Inhibitory Effect of Berbamine on Proliferation of UMR-106 Rat Osteosarcoma Cells

Objective: To explore the inhibitory effect of berbamine on the proliferation of UMR-106 rat osteosarcoma cells and its possible mechanism in vitro. Methods: UMR-106 cells were cultured with different concentrations of berbamine (0, 2, 4, 8, 16 and 32 mg/L) for 24, 48 and 72 h, respectively. The proliferation was colorimetrically assayed by MTT. UMR-106 cells were interfered with different concentrations of berbamine (0, 4, 8 and 16 mg/L) for 24 h, and the morphological changes of UMR-106 cells were observed by laser confocal scan microscope after Hoechst 33258 staining. The apoptotic rates were detected by flow cytometry (FCM)using Annexin V/PI staining. The cell cycle was detected by FCM using PI staining. Results: Berbamine could obviously inhibit the proliferation of UMR-106 cells in a dose-dependent manner (P 0.01). The IC50 values at 24, 48 and 72 h were 24.69, 8.03 and 3.54 mg/L, respectively. There were nuclear condensation and apoptotic body in berbamine treated group. Apoptotic rates were (1.64±0.29)%,(3.58±0.31)%,(6.27±0.47)% and (11.27±1.09)% in control group and berbamine treated group (after 4, 8 and 16 mg/L treatment),respectively. There was a significant difference in apoptotic rate between berbamine treated group and control group (P 0.01). Meanwhile, berbamine can induce cell necrosis. In addition, berbamine significantly increased the percentages of G0/G1 phase and decreased S phase of cells and G2/M phase compared with those of control group (P 0.01). Conclusion: Berbamine can inhibit the proliferation of UMR-106 cells in vitro, which may be related to the cell apoptosis, necrosis and G0/G1 phase arrest.