TY - JOUR
T1 - Wakame seaweed suppresses the proliferation of 7,12-dimethylbenz(a)-anthracene-induced mammary tumors in rats
AU - Funahashi, Hiroomi
AU - Imai, Tsuneo
AU - Tanaka, Yuji
AU - Tsukamura, Kyousuke
AU - Hayakawa, Yasusyuki
AU - Kikumori, Toyone
AU - Mase, Takahiro
AU - Itoh, Takahiro
AU - Nishikawa, Mikiko
AU - Hayashi, Hiromiti
AU - Shibata, Arihiro
AU - Hibi, Yatsuka
AU - Takahashi, Masahide
AU - Narita, Tatsuhiko
PY - 1999/9
Y1 - 1999/9
N2 - We examined the anti-tumor proliferation effects of wakame seaweed on 7,12-dimethylbenz(a)-anthracene (DMBA)-induced rat mammary tumor. DMBA was administered to 8-week-old female Sprague-Dawley rats, and rats which developed mammary tumors were assigned randomly to three groups. Commercial rat feed was used in a control group (group I-A), and two feed mixtures were prepared, which contained commercial rat feed blended with wakame at 1.0% (group I-B) and 5.0% (group I-C) by weight. The respective feeds were given to each group for 8 weeks, and changes in mammary tumor size were compared. At the end of the experiment, mammary tumors and thyroid glands were resected to compare their weights. Serum total iodine and thyroxin (T4) levels were measured. Immunohistochemical studies for bromodeoxyuridine (BrdU) labeling, transforming growth factor (TGF)-β, and apoptosis were carried out in the resected tumor. Significant suppression of tumor growth was observed in groups I-B and I-C compared with I-A. In groups I-B and I-C, the weights of resected mammary tumors were significantly lower and serum total iodine concentration was significantly higher than in I-A. BrdU indices were significantly lower in groups I-B and I-C, compared with I-A. TGF-β and apoptotic index were inversely related to BrdU. These results suggest that iodine is transported from the serum into mammary tissues and induces apoptosis through the expression of TGF-β. In conclusion, wakame suppressed the proliferation of DMBA-induced mammary tumors.
AB - We examined the anti-tumor proliferation effects of wakame seaweed on 7,12-dimethylbenz(a)-anthracene (DMBA)-induced rat mammary tumor. DMBA was administered to 8-week-old female Sprague-Dawley rats, and rats which developed mammary tumors were assigned randomly to three groups. Commercial rat feed was used in a control group (group I-A), and two feed mixtures were prepared, which contained commercial rat feed blended with wakame at 1.0% (group I-B) and 5.0% (group I-C) by weight. The respective feeds were given to each group for 8 weeks, and changes in mammary tumor size were compared. At the end of the experiment, mammary tumors and thyroid glands were resected to compare their weights. Serum total iodine and thyroxin (T4) levels were measured. Immunohistochemical studies for bromodeoxyuridine (BrdU) labeling, transforming growth factor (TGF)-β, and apoptosis were carried out in the resected tumor. Significant suppression of tumor growth was observed in groups I-B and I-C compared with I-A. In groups I-B and I-C, the weights of resected mammary tumors were significantly lower and serum total iodine concentration was significantly higher than in I-A. BrdU indices were significantly lower in groups I-B and I-C, compared with I-A. TGF-β and apoptotic index were inversely related to BrdU. These results suggest that iodine is transported from the serum into mammary tissues and induces apoptosis through the expression of TGF-β. In conclusion, wakame suppressed the proliferation of DMBA-induced mammary tumors.
KW - Apoptosis
KW - DMBA-induced rat mammary tumor
KW - Immunohistochemistry
KW - TGF-β
KW - Wakame
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U2 - 10.1111/j.1349-7006.1999.tb00836.x
DO - 10.1111/j.1349-7006.1999.tb00836.x
M3 - Article
C2 - 10551319
AN - SCOPUS:0032725508
SN - 0910-5050
VL - 90
SP - 922
EP - 927
JO - Japanese Journal of Cancer Research
JF - Japanese Journal of Cancer Research
IS - 9
ER -
