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Updated: Aug 12, 2026
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Three-dimensional Alginate-bead Culture of Human Pituitary Adenoma Cells
Published on: February 18, 2016
Growth hormone receptor expression and function in pituitary adenomas
Lene R Clausen1, Mikkel T Kristiansen, Lars M Rasmussen
1Medical Department M (Endocrinology and Diabetes) and Institute of Experimental Clinical Research, Aarhus University Hospital, Aarhus, Denmark.
Clinical Endocrinology
|April 24, 2004
Summary
Growth hormone (GH) receptors are present in nonfunctioning pituitary adenomas (NFPAs), but GH and IGF-I do not consistently stimulate tumor cell proliferation or hormone secretion in vitro.
Area of Science:
- Endocrinology
- Oncology
- Molecular Biology
Background:
- Hypopituitarism and GH deficiency are common in patients with nonfunctioning pituitary adenomas (NFPAs).
- Factors influencing NFPA growth, especially residual tumor tissue, are not fully understood.
- The impact of GH and IGF-I on human pituitary cell proliferation remains largely unreported.
Purpose of the Study:
- To investigate GH receptor (GHR) expression and signaling in NFPA tissue.
- To determine the effect of GH and IGF-I on NFPA cell proliferation and hormone secretion in vitro.
Main Methods:
- GHR expression analyzed via RT-PCR in 14 NFPA samples.
- GHR immunostaining performed on six tumors.
- STAT5 phosphorylation assessed by Western blot.
- Cell proliferation measured by [H3]-thymidine incorporation.
- Glycoprotein hormone production analyzed by RIA.
Main Results:
- All investigated adenomas expressed GHR, but STAT5 phosphorylation was not detected.
- GH and IGF-I did not significantly stimulate overall cell proliferation in vitro.
- GH did not significantly affect glycoprotein hormone secretion in vitro.
Conclusions:
- GH receptors are expressed in human pituitary adenoma cells, but their functional significance is unclear.
- GH and IGF-I do not consistently affect the proliferation of cultured pituitary adenoma cells.
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