Reactive Oxygen Generated by NADPH Oxidase 1 (Nox1) Contributes to Cell Invasion by Regulating Matrix Metalloprotease-9 Production and Cell Migration
Reactive Oxygen Generated by NADPH Oxidase 1 (Nox1) Contributes to Cell Invasion by Regulating Matrix Metalloprotease-9 Production and Cell Migration
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DOI：
10.1074/jbc.m109.071779
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发表时间：
2010-02-12
影响因子：
4.8
通讯作者：
Kamata, Tohru
中科院分区：
文献类型：
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作者：
Shinohara, Masahiro;Adachi, Yoshifumi;Kamata, Tohru
活性氧产生酶Nox1在RAS癌基因转化表型中起中介作用，包括锚定非依赖性细胞生长、增强的血管生成和肿瘤形成。然而，关于Nox1信号是否调节细胞侵袭性的研究很少。在此，我们报道了在K-RAS转化的正常大鼠肾细胞中，细胞侵袭活性被增强，并通过将Nox1小干扰RNA(SiRNAs)导入细胞而被减弱。二苯基碘(DPI)或Nox1 siRNAs阻断K-RAS转化的正常大鼠肾细胞中基质金属蛋白酶-9在蛋白和mRNA水平的上调。此外，DPI和Nox1 siRNAs抑制了IKKα激酶的激活和I kappa Bα的降解，从而抑制了依赖于NF kappa B的基质金属蛋白酶-9启动子的活性。此外，表皮生长因子刺激的Caco-2细胞的迁移可被DPI和Nox1 siRNAs阻断，表明Nox1活性对表皮生长因子的运动作用是必需的。Nox1的这种作用是通过低分子蛋白酪氨酸磷酸酶-p190RhoGAP依赖的机制下调Rho活性而实现的。综上所述，我们的发现定义了NOX1产生的活性氧物种在细胞入侵过程中的中介作用，最显著的是金属蛋白酶的产生和细胞运动活性。
A mediating role of the reactive oxygen species-generating enzyme Nox1 has been suggested for Ras oncogene transformation phenotypes including anchorage-independent cell growth, augmented angiogenesis, and tumorigenesis. However, little is known about whether Nox1 signaling regulates cell invasiveness. Here, we report that the cell invasion activity was augmented in K-Ras-transformed normal rat kidney cells and attenuated by transfection of Nox1 small interference RNAs(siRNAs) into the cells. Diphenyleneiodonium (DPI) or Nox1 siRNAs blocked up-regulation of matrix metalloprotease-9 at both protein and mRNA levels in K-Ras-transformed normal rat kidney cells. Furthermore, DPI and Nox1 siRNAs inhibited the activation of IKK alpha kinase and the degradation of I kappa B alpha, suppressing the NF kappa B-dependent matrix metalloprotease-9 promoter activity. Additionally, epidermal growth factor-stimulated migration of CaCO-2 cells was abolished by DPI and Nox1 siRNAs, indicating the requirement of Nox1 activity for the motogenic effect of epidermal growth factor. This Nox1 action was mediated by down-regulation of the Rho activity through the low molecular weight protein-tyrosine phosphatase-p190RhoGAP-dependent mechanism. Taken together, our findings define a mediating role of Nox1-generated reactive oxygen species in cell invasion processes, most notably metalloprotease production and cell motile activity.