Synergistic Effects Of TOR Combined With DDP Or EADM On Growth And Apoptosis In Human Lung Cancer Cell Lines

Objective: To study the effects of toremifene combined with cisplatin or epirubicin on human lung cancer cell lines A549 (p53-positive), HI299 (p5 3-negative) and its mechanisms .To evaluate the expression of p-gp in the two cell lines.Methods: Human lung adenocarcinoma cell lines A549 (p53-positive) and non-small cell lung cancer cell lines H1299 (p53-negative) are devided into blank group (culture),controul group (cells),experiment group (cells+ diffirent factors). Expriment group are devided into toremifene group, anti-tumor drugs group, combine group. Cell proliferation was evaluated by MTT assay. The methods of Annexin-v and PI combination labeling were used to measure the apoptosis. Distribution of cell cycle and rate of apoptosis were determined by flow cytometry. The expression of p-gp in the two cell lines were determined by flow cytometry.Results: Toremifene (20wmol/l) could inhibit the growth of A549 cells and H1299 cells directly. The IR (Inhibitory rate) of the low dose toremifene (5\10wmol/l) combined with anti-tumor drugs were higher than that of anti-tumor drugs alone.The inhibitory rate of the cell lines also increased with increases in the agents concentration. Toremifene and Its combination with cisplatin or epirubicin could induce A549 cells and HI299 cellsapoptosis markedly, "Sub-G^'phase peak occurred in flow cytometry.The ratio of apoptosis would increase with increases in the concentration of toremifene. Toremifene combined with cisplatin or epirubicin could couse A549 cells and H1299 cells cycle to change ,and would appear S phase decreasing as well as Go/Gi phase increasing . Go/Gi phase increasing and G2/M phase decreasing were acheieved in the treatment of A549 cells with toremifene alone,and the H1299 cells were blocked in Gz/M phase by toremifene.The expression level of p-gp of H1299 cells (44.9%) was higher than that of A549 cells (13.1%) .Conclusion: 1. The low dose toremifene combined with cisplatin or epirubicin show significant synergistic anti-tumor effects on A549 cells and H1299 cells. 2. Toremifene combined with cisplatin or epirubicin could cause A549 cells and HI299 cells cycle to change. Toremifene combined with cisplatin or epirubicin could induce A549 cells and H1299 cells apoptosis markedly. 3. The synergistic anti-tumor effects on A549 cells was higher that on H1299 cells. 4. The expression level of p-gp of H1299 cells was higher than that of A549 cells. 5. The mechanism of effects could be related with change of phase in cell cycles and apoptosis, which may involve a p53 gene dependent pathway.