somatostatin analoges labeled with different radionuclides are able used for imaging and treatment of somatostatin receptor positive tumors. in this study tyr³-octreotide protected at lysine as an analoge of somatostatin was conjugated with bifunctional chelating agent 6-boc-hydrazinopyridine-3-carboxylic acid (boc-hynic) and after deprotecting of conjugate, purification was performed with prep...

Introduction: The present study was aimed to assess the diagnostic performance of the two imaging methods of 131I-metaiodobenzylguanidine (131I-MIBG) and 99mTc-hydrazinonicotinyl-Tyr3-Octreotide (99mTc-HYNIC-TOC) in diagnosis and localization of pheochromocytoma and neuroblastoma. Methods: This study ...

A new treatment modality for inoperable or metastasized gastroenteropancreatic tumors is the use of radiolabeled somatostatin analogs. Initial studies with high doses of [(111)In-diethylenetriaminepentaacetic acid (DTPA)(0)]octreotide in patients with metastasized neuroendocrine tumors were encouraging, although partial remissions were uncommon. Another radiolabeled somatostatin analog that is ...

Somatostatin analoges labeled with different radionuclides are able used for imaging and treatment of somatostatin receptor positive tumors. In this study Tyr³-Octreotide protected at lysine as an analoge of somatostatin was conjugated with bifunctional chelating agent 6-BOC-hydrazinopyridine-3-carboxylic acid (BOC-HYNIC) and after deprotecting of conjugate, purification was performed wit...

Somatostatin receptor imaging (SRI) with [(111)In-DTPA(0)]octreotide has proven its role in the diagnosis and staging of gastroenteropancreatic neuroendocrine tumors (GEPNETs). Newer radiolabeled somatostatin analogs which can be used in positron emission tomography (PET) imaging, and which have a higher affinity for the somatostatin receptor, especially receptor subtype-2, have been developed....

Agonist-induced internalization of somatostatin receptors (ssts) determines subsequent cellular responsiveness to peptide agonists and influences sst receptor scintigraphy. To investigate sst2A trafficking, rat sst2A tagged with epitope was expressed in human embryonic kidney cells and tracked by antibody labeling. Confocal microscopical analysis revealed that stimulation with sst and octreotid...

One of the main objectives of our current work is the development of new somatostatin analogs that would retain the general characteristics of [Tyr(3)]octreotate (Tate) while showing potential for clinical application. In this respect, study of their interaction with the sst(2) is crucial in providing preliminary structure-activity relationships data. In the present work we report on the synthe...

Purpose. In the mouse model of oxygen-induced retinopathy (OIR), somatostatin-14 (SRIF) acting at the SRIF receptor subtype 2 (sst(2)) inhibits angiogenic responses to hypoxia through a downregulation of vascular endothelial growth factor. Information about where SRIF-sst(2) interactions take place is lacking, and downstream effectors mediating SRIF-sst(2) antiangiogenic actions are unknown. Me...

UNLABELLED A promising application of radiolabeled somatostatin analogs is peptide receptor-targeted radionuclide therapy of somatostatin receptor-expressing tumors. A suitable radionuclide is (90)Y, which emits high-energy beta-particles with a pathlength of several millimeters in tissue, making it especially promising for treatment of large tumors. METHODS We investigated the radiotherapeut...

Neuroendocrine tumours (NETs) constitute a heterogeneous group of tumours that frequently express cell membrane-specific peptide receptors, such as somatostatin receptors (SSTRs), and of which gastroenteropancreatic (GEP), carcinoid and pancreatic islet cell tumours exhibit the highest expression of SSTRs. Radiolabelled receptor-binding somatostatin analogues (octreotide and lanreotide) act as ...