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Aberrant receptor-mediated Cushing's syndrome

Xavier Bertagna1, Lionel Groussin, Jean-Pierre Luton

  • 1Service des Maladies Endocriniennes et Métaboliques, Hôspital Cochin, Paris, France. xavier.bertagna@cch.ap-hop-paris.fr

Hormone Research
|March 18, 2003
PubMed

Insights

Aberrant G-protein-coupled receptor expression in endocrine tumors, like Cushing's syndrome, drives abnormal cortisol production. This includes food-dependent hypercortisolism linked to specific receptor alterations.

Area of Science:

  • Endocrinology
  • Molecular Biology
  • Oncology

Background:

  • G-protein-coupled receptors (GPCRs) and G-proteins are crucial for intracellular signaling in endocrine tissues.
  • Alterations in these pathways are implicated in the development of endocrine tumors.
  • Aberrant receptor expression is a known factor in adrenal adenomas and ACTH-independent macronodular bilateral adrenal hyperplasia.

Purpose of the Study:

  • To investigate the role of aberrant G-protein-coupled receptor expression in endocrine tumors, particularly Cushing's syndrome.
  • To identify specific receptors involved in abnormal cortisol production.
  • To understand the correlation between receptor expression levels and clinical manifestations.

Main Methods:

  • Analysis of G-protein-coupled receptor expression in endocrine tumor tissues.
  • Investigating the signaling pathways regulated by these receptors.
  • Correlating receptor expression levels with hormone production and clinical data.

Main Results:

  • Documented multiple alterations of GPCRs and G-proteins in endocrine tumors.
  • Observed aberrant expression of membrane receptors, including GPCRs, in adrenal adenomas and ACTH-independent macronodular bilateral adrenal hyperplasia.
  • Identified aberrant gastric inhibitory polypeptide receptor expression as a cause of food-dependent hypercortisolism.
  • Reported aberrant expression of luteinizing hormone, 2-adrenergic, and interleukin receptors.
  • Found that vasopressin V1a receptor expression levels correlate with ACTH-independent cortisol response to vasopressin.

Conclusions:

  • Aberrant G-protein-coupled receptor expression is a significant mechanism in endocrine tumorigenesis and hormone dysregulation.
  • Specific receptor alterations, such as the gastric inhibitory polypeptide receptor, lead to distinct clinical syndromes like food-dependent hypercortisolism.
  • Further research into these aberrant receptors may reveal novel therapeutic targets for endocrine disorders.

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