First Author | Katiyar SK | Year | 1993 |
Journal | Cancer Lett | Volume | 73 |
Issue | 2-3 | Pages | 167-72 |
PubMed ID | 8221629 | Mgi Jnum | J:280936 |
Mgi Id | MGI:6377195 | Doi | 10.1016/0304-3835(93)90260-g |
Citation | Katiyar SK, et al. (1993) Protective effects of green tea polyphenols administered by oral intubation against chemical carcinogen-induced forestomach and pulmonary neoplasia in A/J mice. Cancer Lett 73(2-3):167-72 |
abstractText | Our studies and others have shown the cancer chemopreventive effects of chronic administration of green tea in several animal tumor models. In this study, the administration of a polyphenolic fraction isolated from green tea (GTP) by oral intubation at a dose of 5 mg in 0.2 ml water 30 min prior to challenge with carcinogen, afforded significant protection against both diethylnitrosamine (DEN)- and benzo(a)pyrene (BP)-induced forestomach and lung tumorigenesis in A/J mice. The protective effects were evident by a decrease in numbers of tumors/mouse in GTP-fed groups compared to non GTP-fed controls. In the forestomach tumorigenesis protocol, GTP afforded 71 and 66% protection against, respectively DEN- and BP-induced tumor multiplicity. In the case of lung tumorigenesis protocol, however, the protective effects of GTP were 41 and 39%, respectively. Histological examination of forestomach tumors showed significantly lesser number of squamous cell carcinoma formation in GTP-fed groups of mice compared to carcinogen alone-treated controls. When pulmonary tumors were examined histologically, no adenocarcinomas were observed in GTP-fed groups compared to 15% mice with adenocarcinomas in DEN and BP alone-treated controls. The results of this study suggest that limited doses of GTP administration by gavage 30 min prior to carcinogen challenge may afford protection against carcinogen-induced tumorigenesis in internal body organs. |