Effects of the aromatase inhibitor 4-hydroxyandrostenedione and the antiandrogen flutamide on growth and steroid levels in DMBA-induced rat mammary tumors

Using dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in the rat as model, comparison was made of the effect of treatment for 20 days with the aromatase inhibitor 4-hydroxyandrostenedione (4-OH-A) (7.5 mg, twice daily) or the antiandrogen flutamide (5 mg, twice daily) on tumor growth as well as on plasma and tumor content of estrogens, androgens, and their precursors and metabolites. Tumor number and size were markedly decreased following treatment with either drug, the effect of treatment being more important on size than number, and on new tumors which developed during treatment than on tumors already present at start of treatment. Treatment with the aromatase inhibitor 4-OH-A caused a parallel decrease in plasma and tumor levels of pregnenolone (Preg), progesterone (P), and 17-OH P, while there was a marked increase in dehydroepiandrosterone (DHEA), androst-5-ene-3 beta,17 beta-diol (delta 5-diol), androstenedione (delta 4-dione), testosterone (T), androstane-3 alpha, 17 beta-diol (3 alpha-diol), and androstane-3 beta,17 beta-diol (3 beta-diol), with no significant change in dihydrotestosterone (DHT) and 17 beta-estradiol levels. The marked increase in tissue T content coupled to a decrease in P levels could well contribute to the inhibition of tumor growth induced by 4-OH-A. Flutamide, on the other hand, caused a marked fall in plasma and tissue levels of Preg, 17-OH Preg, P, and 17-OH P, with no significant change in the concentration of the other steroids, thus suggesting a possible role of the fall in tissue P levels in the inhibition of tumor growth. Since both drugs are potent inhibitors of DMBA-induced tumor growth in intact animals, better knowledge of their mechanism of action should add to our understanding of the multiple endocrine factors controlling the growth of these tumors.

Medienart:

Artikel

Erscheinungsjahr:

1988

Erschienen:

1988

Enthalten in:

Zur Gesamtaufnahme - volume:12

Enthalten in:

Breast cancer research and treatment - 12(1988), 3 vom: 01. Dez., Seite 287-96

Sprache:

Englisch

Beteiligte Personen:

Spinola, P G [VerfasserIn]
Marchetti, B [VerfasserIn]
Mérand, Y [VerfasserIn]
Bélanger, A [VerfasserIn]
Labrie, F [VerfasserIn]

Themen:

409J2J96VR
57-97-6
76W6J0943E
9,10-Dimethyl-1,2-benzanthracene
Androstenedione
Anilides
Flutamide
Formestane
Journal Article
PUB9T8T355
Research Support, Non-U.S. Gov't
Steroids

Anmerkungen:

Date Completed 19.04.1989

Date Revised 03.09.2019

published: Print

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM031290469