Abstract: Objective: To study the influence of metformin and paclitaxel in the proliferation and apoptosis of human ovarian cancer SKOV3 cells in vitro, and to clarify the synergistic effect of metformin and paclitaxel. Methods: The ovarian cancer SKOV3 cells were divided into blank control group, different concentrations (0.01, 0.50, 1.00, 5.00, 10.00mmol·L^-1) of metformin groups and combined treatment groups(metformin combined with paclitaxel with different concentrations). The inhibitory rates of proliferation of SKOV3 cells after treated with different concentrations of metformin were detected by MTT method. The apoptotic rates of SKOV3 cells after treated with different concentrations of metformin were measured by flow cytometry. The inhibitory rates of proliferation of SKOV3 cells after treated with metformin and paclitaxel were determined by MTT method. Results: The MTT results showed that the inhibitory rates of proliferation of SKOV3 cells in different concentrations of metformin groups were increased in concentration-and time- dependent manner; there were significant differences compared with blank control group (P<0.05). The flow cytometry results showed that the apoptotic rates of SKOV3 cells in different concentrations of metformin groups were increased; compared with control group, with the increasing of concentrations of metformin, the apoptotic rates of SKOV3 cells in experimental groups 48 h after treatment were increased significantly (P<0.05); the percentages of SKOV3 cells in G₀/G₁ phase were decreased with the increasing of metformin concentrations(P<0.05) and the percentages of SKOV3 cells in G₂/M phase were increased(P<0.05). The MTT results showed that the inhibitory rate of proliferation of SKOV3 cells in 1.00 mmol·L^-1 metformin+paclitaxel group was higher than that in 0.50 mmol·L^-1 metformin+paclitaxel group was higher than that in 0.50 mmol·L^-1 metformin+paclitaxel group(P<0.05),and the inhibitory rates of proliferation of SKOV3 cells in combined treatment groups were higher than those in paclitaxel alone groups(P<0.05). Conclusion: Metformin inhibits the proliferation of ovarian cancer SKOV3 cells through the induction of apoptosis. Metformin can enhance the cell proliferation inhibition of paclitaxel on ovarian cancer SKOV3 cells. The combination of metformin and paclitaxel has a synergistic reaction on SKOV3 cells.

Key words: apoptosis, ovarian neoplasms, metformin, cell proliferation, paclitaxel