Background & objective: Latent membrane protein 1 (LMP1) of Epstein-Barr (EB) virus is an important oncogene. Fascin is an actin cross-linking protein involved in cell migration and adhesion. Phosphorylated signal transducer and activator of transcription 3 (pStat3) is a member of STATs family, which is closely related to tumorigenesis. This study was to investigate expressions of LMP1, Fascin and pStat3 in nasopharyngeal carcinoma (NPC) tissues and lymph node metastases of NPC, thus to explore their correlations to the initiation and progression of NPC.
Methods: Expressions of EBV-encoded small RNA (EBER), LMP1, Fascin, pStat3, p53, Ki-67 and Bcl-2 were detected in 43 NPC tissues (21 with and 22 without lymph node metastases) and 21 corresponding lymph node metastases using in situ hybridization or immunohistochemistry (IHC). Data were statistically analyzed. Expressions of pStat3 and Fascin were measured in the NPC cell line CNE1 transfected with LMP1-expressing plasmid using Western blot.
Results: Positive EBER expression was detected in all 43 NPC tissues and 21 lymph node metastases in NPC. The expression rates of LMP1, Fascin, pStat3, p53, Ki-67, and Bcl-2 were 69.8% (30/43), 93.0% (40/43), 72.1% (31/43), 90.7% (39/43), 88.4% (38/43) and 88.4% (38/43)in 43 NPC tissues, respectively. LMP1 expression was positively correlated with the expression level of Fascin, pStat3, p53, Ki-67 and Bcl-2 in 43 NPC cases(P < 0.05). LMP1 was found in 10 out of 21 (46.7%) lymph node metastases in NPC. In addition, LMP1 expression dramatically increased pStat3 and Fascin in CNE1 cells.
Conclusions: LMP1 is expressed in lymph node metastatases in NPC. The expression of LMP1 is positively correlated with Fascin, pStat3 and the proliferation index of tumor cells. Moreover, LMP1 up-regulates pStat3 and Fascin in NPC cells.