健脾解毒方介导p38MAPK信号转导下调幽门螺杆菌诱导的胃癌细胞环氧合酶2启动子活性

Jianpi Jiedu Recipe Intervenes Signal Transduction of p38 Mitogen-activated Protein kinases and Inhibits Activity of Cyclooxygenase-2 Promoter Induced by Helicobacter pylori in Gastric Cancer Cell MKN45

目的:探讨幽门螺杆菌(Helicobacter pylori)对人胃癌MKN45细胞环氧合酶2(Cyclooxygenase-2,COX-2)启动子荧光素酶报告基因重组质粒(pGL3-Basic-COX-2-promoter)活性的影响和健脾解毒方对其的调控作用及可能的机制。方法:将构建的pGL3-Basic-COX-2-promoter转染MKN45细胞,观察H.pylori对其活性的影响。运用p38MAPK特异性抑制剂SB203580阻断p38MAPK信号通路,观察H.pylori对MKN45细胞COX-2启动子活性的影响。Western blot法检测健脾解毒方对H.pylori感染的MKN45细胞p38MAPK信号通路及其下游激活转录因子-2(ATF-2)表达的影响。结果:H.pylori可增加COX-2启动子活性;抑制p38MAPK信号通路后,COX-2启动子活性明显下调;健脾解毒方能够抑制H.pylori诱导的p38MAPK及ATF-)的活性。结论:H.pylori通过p38MAPK信号通路上调胃癌细胞COX-2启动子活性;健脾解毒方通过调控p38MAPK/ATF-2信号通路,抑制COX-2启动子活性,是其防治H.pylori诱发胃癌的机制之一。

Objective：To investigate the effect of Helicobacter pylori on pGL3-Basic-COX-2-promoter transcriptional activity in gastric cancer MKN45 cells and the regulatory mechanism of Jianpi Jiedu Recipe on COX-2 promoter transcriptional activity.Method：The recombinant vector pGL3-Basic-COX-2-promoter was transient co-transfected into MKN45 cells,then detected the effect of H.pylori on COX-2 promoter activity.The effect of H.pylori on COX-2 promoter activity in human gastric cancer cells after blocking p38MAPK signal transduction pathway with a specific inhibitor SB203580 was observed.The effect of Jianpi Jiedu Recipe on H.pylori-stimulated phosphorylation of p38MAPK and ATF-2,the downstream transcription factor of p38MAPK,was investigated.Result：H.pylori could increase COX-2 promoter activity.COX-2 promoter activity down-regulated significantly afterblocking p38MAPK signal transduction pathway.Jianpi Jiedu Recipe inhibited H.pylori-induced p38MAPK and ATF-2 activity.Conclusion：H.pylori infection increases COX-2 promoter transcriptional activity via p38MAPK signal transduction pathway,and Jianpi Jiedu Recipe inhibits H.pylori-induced COX-2 promoter transcriptional activity through regulating p38MAPK/ATF-2 signal transduction pathway,which may be one of the mechanisms of prevention and treatment of gastric cancer.