0000000000215114
AUTHOR
Christian Fottner
Identification and prevention of genotyping errors caused by G-quadruplex- and i-motif-like sequences.
Abstract Background: Reliable PCR amplification of DNA fragments is the prerequisite for most genetic assays. We investigated the impact of G-quadruplex– or i-motif–like sequences on the reliability of PCR-based genetic analyses. Methods: We found the sequence context of a common intronic polymorphism in the MEN1 gene (multiple endocrine neoplasia I) to be the cause of systematic genotyping errors by inducing preferential amplification of one allelic variant [allele dropout (ADO)]. Bioinformatic analyses and pyrosequencing-based allele quantification enabled the identification of the underlying DNA structures. Results: We showed that G-quadruplex– or i-motif–like sequences can reproducibly …
Elevated serum levels of IGF-binding protein 2 in patients with non-seminomatous germ cell cancer: correlation with tumor markers alpha-fetoprotein and human chorionic gonadotropin.
Background/aimsAlterations of the IGF system have been described in several different types of cancer. However, no information is available about the role of the IGF system in patients with non-seminomatous germ cell cancer.MethodsFree IGF-I, IGF-II, acid-labile subunit, and IGF-binding proteins (IGFBPs) 1–4 were analyzed by specific RIAs in 32 patients with untreated non-seminomas and compared with IGFBP levels of 38 healthy controls. Serum IGFBPs were analyzed by western ligand blotting (WLB) and immunoblotting. In 16 patients, IGFBP profiles were measured before, during, and after treatment.ResultsIn patients with testicular cancer, IGF-II levels were on average 1.44-fold higher than in …
The Effects of Self-Control on Glucose Utilization in a Hyperinsulinemic Euglycemic Glucose Clamp
Abstract. Background. The glucose hypothesis of self-control posits that acts of self-control may draw upon glucose as a source of energy, leading to a decrease in blood glucose levels after exerting self-control, mirroring the temporary depletion of self-control, but supporting evidence is mixed and inconclusive. This might partly be due to using methods that are not suitable to reliably quantify glucose utilization. Aims. We aimed at examining whether self-control exertion leads to an increase in glucose utilization. Method. In a sample of N = 30 healthy participants (50% women, age 26.5 ± 3.5 years) we combined a hyperinsulinemic euglycemic glucose clamp (a well-established and validate…
ASCO-Update 2015 – Neuigkeiten vom 51. Meeting der American Society of Clinical Oncology/ASCO 2015
The field of gastrointestinal oncology is rapidly developing, on the one hand through the identification of novel molecular targets and therapeutic principles, on the other hand through the establishment and improvement of multidisciplinary treatment strategies. The following manuscript summarizes the most important trial results of the ASCO Meeting 2015 for gastrointestinal cancers. Besides trials on perioperative treatment of esophageal-, pancreatic- and colon cancer, we will present impressive data on new therapeutic strategies such as immunotherapy in gastric-, liver and microsatellite instable colorectal cancer. The trials will be put into context by the authors.
Interdisciplinary treatment of diabetic foot wounds in the elderly : Low risk of amputations and mortality and good chance of being mobile with good quality of life
Aims: A major proportion of patients with diabetic foot syndrome are older than 65 years. Little is known about outcomes of these elderly patients. Methods: We analysed 245 treatment cases in an observational single-centre study for comorbidities and outcomes over a 6-month period. Results: In all, 122 patients had peripheral arterial disease which was significantly increasing with age ( n = 245, df = 1, χ2 = 23.06, p ⩽ 0.0001). Increasing age correlated positively with decreasing rate of revascularisations ( n = 122, df = 1, χ2 = 4.23, p = 0.039). In total, 23 (9.3%) patients died in the observation period. In-hospital mortality was 2.8%, percentage of major amputations 2.8%. In the invasi…
Magnetic separation of encapsulated islet cells labeled with superparamagnetic iron oxide nano particles.
Islet cell transplantation is a promising option for the restoration of normal glucose homeostasis in patients with type 1 diabetes. Because graft volume is a crucial issue in islet transplantations for patients with diabetes, we evaluated a new method for increasing functional tissue yield in xenogeneic grafts of encapsulated islets. Islets were labeled with three different superparamagnetic iron oxide nano particles (SPIONs; dextran-coated SPION, siloxane-coated SPION, and heparin-coated SPION). Magnetic separation was performed to separate encapsulated islets from the empty capsules, and cell viability and function were tested. Islets labeled with 1000 μg Fe/ml dextran-coated SPIONs expe…
Peptide Receptor Radionuclide Therapy Combined With Chemotherapy in Patients With Neuroendocrine Tumors
Combinations of therapies may enhance therapeutic effects without significantly increasing the incidence of adverse events. However, there are few data regarding survival after concomitant chemotherapy and peptide receptor radionuclide therapy (PRRT) with [Lu]Lu-octreotate in patients with neuroendocrine tumors (NETs). Thus, we explored the outcome of this combination of therapies.Fifteen patients with somatostatin receptor-positive, rapidly progressive G2/G3 NETs during chemotherapy or PRRT alone from 2 German cancer centers were included in the retrospective analysis. The patients received a combination of PRRT and chemotherapy with temozolomide (n = 3) or temozolomide plus capecitabine (…
In vivo molecular and morphological imaging by real time confocal mini-microscopy
We evaluated a newly developed miniaturized confocal laser microscopy probe for real-time in vivo molecular and morphological imaging of normal, inflammatory, and malignant tissue in rodents. In the rigid mini-microscopy probe (diameter 7 mm), a single line laser delivers an excitation wavelength of 488 nm. Optical slice thickness is 7 μm, lateral resolution 0.7 μm. The range of the z-axis is 0 - 250 μm below the tissue surface. Organ systems were examined in vivo in rodent models of human diseases. FITC-labeled Lycopersion esculentum lectin was injected or selected cell populations stained for molecular targeting. Morphological imaging was performed using fluorescein sodium, FITC-labeled d…
Somatostatin-producing neuroendocrine tumors of the duodenum and pancreas: incidence, types, biological behavior, association with inherited syndromes, and functional activity
Somatostatin-producing neuroendocrine tumors (SOM-NETs) of the duodenum and pancreas appear to be heterogeneous. To determine their clinicopathological profiles, respective data were analyzed on a series of 82 duodenal and 541 pancreatic NETs. In addition, the clinical records of 821 patients with duodenal or pancreatic NETs were reviewed for evidence of a somatostatinoma syndrome. Predominant or exclusive expression of somatostatin was found in 21 (26%) duodenal and 21 (4%) pancreatic NETs. They were classified as sporadic (n=31) or neurofibromatosis type 1 (NF1)-associated duodenal NETs (n=3), gangliocytic paragangliomas (GCPGs; n=6), or poorly differentiated neuroendocrine carcinomas (pd…
The Divergent Effect of Insulin-Like Growth Factor Binding Protein (IGFBP) - 1 on IGF-induced Steroidogenesis in Bovine Adrenocortical Cells is not due to its Phosphorylation Status
In previous studies we have shown that insulin-like growth factor (IGF)-II stimulates basal as well as ACTH-induced cortisol secretion from bovine adrenocortical cells more potently than IGF-I. The steroidogenic effect of both, IGF-I and IGF-II, is mediated through the IGF-I receptor and modified by locally produced IGF binding proteins. Further studies demonstrate that bovine adrenocortical cells do synthesize IGFBP-1 to -4 and that their secretion is regulated differentially by IGFs and ACTH. Since IGFBP-1 selectively is induced 3- to 4- fold by ACTH, the aim of the following studies was to evaluate the effect of IGFBP-1 on IGF-induced cortisol secretion from bovine adrenocortical cells i…
Head and neck paragangliomas: Report of 175 patients (1989-2010)
Attention of the otorhinolaryngologist needs to be drawn to the versatile aspects of head and neck paragangliomas (PGLs).This study is a retrospective, nonrandomized clinical study of all 175 individuals with PGLs treated in our department between 1989 and 2010. A genetic analysis was performed on 86 patients.The 175 patients presented 224 head and neck PGLs as well as 2 thyroid papillary carcinomas. Genetic analysis resulted in 1 patient positive for a von Hippel-Lindau (VHL) gene mutation and 34 for succinate dehydrogenase (SDH) gene mutations (22 SDHD, 7 SDHC, and 5 SDHB), 12 of the latter carrying a novel mutation. Thirty-three patients (18.9%) had multiple PGLs and 11 patients (6.3%) h…
Peptide receptor radionuclide therapy combined with chemotherapy
Multiple modes of cell death in neuroendocrine tumors induced by artesunate.
Abstract Background The paucity of effective treatment in neuroendocrine tumors (NETs) encouraged us to investigate the therapeutic value of artesunate (ART) promised by its inhibitory effect against various tumors and broad safety profile. Methods We evaluated the impact of ART on three NET cell lines, BON-1, QGP-1 and NCI-H727 on cellular and molecular levels. Results Our results showed that ART induced endoplasmic reticulum (ER) stress through phosphorylation of eIF2α, which further gave rise to autophagy in all three NET cell lines. Specifically, apoptosis and ferroptosis were also observed in BON-1 cells, which made BON-1 cell line more vulnerable upon ART treatment. The different sens…
Molecular imaging of gastroenteropancreatic neuroendocrine tumors.
Somatostatin-receptor scintigraphy has become an obligatory molecular imaging method in the management of patients with neuroendocrine tumors when metastatic disease is suspected. Using positron emission tomography and new somatostatin analogues, sensitivity of somatostatin receptor imaging has further increased. With a combination of morphologic imaging methods, such as hybrid imaging by PET/CT, this method represents the method of choice in many centers and efforts are under way to translate somatostatin receptor imaging onto a cellular level by endoscopic confocal microscopy. Other clinically relevant functional pathways in neuroendocrine tumors that are accessible by PET imaging are glu…
In Vivo Molecular Imaging of Somatostatin Receptors in Pancreatic Islet Cells and Neuroendocrine Tumors by Miniaturized Confocal Laser-Scanning Fluorescence Microscopy
The aim of the study was to evaluate real time in vivo molecular imaging of somatostatin receptors (sstrs) using a handheld miniaturized confocal laser scan microscope (CLM) in conjunction with fluorescein-labeled octreotate (OcF) in healthy mice and murine models of neuroendocrine tumors. For CLM a small rigid probe (diameter 7 mm) with an integrated single line laser (488 nm) was used (optical slice thickness 7 μm; lateral resolution 0.7 μm). OcF was synthesized via Fmoc solid-phase peptide synthesis and purified by HPLC showing high-affinity binding to the sstr2 (IC50 6.2 nmol). For in vitro evaluation, rat and human pancreatic cancer cells were used and characterized with respect to its…
Malignant paraganglioma caused by a novel germline mutation of the succinate dehydrogenase D-gene--a case report.
Background Paragangliomas of the head and neck are rare, mostly benign tumors. Approximately 10% to 15% of paragangliomas are caused by mutations in the succinate dehydrogenase (SDH) genes B, C, or D. These are often multifocal as part of paraganglioma syndromes and hormone secreting, and malignant particularly associated with mutations in SDHB. Methods and Results A 29-year-old man was seen with recurrent paraganglioma. The patient's father reportedly suffered from bilateral carotid body tumors. Imaging studies showed metastases in both lungs and the liver. There was no increased hormone production by the tumor. Sequence analysis of the SDH genes revealed a novel C to T nonsense mutation i…
Phenotypic characterisation of pro-inflammatory monocytes and dendritic cells in peripheral arterial disease
SummaryAtherosclerosis is a chronic inflammatory process involving antigen-presenting cells like monocytes and dendritic cells (DC). The aim of this study was to perform a phenotypic characterisation of these cell types in patients with different degrees of peripheral arterial disease (PAD). Sixty patients with PAD [N= 30 intermittent claudication (IC), N= 30 critical limb ischemia (CLI)] and 30 controls were included. Peripheral blood leucocytes were analysed from peripheral blood by flow cytometry using different gating strategies to directly identify and analyse monocytes, myeloid DC, (mDC) and plasmacytoid DC (pDC). PAD patients showed a significantly higher proportion of proinflammator…
Overexpression of the insulin-like growth factor I receptor in human pheochromocytomas.
In order to determine the role of the IGF-I receptor (IGF-IR) in human pheochromocytomas we have compared the expression of the IGF-IR in normal tissues and in pheochromocytomas with regard to the IGF-IR mRNA levels and ligand binding. By semiquantitative reverse transcription polymerase chain reaction (RT-PCR), the mRNA of the IGF-IR could be detected in all samples of normal adrenomedullary cells (n=13) and pheochromocytomas (n=16). However, pheochromocytomas exhibited 2.8-fold higher mean IGF-IR mRNA levels than normal adrenomedullary cells (2.8±0.5×105 molecules/μg RNA vs 7.8±1.2×105 molecules/μg RNA; P < 0.001). This overexpression of the IGF-IR in pheochromocytomas could be confirm…
6-18F-Fluoro-l-Dihydroxyphenylalanine Positron Emission Tomography Is Superior to123I-Metaiodobenzyl-Guanidine Scintigraphy in the Detection of Extraadrenal and Hereditary Pheochromocytomas and Paragangliomas: Correlation with Vesicular Monoamine Transporter Expression
Context: Pheochromocytomas (PHEOs) and paragangliomas (PGLs) may be better detected by 18F-fluorodihydroxyphenylalanine-positron emission tomography (FDOPA-PET) than 123I-metaiodobenzyl-guanidine (123-I-MIBG) scintigraphy. Objective: The objective of the study was to correlate functional imaging results with immunohistochemical, molecular-genetic, and biochemical findings. Design and Setting: Thirty consecutive patients with suspected PHEO/PGL presenting at a tertiary referral centre were investigated in a prospective study. Patients: Twenty-five patients had confirmed PHEO/PGL. Thirteen of 25 patients had a hereditary PHEO/PGL syndrome (two multiple endocrine neoplasia II, six succinate de…
Critical limb ischaemia is characterised by an increased production of whole blood reactive oxygen species and expression of TREM-1 on neutrophils
Atherosclerosis is a chronic inflammatory process involving polymorphonuclear neutrophils (PMN) and formation of reactive oxygen species (ROS). The aim of the present study was to investigate the phenotype of inflammatory cells in regard to the expression of triggering receptor expressed on myeloid cells (TREM)-1 and its soluble form (sTREM-1) as well as its relationship with oxidative stress in peripheral artery disease (PAD) patients.In total 90 patients with PAD (N = 30 intermittent claudication (IC)300 m absolute walking distance, N = 30 IC300 m absolute walking distance, N = 30 critical limb ischaemia (CLI)) and 30 control persons were included. ROS formation was measured at basal or s…
A phase II, open label, multicenter trial of avelumab in patients with advanced, metastatic high-grade neuroendocrine carcinomas NEC G3 (WHO 2010) progressive after first-line chemotherapy (AVENEC).
4103 Background: High grade Neuroendocrine Neoplasias (NEN) are rare tumors with a poor prognosis and no established second line therapy when progressive after first line platinum-based chemotherapy resulting in a median overall survival (OS) of 5 months. This study aims to evaluate the efficacy and safety of the anti-programmed death ligand-1 (PD-L1) antibody Avelumab in patients (pts) with NEN G3 progressing after first-line chemotherapy. Methods: In a multicenter, national, single-arm, open-label, phase II trial the efficacy and safety of Avelumab was evaluated in patients with metastatic progressive Neuroendocrine Carcinomas (NEC G3) according to WHO 2010, excluding Merkel cell carcino…
PD-L1 Expression and Immune Cell Infiltration in Gastroenteropancreatic (GEP) and Non-GEP Neuroendocrine Neoplasms With High Proliferative Activity
The potential of neuroendocrine neoplasms (NEN) to respond to checkpoint inhibitors is largely unknown and full of great expectations. Immunohistochemical (IHC) studies of programmed cell death ligand 1 (PD-L1) expression in the tumor microenvironment and its implications in predicting the response to checkpoint inhibition is a very active subject. Currently, the combined analysis of PD-L1 expression and tumor-associated immune cell (TAIC) infiltration is considered the best predictive marker of therapeutic response. Here we investigated the expression of PD-L1 on tumor cells (TC) and tumor-infiltrating immune cells (IC) by IHC in 68 NEN samples with a high proliferation rate (Ki-67 >20%…