Searchable abstracts of presentations at key conferences in endocrinology

ea0037ep671 | Pituitary: basic and neuroendocrinology | ECE2015

G protein signalling of native somatostatin receptors 2 and 5 in pituitary cells using a fluorescence-based membrane potential assay

Gunther Thomas , Schulz Stefan

Somatostatin and dopamine receptors are the major Gi-coupled receptors in somatotrope cells that inhibit hormone secretion from the anterior pituitary. Here, we adapted a novel fluorescence-based screening assay to characterize somatostatin and dopamine receptor signaling in a time-resolved manner. This minimal-invasive technique provides a robust and reliable read out for ligand-induced receptor activation in permanent cell lines and primary pituitary culture. The ...

ea0037gp.09.03 | Nuclear receptors and signalling | ECE2015

Agonist-selective phosphorylation of the human sst3 somatostatin receptor determined by phosphosite-specific antibodies

Lehmann Andreas , Schulz Stefan , Gunther Thomas

The human somatostatin receptor 3 (hsst3) is expressed in about 50% of all neuroendocrine tumours. The sst3 receptor is unique among somatostatin receptors which can initiate apoptosis of tumour cells through activation of the tumour suppressor p53. Furthermore, treatment of the sst3 receptor with somatostatin or stable somatostatin analogues such as octreotide or pasireotide can inhibited tumour cell proliferation. However, at present little is known about the agonist-induced...

ea0032oc1.5 | Pituitary & Molecular Endocrinology | ECE2013

Differential effect of octreotide treatment on expression of sstr2a, 3 and 5 in somatotroph adenomas

Heck Ansgar , Casar-Borota Olivera , Ramm-Pettersen Jon , Schulz Stefan , Bollerslev Jens

Introduction: The effect of conventional somatostatin agonists (SA) on somatotroph pituitary adenomas is primarily mediated by somatostatin receptors (sstr) subtype 2. Sstr expression has been proposed as a prognostic marker for response to medical therapy. Earlier studies have shown lower sstr2a expression in SA treated adenomas, but selection bias could not be excluded.Objective: To assess the effect of SA on the immunohistochemical expression of sstr2...

ea0047oc15 | Spotlight on Neuroendocrine tumours | Theranostics2016

Evaluation of somatostatin, CXCR4 chemokine and endothelin a receptor expression in a large series of paragangliomas

Kaemmerer Daniel , Saenger Joerg , Arsenic Ruza , D'Haese Jan G. , Neumann Jens , Singh Aviral , Baum Richard P. , Schulz Stefan , Lupp Amelie

Background: Paragangliomas are predominantly benign tumors, but in some cases invasive growth and also metastasis is observed. Given the limited number of nonsurgical treatment options, novel target structures for diagnostics and therapy of this tumor entity are urgently needed.Aims: In the present study the expression of the five somatostatin receptor (SSTR) subtypes as well as of the chemokine receptor CXCR4 and of the endothelin receptor A (ETA) was e...

ea0081p169 | Pituitary and Neuroendocrinology | ECE2022

Identification of a novel SSTR3 full agonist and its activity in non-functioning pituitary adenoma model

Modena Daniela , Luisa Moras Maria , Sandrone Giovanni , Stevenazzi Andrea , Vergani Barbara , Dasgupta Pooja , Kliewer Andrea , Gulde Sebastian , Schillmaier Mathias , Luque Raul M. , Schulz Stefan , Pellegata Natalia , Steinkuhler Christian

Non-functioning pituitary adenomas (NFPAs), mainly gonadotroph pituitary adenomas (GPAs), are the second most common type of PAs. Given the lack of symptoms secondary to hormone hypersecretion, NFPAs are often diagnosed when they cause mass effects. At this stage they are invasive (50% of cases), they cannot be completely resected and often recur. Despite their frequency, no standard of care drug treatment currently exists for these tumors. SSAs (somatostatin agonists) like oc...