Effect of staurosporine on cell cycle of human colon cancer cells

[Objective] To investigate the effect of PKC inhibitor staurosporine (STS) on the inhibition of proliferation, the induction of apoptosis, and the change of cell cycle in human colon cancer line COLO 320. [Methods] COLO320 cells were treated by PKC inhibitor Staurosporine(STS) for 24 hours, the inhibition rates of cell proliferation were evaluated by MTT assay. The apoptotic peaks of the cells and the changes of cell cycle were analyzed using flow cytometry. [Results] Staurosporine inhibited cell growth of COLO320, IC50 of 24 hours was 55 ng/mL. COLO320 cells were treated by STS at the concentrations of 20,60 100 ng/ml for 24 hours, the percentages of G0/G1 phage were(47.3%±1.53%), (49.5%±1.54%), (51.6%±2.12%), respectively(57.1%±1.89%) in 100 ng/mL PMA, (50.6%±1.69%) in control group, the percentages of G2/M phage were (30.45%±1.32%), (34.5%±1.23%), (37.7%±1.82%), respectively(24.7%±0.35%) in 100 ng/mL PMA, (1.85%±0.78%) in control group. Compared with the control group and PMA treated group, the percentages of G0/G1 phage of COLO320 decreased (P 0.05) and that of G2/M cells increased significantly in the STS treated group (P 0.01). Treated by STS at the different concentrations, the apoptotic peaks and typical apoptotic bodies were observed. [Conclusion] STS significantly inhibits the proliferation, induces apoptosis of COLO320 cell and induces G2/M phase arrest by inhibiting the activation of PKC.