Preventive effects of Juzen-taiho-to on N-methyl-N-nitrosourea and estradiol-17ß-induced endometrial carcinogenesis in mice
Kenji Niwa,2,
Midori Hashimoto,
Shigeo Morishita,
Zenglin Lian,
Keiko Tagami,
Hideki Mori,1 and
Teruhiko Tamaya
Department of Obstetrics and Gynecology and
1 Department of Pathology, Gifu University School of Medicine, 40 Tsukasa-machi, Gifu-city 500-8705, Japan
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Abstract
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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 transcriptionpolymerase 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.
Abbreviations: ADC, adenocarcinoma; AtH, atypical endometrial hyperplasia; EH, endometrial hyperplasia; E2, estradiol-17ß; RT-PCR, reverse transcription-polymerase chain reaction;; MNU, N-methyl-N-nitrosourea.
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Introduction
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Juzen-taiho-to, a Kampo (Japanese and Chinese traditional herbal) medicine, was first described during the Song dynasty (9601279 AD) in China, and was introduced to Japan during the Kamakura dynasty (11921333 AD)(1). Since then, it has been used as a nourishing agent, a so-called `Hozai' (in Japanese), for improving disturbances and imbalances in the homeostatic condition of the body. This drug is composed of 10 crude drugs and has been used effectively for plausible complaints of consumption of vital energy, lack of appetite, night sweats, circulatory problems and anemia (2,3). This agent is one of the mostly commonly used traditional herbal medicines in East Asia, i.e. Korea, China and Japan (2), and is administered to patients who are in various weakened conditions, including post-surgery patients and those with chronic illnesses, where it can alleviate general symptoms such as extreme fatigue, pale complexion, loss of appetite, dry or scaly skin, night sweating and dryness of the mouth (1). Currently, Juzen-taiho-to is often administered to cancer patients in Japan. To date, the biological effects of the Kampo formulas have been reported to include enhancement of phagocytosis (4), cytokine induction (5), antibody production (6) and spleen cell mitogenic activity (7). Additionally, there are some known clinical and experimental evidences indicating the augmentation of anti-tumor activity (810), prevention of cancer metastasis (1113) and protection from the deleterious effects of anti-cancer drugs (14) and irradiation (15,16).
It is generally accepted that gynecological cancers tend to be hormone (especially estrogen)-dependent. The transient expression of immediate early genes, c-fos/jun, is considered to relate cellular proliferation and differentiation (1719). c-Fos/jun mRNA in the uterine corpora of castrated mice is reported to be overexpressed by estrogens (2022). Previously, we have shown that Glycyrrhizae radix extract containing phytoestrogens, such as formononetin, has an inhibitory effect on endometrial carcinogenesis in mice, and the effect is consistent with suppression of c-fos/jun expression (23). Meanwhile, the ingredients of Juzen-taiho-to are known to contain several herbs, including Glycyrrhizae radix.
Therefore, the present study was conducted to assess whether Juzen-taiho-to exerts suppressive effects on the mouse uterine endometrial carcinogenesis by N-methyl-N-nitrosourea (MNU) and estradiol-17ß (E2), with the association of expression of c-fos/jun mRNA and their proteins, under the estrogenic effects. To avoid endogenous estrogenic effect, ovarectomized mice were used in the short-term experiment undertaken in this study.
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Materials and methods
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Animals and chemicals
Female ICR mice were purchased from Japan SLC Co. (Shizuoka, Japan). As a basal diet, Oriental MF (Oriental Yeast Co., Tokyo) was used. Diet and filtrated tap water were available ad libitum throughout the experiment. E2 and Juzen-taiho-to were purchased from Sigma Chemical Co. (St Louis, MO) and Tsumura Co. (Tokyo, Japan), respectively. The ingredients of Juzen-taiho-to are given in Table I
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Experimental protocol for short-term effects of Juzen-taiho-to
Female ICR mice, 12 weeks-of-age, were ovarectomized during a laparotomy under general anesthesia with diethylether. Two weeks later, the castrated mice were divided into three experimental groups (five mice in each). Group 1 was given a diet containing E2 (5 p.p.m.) and Juzen-taiho-to (0.2%). The dose of 0.2% Juzen-taiho-to in the diet was equivalent to the clinical dose (7.5 g/50 kg daily). Group 2 was fed with a diet containing E2 (5 p.p.m). Group 3 was given a diet containing Juzen-taiho-to (0.2%). Group 4 served as a control. Two weeks later, the uteri were resected and cut in half longitudinally. One half was quickly frozen in liquid nitrogen for the following experiments, and the other was submitted for pathological examination.
Reverse transcriptionpolymerase chain reaction (RTPCR)
Total RNA was isolated from frozen tissues by a guanidium thiocyanatephenolchloroform extraction method (24). Total RNA (3 µg) was reverse transcribed with Moloney murine leukemia virus reverse transcriptase (MMLV-RTase, 200 U, Gibco BRL, Gaithersburg, MD) in 20 µM TrisHCl (pH 8.4), 50 µM KCl, 2.5 µM MgCl2, 0.1 µg/ml bovine serum albumin, 10 µM dithiothreitol, and 0.5 µM deoxynucleotides to generate cDNAs, using random hexamers (50 ng, Gibco BRL) at 37°C for 60 min. RT reaction was heated at 94°C for 5 min to inactivate MMTLV-RTase. For c-fos or c-jun mRNA expression, 40 cycles of PCR, consisting of 1 min at 94°C for denaturation, 1 min at 55°C for annealing and 1 min at 72°C for extension, were carried out in reverse transcribed cDNAs and 0.1 mM specific primers described below, using IWAKI thermal sequencer TSR-300 (IWAKI Glass, Tokyo, Japan) with Vent DNA polymerase (New England Biolabs, Beverly, MA) in 10 µM KCl, 20 µM TrisHCl (pH 8.8), 10 µM (NH4)2SO4, 2 µM MgSO4, 0.1% Triton X-100 and 0.15 µM deoxynucleotide phosphates. Twenty cycles of PCR for glyceraldehyde-3-phosphate dehydrogenase (GAPDH, a house-keeping gene) mRNA as an internal strandard were performed similarly.
The following oligodeoxynucleotides were synthesized as specific primers in PCR according to published information [cDNAs for c-fos (25), c-jun (26), and GAPDH (27)]: sense for c-fos, 5'-CTTACGCCAGAGCGGGAATG-3'; anti-sense for c-fos, 5'-AAGCCTCAGGCAGACCTCCA-3'; sense for c-jun, 5'-AGAGCATGACCTTGAAC-3'; anti-sense for c-jun, 5'-CTGGGA- AGCGTGTTCTGGCT-3'; sense for GAPDH, 5'-TGAAGGTCGGTGTG- AACGGATTTGG-3'; antisense for GAPDH, 5'-CTCCTTGGAGGCCA- TGTAGGCCAT-3'.
Semi-quantitative analysis of c-fos/jun mRNA expressions by Southern blot of PCR products
PCR products were applied to 1.2% agarose gel for electrophoresis performed at 50100V. PCR products were capillary-transferred to Immobilon transfer membrane (Millipore, Bedford, MA) for 16 h. The membrane was dried at 80°C for 30 min and UV-irradiated to tightly fix PCR products. PCR products on the membrane were prehybridized in 1 M NaCl, 50 mM TrisHCl (pH 7.6) and 1% sodium dodecyl sulfate at 42°C for 1 h, and hybridized in the same solution with biotinylated oligodeoxynucleotide probes synthesized from the sequences between the specific individual primers of c-fos or c-jun at 65°C overnight. Specific bands hybridized with biotinylated probes were detected with Plex Luminescent Kits (Millipore) on the membranes after exposure to X-ray film at room temperature for 10 min. The quantification of Southern blot was carried out with Bio image (Millipore). The intensity of specific bands was standardized with that of GAPDH mRNA.
Immunohistochemical expressions of c-fos and c-jun protein
After fixing in 10% formalin, half of the uterine corpus was processed for conventional staining methods. Briefly, the avidinbiotinperoxidase complex was applied on the sections using a Vestain kit (Vector Laboratories, Burlingame, CA). The primary antibodies against the proteins of c-fos and c-jun (anti-rabbit polyclonal, Oncogene Science, NY) were used at 1:100 dilution. Staining intensity was assigned as follows (23): (+), positive; (+/), minimally or randomly positive; (), negative.
Experimental protocol for long-term effects of Juzen-taiho-to
Experimental protocol is shown in Figure 1
. A total number of 93 female ICR mice, 10 weeks-of-age, underwent a laparotomy under general anesthesia with diethylether. MNU solution (total volume 0.1 ml) at a dose of 1 mg/100 g body weight was injected into the left uterine tube and normal saline into the right. One week after MNU exposure, the animals were divided into the following four experimental groups. Group 1 (18 mice) was given a diet of 0.2% Juzen-taiho-to and 5 p.p.m. E2. Group 2 (30 mice) received a diet of 5 p.p.m. E2 alone. Group 3 (15 mice) was given a diet mixed with 0.2% Juzen-taiho-to. Group 4 (30 mice) was kept on the basal diet alone and treated as a control. Thirty weeks after exposure to MNU, all animals were killed and autopsied. All major organs, especially reproductive organs, were grossly inspected. The uterus, ovaries, vagina and other lesions suspected of being neoplastic and hyperplastic were cut in half. The tissues were submitted for histopathological examination. Tissues were sectioned at a thickness of 3 µm and stained with hematoxylin and eosin.

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Fig. 1. Experimental design. Arrows: MNU solution at a dose of 1 mg/100 g body weight was injected into the left uterine tube, and normal saline into the right.
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Histology of the uterine lesions
According to the WHO criteria (28), uterine endometrial lesions were divided into four lesions: (i) endometrial hyperplasia (EH), simple; (ii) EH, complex; (iii) atypical endometrial hyperplasia (AtH); (iv) adenocarcinoma (ADC).
Statistical analysis
Statistical analysis was done according to the
2 test or Student's t-test.
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Results
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Short-term experiment
The mean wet weights of the left uterine corpora were as follows: group 1 [E2 plus Juzen-taiho-to (n = 5)], 0.13 ± 0.04 g; group 2 [E2 alone (n = 5)], 0.14 ± 0.03 g; group 3 [Juzen-taiho-to (n = 5)], 0.10 ± 0.05 g; group 4 [no treatment (n = 5)], 0.06 ± 0.03 g. No significant differences were found between groups 1 and 2, and 3 and 4. The levels of c-fos and c-jun mRNA expressions are shown in Figure 2
. Juzen-taiho-to significantly decreased the E2-induced expression of c-fos (P < 0.05). The agent also tended to decrease the expression of c-jun mRNA levels.

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Fig. 2. Expression of c-fos and c-jun mRNA in the uterus of ovarectomized mice treated continuously for 12 weeks with E2 plus Juzen-taiho-to, E2 alone or juzen-taiho-to alone in the diet. *P < 0.05, **P < 0.01.
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Immunohistochemical expression of c-fos and c-jun oncoproteins is summarized in Table II
. The expression of c-fos and c-jun oncoproteins was prominently seen in glandular cells treated with E2, and was decreased by Juzen-taiho-to.
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Table II. Immuohistochemical expression of c-fos and c-jun of castrated mouse uterus after 2 weeks feeding with E2 plus Juzen-taiho-to, E2 alone orJuzen-taiho-to alone
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Long-term experiment
Four mice in group 1, six in group 2, three in group 3 and four in group 4 died within 15 weeks, yet no pathological abnormalities other than pneumonia were found. The remaining animals survived until the termination of the experiment and were enrolled as the effective animals (Table III
). No significant difference in mean body weights was found between the groups 1 and 2, and 3 and 4. Under E2-treatment, the mean wet weight of left or right uterine corpora of group 1 was smaller than that of group 2 (P < 0.05). The mean wet weight of the right uterine corpora of group 3 was also significantly smaller than that of the control group 4 (P < 0.05).
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Table III. Mean body weight, and mean weight of left (treated) and right (control) uterine corpora of mice in each group
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Histological properties of EH and ADC in this study were the same as in our previous report (20). All ADCs seen in the endometria were well- or moderately-differentiated (Figure 3
). The incidence of the preneoplastic and neoplastic lesions of the endometria is summarized in Table IV
. The incidence of ADC and the other three hyperplastic lesions of the treated side of the uterine corpus of group 1 (treated with E2 plus Juzen-taiho-to) was significantly smaller than that of group 2 (treated with E2 alone). In the right (control) uterine corpus, the incidence of simple EH in group 1 was significantly smaller than in group 2 (P < 0.01).

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Fig. 3. Moderately differentiated ADC of the endometrium in a mouse treated with MNU and E2 (HE x180).
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Pathological evidence of ovary, oviduct and vagina was as follows. Cystic ovaries were commonly seen in mice treated with E2 (groups 14: 50, 55, 40 and 38%, respectively, in the left ovary). Corpora lutea were frequently recognized (groups 14: 93, 95, 92 and 93%, respectively, in the left ovary). Marked epithelial hyperplasia in the oviduct, diagnosed as `progressive proliferative lesion' (29), was commonly observed in mice of groups 1 (86%), 2 (100%), 3 (83%) and 4 (12%, P < 0.001). Papillary lesions (21) in the vagina were infrequently present in groups 1 (14%), 2 (13%), 3 (17%) and 4 (8%).
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Discussion
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Kampo medicine, a form of complementary or alternative medicine, is considered to be potentially effective in clinical as well as scientific medical usage. In general, formulas in Kampo medicine consist of a variety of herbal ingredients, possessing combined, additive or adjunctive biological functions. The use of Kampo medicine has been increasing, since the medicine tends to extend to the adjunctive for cancer therapy (30).
In this study, Juzen-taiho-to suppressed estrogen-induced expression of c-fos/jun mRNA and their oncoproteins in the uterine corpora of castrated mice. c-Fos and c-jun are reported to fluctuate with the estrous cycle in response to estrogens (31). This, however, is considered to have been avoided in the ovarectomized mice used in the present study. As a result of the long-term experiment, Juzen-taiho-to also decreased the uterine weight overgrowth induced by estrogen, yet the inhibition was not recognized in the short-term experiment. Inhibitory effects of Juzen-taiho-to in endometrial carcinogenesis were prominent in the groups treated with E2. These results suggest that Juzen-taiho-to has an anti-carcinogenic effect, possibly via suppression of estrogen-related events.
In the present study, the effects of Juzen-taiho-to on other tissues of the reproductive tract were examined. In all groups of the long-term experiment, corpora lutea were frequently recognized in the ovaries, in contrast to the lack of corpora lutea found after treatment with tamoxifen in our previous report (22). Thus, an estrogenic effect of Juzen-taiho-to could not be seen at the dose used in this study.
Juzen-taiho-to is known to possess anti-metastatic effects in some animal models (1113). The mechanism for the effects may be through activation of macrophage and/or T cells in the host immune system (13). Juzen-taiho-to is reported to exert an anti-metastatic effect (13) and an inhibitory effect for the growth of transfected cells (32). This study first demonstrates the inhibitory effects of Juzen-taiho-to on endometrial carcinogenesis stimulated by E2. The present data also imply that the inhibitory effects are related to the suppression of c-fos and c-jun expression. As shown in Table I
, some ingredients of Juzen-taiho-to have phytoestrogens like formonenetin. Glycyrrhizin is reported to exhibit anti-estrogenic actions (33). Accordingly, it is suggested that Juzen-taiho-to exerts anti-carcinogenic effects via mechanisms relating to modifying the action of estrogen. Results of this present study suggest that Juzen-taiho-to is a promising agent for the prevention of human endometrial cancer as well as a complementary or alternative medicine.
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Notes
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2 To whom correspondence should be addressed E-mail: kniwa{at}cc.gifu-u.ac.jp 
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References
|
---|
-
Saiki,I. (2000) A kampo medicine `Juzen-taiho-to'. Prevention of malignant progression and metastasis of the tumor cells and the mechanism of action. Biol. Pharm. Bull., 23, 677688.[ISI][Medline]
-
Tei,S. (1996) Juzen-taiho-to. Kampo Igaku., 20, 2429 (in Japanese).
-
Greene,R.F., Chatterji,D.C., Hiranaka,P.K. and Gallelli,J.F. (1979) Stability of cisplatin in aqueous solution. Am. J. Hosp. Pharm., 36, 3843.[ISI][Medline]
-
Maruyama,H., Kawamura,H., Takemoto,N., Komatsu,Y., Aburada,M. and Hosoya,E. (1998) Effect of Juzentaihoto on phagocytosis. Jpn. J. Inflamm., 8, 461465 (in Japanese).
-
Kubota,A., Okamura,S., Shimoda,K., Harada,N., Omori,F. and Niho,Y. (1992) A traditional herbal medkicine, Juzen-taiho-to, augments the production of granulocyte/macropharge colony-stimulating factor from human peripheral blood mononuclear cells in vitro. Int. J. Immunother., 8, 191195.[ISI]
-
Hamada,M., Fujii,Y., Yamamoto,H., Miyazawa,Y., Shui,S.M., Tung,Y.C. and Yamaguchi,N. (1988) Effect of a Kampo medicine, zyuzentaihoto, on the immunoreactivity of tumor bearing mice. J. Ethnopharma., 24, 311320.
-
Kiyohara,H., Takemoto,N., Komatsu,Y., Kawamuraz,H., Hosoya,E. and Yamada,H. (1991) Characterization of mitogenic optic polysacccharides from Kampo (Japanese herbal) medicine `Juzen-Taiho-To'. Plant Med., 57, 254259.[ISI]
-
Maruyama,H., Takemoto,N., Maruyama,N., Komatsu,Y. and Kawamura,H. (1993) Antitumor effect of Juzentaiho-to, a Kampo medicine, combined with surgical excision of transplanted Meth-A-fibrosarcoma. Int. J. Immunother., 9, 117125.[ISI]
-
Haranaka,R., Hasegawa,R., Nakagawa,S., Sakurai,A., Satomi,N. and Haranaka,K. (1988) Antitumor activity of combination therapy with traditional Chinese medicine and OK432 or MMC. J. Biol. Response Mod., 7, 7790.[ISI][Medline]
-
Sugiyama,K., Ueda,H., Ichiko,Y. and Yokota,M. (1995) Improvement of cisplatin toxicity and lethality by Juzen-taiho-to in mice. Biol. Pharm. Bull., 18, 5358.[ISI][Medline]
-
Ohnishi,Y., Fujii,H., Kimura,F., Mishima,T., Murata,J., Tazawa,K., Fujimaki,M., Okada,F., Hosokawa,M. and Saiki,I. (1996) Inhibitory effect of a traditional Chinese Medicine, Juzen-taiho-to, on progressive growth of weakly malignant clone cells derived from murine fibrosarcoma. Jpn J. Cancer Res., 87, 10391044.[ISI][Medline]
-
Ohnishi,Y., Fujii,H., Hayakawa,Y. et al., (1998) Oral administration of a Kampo (Japanese herbal) medicine Juzen-taiho-to inhibits liver metastasis of colon 26-L5 carinoma cells. Jpn J. Cancer Res., 89, 206213.[ISI][Medline]
-
Ohnishi,Y., Yamamura,T., Tauchi,K., Sakamoto,T., Tsukada, K., Nomura, S., Komatsu,Y. and Saiki,I. (1988) Expression of the anti-metastatic effect induced by Juzen-taiho-to is based on the content of Shimotsu-to constituents. Biol. Pharm. Bull., 21, 761765.
-
Sugiyama,K., Ueda,H. and Ichiko,Y. (1995) Protective effect of Juzen-taiho-to against carboplatin-induced toxic side effects in mice. Biol. Pharm. Bull., 18, 544548.[ISI][Medline]
-
Kawamura,H., Maruyama,H., Takemoto,N., Maruyama,N., Komatsu,Y., Aburada,M., Ikehara,S. and Hosoya,Y. (1989) Accelerating effect of Japanese Kampo medicine on recovery of murine haematopoietic stem cells after administration of mitomycin C. Int. J. Immunother., 5, 3542.[ISI]
-
Ohnishi,Y., Yasuzumi,R., Fan,H., Liu,L., Takao-Liu,F., Komatsu,Y., Hosoya,E. Good,R.A. and Ikehara,S. (1990) Effect of Juzen-taiho-toh (TJ-48), a traditional oriental medicine, on haematopoietic recovery from radiation injury in mice. Exp. Hematol., 18, 1822.[ISI][Medline]
-
Adamson,E.D. (1987) Oncogenes in development. Development, 99, 449471.[ISI][Medline]
-
Weitz,A. and Bresciania,F. (1988) Estrogen induces expression of c-fos and c-myc protooncogenes in the rat uterus. Mol. Endocrionol 2, 816824.[Abstract]
-
Weitz,A., Cicatiello,L., Persiot,E., Scalona,M. and Bresciani,F. (1990) Estrogen stimulation of transcription of c-jun protooncogene. Mol. Endocrinol., 4, 10311050.
-
Niwa,K., Murase,T., Furui,T., Morishita,S., Mori,H., Tanaka,T., Mori,H. and Tamaya,T. (1993) Enhancing effects of estrogens on endometrial carcinogenesis initiated by N-methyl-N-nitrosourea in ICR mice. Jpn J. Cancer Res., 84, 951955.[ISI][Medline]
-
Morishita,S., Niwa,K., Ichigo,S., Hori,M., Murase,T., Fujimoto,J. and Tamaya,T. (1995) Overexpression of c-fos/jun mRNA and their oncoproteins (Fos/Jun) in the mouse uterus treated with three natural estrogens. Cancer Lett., 97, 225231.[ISI][Medline]
-
Niwa,K., Morishita,S., Hashimoto,M., Itoh,T., Fujimoto,J., Mori,H. and Tamaya,T. (1998) Effects of tamoxifen on endometrial carcinogenesis in mice. Jpn J. Cancer Res., 89, 502509.[ISI][Medline]
-
Niwa,K., Hashimoto,M., Morishita,S., Yokoyama,Y., Mori,H. and Tamaya,T. (1999) Preventive effects of Glycyrrhzae radix extract on estrogen-related endometrial carcinogenesis in mice. Jpn J. Cancer Res., 90, 726732.[ISI][Medline]
-
Chomczynski,P. and Sacchi,N. (1987) Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal. Biochem., 162, 156159.[ISI][Medline]
-
van Beveren,C., van Straaten,F., Curran,T., Müller,R. and Verma,I.M. (1983) Analysis of FBJ-MuSV provirus and c-fos (mouse) gene reveals that viral and cellular fos gene products have different carboxy termini. Cell, 32, 12411255.[ISI][Medline]
-
Lamph,W.W., Wamsley,P., Sassone,Corsi,P. and Verma,I.M. (1988) Induction of protooncogene jun/AP-1 by serum and TPA. Nature, 334, 629631.[ISI][Medline]
-
Sabath,D., Broome,H.E. and Prystowsky,M.B. (1990) mRNA is a major interleukin 2-induced transcript in a cloned T-helper lymphocyte. Gene, 91, 185191.[ISI][Medline]
-
Silverberg,S.G. (1994) Uterine corpus. Epithelial tumours and related lesions. In Scully,R.E., Bonfiglio,T.A., Kurman,R.J., Silverburg,S.G. and Wilkinson,E.L. (eds) Histological Typing of Female Genital Tract Tumours, 2nd Edn WHO, Geneva, pp. 1318.
-
Newbold,R.R., Jefferson,W.N., Padilla-Burgos,E. and Bullock,B.C. (1997) Uterine carcinomas in mice treated neonatally with Tamomifen. Carcinogenesis, 18, 22932298.[Abstract]
-
Wenner,C.A., Parker,K., Simon,M.A., Adams,L., Greene,K. and Standish,L.J. (1999) Botanical medicines with gynecologic anticancer activity. A literature review. J. Am. Med. Wom. Assoc., 54, 184190.[Medline]
-
Padmannabhan,V., Dalkin,A., Yasin,M., Haisenleder,D.J., Marshall,J.C. and Landefeld,T.D. (1995) Are immediate early genes involved in gonadotropin-releasing hormone receptor regulation? Characterization of changes in GnRH receptor (GnRH-R), c-fos, and c-jun messenger ribonucleic acids during the ovine estrous cycle. Biol. Reprod., 53, 263269.[Abstract]
-
Tsai,W., Nagasawa,H., Tsuno,N., Tominaga,O. and Muto,T. (1995) Anti-tumoral effects of herbal medicines. Prog. Med., 15, 19771981 (in Japanese).
-
Kumagai,A., Nishino,K., Shimoyama,A., Kin,T. and Yamamura,Y. (1967). Effect of glycyrrhizin on estrogen action. Endorinol. Jpn, 14, 3438.
Received April 18, 2000;
revised November 22, 2000;
accepted November 22, 2000.