Abstract: BACKGROUND ＆ AIM: To investigate the anti-tumor activity of extract from Periploca Sepium Bge (PSBE) and to study its probable mechanisms. MATERIALS AND METHODS: The growth-inhibitory effect of ethanol extract from Periploca sepium bge (PSBEE) and water extract from Periploca sepium Bge (PSBWE) on MCF-7,TE-13,QG56,SMMC7721,T24,Hela,K562 tumor cell lines were examined by using MTT assay, the change of cell cycle and the induction of apoptosis were analyzed with flow cytometry. RESULTS: Both PSBEE and PSBWE could significantly inhibit the proliferation of tumor cell lines, the effect was dose-dependent, PSBEE (IC50<10 μg/ml) was more effective than PSBWE (IC50<40 μg/ml). PSBEE could arrest the cell cycle at G0/G1 phase and induce apoptosis in MCF-7 cells in a time-dependent manner. The proportion of tumor cells in the G0/G1 phase increased after treatment with 10 μg/ml PSBEE for 24 hours, the apoptotic rate reached 13.54％±2.12％ after 48 h. CONCLUSION: Cell growth in vitro was inhibited significanttly by extract from Periploca sepium Bge, PSBEE might exert its anti-tumor activity by blocking the cell cycle and inducing apoptosis of tumor cells.

Key words: periploca sepium bge, anti-tumor, cell proliferation, cell cycle, cell apoptosis