Ras同源基因家族成员工基因在胃癌细胞中下调核因子-κB信号转导通路转录活性

The transcription activity of NF-κB signal pathway down regulated by Ras homolog gene family member I in gastriccancercell

目的研究Ras同源基因家族成员I（ARHI）基因与NF-κB之间的相互关系以及在胃癌发生发展中的可能机制。方法利用前期构建的pIRES2-EGFP—ARHI重组质粒和实验室保存的NF-κB报告基因质粒共转人胚胎肾293T细胞，根据荧光素酶反应测定NF-κB转录激活能力。通过siRNA方法干扰胃癌MKN-28细胞株ARHI的表达，Western印迹法检测其NF-κB磷酸化水平以及细胞核内NF-κB的变化情况。结果使293T细胞中ARHI过表达可以明显下调NF-κB的转录激活能力；在MKN-28细胞株中抑制ARHI表达，可使NF-κB磷酸化水平及细胞核内NF-κB蛋白水平均明显上调。结论ARHI可以下调NF-κB的转录激活能力，且能使胃癌细胞株中NF-κB的磷酸化降低、减少入核从而发挥抑癌作用。

Objective To investigate the relation between aplysia Ras homolog I （ARH I ） gene and NF-κB, and explore the possible mechanism in gastric cancer pathogenesis and development. Methods Human embryonic kidney cell line 293T ceils were co-transfeeted with pre-constructed pIRES2-EGFP-ARH I plasmid and NF-κB lueiferase reporterplasmid. The activity of NF-κB transcription was determined according to luciferase reaction. The expression of ARH I in MKN-28 cells was interfered by siRNA. The phosphorylation level of NF-κB and the changes of NF-κB expression in nuclear was detected by Western blot. Results The activity of NF-κB transcription was significantly down-regulated by ARH I overexpressing in 293T cells. In MKN-28 cell line, the phosphorylation level of NF-xB and its expression in nuclear at protein level was significantly up regulated. Conclusions The activity of NF-κB transcription can be down-regulated by ARHI , and which may reduce the phosphorylation level of NF-κB, and restrict it from entering the nucleus, and thus play a role in tumor suppression.