Novel molecular aspects of pituitary adenomas.

Ghrelin stimulates while somatostatin inhibits GH release and they thus serve as functional antagonists. We have compared their effects on cell proliferation. Ghrelin stimulates while somatostatin inhibits cell proliferation in most tissues and cell lines. Here we show that ghrelin and desoctanoyl g...

Full description

Bibliographic Details
Main Authors: Hubina, E, Ruscica, M, Nanzer, A, Czirják, S, Góth, M, Grossman, AB, Korbonits, M
Format: Journal article
Language:English
Published: 2005
_version_ 1797075961281249280
author Hubina, E
Ruscica, M
Nanzer, A
Czirják, S
Góth, M
Grossman, AB
Korbonits, M
author_facet Hubina, E
Ruscica, M
Nanzer, A
Czirják, S
Góth, M
Grossman, AB
Korbonits, M
author_sort Hubina, E
collection OXFORD
description Ghrelin stimulates while somatostatin inhibits GH release and they thus serve as functional antagonists. We have compared their effects on cell proliferation. Ghrelin stimulates while somatostatin inhibits cell proliferation in most tissues and cell lines. Here we show that ghrelin and desoctanoyl ghrelin stimulate cell proliferation in rat pituitary cell line (GH3), and these effects could be inhibited with mitogen-activated protein kinase (MAPK), tyrosine kinase and protein kinase C inhibitors. Somatostatin and its analogs negatively regulate the growth of pituitary cells, and we now show that they inhibit MAPK activation. We hypothesised that one of the mechanisms involved in the somatostatin effect is a stimulation of cell cycle inhibitor p27, as pituitary adenomas have decreased p27 peptide content. Both octreotide and a new somatostatin analog SOM230 treatment resulted in an upregulation of p27 protein levels in human somatotrophinoma cells. In summary, we suggest that ghrelin and somatostatin have opposite effects on somatotroph cells not just at the level of GH release but also in terms of cell proliferation. Ghrelin may play a role in pituitary tumorigenesis via an autocrine/paracrine pathway. Our results also suggest that the antiproliferative effect of somatostatin analogs octreotide and SOM230 involve the up-regulation of p27 and down-regulation of the MAPK pathway in human somatotrophinomas.
first_indexed 2024-03-06T23:57:33Z
format Journal article
id oxford-uuid:74c418b4-2a13-45b8-b7f8-b55844ef8db4
institution University of Oxford
language English
last_indexed 2024-03-06T23:57:33Z
publishDate 2005
record_format dspace
spelling oxford-uuid:74c418b4-2a13-45b8-b7f8-b55844ef8db42022-03-26T20:05:05ZNovel molecular aspects of pituitary adenomas.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:74c418b4-2a13-45b8-b7f8-b55844ef8db4EnglishSymplectic Elements at Oxford2005Hubina, ERuscica, MNanzer, ACzirják, SGóth, MGrossman, ABKorbonits, MGhrelin stimulates while somatostatin inhibits GH release and they thus serve as functional antagonists. We have compared their effects on cell proliferation. Ghrelin stimulates while somatostatin inhibits cell proliferation in most tissues and cell lines. Here we show that ghrelin and desoctanoyl ghrelin stimulate cell proliferation in rat pituitary cell line (GH3), and these effects could be inhibited with mitogen-activated protein kinase (MAPK), tyrosine kinase and protein kinase C inhibitors. Somatostatin and its analogs negatively regulate the growth of pituitary cells, and we now show that they inhibit MAPK activation. We hypothesised that one of the mechanisms involved in the somatostatin effect is a stimulation of cell cycle inhibitor p27, as pituitary adenomas have decreased p27 peptide content. Both octreotide and a new somatostatin analog SOM230 treatment resulted in an upregulation of p27 protein levels in human somatotrophinoma cells. In summary, we suggest that ghrelin and somatostatin have opposite effects on somatotroph cells not just at the level of GH release but also in terms of cell proliferation. Ghrelin may play a role in pituitary tumorigenesis via an autocrine/paracrine pathway. Our results also suggest that the antiproliferative effect of somatostatin analogs octreotide and SOM230 involve the up-regulation of p27 and down-regulation of the MAPK pathway in human somatotrophinomas.
spellingShingle Hubina, E
Ruscica, M
Nanzer, A
Czirják, S
Góth, M
Grossman, AB
Korbonits, M
Novel molecular aspects of pituitary adenomas.
title Novel molecular aspects of pituitary adenomas.
title_full Novel molecular aspects of pituitary adenomas.
title_fullStr Novel molecular aspects of pituitary adenomas.
title_full_unstemmed Novel molecular aspects of pituitary adenomas.
title_short Novel molecular aspects of pituitary adenomas.
title_sort novel molecular aspects of pituitary adenomas
work_keys_str_mv AT hubinae novelmolecularaspectsofpituitaryadenomas
AT ruscicam novelmolecularaspectsofpituitaryadenomas
AT nanzera novelmolecularaspectsofpituitaryadenomas
AT czirjaks novelmolecularaspectsofpituitaryadenomas
AT gothm novelmolecularaspectsofpituitaryadenomas
AT grossmanab novelmolecularaspectsofpituitaryadenomas
AT korbonitsm novelmolecularaspectsofpituitaryadenomas