Effect of genistein on proliferation and cell cycles of gastric cancer cells

Abstract

Objective To investigate the inhibitory effect of histidine protein kinase inhibitor genistein on human gastric cancer cell line MGC- 803, and its effect on the expression of Cyclin B1 and cell cycle. Methods MGG803 cells were cultured. Methyl thiazol tetrazolium(MTT)assay was used to examine the inhibitory effect of genistein in MGC803 cells. Three concentrations of genistein were used in MTT assay: 170, 200, and 220μmol/L.Western blotting was used to detect the expression of Cyclin B1 and CDK1. Results With the increase of genistein concent ration and prolongation of time, from 24 to 72 h, MTT showed the inhibitory rate of proliferation of MGC- 803 cells increased in a dose- and time- dependent manner(P<0.01). Flow cytometry indicated that as compared with control group, the S percentage in 24,48 and 72 h genistein groups was(24.37±3.25)%,(27.11± 2.82)% and(28.20±4.17)% respectively vs.(12.35±2.62)%(P<0.01),and G2/M percentage was (23.11±3.31)%,(27.41±2.70)% and(35.61±2.67)% respectively vs.(9.65±3.62)%(P< 0.01). When MGC- 803 cells were treated with genistein for 72 h,the cell rate at G2/M were the most significantly increased. Western blot showed that, with the increase genistein concent ration(170,200 and 220μmmol/L)and prolongation of time(24,48 and 72 h),the expression of protein Cyclin B1 and CDK1 gradually decreased. There are significant differences by compared with the control group (P<0.01). Conclusion Genistein can decrease the expression of Cyclin B1 and CDK1 in MGC- 803 cells, and also could inhibit cell cycle and proliferation of MGC803 cells. Key words: Gastric carcinoma; Genistein; Cell cyle