EBV-encoded LMP1 increases nuclear β-catenin accumulation and its transcriptional activity in nasopharyngeal carcinoma

This paper aimed to study whether Epstein-Barr virus-encoded latent membrane protein 1 (LMP1) regulates beta-catenin signaling pathway in nasopharyngeal carcinoma (NPC). Western blotting, immunofluorescence, luciferase reporter assay, co-immunoprecipitation assay, and immunohistochemistry staining were used. LMP1 increased beta-catenin transcriptional activity in NPC cell lines. The upregulation of beta-catenin transcriptional activity induced by LMP1 was much higher in poorly differentiated NPC cell line CNE2 than that in well-differentiated NPC cell line CNE1. Immunofluorescence staining and Western blotting also showed that LMP1 increased nuclear beta-catenin accumulation in NPC cell lines. Moreover, LMP1 expression was closely related to abnormal beta-catenin expression in NPC tissues by immunohistochemistry. LMP1 may be involved in nasopharyngeal carcinogenesis via beta-catenin signaling pathway.