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Glucocorticoid receptor gene polymorphisms in ACTH-secreting pituitary tumours

S R R Antonini1, A C Latronico, L L K Elias

  • 1Department of Paediatrics, School of Medicine of Ribeirao Preto-USP, Ribeirao Preto, Brazil.

Clinical Endocrinology
|October 23, 2002
PubMed
Abstract

Insights

Glucocorticoid receptor (GR) gene mutations are rare in ACTH-secreting pituitary tumors. While polymorphisms may play a role in tumor development, they do not appear to influence clinical presentation or outcomes.

Area of Science:

  • Endocrinology
  • Molecular Biology
  • Oncology

Background:

  • ACTH-secreting pituitary tumors disrupt the hypothalamic-pituitary axis's response to glucocorticoids.
  • The molecular basis for corticotropinoma development and glucocorticoid resistance remains unclear.

Purpose of the Study:

  • To investigate glucocorticoid receptor (GR) gene mutations and polymorphisms in corticotropinomas.
  • To explore the potential link between GR gene alterations and tissue-specific glucocorticoid resistance.

Main Methods:

  • DNA and RNA were extracted from 18 corticotropinomas.
  • The GR gene was amplified using PCR and reverse transcriptase-PCR.
  • Automated direct sequencing was employed to analyze the GR gene.

Main Results:

  • No mutations were found in the coding or exon-intron boundary regions of the GR gene.
  • Polymorphisms N363S (17%) and N766N (11%) were identified in heterozygous states.
  • Previously described polymorphisms at other sites were not observed in the tumors.

Conclusions:

  • GR gene mutations are uncommon and unlikely to cause glucocorticoid resistance in corticotropinomas.
  • GR gene polymorphisms may contribute to corticotropinoma tumorigenesis.
  • No correlation was found between GR gene polymorphisms and clinical features or surgical outcomes.

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