Cancer preventive effect of Kumaizasa bamboo leaf extracts administered prior to carcinogenesis or cancer inoculation.
BACKGROUND
Kumaizasa bamboo found in Hokkaido is used for traditional medicine in Japan. The cancer preventive effect of vigorous (multistep) hot water extract of Kumaizasa was examined in relation to immunological conditioning and free radical scavenging activity.


METHODS
Cytokine induction in mice, free radical scavenging activity in vitro, and cancer preventive effect by oral administration of the vigorous extracts prior to tumor implantation or carcinogenesis by 7,12-dimethylbenz[a]anthracene (DMBA) were examined.


RESULTS
In tumor inoculated mouse models (S-180 sarcoma, Meth-A fibrosarcoma, B16-F10 melanoma), the vigorous extracts from Kumaizasa bamboo leaves suppressed tumor growth and prolonged survival significantly. In the chemical carcinogenesis model suppression of cancer incidence on day 100, tumor size and survival time were significantly improved with the vigorous extract, at/or above 0.03% in the diet, when given two weeks prior to the administration of the carcinogen.


CONCLUSIONS
The vigorous extracts of bamboo leaf show immunopotentiating and radical scavenging effects and administration prior to carcinogen exposure or tumor inoculation significantly suppresses tumor incidence and tumor growth and prolongs survival.
Laboratory of Microbiology and Oncology, Sojo University, 22-1, Ikeda 4-chome, Kumamoto 860-0082, Japan.
Takahiro
T
Seki
Hiroshi
H
Maeda
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005354:Fibrosarcoma / Q000378:metabolism / Q000517:prevention & control; D016166:Free Radical Scavengers / Q000494:pharmacology; D008297:Male; D008546:Melanoma, Experimental / Q000378:metabolism / Q000517:prevention & control; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000378:metabolism / Q000517:prevention & control*; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D012510:Sarcoma 180 / Q000378:metabolism / Q000517:prevention & control; D031787:Sasa / Q000737:chemistry*
D016588:Anticarcinogenic Agents; D016207:Cytokines; D016166:Free Radical Scavengers; D010936:Plant Extracts