title: Adrenocorticotropic hormone-independent Cushing's syndrome.
abstract: OBJECTIVE
  Endogenous Cushing's syndrome is adrenocorticotropic hormone (or corticotropin)-independent in 15-20% of cases. Primary Cushing's syndrome is most often secondary to adrenocortical adenomas or carcinomas, and more rarely to bilateral adrenal hyperplasias. Corticotropin-independent cortisol-producing hyperplasia is caused by micronodular diseases, including primary pigmented nodular adrenocortical disease and nonpigmented micronodular hyperplasia and adrenocorticotropic hormone-independent macronodular adrenal hyperplasia. Primary pigmented nodular adrenocortical disease can be found either alone or in the context of Carney complex, a multiple endocrine neoplasia syndrome.
  
  
  RESULTS
  In recent years, the pathophysiology of adrenocortical tumors and hyperplasias became better understood following the identification of genes responsible for syndromes associated with corticotropin-independent Cushing's syndrome and the demonstration of aberrant expression and function of various hormone receptors in adrenocortical adenomas and adrenocorticotropic hormone-independent macronodular adrenal hyperplasia. This article reviews findings on the molecular and genetic aspects of corticotropin-independent Cushing's syndrome including recent gene expression profiling studies of adrenocortical tumors and hyperplasias and animal models that provided clues on the pathogenesis of primary Cushing's syndrome.
  
  
  CONCLUSIONS
  A better understanding of molecular mechanisms involved in adrenocortical tumors and hyperplasias may lead to improved diagnostic and prognostic markers and treatment strategies to assist clinicians in the management of corticotropin-independent Cushing's syndrome.
authors.affiliation: Division of Endocrinology, Department of Medicine and Research Center, Centre Hospitalier de l'Université de Montréal (CHUM), Montréal, Québec, Canada. isabelle.bourdeau@umontreal.ca
authors.forename: Isabelle
authors.initials: I
authors.lastname: Bourdeau
authors.forename: Antoine
authors.initials: A
authors.lastname: Lampron
authors.forename: Marcia Helena Soares
authors.initials: MH
authors.lastname: Costa
authors.forename: Mimi
authors.initials: M
authors.lastname: Tadjine
authors.forename: André
authors.initials: A
authors.lastname: Lacroix
mesh_terms: D000303:Adrenal Cortex Diseases / Q000150:complications* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000306:Adrenal Cortex Neoplasms / Q000150:complications* / Q000235:genetics / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000818:Animals; D003480:Cushing Syndrome / Q000209:etiology*; D020869:Gene Expression Profiling; D006801:Humans; D006965:Hyperplasia
chemical_list: D000324:Adrenocorticotropic Hormone