ABSTRACT
PURPOSE: To investigate whether non-Hodgkin's lymphoma of Korea is pathogenetically associated with Epstein-Barr virus (EBV). MATERIALS AND METHODS: We analyzed fifty nine paraffin-embedded tissue and 22 fresh frozen tissue samples from non-Hodgkin's lymphoma patients for the presence of EBV sequences by polymerase chain reactions (PCR), in situ hybridization (ISH) and assessed the clonality of EBV infected cells by Southern blot hybridization. RESULT: On ISH using oligonucleotide probes corresponding to EBV-encoded small RNAs (EBERs), 17 (28.8%) of 59 paraffin-embedded tissue samples showed positive hybridization signals localized over the nuclei of the tumor cells, but PCR using primers from Internal Repeat I or EBV-determined nuclear antigen 1 gene showed positive results in only 6 (10.2%) and 5 (8.5%) samples, respectively. ISH and PCR did not detect EBV sequences in 15 paraffin-embedded tissue samples of tuberculous lymphadenitis patients. In 22 fresh frozen tissue samples, PCR detected EBV sequences in three samples from peripheral T cell lymphoma (PTCL). In two of those three samples, Southern blot analysis showed that these viral DNAs were monoclonal and of latent form. CONCLUSION: Approximately 28.8% of non-Hodgkin's lymphoma were related to EBV in Korea. Monoclonality of those EBV DNAs implies that virus infection preceded malignant transformation, suggesting that EBV may play a role in lymphomagenesis.