RESUMO
The effects of testosterone (T), dihydrotestosterone (DHT) and methyltrienolone (R 1881) on cell proliferation of eight human pituitary tumors in culture wre assessed by [3H]thymidine incorporation and compared to those of progesterone (Pg) and 17 beta-estradiol. Receptors for androgens (AR), estrogens (ER) and progesterone (PgR) were characterized. AR had a significant inhibitory effect on all AR-positive tumors, whatever their hormonal content. Inhibitory effects of either T and DHT < R1881 < Pg were observed in tumors co-expressing AR and PgR. The inhibitory effect of R 1881 on a PgR-positive/AR-negative tumor suggested that R 1881 action was partially PgR-mediated. The effects of either T or the nonaromatizable DHT and R 1881 were unrelated to ER expression. We conclude that AR can modulate the growth of human pituitary tumors through direct receptor-mediated intracellular pathways which may be common to various pituitary cell types.
Assuntos
Adenoma/patologia , Androgênios/farmacologia , Estradiol/farmacologia , Neoplasias Hipofisárias/patologia , Progesterona/farmacologia , Adenoma/sangue , Adenoma/tratamento farmacológico , Adenoma/cirurgia , Adulto , Bromocriptina/uso terapêutico , Divisão Celular/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio do Crescimento/sangue , Antagonistas de Hormônios/farmacologia , Humanos , Lisurida/uso terapêutico , Masculino , Metribolona/farmacologia , Pessoa de Meia-Idade , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/cirurgia , Prolactina/sangue , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Testosterona/farmacologia , Timidina/metabolismo , Trítio , Células Tumorais CultivadasRESUMO
Six human pituitary adenoma cultures, characterized for estrogen and progesterone (Pg) receptors, were treated with 17 beta-estradiol (17 beta-E2), Pg and tamoxifen (TAM) at different concentrations, alone and in combination, for 2, 4 and 8 days. Cell proliferation data showed in most cases a stimulating effect of 17 beta-E2 and an inhibitory effect of Pg on cell growth, which appeared to be correlated with specific receptor expression, but independent of pituitary cell hormone content. A marked inhibitory effect of TAM on cell proliferation was present in all cases, but, on the contrary, was independent of estrogen receptor expression.
