SPLUNC1 reduces the inflammatory response of nasopharyngeal carcinoma cells infected with the EB virus by inhibiting the TLR9/NF-κB pathway
SPLUNC1 reduces the inflammatory response of nasopharyngeal carcinoma cells infected with the EB virus by inhibiting the TLR9/NF-κB pathway
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SPLUNC1通过抑制TLR9/NF-κB通路来降低感染EB病毒的鼻咽癌细胞的炎症反应。
DOI：
10.3892/or.2015.3913
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发表时间：
2015-06-01
期刊：
影响因子：
4.2
通讯作者：
Li, Xiaoling
中科院分区：
文献类型：
--
作者：
Ou, Chunlin;Sun, Zhenqiang;Li, Xiaoling
研究表明，天然免疫相关蛋白短腭、肺和鼻上皮克隆1 （SPLUNC1）在鼻咽上皮组织中具有抗肿瘤作用。然而，SPLUNC1在eb病毒（EBV）相关鼻咽癌（NPC）炎症微环境中抑瘤作用的具体机制尚不清楚。本研究旨在探讨SPLUNC1如何通过调节toll样受体（TLR）9/NF-κB信号通路，降低感染EBV的鼻咽癌细胞的炎症反应。免疫组化和免疫印迹检测发现，SPLUNC1蛋白在鼻咽癌上皮组织/细胞中低表达或阴性表达，而在正常鼻咽癌上皮组织/细胞中呈阳性表达；这种表达模式与TLR9相反。低分化的HNE2细胞系通过“细胞对细胞”接触法将EBV感染转移的效率最高。ebv感染HNE2细胞组TLR9/NF-κB信号通路相关因子（TLR9、CD14、MyD88、IKK、p - k βα、P-NF-κB和NF-κB）的表达明显升高。感染EBV后，HNE2细胞组炎症因子IL-6、IL-8、IL-1β、TNF-α水平高于未感染细胞组（P<0.05）；同时，EBV感染后，HNE2/SPLUNC1细胞组TLR9/NF-κB通路相关蛋白及炎症因子IL-6、IL-8、IL-1β、TNF-α的表达水平低于HNE2/Vector细胞组（P<0.05）。EBV-DNA直接转染后，HNE2细胞组细胞因子TLR9、IL-6、IL-8、IL-1β和TNF-α mRNA表达水平显著高于NP69细胞组（P<0.05）。这些细胞因子在HNE2/SPLUNC1细胞组中的表达水平明显低于HNE2/Vector细胞组（P<0.05）。上述结果提示，EBV感染鼻咽癌细胞可激活TLR9/NF-κB信号通路，促进炎症因子的释放，从而增强炎症反应，而SPLUNC1可通过调控TLR9/NF-κB信号通路，控制肿瘤炎症微环境，从而减弱EBV感染鼻咽癌细胞诱导的炎症反应。
Studies indicate that the natural immune-related protein short palate, lung, and nasal epithelium clone 1 (SPLUNC1) plays an antitumor role in nasopharyngeal epithelial tissue. However, the detailed mechanism of the tumor-suppressor effect of SPLUNC1 in the inflammatory microenvironment of Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) remains elusive. The aim of the present study was to explore how SPLUNC1 reduces the inflammatory response of NPC cells infected with EBV by regulating the Toll-like receptor (TLR)9/NF-κB signaling pathway. As detected by immunohistochemistry and western blotting, SPLUNC1 protein expression exhibited low or negative expression in the NPC epithelial samples/cells, while it demonstrated positive expression in normal nasopharyngeal epithelial tissues/cells; this pattern of expression was the contrary to that of TLR9. The poorly differentiated HNE2 cell line had the highest efficiency of transfer of infection with EBV by 'cell-to-cell' contact method. The group of EBV-infected HNE2 cells showed significantly higher activation of the expression of TLR9/NF-κB signaling pathway-associated factors (TLR9, CD14, MyD88, IKK, P-IKβα, P-NF-κB and NF-κB). The levels of inflammatory cytokines IL-6, IL-8, IL-1β and TNF-α in the HNE2 cell group after EBV infection were higher than these levels in the uninfected cell group (P<0.05); Meanwhile, after EBV infection, the expression levels of TLR9/NF-κB pathway associated-protein and inflammatory cytokines IL-6, IL-8, IL-1β and TNF-α in the HNE2/SPLUNC1 cell group were lower than these levels in the HNE2/Vector cell group (P<0.05). After EBV-DNA direct transfection, cytokine mRNA expression levels of TLR9, IL-6, IL-8, IL-1β and TNF-α in the HNE2 cell group were significantly higher than these levels in the NP69 cell group (P<0.05). The expression levels of these cytokines in the HNE2/SPLUNC1 cell group were obviously lower than these levels in the HNE2/Vector cell group (P<0.05). These results suggest that EBV infection of NPC cells can activate the TLR9/NF-κB signaling pathway, promote the release of inflammatory cytokines and consequently enhance the inflammatory response, while SPLUNC1 can weaken the inflammatory response induced by EBV infection in NPC cells through the regulation of the TLR9/NF-κB signaling pathway and control of the tumor inflammatory microenvironment.