免疫球蛋白kappa轻链基因在鼻咽癌中表达的初步研究

EXPRESSION OF IMMUNOGLUBULIN KAPPA LIGHT CHAIN IN NASOPHARYNGEAL CARCINOMA

目的：为了探讨Ｉｇκ是否参与了鼻咽癌的癌变过程及可能机制，对Ｉｇκ在鼻咽癌中的表达进行了研究，并初步探讨Ｉｇκ与ＥＢ病毒潜伏膜蛋白基因ＬＭＰ－１在鼻咽癌中的相关性。方法：分别运用原位杂交技术和免疫组化技术检测鼻咽癌活检组织中Ｉｇκ的ＲＮＡ和蛋白质水平的表达。Ｗｅｓｔｅｒｎ印迹分析两株鼻咽癌细胞系（ＣＮＥ１和ＣＮＥ－ＬＭＰ）ｋａｐｐａ蛋白的表达及强度差异。结果：原位杂交技术显示１００％（４２例／４２例）标本均有ｋａｐｐａ的表达：免疫组化和Ｗｅｓｔｅｒｎ印迹提示，ｋａｐｐａ蛋白表达在所有的鼻咽癌组织和鼻咽癌细胞系里，且表达的可能是游离型的ｋａｐｐａ轻链。在整合表达有ＬＭＰ的ＣＮＥ１－ＬＭＰ鼻咽癌细胞株，游离型ｋａｐｐａ的表达明显增强。结论：这些结果提示Ｉｇκ基因可能与鼻咽癌癌变过程相关。其致癌机制可能与它和ＥＢ病毒的ＬＭＰ有联系，这为阐明鼻咽癌癌变的分子机理提供了又一条有益的思路。

Objective:To present evidence that kappa light chain gene expresses in both cell lines and biopsies of NPC and to determine whether kappa gene is related with Epstein Barr virus latent membrane protein 1 (LMP 1) in nasopharyngeal carcinogenesis.Methods:Kappa light chain expressed in NPC was detected by in situ hybridization, immunochemistry and Western blot. Results: All the samples,including 10 cases of well differentiated and 32 cases of poorly differentiated nasopharyngeal carcinoma,expressed kappa RNA and all the cases (7 cases) showed weak signals in the immunochemical test with anti free kappa light chain antibody.In addition, NPC cell line which was transfected with Epstein Bar virus latent membrane protein (designated CNe LMP cell line) seemed to express higher level of kappa free light chain than that without LMP transfection (designated CNE1). Conclusion:Immunoglobulin kappa gene may be involved in carcinogenesis of nasopharyngeal carcinoma through cooperation with EBV LMP.Therefore,to some extent,our studies have provided another possible molecular mechanism for nasopharyngeal carcinogenesis.