RELATIONSHIP BETWEEN THE EXPRESSIONS OF LMP1 AND E-CADHERIN/β-CATENIN IN NASOPHARYNGEAL CARCINOMA

Objective:To compare the expression of Epstein-Barr virus encoded LMP1 and E-cadherin/β-catenin in primary and metastatic nasopharyngeal carcinoma (NPC) for the purpose of understanding their relationship. Methods: Twenty-two pairs of biopsies taken from the nasopharynx and cervical lymph node(s) of the same patient with nasopharyngeal carcinoma were collected. The expression of LMP1, E-cadherin and β-catenin was observed on immunostained slides using LSAB method. Results:The expression rate of LMP1 in the 22 metastatic tumors (86.36%, 19/22) was significantly higher than that in the 22 primary growths (68.18%, 15/22), P<0.05. The mean expression percentages of E-cadherin and β-catenin in metastatic tumors (50.11%(22.53% and 66.36(21.05%, respectively) were significantly lower than those in primary growths (71.52(24.34 % and 79.40%(15.05%, respectively), P<0.05. There was a positive correlation between the expressions of E-cadherin and β-catenin either in primary growths or metastatic tumors. Conclusion: The LMP1 is more likely to be expressed in metastatic neoplastic cells of NPC than in primary carcinoma cells, and on the contrary the expression of E-cadherin/β-catenin in metastatic cells was decreased. Accordingly, the LMP1 might have the ability to downregulate the expression of E-cadherin/β- catenin, resulting in enhancement of the invasive capacity of metastatic NPC cells.