Study for the aim of gene therapy of nasopharyngeal carcinoma

鼻咽癌（NPC）是一种发病率具有明显地域和人群差异的上皮性肿瘤，血清学证据表明鼻咽癌与eb病毒（EBV）有关，并通过鼻咽癌细胞中EBVDNA和eb编码rna的检测证实了这种关系。而鼻咽癌是一种高度转移癌，其与EBV的相关性已得到证实。潜伏膜蛋白1 （Latent membrane protein 1, LMP1）是EBV潜伏感染时表达的一种膜蛋白，被认为是EBV的致癌蛋白。基质金属蛋白酶9 （Matrix metalloproteinase 9, MMP9）是MMP家族中的一种，可降解细胞外基质的主要成分iv型胶原，被认为在肿瘤的侵袭和转移中起着至关重要的作用。虽然有报道称MMP9在多种癌症中表达，但尚未发表有关NPC的报道。我们在体外细胞株中发现LMP1诱导MMP9，提示EBV的LMP1可能通过诱导MMP9参与鼻咽癌的转移和肿瘤发生。免疫组化检测38个npc切片中LMP1和MMP9的表达，并统计分析两者之间的关系。我们还分析了这些蛋白与临床特征的关系。结果表明，LMP1和MMP9蛋白主要在癌巢中免疫定位。MMP9的表达与LMP1的表达呈显著正相关。MMP9的表达与淋巴结转移相关。我们还发现LMP1通过激活核因子(NF) κ B和激活蛋白(AP)-1来增强MMP9的表达。因此，我们在体外测试了LMP1对MMP9的上调是否与肿瘤细胞侵袭性增强有关。我们还检测了阿司匹林和水杨酸钠是否能降低裸鼠肿瘤的侵袭性，以及LMP1是否能提高MMP9的表达。稳定表达LMP1的C33A细胞与载体转染的C33A细胞相比，MMP9的表达增加，通过重组基底膜的侵袭能力增强。阿司匹林和水杨酸钠抑制了表达lmp1的C33A细胞的侵袭性，并在酶谱分析中抑制了lmp1诱导的MMP9表达，在CAT报告基因检测中抑制了lmp1诱导的MMP9启动子活性。阿司匹林对NF- κ B活性的抑制作用可归因于对l-κ B激酶活性的抑制。最后，在裸鼠中生长的稳定表达LMP1的载体转染的C33A细胞衍生的肿瘤与载体转染的C33A细胞衍生的肿瘤相比，显示出更高的MMP9水平。这种增强被用阿司匹林治疗的小鼠所抑制。这些结果提示阿司匹林可能通过抑制MMP-9抑制表达LMP1的ebv相关肿瘤的侵袭和转移。少

Nasopharyngeal carcinoma (NPC), an epithelial tumor which is characterized by marked geographic and population differences in incidence, is found to be associated with Epstein-Barr virus (EBV) by serologic evidence, and the relationship was confirmed by the detection of EBVDNA and EB-encoded RNAs in NPC cells. While, NPC is highly metastatic carcinoma whose consistent associated with EBV has been established. Latent membrane protein 1 (LMP1), an EBV membrane protein expressed in latent infection is considered to be the EBV oncoprotein. Matrix metalloproteinase 9 (MMP9), one of the MMP families, degrades Type IVcollagen, a major 4 component of extracellural matrix and is believed to be crucial for cancer invasion and metastasis. Although MMP9 is reported to be expressed in a variety of cancers, no reports concerning NPC have been published. We have shown that LMP1 induces MMP9 in vitro cell line, which suggests the possibility of mechanism in which LMP1 of EBV contributes to the metasta … More sis and tumorgenesis of NPC by the induction of MMP9. Then the expression of LMP1 and MMP9 were immunohistochemically examined in 38 NPCs sections, and the relation of these proteins was statistically analyzed. We also analyzed the association of these proteins with clinical features. As results, both LMP1 and MMP9 proteins were predominantly immunolocalized in cancer nests. The expression of MMP9 showed a significant positive correlation with the expression of LMP1. Also the expression of MMP9 correlated with lymphnode metastasis.We also demonstrated that LMP1 enhances MMP9 expression by activation of nuclear factor ( NF) κ B and activator protein (AP)-1 . We therefore tested whether upregulation of MMP9 by LMP1 could be correlated with enhanced invasiveness of tumor cells in vitro. Whether aspirin and sodium salicylate could reduce invasiveness and whether LMP1 could enhance MMP9 expression in tumors grown in nude mice were also tested. C33A cells stably expressing LMP1 had increased expression of MMP9 and showed greater invasion through reconstituted basement membrane compared with vector-transfected C33A cells. Treatment with aspirin and sodium salicylate inhibited invasiveness of the LMP1-expressing C33A cells and suppressed both the LMP1-induced MMP9expewssion in zymographic analyses and LMP1-induced MMP9 promoter activity in CAT reporter assays. The inhibitory effect of aspirin on NF- κ B activity was attributable to the inhibition of l-κ B kinase activity. Finally, tumors derived from vector-transfected C33A cells stably expressing LMP1 grown in nude mice showed enhanced MMP9 levels compared with tumors derived from vector-trancfected C33A cells. This enhancement was inhibited by treatment of the mice with aspirin. These results suggest that aspirin may be able to suppress invasion and metastasis of EBV-associated tumors that express LMP1 by suppression of MMP-9. Less