Carcinogenesis, Vol. 22, No. 4, 587-591,
April 2001
© 2001 Oxford University Press
MOLECULAR EPIDEMIOLOGY AND CANCER PREVENTION |
Preventive effects of Juzen-taiho-to on N-methyl-N-nitrosourea and estradiol-17ß-induced endometrial carcinogenesis in mice
Department of Obstetrics and Gynecology and
1 Department of Pathology, Gifu University School of Medicine, 40 Tsukasa-machi, Gifu-city 500-8705, Japan
Two experiments were conducted to determine effects of Juzen-taiho-to on endometrial carcinogenesis in mice. In the first experiment, Juzen-taiho-to treatment (2 weeks) decreased the levels of estradiol-17ß (E2)-stimulated expression of c-fos/jun mRNA and their oncoproteins, determined by reverse transcription–polymerase chain reaction and Southern blot analysis, and the immunohistochemical method, in the uteri of ovarectomized mice. For the second experiment, 93 female ICR mice were given N-methyl-N-nitrosourea (MNU) solution (1 mg/100 g body weight) and normal saline (as controls) into their left and right uterine corpora, respectively, and were divided into four groups. Group 1 was given a diet containing 0.2% Juzen-taiho-to and 5 p.p.m. E2. Group 2 was given a diet containing 5 p.p.m. E2 alone. Group 3 was given a diet containing 0.2% Juzen-taiho-to alone. Group 4 was kept on the basal diet alone and treated as a control. Juzen-taiho-to treatment significantly decreased incidences of the uterine endometrial atypical (P < 0.01), complex (P < 0.05) and simple hyperplasias (P < 0.01), under estrogenic stimulation. It is suggested that Juzen-taiho-to has an inhibitory effect on E2-related endometrial carcinogenesis in mice, relevantly through suppression of estrogen-induced c-fos/jun-expression.