木脂素对MGC-803胃癌细胞的抗增殖作用及其与细胞周期相关蛋白的相关性

目的]研究木脂素对MGC-803胃癌细胞的抗增殖作用及其与细胞周期相关蛋白之间的相关性．方法]采用MTT方法检测对照组和实验组各时间段的细胞生存率，利用流式细胞技术检测木脂素对细胞周期的影响，采用免疫细胞化学染色方法检测p53，CDK2，cyclinE及cyclinD1蛋白的表达．结果]MTT方法检测结果见，药物浓度为25μmol／L时实验组在24，48，72h的生存率分别为82．6％±2．7％，69．1％±4．5％，50．5％±1．7％，与对照组相比较差异均具有统计学意义（P〈0．01），并具有浓度依赖性．利用流式细胞仪检测细胞周期结果见，G1期细胞增多，S期及G2期细胞减少．免疫细胞化学染色结果见，在24，48，72h时实验组胃癌细胞突变型p53，cyclinD1，cyclinE和CDK2蛋白的阳性表达率与对照组相比较明显降低，各组间差异均具有统计学意义（P〈0．01）．结论]木脂素对MGC-803胃癌细胞具有明显的抗增殖作用，其机制之一与下调突变型p53，cyclinD1，cyclinE和CDK2蛋白的表达，阻止胃癌细胞从细胞周期G1期进入S期，从而抑制胃癌细胞DNA合成有关．

Anti-proliferative effects of the lignans to MGC-803 gastric cancer cell line and its correlation with cell cycle related protein

OBJECTIVE To study the anti-proliferative effects of the lignans to MGC-803 gastric cancer cell line and its correlation with cell cycle related protein. METHODS The time-dependent cell survival rate was detected in control group and experimental group by MTT assay, the effects of lignans on cell cycle by flow cytometry, and the expression of p53, CDK2, cyclin E and cyclin D1 protein by immunocytochemistry. RESULTS MTT assay： the cell survival rate in experimental group at 24 h, 48 h and 72 h was 82.6% ± 2.7%, 69.1% ± 4.5% and 50.5% ± 1.7%, respectively, when the concentration of lignans was 25 μmol/L, and the difference was significant as compared with control group （P 〈 0.01） and had concentration-dependent also. G1 phase cells increased, and S and G2 phase cells decreased. The positive expression rate of the mutant p53, cyclin D1, cyclin E and CDK2 protein was markedly decreased at 24h, 48h and 72h in experimental group as compared with control group, and the differences were significant （P%0.01）, respectively. CONCLUSION The lignans has marked antiproliferative effects to MGC-803 gastric cancer cell line, and one of its mechanisms may be related to the down-regulation of the expression of mutant p53, cyclin D1, cyclin E and CDK2 protein and prevent gastric cells from G1 phase to S phase, and consequently, inhibit the DNA synthesis of the gastric cancer cells.