中文摘要：

目的探讨氧化苦参碱（OXY）对人胃癌细胞株SGC7901增殖及调控PCNA的作用机制。方法以SGC7901为研究对象，用SRB法测定OXY的增殖抑制率；FCM测定细胞周期；QPCR检测PCNAmRNA的表达；Western blot方法检测OXY作用SGC7901后p38MAPK、p-p38MAPK、JNK、p-JNK、ERK、P-ERK信号通路蛋白的表达变化。结果OXY对SGC7901细胞增殖具有明显的抑制作用，FCM结果显示OXY组G1期的细胞均显著增加，s期细胞明显减少；与对照组比较，OXY组PCNAmRNA和蛋白表达显著下降（P〈0．05或〈0．01）；与对照组比较，OXY组p-ERK表达水平降低（P〈0．05），预防给予ERK抑制剂PD98059能进一步降低p-ERK表达（P〈0．01），其他蛋白表达均无明显变化。结论OXY通过抑制ERK磷酸化抑制胃癌SGC7901细胞PCNA表达，抑制细胞增殖。

英文摘要：

Objective To investigate the effects of oxymatrine （OXY） on the proliferation of human gastric cancer cell line （ SGC7901 ）, and to explore its action mechanism of regulating the expression of PCNA. Methods The inhibitory rate of cell proliferation of SGC7901 was detected by SRB, and cell cycle was detected by flow cytometry. The expressions of PCNA mRNA and protein were determined by QPCR, and the changes of signal pathway proteins including p38MAPK, p-p38MAPK, JNK, p-JNK, ERK, p-ERK after treated by OXY were detected by Western Blot. Results The cell proliferation of SGC7901 cell line was obviously inhibited by oxymatrine, and the examination results by flow cytometry showed that the cell number at G1 stage in OXY group was significantly increased,however,which was obviously decreased at S stage. As compared with those（ 1.12 ± 0.16,0.68 ±0.11 ）in control group, the expressions of PCNA mRNA and protein were significantly decreased in OXY group （0.32 ± 0.01,0.24±0. 03, P 〈 0.05 or P 〈 0.01 ）. As compared with that （0.76 ± 0.12） in control group, the expression of p-ERK was significantly decreased in OXY group（0.44 ± 0.05, P 〈 0.05）, furthermore, the preventive administration of ERK inhibitor-PD98059 could reduce the expression of p-ERK further. Conclusion Oxymatrine can inhibit proliferation of SGC7901 cells and can reduce the expressions of PCNA through inhibiting the phosphorylation of ERK.