High mobility group box 1 (HMGB1) is upregulated by the Epstein-Barr virus infection and promotes the proliferation of human nasopharyngeal carcinoma cells

Abstract

Conclusion: The current study confirmed the significant high mobility group box 1 (HMGB1) was promoted in human nasopharyngeal carcinoma (NPC) tissues by Epstein-Barr virus (EBV) infection, in association with the malignant status of NPC, and promoted the proliferation NPC cells RAGE-dependently. Objectives: The present study was to examine the association of HMGB1 over-expression in human NPC with the EBV-positivity and to determine the regulatory role of HMGB1 on the proliferation of NPC cells in vitro. Methods: Real-time PCR and Western blotting were utilized to examine the HMGB1 expression. EBV infection in CNE-2 cells was performed to investigate the HMGB1 promotion by EBV infection. RNA interference technology was utilized for the RAGE knockout. Results: It was demonstrated that HMGB1 was significantly higher in both mRNA and protein levels in the EBV-positive NPC tissues, in marked association with the malignant status of NPC, and with the LMP1 DNA level in EBV-positive NPC samples. In addition, the MTT assay, growth curve, and the colony forming assay confirmed the promotion by HMGB1 to the proliferation of CNE-2 cells, depending on RAGE.