Duration dependent induction of invasive prostatic carcinomas with pharmacological dose of testosterone propionate in rats pretreated with 3,2'-dimethyl-4-aminobiphenyl and development of androgen-independent carcinomas after castration.
Male F344 rats were first treated with 3,2'-dimethyl-4-aminobiphenyl for 20 weeks in the presence of testicular androgens and then administered of a pharmacological dose of testosterone propionate (TP) for various periods (maximum 40 weeks). This resulted in development of invasive carcinomas in the dorso-lateral prostate as well as the seminal vesicles whose incidences were TP duration-dependent. However, in situ carcinomas of the ventral prostate were not affected by the TP treatment and atypical hyperplasias were clearly decreased. When animals were subjected to orchiectomy after 20-weeks-treatment with the TP, invasive adenocarcinomas were still subsequently noted in the dorso-lateral prostate and seminal vesicles, demonstrating a certain androgen-independence. The data indicate that, in spite of the necessity of high dose of TP for induction of invasive prostate carcinomas in the present experimental model, a proportion of the resulting tumors are hormone-independent.
Shirai
T
T
First Department of Pathology, Nagoya City University Medical School, Japan.
Sano
M
M
Imaida
K
K
Takahashi
S
S
Mori
T
T
Ito
N
N
D000611:Aminobiphenyl Compounds / Q000008:administration & dosage*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002273:Carcinogens; D002277:Carcinoma / Q000139:chemically induced*; D008297:Male; D009362:Neoplasm Metastasis; D009919:Orchiectomy; D009929:Organ Size / Q000187:drug effects; D011471:Prostatic Neoplasms / Q000139:chemically induced*; D051381:Rats; D011916:Rats, Inbred F344; D013739:Testosterone / Q000008:administration & dosage*
D000611:Aminobiphenyl Compounds; D002273:Carcinogens; C001042:2',3-dimethyl-4-aminobiphenyl; D013739:Testosterone