PTTG expression in different experimental and human prolactinomas in relation to dopaminergic control of lactotropes

CRISTINA C; DIAZ-TORGA GS; GOYA RG,; KAKAR SS; PEREZ-MILLAN MI; PASSOS VQ; GIANNELLA-NETO D; BRONSTEIN MD; BECU-VILLALOBOS D

Mol Cancer

Año: 2007 vol. 6 p. 4 - 10

Pituitary tumor transforming gene (pttg) is a novel oncogene that is expressed at higher level in most of the tumors analyzed to date compared to normal tissues. Nevertheless, its expression in prolactinomas and its relation with the pituitary dopamine receptor 2 (D2R) are not well defined. We sought to determine the pituitary level of pttg in three different experimental models of prolactinomas with altered dopaminergic control of the pituitary: the dopaminergic D2R knockout female mouse, the estrogen-treated rat, and the senescent female rat. These three models shared the characteristics of increased pituitary weight, hyperprolactinemia, lactotrope hyperplasia and reduced or absent dopaminergic action at the pituitary level. We also studied samples from human macroprolactinomas, which were characterized as responsive or resistant to dopamine agonist therapy.