Molecular analysis of the inhibition of monocyte chemoattractant protein-1 gene expression by estrogens and xenoestrogens in MCF-7 cells
Molecular analysis of the inhibition of monocyte chemoattractant protein-1 gene expression by estrogens and xenoestrogens in MCF-7 cells
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DOI：
10.1210/en.141.1.50
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发表时间：
2000-01-01
期刊：
影响因子：
4.8
通讯作者：
Matsushima, K
中科院分区：
文献类型：
--
作者：
Inadera, H;Sekiya, T;Matsushima, K
异雌激素（Xenoestrogens，XEs）是一组具有类似雌激素作用的化学物质，可能对人类健康产生不良影响。这些化合物对细胞因子产生或免疫系统功能的影响尚不清楚。在这项研究中，我们研究了17 β-雌二醇（E-2）和XEs对趋化因子（趋化因子）产生的影响，并分析了分子机制。单核细胞趋化蛋白-1（MCP-1），也称为单核细胞趋化和活化因子，是趋化因子家族的一员，主要吸引血液单核细胞。人乳腺肿瘤细胞系MCF-7细胞响应白细胞介素-1 α（IL-1 α）产生大量MCP-1。向MCF-7细胞中添加E-2以剂量依赖性方式抑制MCP-1的产生。XEs、双酚A和NP也抑制MCP-1的产生，尽管效力比E-2低3-4个数量级。E-2、双酚A和NP抑制MCF-7细胞中MCP-1信使RNA的表达。在人MCP-1基因的启动子中已经鉴定了两个紧密定位的核因子-κ B位点A1和A2。含有该增强子区域的荧光素酶构建体（pGLM-ENH）被IL-1a激活，并且Al或A2位点处的突变导致IL-1a响应性的丧失。用E-2或XE处理显著降低IL-1 α诱导型pGLM-ENH荧光素酶活性。在电泳迁移率变动分析和超变动分析中，我们发现用E-2或XEs处理减少了IL-1 α诱导的与A1和A2探针的复合物形成，其经免疫化学鉴定由核因子-κ B、p50和p65组成。IL-1 α诱导的p50/c-Rel与A2探针的复合物也在较小程度上被E-2或XE处理降低。E-2和XE对MCP-1表达的影响似乎比这些试剂对荧光素酶测定中使用的启动子的影响显著得多，这表明E-2和XE涉及MCP-1基因启动子区的额外位点或MCP-1基因表达的转录后调节。这项工作代表了第一份报告，描述了通过抑制趋化因子的产生来调节免疫系统功能。
Xenoestrogens (XEs) are a diverse group of chemicals that mimic estrogenic actions and may have adverse effects on human health. The influence of these compounds on cytokine production or immune system function remains unclear. In this study we have examined the effects of 17 beta-estradiol (E-2) and XEs on chemoattractant cytokine (chemokine) production and analyzed the molecular mechanism. Monocyte chemoattractant protein-1 (MCP-1), also termed monocyte chemotactic and activating factor, is a member of the chemokine family and attracts mainly blood monocytes. Human mammary tumor cell Line MCF-7 cells produce a large quantity of MCP-1 in response to interleukin-1 alpha (IL-1 alpha). Addition of E-2 to MCF-7 cells inhibited MCP-1 production in a dose-dependent manner. XEs, bisphenol A, and NP also inhibited MCP-1 production, although the potency was 3-4 orders of magnitude lower than that of E-2. E-2, bisphenol A, and NP inhibited MCP-1 messenger RNA expression in MCF-7 cells. Two closely located nuclear factor-kappa B sites, Al and A2, have been identified in the promoter of the human MCP-1 gene. A luciferase construct containing this enhancer region (pGLM-ENH) was activated by IL-la, and a mutation at either the Al or A2 site resulted in a loss of IL-la responsiveness. Treatment with E-2 or XEs decreased the IL-la-inducible pGLM-ENH luciferase activity significantly. In an electrophoretic mobility shift assay and supershift analysis, we found that treatment with E-2 or XEs diminished the IL-1 alpha-induced complex formation with both Al and A2 probes, which was identified immunochemically to consist of nuclear factor-kappa B, p50, and p65. The IL-1 alpha-induced p50/c-Rel complex to the A2 probe was also, to a lesser extent, decreased by E-2 or XE treatment. The effects of E-2 and XEs on the expression of MCP-1 seem to be much more dramatic than the effects of these agents on the promoters used in the luciferase assay, suggesting the involvement of an additional site(s) of the promoter region of the MCP-1 gene or posttranscriptional regulation of MCP-1 gene expression by E-2 and XEs. This work represents the first report describing possible regulation of immune system function by XEs through inhibiting chemokine production.