Epstein-Barr virus latent membrane protein-1 (LMP-1) expression in oral squamous cell carcinoma.

OBJECTIVES Epstein-Barr virus (EBV) is frequently associated with malignant cell transformation through the action of the oncoprotein latent membrane protein-1 (LMP-1). The present study aimed to determine the presence of EBV in oral squamous cell carcinomas (OSCCs) and the expression of LMP-1 in neoplastic cells of EBV-positive OSCCs. STUDY DESIGN/METHODS In a retrospective study of 78 OSCCs, we investigated the presence of the DNA of EBV by polymerase chain reaction, the expression of the oncoprotein LMP-1 by immunohistochemistry, and the presence of EBV-encoded RNA (EBER) by in situ hybridization. RESULTS EBV DNA was detected in 19.2% of the cases. Expression of LMP-1 in neoplastic cells was found in 85.7% of the EBV-positive OSCCs. EBV presence was significantly more frequent (P <.05) in OSCCs localized on the lateral tongue. EBV-positive OSCCs more frequently presented (P <.05) greater nuclear atypia. CONCLUSION EBV can appear in latent form in OSCC and express its main oncoprotein, LMP-1.