis and Reduce Hyperglycemia During Induction of Multiple Low-Dose Streptozotocin (MLD-STZ) Diabetes in Mice.

The aim of the work was to study whether or not 11-keto-ß-boswellic acids prevent induction of autoimmune reactions, insulitis, and hyperglycemia in the model of multiple low-dose streptozotocin (MLD-STZ) diabetes. Using male mice (n = 6) diabetes was induced by daily i.p. injections of 40 mg/kg STZ for 5 days. In a second series together with STZ, daily i. p. injections of 11-keto-ß-boswellic acid (KBA) and O-acetyl-11-keto-ß-boswellic acid (AKBA) (7.5 and 15.0 mg/kg) were applied for 10 days. Thereafter, pro-and anti-inflammatory cytokines in the blood, histochemistry of pancreatic islets, and blood glucose levels were assayed. Five days after the last injection of STZ, a significant burst of pro-and anti-inflammatory cytokines in the blood, infiltration of lymphocytes (CD3) into pancreatic islets, and appearance of peri-insular apoptotic cells were observed. Plasma glucose increased significantly (124.4 ± 6.65 vs. 240.2 ± 27.36 mg/dl, p <0.05). Simultaneous treatment with KBA and AKBA significantly reduced pro-and anti-inflammatory cytokines (IFN-γ p < 0.01, p < 0.01; IL-1A p < 0.001, p < 0.001; IL-1B p < 0.001, p < 0.001; IL-2 p < 0.001, p < 0.001; IL-6 p < 0.01, p < 0.001; TNF-α p < 0.05, p < 0.001; IL-4 p < 0.01, p < 0.001; IL-10 p < 0.001, p < 0.001) in the blood. No infiltration of lymphocytes into pancreatic islets and appearance of peri-insular cells were detected. Moreover, KBA and AKBA reduced STZ-mediated increase of blood glucose on day 10 to 163.25 ± 16.6 (p < 0.05) and 187.6 ± 19.5 mg/dl (p < 0.05), respectively. In the model of MLD-STZ induced diabetes KBA and AKBA prevent cytokine burst, development of insulitis and reduce increase of blood glucose through "silencing" a forced-up immune reaction.

Age-dependent decline of ß-cell function in type 1 diabetes after diagnosis: a multi-centre longitudinal study.

AIMS: C-peptide secretion is currently the only available clinical biomarker to measure residual ß-cell function in type 1 diabetes. However, the natural history of C-peptide decline after diagnosis can vary considerably dependent upon several variables. We investigated the shape of C-peptide decline over time from type 1 diabetes onset in relation to age at diagnosis, haemoglobin A1c (HbA1c) levels and insulin dose. METHODS: We analysed data from 3929 type 1 diabetes patients recruited from seven European centres representing all age groups at disease onset (childhood, adolescence and adulthood). The influence of the age at onset on ß-cell function was investigated in a longitudinal analysis at diagnosis and up to 5-years follow-up. RESULTS: Fasting C-peptide (FCP) data at diagnosis were available in 3668 patients stratified according to age at diagnosis in four groups (<5 years, n = 344; >5 years < 10 years, n = 668; >10 years < 18 years, n = 991; >18 years, n = 1655). FCP levels were positively correlated with age (p < 0.001); the subsequent decline in FCP over time was log-linear with a greater decline rate in younger age groups (p < 0.0001). CONCLUSIONS: This study reveals a positive correlation between age at diagnosis of type 1 diabetes and FCP with a more rapid decline of ß-cell function in the very young patients. These data can inform the design of clinical trials using C-peptide values as an end-point for the effect of a given treatment.

Control of CYP11B2/CYP11B1 expression ratio and consequences for the zonation of the adrenal cortex.

Access of corticotropin to glucocorticoid synthesis in adrenocortical cells is provided by the expression of the ACTH receptor (MC2R). Activation of the MC2R increases stimulatory G-protein, adenylyl cyclase, and protein kinase A (PKA) activities. Furthermore, PKA phosphorylates transcription factors that have a stimulating effect on glucocorticoid synthesis. Sensitivity of adrenocortical cells to renin/angiotensin-2 is conferred by the expression of the inhibitory G-protein-linked angiotensin-2 type 1 receptor (AT1R) that additionally associates to the phospholipase C-activating G-protein q. The AT1R is connected to the adrenal potassium sensory system and regulates calcium influx as well as phospholipase C-ß (PLC-ß) and thus calmodulin kinase-dependent transcription of steroidogenic enzymes. While AT1R signaling suppresses the influence of corticotropin on the generation of cyclic adenosine monophosphate, the expression of the AT1R and its associated enzyme activities are under the control of glucocorticoids. Thus, dominance of one of the two signaling pathways is dependent on two factors: the extracellular concentration of their ligands and the products of their signaling pathways. These findings are in favor of the hypothesis that the centripetal blood flow through the adrenal gland builds up a glucocorticoid gradient creating a morphogenetic field along which adrenal cortical cells adopt different functional states, leading to the typical zonation of the adrenal cortex.

HLA-A2 phenotype may be protective against Graves' disease but not against Hashimoto's thyroiditis in Caucasians.

Graves' disease (GD) and Hashimoto's thyroiditis (HT) are the most common autoimmune thyroid diseases (AITDs) affecting up to 5% of the general population. In Caucasians HT has a prevalence of up to 4.60% and GD a prevalence of 1-2%. The aim of this study was to investigate the association between HLA-A2 and the AITDs GD and HT among Caucasians. HLA alleles of 33 patients with GD and 75 patients with HT were determined by serological typing. The frequency of HLA A2 was significantly reduced in GD (p=0.033) but not in HT (p=n.s.) as compared to control samples. In individuals positive for HLA-A2 odds ratio for protection from GD was found to be 2.8. This study supports the hypothesis that genetic predisposition to GD is not restricted to MHC class II molecules. The significant negative association between HLA A2 and GD supports the hypothesis that MHC class I genes may be relevant for the protection from GD. In contrast the nonsignificant results for HT indicate that this association may not apply to AITDs in general.

Griseofulvin inhibits the growth of adrenocortical cancer cells in vitro.

Supernumerary centrosomes and aneuploidy are associated with a malignant phenotype of tumor cells. Centrosomal clustering is a mechanism used by cancer cells with supernumerary centrosomes to solve the threatening problem of multipolar spindles. Griseofulvin is an antifungal substance that interferes with the microtubule apparatus and inhibits centrosomal clustering. It has also been demonstrated that griseofulvin inhibits the growth of tumor cells in vitro and in vivo. However, it is not yet known whether treatment with griseofulvin inhibits growth of adrenocortical tumor cells. We studied the viability and antiproliferative effects of griseofulvin on cultured NCI-H295R adrenocortical carcinoma cells using Wst-1-, BrdUrd-, and [³H]-thymidine assays. For the detection of apoptosis we used a caspase 3/7 cleavage assay and light microscopy techniques. We observed that incubation with griseofulvin for 24-48 h leads to a decrease in the viability and proliferation of NCI-H295R cells in a dose-dependent manner. Significant effects could be observed after incubation with griseofulvin as measured by Wst-1-, BrdUrd-, and [³H]dT- uptake assays. Apoptosis of NCI-H295R cells was increased in a dose-dependent manner up to 4.5-fold after incubation with griseofulvin 40 µM for 24 h as shown by caspase 3/7 cleavage assay and light microscopy. With regard to new treatment strategies for adrenocortical cancer, griseofulvin, and possibly other agents, which interfere with the microtubule apparatus and inhibit centrosomal clustering, may turn out to be interesting targets for further research.

Evidence for an exercise induced increase of TNF-α and IL-6 in marathon runners.

Regular physical activity of moderate intensity improves cardiovascular risk factors including low-grade inflammation. However, acute vigorous exercise such as marathon running results in marked increases of circulating pro-inflammatory markers. Up to now, the origin of this pro-inflammatory boost is still debated equivocally. We analyzed the change of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and leptin from pre- to immediately post-race in 15 male runners (age 43 ± 10.9 years and body mass index 24.5 ± 2.7 kg/m(2) ) both on the protein level in the plasma and on the messenger ribonucleic acid (mRNA) level in blood mononuclear cells (BMNC). We observed a significant increase of IL-6 (prerace 2.08 ± 0.10 ng/L and postrace 40.14 ± 24.85 ng/L, P < 0.001) and TNF-α (prerace 8.14 ± 1.38 ng/L and postrace 12.40 ± 3.15 ng/L, P < 0.001) and a decrease of leptin (prerace 1.64 ± 2.64 µg/L and postrace 0.80 ± 1.70 µg/L, P = 0.04) serum levels after the marathon race. Furthermore, TNF-α, IL-6, and leptin were expressed (mRNA level) in BMNC. However no significant differences in mRNA levels were seen before and after the run in these cells. We found an up-regulation of TNF-α and IL-6 in the plasma during vigorous exercise. This increase is not attributable to BMNC. We assume a local production in, or release from, exercised tissues.

Increased serum concentrations of adhesion molecules but not of chemokines in patients with Type 2 diabetes compared with patients with Type 1 diabetes and latent autoimmune diabetes in adult age: action LADA 5.

AIMS: Systemic concentrations of adhesion molecules and chemokines are associated with increased risk of cardiovascular complications. We compared these factors between patients with Type 2 diabetes vs. Type 1 diabetes or latent autoimmune diabetes in adults. METHODS: Serum concentrations of adhesion molecules sE-selectin, sICAM-1 and sVCAM-1, and chemokines CCL2, CCL3 and CCL4 were measured in 61 patients with latent autoimmune diabetes in adults, 90 with Type 1 diabetes, 465 with Type 2 diabetes and in 41 control subjects, using multiple regression models to adjust for possible confounders. RESULTS: Patients with Type 2 diabetes exhibited greater concentrations of adhesion molecules (P < 0.02) than those with Type 1 diabetes, latent autoimmune diabetes in adults and control subjects. These differences persisted upon adjustments for age, sex, BMI, blood pressure and diabetes duration (P < 0.04). Higher BMI positively correlated with concentrations of adhesion molecules in all subjects (P < 0.0001). Concentrations of sE-selectin positively related to diastolic (ß = 0.31) and systolic (ß = 0.28) blood pressure in the adjusted model (P < 0.04). Concentrations of the chemokines, CCL2 and CCL4, did not differ between groups, while CCL3 was higher in patients with latent autoimmune diabetes in adults and Type 1 diabetes than in those with Type 2 diabetes and control subjects (P < 0.05). CONCLUSIONS: Systemic concentrations of adhesion molecules, but not chemokines, relate to cardiovascular risk factors, but remain higher after adjustments in Type 2 diabetes, suggesting a diabetes-type specific effect without difference between latent autoimmune diabetes in adults and Type 1 diabetes, despite their dissimilar phenotype.

Comparison of the saline infusion test and the fludrocortisone suppression test for the diagnosis of primary aldosteronism.

For the diagnosis of primary aldosteronism (PA), confirmatory testing is mandatory and different function tests can be employed. There are, however, sparse data comparing the fludrocortisone suppression test (FST) and the saline infusion test (SIT). Patients with PA (n=90) or essential hypertension (n=65) were studied. They underwent one or the other test or both of them. Using the DPC Siemens aldosterone radioimmunoassay, we found that the SIT led to a stronger suppression of aldosterone than the FST. Post-test aldosterone-to-renin ratios (ARRs) and the percentage of suppression of aldosterone serum concentrations performed worse. The same results were observed in patients who underwent both FST and SIT. Some patients had divergent results in both tests. For the SIT, a lower cutoff value should be used than for the FST for the adequate identification of patients with unilateral PA. Long-term prospective studies are needed to address the question at what cutoff values patients benefit from subtype differentiation of PA. We discuss here possible explanations for divergent results obtained with both tests.

Unconditioned and conditioned effects of intranasally administered insulin vs placebo in healthy men: a randomised controlled trial.

AIMS/HYPOTHESIS: In humans, the intranasal route allows insulin to reach the brain while maintaining peripheral euglycaemia. Our aims were to examine acute (unconditioned) effects of central insulin on normal-range blood glucose and hormones in men, and to find out whether the effects of intranasal insulin can be learnt via classical conditioning. METHODS: In a randomised controlled trial, 32 healthy normal-weight men (mean age 24.2 [SEM 0.5], mean BMI 22.4 [0.3]) received a conditioned stimulus (CS) and six administrations of either soluble H-insulin 100 (20 U [0.2 ml]; group 1; n = 16) or vehicle (0.2 ml; group 2; n = 16) on day 1. The CS was the tarry smell of meta-cresol (used as a stabilising vehicle in many insulin preparations and placebos). On day 2, all participants received the CS and six administrations of placebo. Participants and experimenters were blinded to group assignment. Sixteen individuals were randomised to and analysed in each group. Participants were sequentially numbered for group allocation. The main outcome measures were blood glucose and insulin, expressed as cumulative difference-from-baseline changes. RESULTS: While maintaining euglycaemia, intranasal insulin induced an increase of peripheral insulin on day 1 (group 1, 17.78 [21.88] pmol/l vs group 2, -10.24 [9.42] pmol/l), and also on day 2 when the CS was given with placebo (group 1, 12.53 [5.57] pmol/l vs group 2, -5.51 [6.16] pmol/l). Moreover, a moderate reduction of blood glucose on day 1 (group 1, -0.54 [0.36] mmol/l vs group 2, 0.58 [0.48] mmol/l) was obtained (all p values <0.05). There were no adverse side effects. CONCLUSIONS/INTERPRETATION: The unconditioned blood glucose decrease on day 1 and the unconditioned and conditioned increases of peripheral insulin are indicative of brain-pancreas cross-talk. The conditionability of the hormonal responses reveals new applications for intranasal insulin. TRIAL REGISTRATION: DRKS00000537 http://apps.who.int/trialsearch/ FUNDING: Deutsche Forschungsgemeinschaft DFG STO 323/1-1 and 1-2.

Pro- and anti-inflammatory cytokines in latent autoimmune diabetes in adults, type 1 and type 2 diabetes patients: Action LADA 4.

AIMS/HYPOTHESIS: Systemic pro- and anti-inflammatory cytokines are associated with both type 1 and type 2 diabetes, while their role in latent autoimmune diabetes in adults (LADA) is unclear. Therefore, we compared cytokine concentrations in patients with LADA, type 1 or type 2 diabetes and healthy individuals to test the hypothesis that differences of cytokine concentrations between all groups are attributable to diabetes type and BMI. METHODS: The pro-inflammatory cytokines IL-6 and TNF-α, and the anti-inflammatory cytokines IL-1 receptor antagonist (IL-1RA) and IL-10 were measured in 90 participants with type 1 diabetes, 61 with LADA, 465 with type 2 diabetes and 41 control participants using multiple regression models adjusted for BMI, sex, age, blood pressure and diabetes duration. RESULTS: Patients with type 2 diabetes had higher concentrations of systemic IL-1RA, IL-6 and TNF-α cytokines than patients with either LADA or type 1 diabetes (p < 0.0001 for all differences). Cytokine concentrations in controls were lower than those in all diabetes types (p < 0.04). Increased BMI was positively associated with higher systemic cytokine concentrations in all diabetes types (p < 0.0001). Despite the association of cytokines with anthropometric data, differences between diabetes forms persisted also after adjusting analysis for the confounders BMI, age, sex, disease duration and blood pressure (p < 0.04). CONCLUSIONS/INTERPRETATION: Although body mass associates positively with pro- and anti-inflammatory cytokine levels, patients with type 2 diabetes have higher cytokine levels independent of the prevailing BMI. LADA and type 1 diabetes could not be distinguished by systemic cytokines.

Subclinical hypothyroidism and the prevalence of the metabolic syndrome.

There is currently controversial data regarding the prevalence of MS among SCH patients. The aim of the study was to investigate the prevalence of MS in an adult population with SCH. A cross-sectional study was conducted among 6,998 adults in China. Epidemiological information and medical data were obtained (fasting plasma glucose, triglycerides, high density lipoprotein-C, and thyroid function). The IDF criteria were applied for the diagnosis of MS. SCH was defined as TSH more than 4.5 mIU/l with normal values for FT3 and FT4. Among the 6,560 participants, 21.5% were diagnosed with MS and 8.2% suffered from SCH. MS was found in 21.3% in the euthyroidism (EUT) group and in 25.7% in the SCH group (p<0.05). However, this difference between EUT and SCH in MS prevalence was not statistically significant after adjusting for age. Of note, the prevalence of MS increased with age. The proportions of systemic hypertension, hypertriglyceridemia, impaired fasting glucose, and low HDL-C were 86.7, 59.7, 45.1 and 65.9% in EUT while the corresponding values in SCH were 89.9, 63.8, 39.9 and 72.5%, respectively (the differences, however, did not reach statistical significance). The prevalence of high BP, high TG, elevated FBP, and low HDL-C as well as the percentage of patients fulfilling the IDF criteria for the metabolic syndrome are not significantly different among SCH and EUT after adjusting for age. Therefore, subclinical hypothyroidism appears not as an independent risk factor for the metabolic syndrome in this population.

Ceruloplasmin expression in rat liver cells is attenuated by insulin: role of FoxO transcription factors.

The phosphoinositide 3'-kinase (PI3 K)/Akt pathway controls the activity of a number of proteins important in the regulation of apoptosis and cell proliferation. FoxO (forkhead box, class O) transcription factors, substrates of the Ser/Thr kinase Akt, control the expression of several target genes that are crucial to the defense against oxidative stress, the regulation of cell cycle, and apoptosis in mammalian cells. Here, expression of ceruloplasmin (CP), the major copper-containing protein in blood released by the liver, was investigated. We observed a significant downregulation of CP mRNA levels after insulin treatment in H4IIE rat hepatoma cells. The PI3K inhibitor wortmannin counteracted this insulin effect on CP mRNA levels, indicating that the PI3K/Akt cascade is involved in the regulation of CP expression. Stimulation of FoxO1 was induced in H4IIE rat hepatoma cells expressing a conditionally active FoxO1 construct, resulting in significant upregulation of CP mRNA levels. This upregulation was prevented in the presence of insulin. In parallel, mRNAs of established FoxO target genes were analyzed: like CP mRNA, selenoprotein P and glucose 6-phosphatase mRNAs were upregulated by FoxO1, which was prevented by insulin. The same effects of insulin on CP mRNA levels were detected in primary rat hepatocytes. Furthermore, CP release into cell culture media was analyzed with primary hepatocytes and found to be attenuated by insulin. In line with its insulin-mimetic effects on cultured cells, Cu (2+) imitated the effect of insulin on CP expression and caused a downregulation of CP mRNA levels in rat hepatoma cells.

Sequence homology of the diabetes-associated autoantigen glutamate decarboxylase with coxsackie B4-2C protein and heat shock protein 60 mediates no molecular mimicry of autoantibodies.

Molecular mimicry between viral antigens and host proteins was often suggested to be involved in induction of autoimmune diseases. In type 1 diabetes where pancreatic beta cells are destroyed by autoimmune phenomena, a linear sequence homology between a major autoantigen, glutamate decarboxylase (GAD), and the 2C protein of coxsackie B4 was identified. In addition, a sequence homology between GAD and the mycobacterial heat shock protein 60 was described and the suggestions were made that molecular mimicry between GAD, coxsackievirus B4-2C protein, and/or heat shock protein 60 (hsp60) may be actively involved in an autoimmune reaction towards the pancreatic beta-cells. Our group was the first to isolate human monoclonal autoantibodies to GAD (MICA 1-6) from a patient with newly diagnosed type 1 diabetes. The MICA allowed a detailed characterization of the diabetes associated self-epitopes in GAD and represent a set of GAD autoantibodies present in sera from patients with type 1 diabetes. Using deletion mutants of GAD we demonstrated that the regions of GAD covering the homology sequences to coxsackievirus B4 and to the hsp60 were absolutely required for binding of the MICA to GAD. We now designed an antibody-based analysis to ask whether molecular mimicry between GAD and coxsackie B4-2C or hsp60 is relevant in type 1 diabetes. Since part of the MICA recognize conformational epitopes, they allow to test for conformational molecular mimicry in viruses that have been incriminated in the development of type 1 diabetes. Our data reveal no crossreactivity between the diabetes associated GAD epitopes defined by the MICA and hsp60, rubellavirus, cytomegalovirus, and coxsackie B1-B6 virus antigens. Neither coxsackie B4-specific antibodies in sera from normal individuals nor GAD-positive sera from patients with type 1 diabetes indicated a crossreactivity between coxsackie B4-2C and GAD. Although the regions in GAD homologous to coxsackie B4-2C and hsp60 represented parts of GAD indispensible for binding of diabetes associated autoantibodies they did not mediate a crossreactivity of autoantibodies between GAD and these two proteins. No evidence for molecular mimicry between GAD and a whole panel of foreign antigens was detected by autoantibodies in type 1 diabetes.

Reproducibility of Elecsys anti-TSHR test results in a lot-to-lot comparison.

Most recently, a new rapid and fully-automated TSH receptor autoantibody (TRAb) assay has been established. This assay system uses the M22 human monoclonal antibody for competing against the patient's TSH receptor autoantibodies (TRAb) to be detected. The aim of our present study was to compare the reproducibility of TRAb values based on measurements with different TSH receptor preparations in a lot-to-lot comparison. For TRAb values > 2 IU/l the relative differences ranged from -9.0 to +10.0%. The mean difference was 0.28 +/- 8%. For TRAb values around the cutoff for positivity (1.75 IU/l) a higher range of relative differences from -20 up to +15% was obtained. The overall mean of differences was -0.8+/-14%. The data clearly demonstrate that the automated TRAb assay has a high stability in regard to TSH receptor preparations.

The effects of the endothelium on adrenal steroidogenesis and growth are mainly mediated by proteins other than endothelin-1.

The endothelium releases factors stimulating the adrenal cortex. It is also known that endothelin-1 (ET-1) promotes generation of cortisol and aldosterone, and proliferation of adrenocortical cells. The aim of the study was to find out whether the effect of the endothelium on adrenocortical cells is dominated by the action of ET-1. The effects of endothelial cell-conditioned medium (ECCM), obtained during growth of human umbilical cord vein endothelial cells, on aldosterone and cortisol release by cells of the adrenocortical cancer cell-line NCI-H295R and the promoter activity of steroidogenic acute-regulatory protein (StAR) were studied. The effect of ECCM on proliferation of human primary normal adrenocortical and NCI-H295R cells was also investigated. Concentration-dependent increases in cortisol release that reached 192.7 ± 62.8 in percent of basal secretion, in aldosterone release that reached 188.2 ± 52.3 in percent of basal secretion, and in proliferation after stimulation with ECCM at concentrations of 10-50% were found. ECCM significantly activated the StAR promoter 3-fold in NCI-H295R cells if the ECCM was not pretreated with pronase. These effects of the endothelium were not reversed after co-incubation with endothelin receptor antagonists and could not be mimicked by incubation with endothelin-1. In conclusion, the cultured endothelial cells secrete a protein that stimulates steroidogenesis in adrenal cells and their growth. It was also shown that the ET-1 does not mediate the effect of ECCM on the NCI-H295R cell line.

The serum sodium to urinary sodium to (serum potassium)2 to urinary potassium (SUSPPUP) ratio in patients with primary aldosteronism.

BACKGROUND: The aldosterone-to-renin ratio (ARR) is an established diagnostic tool in the screening for primary aldosteronism (PA). However, hormonal determinations are time consuming and expensive. Therefore, we studied the effectiveness of the serum sodium to urinary sodium to (serum potassium)(2) to urinary potassium (SUSPPUP) ratio in the diagnosis of PA. DESIGN: This study included 35 patients with PA, 71 patients with essential hypertension to whom this diagnosis could be excluded, 23 normal subjects without hypertension, and 22 patients with primary adrenal insufficiency. We compared the SUSPPUP ratios with the ARR in these patient groups. RESULTS: We show that the ARR distinguished PA from essential hypertension with a sensitivity of 94.2% and a specificity of 92.1% at a cutoff of 33 (ng L(-1): ng L(-1)). It correlated well with the SUSPPUP ratio. The sensitivity and specificity of SUSPPUP was 88.6% and 85.9% at a cutoff of 5.3 (mmol L(-1))(-1), respectively, and thus not as good as the ARR. CONCLUSIONS: The ARR is a good parameter in the screening for PA. The SUSPPUP ratio is a cheap and rapid tool to assess the extent of mineralocorticoid excess and, therefore, can be offered to more patients. In addition, the application of the SUSPPUP ratio can be extended to patients who suffer from other forms of mineralocorticoid hypertension (e.g. with low aldosterone levels).

Chromogranin a as potential tumour antigen in pheochromocytoma.

Chromogranin A (CgA) is a dense core vesicle-associated protein and, therefore, represents a specific marker of neuroendocrine cells and tumours including pheochromocytomas. CgA has already been investigated for its immunogenic properties. Importantly, in vitro studies demonstrated the presence of naturally occurring CgA-specific cytotoxic T cells in patients with neuroendocrine cancers. Therefore, it is worthwhile to investigate the potential role of CgA as tumour antigen in pheochromocytoma. Depending on the results of these ongoing in vitro and in vivo studies, a clinical application may arise in the near future.

Role of the novel mTOR inhibitor RAD001 (everolimus) in anaplastic thyroid cancer.

Activation of the phosphatidylinositol-3-kinase (PI3K) signaling cascade is increasingly recognized as a common feature of thyroid follicular neoplasms. Among the PI3K downstream effectors, the main kinase, directly responsible for the increased cell growth and proliferation, is called mammalian target of rapamycin (mTOR). This central kinase might be directly inhibited via rapamycin and its derivatives. The aim of the present study was to examine whether RAD001 (everolimus) can selectively suppress the proliferation of different anaplastic thyroid cancer (ATC) cells. Five different human ATC cell lines were exposed to different concentrations of RAD001. Importantly, we found a dose-dependent growth inhibition in two ATC cell lines at concentrations of 43.5 and 94.5 nM although not as intensive as within the RAD001 responding K562cell line. The other cell lines revealed a GI (50) between 168 to 234 nM. In parallel, quantitative PCR of PCNA displayed a reduced expression of PCNA within the responding cell lines, respectively. In summary, we found a good responding effect in a part of ATC cell lines, which may have a clinical impact.