Expression of Glycoprotein B (gB) Correlates With Poor Prognosis in Nasopharyngeal Carcinoma.

The Epstein-Barr virus (EBV) has two life cycles: latent and lytic. Previously, the latent cycle had been considered more relevant to EBV-associated epithelial malignancies, including nasopharyngeal carcinoma (NPC), whereas the lytic cycle, which ultimately leads to the death of host cells, had not been considered. However, recent studies have revealed that abortive lytic infections, in which the lytic cycle halts midway, avoids host cell death and contributes to tumorigenesis and tumor growth. However, the progression of the lytic cycle in NPC and its association with viral replication remain unclear. This study aimed to perform morphological analyses of EBV-positive NPC cell lines and clinical NPC biopsy samples using transmission electron microscopy, NanoSuit-correlative light and electron microscopy, and scanning ion conductance microscopy. Virion-like particles were observed in lytically induced EBV-positive NPC cell lines using time-lapse imaging to capture their release. These particles were also detected in clinical NPC samples using electron microscopy. Immunohistochemical analysis with the glycoprotein B (gB) antibody revealed a strong association between gB expression and poor prognosis. In conclusion, lytic infections with EBV replication occur in NPC, and the frequency of EBV replication is significantly associated with poor prognosis.