An investigation on the antitumor activities of Euphorbia neriifolia

• Main Authors: Chien-Fu Chen, 陳建甫
• Other Authors: Eric I-chian Li
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/94272886960431431075

碩士 === 國立成功大學 === 藥理學研究所 === 94 === Euphorbia neriifolia is a succulent and cactus-like shrub which has been used as a folk medicine in Taiwan for the treatment of various diseases including cancer. This study aims at investigating the antitumor activities of E. neriifolia. We performed various antitumor experiments in vitro and in vivo to evaluate its potential antitumor activities. The dry powder of whole plant was extracted with 50% ethanol and then partitioned with ethyl acetate and water to yield an ethyl acetate extract (11%) and aqueous extract (1%). The ethyl acetate extract ,abbreviated as EN-EAE, showed significant cytotoxicities against some cell lines, including Lewis lung carcinoma (LLC), B16F10 melanoma and SW480 human colon adeno-carcinoma in a dose-dependent manner. In vivo tumor model using implanted LLC revealed that the EN-EAE extract significantly reduced the tumor size when C57/BL6 mice were treated with EN-EAE i.p.q.d. at a dose of 10 and 20 mg/kg. Flow cytometry analysis revealed that EN-EAE induced SW480 tumor cells to undergo cell cycle arrest in the G2/M phase within 24 hrs and increased cell population at sub-G1 phase in a dose and time-dependent manner. DNA fragmentation assay and Hoechst 33258 nuclear staining confirmed that cytotoxicity of EN-EAE was due to apoptosis. Rat aortic ring assay indicated 125 µg/ml EN-EAE also inhibited the outgrowth of endothelial cell from rat arotic ring and further micro-vessel web formation. In addition, EN-EAE at 80 µg/ml had no effect on the proliferation of PC3 cells in culture but suppressed the cell movement as assayed by the wound healing experiment. The suppression is echoed by its inhibition of PC3 cell migration initiated by chemoattractant in the Boyden chamber assay. Gelatin zymography assay showed 80 µg/ml EN-EAE reduced the secretion of matrix metalloproteinase-9 (MMP-9) from PC3 cells. The results combined indicate that EN-EAE possesses antitumor activities. E. neriifolia is worthy of further investigation to obtain its active constituent and to study its possible molecular mechanism of action.