Suppressive effects of dietary genistin and daidzin on rat prostate carcinogenesis.
High intake of phytoestrogens through soybeans and their products is thought to be associated with low incidences of prostate and / or breast cancer in Asian countries. Possible chemopreventive effects of genistin or daidzin on rat prostate carcinogenesis were therefore investigated. Male F344 rats were given 10 biweekly subcutaneous injections of 3,2'-dimethyl-4-aminobiphenyl (DMAB) and then either genistin or daidzin in the diet at a concentration of 0.1% for 40 weeks. Other groups of rats given DMAB were treated with genistin or daidzin together with a high dose of testosterone propionate (TP). Both genistin and daidzin reduced the numbers of ventral prostate carcinomas (P < 0.05), with a tendency for decrease in incidence. Invasive carcinomas which developed in the anterior prostate and seminal vesicles with TP were, however, not influenced by the two isoflavones. Thus, the present data suggest that genistin and daidzin possess anti-cancer effects at relatively early stages of prostate cancer development, providing experimental support for epidemiological findings.
Kato
K
K
First Department of Pathology, Nagoya City University Medical School, Mizuho-ku, Nagoya 467-8601, Japan. kojikato@med.nagoya-cu.ac.jp
Takahashi
S
S
Cui
L
L
Toda
T
T
Suzuki
S
S
Futakuchi
M
M
Sugiura
S
S
Shirai
T
T
D000611:Aminobiphenyl Compounds; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D004968:Estrogens, Non-Steroidal / Q000627:therapeutic use; D007529:Isoflavones / Q000627:therapeutic use*; D008297:Male; D009361:Neoplasm Invasiveness; D009929:Organ Size / Q000187:drug effects; D011471:Prostatic Neoplasms / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D051381:Rats; D011916:Rats, Inbred F344; D013739:Testosterone; D014407:Tumor Cells, Cultured
D000611:Aminobiphenyl Compounds; D004791:Enzyme Inhibitors; D004968:Estrogens, Non-Steroidal; D007529:Isoflavones; C001042:2',3-dimethyl-4-aminobiphenyl; C040641:genistin; D013739:Testosterone; C013908:daidzin