Effect of staurosporine on cycle human gastric cancer cell

AIM:To study the effect of staurosporine (ST) on the cell cycle of human gastric cancer cell lines MGC803 and SGC7901. METHODS:Cell proliferation was evaluated by trypan blue dye exclusion method.Apoptotic morphology was observed under a transmission electron microscope.Changes of cell cycle and apoptotic peaks of cells were determined by flow cytometry.Expression of p21 WAF1 gene was examined using immunohistochemistry and RT-PCR. RESULTS:The growth of MGC803 and SGC7901 cells was inhibited by ST.The inhibitory concentrations against 50% cells (IC 50 ) at 24 h and 48 h were 54 ng/ml and 23 ng/ml for MGC803, and 61 ng/ml and 37 ng/ml for SGC7901.Typical apoptotic bodies and apoptotic peaks were observed 24 h after cells were treated wth ST at a concentration of 200 ng/ml.The percentage of cells at G 0 /G 1 phase was decreased and that of cells at G 2 /M was increased significantly in the group treated wth ST at the concentrations of 40 ng/ml, 60 ng/ml, 100 ng/ml for 24 h, compared with the control group (P<0.01).The expression levels of p21 WAF1 gene in both MGC803 and SGC7901 cells were markedly up-regulated after treatment with ST.CONCLUSION: ST can cause arrest of gastric cancer cells at G 2 /M phase, which may be one of the mechanisms that inhibit cell proliferation and cause apoptosis in these cells.Effect of ST on cells at G 2 /M phase may be attributed to the up-regulattion of p21 WAF1 gene.