Proopiomelanocortin heterozygous and homozygous null mutant mice develop pituitary adenomas.


Journal Article

Mice lacking all pro-opiomelanocortin (POMC)-derived peptides have been created by gene targeting of the POMC locus in embryonic stem cells. Phenotypes of the POMC null homozygous mutants include obesity, pigmentation defects, and adrenal insufficiency. Here, we report that both POMC null homozygous and heterozygous mutants also develop pituitary gland tumors, which result in their premature death. The tumors occur with 100% penetrance in both POMC heterozygous and homozygous genotypes. Histological examinations reveal that tumors start from hyperplastic focal points of melanotrophic cells within the intermediate lobe. Based on the morphological and immunohistological features, we have classified the tumors as non-invasive, non-secreting, intermediate lobe adenomas. These findings uncover potential novel roles of melanocortins in the regulation of cell proliferation.

Full Text

Cited Authors

  • Karpac, J; Ostwald, D; Li, GY; Bui, S; Hunnewell, P; Brennan, MB; Hochgeschwender, U

Published Date

  • January 2006

Published In

Volume / Issue

  • 52 / 2

Start / End Page

  • 47 - 52

PubMed ID

  • 16914086

Pubmed Central ID

  • 16914086

Electronic International Standard Serial Number (EISSN)

  • 1165-158X

International Standard Serial Number (ISSN)

  • 0145-5680


  • eng