| In the present dissertation, 197 species of Chinese herbal medicines (a total of 247 samples), collected from the area of Yunnan, Sichuan, Xinjiang and Liaoning, were examined for their cell cycle inhibitory and apoptosis inducing activities using tsFT210 cells, a mouse temperature sensitive cdc2 mutant cell line. The result suggest that 27 species are effective and the positive efficiency is 14%.In the course of screening, we found that the ethanol extract of fruit of Vitex trifolia L., collected from Sichuan province, possesed strong anticancer activity. The extract showed obvious cell cycle inhibitory and apoptosis inducing activities on tsFT210 cells. Vitex trifolia L. is attributed to the genus Vitex (Verbenaceae) and the dried fruit has been used as a traditional Chinese medicine, Fructus Vitics (Manjingzi in Chinese name), for the treatment of colds, headache, migraine, eye-pain, etc, which was recorded in Pharmacopoeis of P.R.C, 2000. Also it is used as a folk medicine to cure certain cancers in partail area of China. Although some components, mainly essential oil, diterpenes, flavonoids, have been reported for the title plant, no research report had been seen on its anticancer components.In order to clarify the anticancer components and the principles for anticancer usage, we carried out the chemical and biological investigation of anticancer components of the Vitex trifolia L.. In process of isolation, guided by bioassay of cell cycle inhibitory and apoptosis inducing activities using tsFT210 cells, we determined the active parts and fractions then confirmed the isolating scheme for active components by micro-quantity test. Eighteen compounds were isolated and their chemical structures were identified on the basis of the physico-chemical properties and spectra data. Among them, compounds 1-6 belong to labdane-type diterpenes, 7-13 are flavonoids, 14-18 are iridoid, lignan, steroid, phenolic and fatty acids respectively. Compounds 8,15 and 16 were isolated from the genus Vitex for the first time.On the basis of previous chemical study, inhibitory effects of compounds on the proliferation of mammalian cancer cells were evaluated by MTT method and their effectson cell cycle and apoptosis were investigated by flow cytometry, accompanied with morphological observation under light microscope. The anticancer activities on tsFT210 and K562 cells of eighteen compounds were examined and their minimum inhibitory concentrations were assayed with the multiple dilution method. Labdane-type diterpenes 1-6 dramatically induced apoptosis at high concentrations while at lower concentrations mainly inhibited cell cycle progression at the GO/G1 phase both on tsFT210 and K562 cells. Flavonoids obtained in the present paper inhibited cell cycle progression of tsFT210 cells at the G2/M phase in a dose-dependent manner except for 10 and 13 inducing apoptosis on tsFT210 cells. In contrast, they mainly induced apoptosis on K562 cells. Lignans and other compounds possessed the activities of inhibiting cell cycle progression, inducing apoptosis and cytotoxicity. Flow cytometric investigations resulted in the conclusion of action features of eighteen compounds on tsFT210 and K562 cells and further demonstrated that these compounds exert their anti-proliferative effects on tsFT210 and K562 cells through inhibiting cell cycle, inducing apoptosis and/or toxicity.We discovered compound 9 (vitexicarpin) exhibited strong anticancer activity and its MIC value for inhibiting cell cycle of tsFT210 cells at G2/M phase is 0.04 jug/ml (0.1 uM). The inhibition was in dose and time dependent manners, moreover, its action pattern was similar to that of taxol on tsFT210 cells with greater efficacy than taxol. Because of its strong activity and high content in the title plant, the biological investigation of vitexicarpin was undertaken with particular attention to the anticancer activity on human tumor, K562 cells.Inhibitory effect of vitexicarpin on the proliferation of K562 cells was evaluated by SRB method. Flow cytometric...
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