Anti-tumor Action Of The Extract Of Fagopyrum Cymosum(Trev)Meisn And Its Mechnism

Fagopyrum cymosum (Trev.) Mein. Is a novel antineoplastic flowering herb. To further investigate the Anti-tumor effect of the extract of Fagopyrum cymosum(Trev.)Meisn and its mechanism, we isolated six extracts-Frl, Fr2, Fr3, Fr4, Fr5, Fr6 from rootin of Fagopyrum cymosum(Trev. )Mein and investigated their antiproliferative effects on Si 80 in mice. The result showed that Fr4 could significantly inhibit the growth of S 180 in vivo. Then we tested the antitumor action of Fr4 and its mechanism more deeply in this paper. The transplantable models of 5180, H22 and Lewis in mice were established to investigate the inhibitory effects of Fr4 against tumor.The results demonstrated that Fr4 could inhibite the growth of the tumors tested In mice.The rate of tumore inhibition against Si 80, 1122 and Lewis cancers were from 34.7% to 54.2% at th Fr4 concentration of 400mgIkg.d. But Fr4 couldn抰 prolong the life span of mice caring S 180. Cytotoxicity of Fr4 on six cell lines including K562, HL-60, B16, SW116O, BGC-823 and 786-B was dertermined with an MTT assay. The results showed that Fr4 had a prominent cytotoxity on K562 and HL-60 cell lines, with 1C50 values of 165 ii g/ml and 115 ii gIml respectively. To study the apoptosis-inducing effect of Fr4 on human leukemia HL-60 cells, morphologic changes were examined under light and electron microscopes. Flow cytometry assays and DNA gel electrophoresis were used to analyze DNA fragmentations. Treated with Fr4 for 24h at the concentration of 6Omg/L, l2Omg/L, 240mg/L, K562 and HL-60 were induced to apoptosis. And their morphological and biochemical changes were revealed by the following parameters: 1 )typical apoptotic morphology, such as chromatin condensation and formation of apoptotic bodies; 2)DNA fragmentation, the biochemical III M~L~ hail marker of apoptosis; 3)detection of hypodiploid population by flow cytometry analysis.The population o fapoptotic cells in HL-60 in the presence of 200mg/L, 400mg/L, 800mg/L of Fr4 were 50.9%, 55.4%, 59.7%. Further study with PCR-ELISA revealed a pronounced inhibition of telomerase activies of HL-60 at the concentration of 6Omg/L, l2Omg/L, 240mg/L, and the values of A were 0.53, 0.47, 0.28 respectively, compared with the control (the value of A was 0.73). To assess the effect of Fr4 on the migration of B 1 6-BL6 mouse melanoma cells in vitro, Transwell room model was used. The result showed that Fr4 could inhibite the lomotive potential of B 1 6-BL6 cells. The rate of inhibitory was 46.8 at the concentration of 240mg/L. To further evaluate the effect of Fr4 on the invasiveness and metastasis of tumor cells, we to analyze the expressin of MMIP- 9 ,TIMP- 1, and VEGF in Lewis cancer tissue with immunohistochemical technique. Then it was investigated that the expression of MMP-9 and VEGF was declined in the mice groups treated with Fr4 200mgIkg.d, 400mg/kg.d, 800mg/kg.d for seven days. In conclusion, Fr4 has a significant antitumor effect in vivo and vitro. The possible mechanism of those effects maybe associate with inducing apoptosis and downregulating telomerase activies of HL-60. Futhermore, Fr4 may have potential anti-invasion and anti-metastasis action against tumor cells.