The somatostatin receptor subtype 5 in neuroendocrine tumours.
BACKGROUND
In recent years, scientific work has been intensified to unravel new (patho-) physiological insights, particularly regarding the functional role of somatostatin (SRIF) receptor subtype 5 (sst) and the development of novel sst(5)-targeted SRIF analogues, in order to broaden medical therapeutic opportunities in patients suffering from neuroendocrine diseases.


METHODS
The scope of this review is primarily focused upon recent insights in sst(5)-receptor physiology, novel sst(5)-targeted treatment options predominantly directed towards pituitary adenomas, and gastroenteropancreatic neuroendocrine tumours.


RESULTS
An understanding of the potential that novel sst(5)-targeted SRIF analogues might have in the medical treatment of Cushing's disease and acromegaly, as demonstrated by translational research, based on pathophysiological data combined with results from clinical trials.


CONCLUSIONS
The role of targeting sst(5) in gastroenteropancreatic neuroendocrine tumours remains to be established. The sst(5) subtype might function as sst(2) modulator in terms of receptor internalization and desensitization, and seems less important compared with sst(2)-preferring SRIF analogues in the regulation of human insulin secretion by the pancreas. Finally, absence of sst(5) in corticotroph adenomas could be related to tumour aggressiveness in Cushing's disease.
Department of Internal Medicine, Division of Endocrinology, Room Ee530b, Erasmus MC, Dr Molewaterplein 50, 3015 GE Rotterdam, The Netherlands. l.hofland@erasmusmc.nl
Joost
J
van der Hoek
Steven W J
SW
Lamberts
Leo J
LJ
Hofland
D000236:Adenoma / Q000188:drug therapy / Q000503:physiopathology; D000818:Animals; D016503:Drug Delivery Systems; D015195:Drug Design; D005770:Gastrointestinal Neoplasms / Q000188:drug therapy / Q000503:physiopathology; D006801:Humans; D018358:Neuroendocrine Tumors / Q000188:drug therapy* / Q000503:physiopathology; D010190:Pancreatic Neoplasms / Q000188:drug therapy / Q000503:physiopathology; D010911:Pituitary Neoplasms / Q000188:drug therapy / Q000503:physiopathology; D017481:Receptors, Somatostatin / Q000187:drug effects* / Q000378:metabolism
D017481:Receptors, Somatostatin; C094573:somatostatin receptor 5