Huang Wei, Yu Li-Fen, Zhong Jie, Wu Wei, Zhu Jia-Ying, Jiang Feng-Xiang, Wu Yun-Lin
Department of Gastroenterology, Ruijin Hospital, Jiaotong University School of Medicine, Shanghai 200025, China.
Dig Dis Sci. 2009 Oct;54(10):2056-62. doi: 10.1007/s10620-008-0617-z. Epub 2008 Dec 11.
The expression of matrix metalloproteinase-2 (MMP2) has been linked with tumor invasion, angiogenesis, and metastasis. It has been reported that angiotensin II (Ang II) can induce MMP2 expression in gastric cancer cells. However, the molecular basis for Ang II regulates MMP2 expression in gastric cancer cells remains unclear. The aim of our study is to explore whether angiotensin II could induce MMP2 expression mediated through the Stat signaling pathway and its potential mechanism. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-binding assays was employed to determine the DNA-STAT binding activity. MMP2 and VEGF expression was analyzed with real-time PCR and Western blots. To examine the role of Stat3 in angiotensin II-induced MMP2 expression, A JAK-specific inhibitor and AG490 were used. Angiotensin II activated STAT-DNA binding activity in dose-dependent manners in gastric cancer cells. AG490 markedly inhibited angiotensin II-induced Stat3 activation and the expression of MMP2 and VEGF in gastric cancer cells. These results indicate that Stat3 may at least in part mediate angiotensin II-induced MMP2 mRNA expression in human gastric cancer cells. The activation of the JAK/Stat3 signaling pathway plays an important role in the progression of gastric cancer and that blockade of JAK/Stat3 signals may provide a novel therapeutic strategy for gastric cancer.
基质金属蛋白酶-2(MMP2)的表达与肿瘤侵袭、血管生成和转移有关。据报道,血管紧张素II(Ang II)可诱导胃癌细胞中MMP2的表达。然而,Ang II调节胃癌细胞中MMP2表达的分子基础仍不清楚。我们研究的目的是探讨血管紧张素II是否能通过Stat信号通路介导诱导MMP2表达及其潜在机制。采用电泳迁移率变动分析(EMSA)和染色质免疫沉淀(ChIP)结合分析来确定DNA-STAT结合活性。通过实时PCR和蛋白质免疫印迹分析MMP2和VEGF的表达。为了研究Stat3在血管紧张素II诱导的MMP2表达中的作用,使用了一种JAK特异性抑制剂和AG490。血管紧张素II在胃癌细胞中以剂量依赖性方式激活STAT-DNA结合活性。AG490显著抑制血管紧张素II诱导的Stat3激活以及胃癌细胞中MMP2和VEGF的表达。这些结果表明,Stat3可能至少部分介导血管紧张素II诱导的人胃癌细胞中MMP2 mRNA的表达。JAK/Stat3信号通路的激活在胃癌进展中起重要作用,阻断JAK/Stat3信号可能为胃癌提供一种新的治疗策略。