Premium
Effects of tamoxifen, an antiestrogen, on rat prostate carcinogenesis by 3,2′‐dimethyl‐4‐aminobiphenyl and testosterone do not support an estrogen role in testosterone promotion
Author(s) -
Miyata Emiko,
Kawabe Mayumi,
Sano Masashi,
Takesada Yasuko,
Takahashi Satoru,
Shirai Tomoyuki
Publication year - 1997
Publication title -
the prostate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.295
H-Index - 123
eISSN - 1097-0045
pISSN - 0270-4137
DOI - 10.1002/(sici)1097-0045(19970401)31:1<9::aid-pros2>3.0.co;2-k
Subject(s) - testosterone propionate , antiestrogen , prostate , estrogen , medicine , endocrinology , prostate cancer , tamoxifen , testosterone (patch) , carcinogenesis , toremifene , androgen , cancer , hormone , breast cancer
BACKGROUND Our previous data suggest that estrogen plays an important role in rat prostate carcinogenesis, particularly in promotion by testosterone. Therefore, in the present experiment, effects of an antiestrogen, tamoxifen (TAM), were investigated. METHODS Male F344 rats initially received 3,2′‐dimethyl‐4‐aminobiphenyl (DMAB) at 50 mg/kg bw every 2 weeks for 20 weeks and then TAM in Silastic tubes was subcutaneously given alone or together with testosterone propionate (TP) for 40 weeks. RESULTS TAM significantly suppressed prostate weights, suggesting an estrogenic action, but the development of preneoplastic and/or neoplastic lesions of the prostate or seminal vesicles in rats given DMAB alone or DMAB and TP was not altered. TAM reversed the suppression of development of ventral atypical hyperplasias by TP. CONCLUSIONS These findings suggest that estrogen, which is derived from testosterone by the action of aromatase, is not involved in the strong promotion by TP of DMAB prostate carcinogenesis. Prostate 31:9–13, 1997. © 1997 Wiley‐Liss, Inc.