TNF-α-induced cyclooxygenase-2 expression in human lung epithelial cells:: Involvement of the phospholipase C-γ2, protein kinase C-α, tyrosine kinase, NF-κB-inducing kinase, and I-κB kinase 1/2 pathway
TNF-α-induced cyclooxygenase-2 expression in human lung epithelial cells:: Involvement of the phospholipase C-γ2, protein kinase C-α, tyrosine kinase, NF-κB-inducing kinase, and I-κB kinase 1/2 pathway
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DOI：
10.4049/jimmunol.165.5.2719
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发表时间：
2000-09-01
影响因子：
4.4
通讯作者：
Chiu, KT
中科院分区：
文献类型：
--
作者：
Chen, CC;Sun, YT;Chiu, KT
肿瘤坏死因子-ru诱导NCI-H292上皮细胞环氧合酶-2(COX-2)表达和前列腺素E_2(PGE_2)的形成呈剂量和时间依赖性增加。免疫荧光染色显示COX-2表达于胞浆和核膜。酪氨酸激酶抑制剂(金雀异黄素或赫比霉素)或磷脂酶C抑制剂(U73122)可阻断肿瘤坏死因子-α诱导的COX-2表达，肿瘤坏死因子-α也可促进磷脂酰肌醇的水解和蛋白激酶C(PKC)的活性，两者均可被金雀异黄素或U73122所阻断，星形孢子素也可抑制肿瘤坏死因子-α诱导的反应。PRC激活剂12-O-十四酰佛波醇13-乙酸酯(TPA)也能刺激COX-2的表达，这种作用可被金雀异黄素或除草素抑制，而这种作用可被肿瘤坏死因子-α增强，而这些作用可被染料木素、U73122、星形孢子素或二硫代氨基甲酸吡咯烷抑制，TPA可刺激核因子-kappaB的DNA结合和COX-2启动子的活性，这些作用可被染料木素、除草霉素或吡咯烷二硫代氨基甲酸酯所抑制。磷脂酶C-Gamma2突变体可抑制肿瘤坏死因子-α诱导的COX-2启动子活性，但不能抑制TPA诱导的COX-2启动子活性，而PKC-α、核因子-kappaB诱导的激酶或I-kappaB(从核因子-kappaB解离的抑制蛋白)的显性-负性突变体可减弱这三种突变体诱导的COX-2启动子活性。这些结果表明，在NCI-H292上皮细胞中，肿瘤坏死因子-α和TPA都能刺激IKK活性，这些作用可被星形孢子素或赫比霉素抑制。肿瘤坏死因子-1-γ可能通过上游酪氨酸激酶激活磷脂酶C-γ2，诱导PKC-α和蛋白酪氨酸激酶的激活，从而激活COX-2启动子中的NF-kappaB、IKK1/2和NF-kappaB，进而启动COX-2的表达和PGE(2)的释放。
TNF-ru induced a dose- and time-dependent increase in cyclooxygenase-2 (COX-2) expression and PGE, formation in human NCI-H292 epithelial cells. Immunofluorescence staining demonstrated that COX-2 was expressed in cytosol and nuclear envelope. Tyrosine kinase inhibitors (genistein or herbimycin) or phosphoinositide-specific phospholipase C inhibitor (U73122) blocked TNF-alpha -induced COX-2 expression, TNF-alpha also stimulated phosphatidylinositol hydrolysis and protein kinase C (PKC) activity, and both were abolished by genistein or U73122, The PKC inhibitor, staurosporine, also inhibited TNF-alpha -induced response. The 12-O-tetradecanoylphorbol 13-acetate (TPA), a PRC activator, also stimulated COX-2 expression, this effect being inhibited by genistein or herbimycin, NF-kappaB DNA-protein binding and COX-2 promoter activity were enhanced by TNF-alpha, and these effects were inhibited by genistein, U73122, staurosporine, or pyrolidine dithiocarbamate, TPA stimulated both NF-kappaB DNA-protein binding and COX-2 promoter activity, these effects being inhibited by genistein, herbimycin, or pyrolidine dithiocarbamate. The TNF-alpha -induced, but not the TPA-induced, COX-2 promoter activity was inhibited by phospholipase C-gamma2 mutants, and the COX-2 promoter activity induced by either agent was attenuated by dominant-negative mutants of PKC-alpha, NF-kappaB-inducing kinase, or I-kappaB (inhibitory protein that dissociates from NF-kappaB) kinase (IKK)1 or 2, IKK activity was stimulated by both TNF-alpha and TPA, and these effects were inhibited by staurosporine or herbimycin, These results suggest that, in NCI-H292 epithelial cells, TNF-1 gamma might activate phospholipase C-gamma2 via an upstream tyrosine kinase to induce activation of PKC-alpha and protein tyrosine kinase, resulting In the activation of NF-kappaB-inducing kinase and IKK1/2, and NF-kappaB in the COX-2 promoter, then initiation of COX-2 expression and PGE(2) release.