Deletions within the LMP1 oncogene of Epstein-Barr virus are clustered in Hodgkin's disease and identical to those observed in nasopharyngeal carcinoma

Abstract

This study of 52 European patients with Hodgkin's disease (HD) expressing the latent membrane protein 1 (LMP1) oncogene within diagnostic Hodgkin and Reed-Sternberg (HRS) cells was performed to detect LMP1 isolates carrying deletions and to characterize them at a molecular and histologic level. Deletions were identified in 5 cases, clustered near the 3′ end of the LMP1 gene, and histologically associated with numerous HRS cells. DNA sequencing showed homology with the deletions seen in the Asian nasopharyngeal carcinoma (NPC) isolates CAO and 1510. Our findings suggest that partial deletions of the LMP1 oncogene, associated with aggressive behavior in NPC CAO and NPC 1510, occur at a particular localization and confer a proliferative phenotype to lymphoid cells in HD.

Comparative analysis of Epstein-Barr virus gene polymorphisms in nasal T/NK-cell lymphomas and normal nasal tissues: Implications on virus strain selection in malignancy

“…The presence of the del‐ LMP1 genotype, which was originally identified in NPC tissues, in lymphoid malignancies was first reported in a small proportion of European HD cases with histologically aggressive behaviour (Knecht et al, 1993). This association was subsequently extended to other EBV‐related lymphomas from different geographic regions.…”

“…cDNA (equivalent to 0.5 μg total RNA) of each case of nasal T/NK‐cell lymphoma, which was used for RT‐PCR analysis of EBV gene expression (Chiang et al, 1996), and 2 μg genomic DNA extracted from frozen tissues of each case of nasopharynx and nasal polyp served as templates for PCR amplification for 40 cycles at an annealing temperature of 56°C. A pair of primers of B95–8 coordinates 168390–168370 and 168075–168095, as described by Knecht et al (1993), was used. Amplified products were electrophoresed through 3% MetaPhor (FMC BioProducts, Rockland, ME) 1 × TAE agarose gel, which was Southern‐blotted by alkaline transfer and hybridised by a 5' end‐labelled internal oligonucleotide probe (B95–8 coordinates 168135–168115) to confirm the specificity.…”

“…The labelling mix consisted of deaza labelling mix‐dATP and [α‐ 35 S]dATPαS. Both non‐coding and coding strands were sequenced using MS7 (B95–8 coordinates 168200–168220) and MS1 (B95–8 coordinates 168358–168338) primers, respectively, as described by Knecht et al (1993), followed by electrophoresis through a 6% polyacrylamide gel containing 7M urea and autoradiography.…”

“…A specific LMP1 genotype which contains a 30‐bp deletion (and single‐base mutations) in the 3' C‐terminal region of the LMP1 gene (del‐ LMP1 ), with respect to the non‐deleted/wild type B95–8 (wt‐ LMP1 ) sequence, was first identified in genomic clones of a nude mouse‐propagated Chinese nasopharyngeal carcinoma (NPC), CAO (Hu et al, 1991), as well as a Taiwanese NPC tumour (clone 1510) (Chen et al, 1992). Subsequently, similar LMP1 deletion variants were found in 10% of European EBV‐associated Hodgkin's disease (HD) cases which showed histologically aggressive features (Knecht et al, 1993), 30% of Danish HD and infectious mononucleosis cases, 61% of Danish and all of 9 Malaysian peripheral T‐cell lymphomas (Sandvej et al, 1994), 100% of NPC and 86% of peripheral T‐cell lymphomas from Taiwan (Chang et al, 1995) and 20% of Burkitt's lymphomas (BLs) and 71% of aggressive non‐Hodgkin's lymphomas from the United States (Kingma et al, 1996). Of note, del‐ LMP1 genotypes, as in CAO ‐LMP1 and 1510 ‐LMP1, conferred higher tumorigenicity with respect to the non‐deleted prototype B95–8 LMP1, when transfectants carrying these genotypes were inoculated into SCID and nude mice, respectively (Hu et al, 1993; Chen et al, 1992).…”

Comparative analysis of NK/T‐cell lymphoma and peripheral T‐cell lymphoma in Korea: Clinicopathological correlations and analysis of EBV strain type and 30‐bp deletion variant LMP1

“…Several studies have revealed that the LMP1 protein of the 30‐bp deletion mutant (del) has a greater potential to transform established rodent fibroblasts and immortalize human keratinocytes in vitro 42 . One study reported on its association with cases of Hodgkin’s disease showing aggressive histology or behavior 43 . Based on these studies, high frequencies of del LMP1 might be expected in certain tumor groups, and del LMP1 may be a predictive factor of clinical outcome.…”