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Different ethnic groups with a high human leukocyte antigen (HLA)-A11 prevalence have been shown to experience a high rate of Epstein-Barr virus (EBV) infection, EBV-associated malignancies, and Epstein-Barr nuclear antigen (EBNA)-4 mutations. The epitopes 399-408 and 416-424 of EBNA-4 are major antigenic epitopes that elicit an HLA-A11 cytotoxic T lymphocyte (CTL) response to EBV infection. Mutations selectively involving one or more nucleotide residues in these epitopes affect the antigenicity of EBNA-4, because the mutant EBV strains are not recognized by the HLA-A11-restricted CTLs. To investigate these mutations in common EBV-associated malignancies occurring in different populations, we studied the mutation rate of epitopes 399-408 and 416-424 of EBNA-4 in 25 cases of EBV-associated Hodgkin's disease (HD), nine cases of AIDS-related non-Hodgkin's lymphoma, and 37 cases of EBV-associated gastric carcinoma (GC) from the United States, Brazil, and Japan. We found one or more mutations in these two epitopes in 50% (6/12) of United States HD, 15% (2/13) of Brazilian HD, 50% (6/12) United States GC and 28% (7/25) Japanese GC, and 22% (2/9) of United States AIDS-lymphoma. Similar mutations were found in 30% (3/10) of United States reactive, 0% (0/6) of Brazilian reactive, and 25% (2/8) Japanese reactive tissues. The most frequent amino acid substitutions were virtually identical to those seen in previously reported isolates from EBV-associated nasopharyngeal carcinomas and Burkitt's lymphomas occurring in high prevalence HLA-A11 regions. However, only 2/28 (7%) mutations occurred in HLA-A11-positive patients. Our studies suggest that: 1) EBNA-4 mutations are a common phenomenon in EBV-associated HD, GC, and AIDS-lymphoma; 2) the mutation rate does not vary in these geographic areas and ethnic groups; 3) EBNA-4 mutations in EBV-associated United States and Brazilian HD, United States and Japanese GC, and United States AIDS lymphomas are not related to patients' HLA-A11 status.

We examined the types of Epstein-Barr virus-associated nuclear antigen-1 (EBNA-1) gene carboxy (C)-terminal mutations occurring in Hodgkin's disease (HD) and reactive tissues from two different geographic regions. Previously reported EBNA-1 C-terminal region amino acid sequence variants, based on the amino acid at codon 487, include Prototype (P)-ala, which is found in the B95.8-derived prototype virus, P-thr, Variant (V)-leu, V-val, and V-pro. Using polymerase chain reaction (PCR) to amplify portions of the EBNA-1 gene, followed by DNA sequencing, we found a single EBNA-1 gene sequence variant in each tissue, whether reactive or neoplastic and whether from Brazil or the United States. Variant EBNA-1 gene sequences were more common in both neoplastic and non-neoplastic tissues from different geographic areas than the so-called prototype sequence. In the 17 Brazilian HD cases, 4 cases had P-thr variants and 13 had V-leu variants. In the six reactive tissues from Brazil, one had a P-ala variant, two had P-thr variants, and three had V-leu variants. In the 12 American HD cases, 2 had P-ala variants, 6 had P-thr variants, and 4 had V-leu variants. The 11 American reactive tissues included 2 P-ala variants, 5 P-thr variants, and 4 V-leu variants. In both countries, there were similar variant EBNA-1 sequences present in normal tissues and HD cases. Compared with the P-ala and P-thr cases, the V-leu cases were more likely to have the 30-bp latent membrane protein 1 (LMP1) gene deletion (P = 0.0075). In addition, cases of HD with the V-leu were statistically associated with a substitution of asparagine for glutamine at codon 322 of the C-terminal portion of the LMP1 gene. Our results suggest that any variation in EBNA-1 gene sequence is caused by a polymorphism present in pre-existing viral strains in the underlying population, and not a mutation occurring during oncogenesis.

A 30-basepair (bp) deletion in the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene has been reported in nasopharyngeal carcinoma and EBV-associated malignant lymphomas. Prior studies have found the deletion in about 10% to 28% of cases of Hodgkin's disease (HD), particularly in cases with aggressive histology. We studied the prevalence of 30-bp LMP1 gene deletion in EBV-positive HD in the United States (US) (12 cases) and Brazil (26 cases) with comparison to reactive lymphoid tissues (21 cases) and HD without EBV-positive Reed-Sternberg cells (15 cases). We studied the status of the LMP1 gene by Southern blot hybridization of polymerase chain reaction (PCR) products obtained after amplification with primers spanning the site of the deletion. We also performed EBV typing, EBER1 in situ hybridization, and LMP1 protein immunohistochemistry. EBV was detected in 12/26 (46%) cases of HD from the US and 26/27 (96%) cases of Brazilian HD. The 30-bp LMP1 gene deletion was observed in 4/12 (33%) cases of EBV-positive HD from US, and 12/26 (46%) cases of Brazilian EBV-positive HD, including 3 cases of type B EBV, as compared with 12/21 (57%) reactive lymphoid tissues and 9/15 (60%) cases of EBV-negative HD. US and Brazilian HD showed a higher prevalence of the 30-bp LMP1 gene deletion, compared with studies of others. The unexpected finding of high incidence of 30-bp deletion in LMP1 gene in reactive lymphoid tissue and HD without EBV-positive Reed-Sternberg cells suggests that this deletion may not be relevant to HD pathogenesis in most cases.

A 61-year-old man with acquired immunodeficiency syndrome (AIDS) sought care because of the onset of progressive dysphagia. He was found to have a perforated, fungating esophageal mass. The combined histologic and immunologic findings were diagnostic of Hodgkin's disease, nodular sclerosis type, lymphocyte-depleted variant, arising in the esophagus. The Reed-Sternberg cells and mononuclear variants were positive for Epstein-Barr virus (EBV) latent membrane protein (LMP1) and EBV RNA. Occasional small lymphoid cells were also positive for EBV RNA. Polymerase chain reaction studies demonstrated the presence of EBV type A without deletion of the EBV LMP1 gene. Other authors have reported an increased frequency of type B EBV and deletion of the EBV LMP1 gene in cases of human immunodeficiency virus-associated Hodgkin's disease. Hodgkin's disease arising in the esophagus is rare in immunocompetent patients. However, in the presence of AIDS, Hodgkin's disease should be considered in the differential diagnosis of patients with signs or symptoms of esophageal disease.

Although numerous studies have demonstrated increased expression of p53 protein in the Reed-Sternberg cells of Hodgkin's disease, little data exist as to whether mutations of the p53 gene is a common occurrence in this neoplasm. Using a microdissection technique coupled with PCR, single-strand conformation analysis, and DNA sequencing, we studied 23 cases of Hodgkin's disease for mutations within exons 5 to 8 of the p53 gene. We found seven mutations within six cases; six were missense mutations. An identical missense mutation was found in three cases (codon 243, methionine to isoleucine), and another identical missense mutation was found in an additional two cases (codon 204, glutamic acid to lysine). Verification of the mutations was accomplished either by direct Southern blotting of PCR-amplified p53 exon products from re-extracted DNA or by hybridization of cloned PCR-amplified p53 exon products from re-extracted DNA with a mutant-specific oligonucleotide. There was no good correlation between the presence of p53 mutations and the level of p53 protein expression, which was found to be overexpressed in all cases, the level of MDM2 protein expression, or the proliferation rate as determined by K-67 antibody. None of the cases with p53 mutation had evidence of Epstein-Barr virus within the Reed-Sternberg cells, as compared with 7 of 17 of the other cases (p < 0.06). These results suggest that p53 mutation may represent an important mechanism in the pathogenesis of Hodgkin's disease, and this mechanism may be independent of Epstein-Barr virus.

Tissues obtained from 14 patients with multiple anatomic sites involved by Hodgkin's disease were studied for Epstein-Barr virus (EBV) using in situ hybridization for EBV-encoded RNA (EBER) 1 and immunohistochemical methods for EBV latent membrane protein (LMP) expression. Each patient in this study had two to five separately involved anatomic sites, and all biopsy sites, a total of 43 specimens, were analyzed for EBV. EBV was detected in 6 of 14 (42.8%) patients with Hodgkin's disease, including 5 of 11 (45.4%) with nodular sclerosis and 1 of 3 (33%) with mixed cellularity. In these six patients, all biopsy sites were positive for both EBER1 and LMP. In the EBV-positive cases were analyzed the 3'-end of the EBV LMP1 gene in al sites of disease using polymerase chain reaction. In three patients all sites of disease had a 30-base pair deletion. In two patients, there was discordance between sites of disease, with LMP1 gene deletions in some sites and other sites with the LMP1 gene in the germline configuration. The results of this study demonstrate that EBV, when found in Hodgkin's disease, is detectable in all anatomic sites involved. The presence of the same 30-base pair deletion in the EBV LMP1 gene in all sites of disease in three patients suggests that the deletion occurred before dissemination and that all sites are clonally related. However, the discordance between anatomic sites in two patients suggests that LMP1 gene deletion may also occur as a later event, after dissemination. These results lend further support to the hypothesis that EBV plays a role in the pathogenesis of a subset of cases of Hodgkin's disease.

The Epstein-Barr virus (EBV) has been implicated in the pathogenesis of Hodgkin's disease, with an frequency of 15 to 50% in the immunocompetent host. We studied 12 formalin-fixed, paraffin-embedded cases of Hodgkin's disease occurring in human immunodeficiency virus-infected individuals to determine the frequency of EBV in Hodgkin's disease from this population. EBV DNA-RNA in situ hybridization was performed using a 30-base biotinylated anti-sense oligonucleotide complementary to the EBER1 gene of EBV. EBV RNA was found in the Reed-Sternberg cells and variants in 11 of 12 cases. Double-labeling studies confirmed the presence of EBV RNA in CD15-expressing Hodgkin's cells in all 11 cases, although rare B lymphocytes coexpressing EBV RNA and CD20 were also noted in these cases. The Hodgkin's cells in all 11 EBER-positive cases expressed latent membrane protein. The one case negative for EBV RNA showed the histology of nodular, lymphocyte predominance, a subtype thought to be distinct from other types of Hodgkin's disease.

The Epstein-Barr virus (EBV) has been implicated in the pathogenesis of Hodgkin's disease (HD). This study was undertaken to determine whether the association of EBV with HD showed geographical variation, as in Burkitt's lymphoma. We studied 32 formalin-fixed, paraffin-embedded cases of HD occurring in Peru. EBV DNA-RNA in situ hybridization was performed using a 30-base biotinylated antisense oligonucleotide complementary to the EBER1 gene of EBV. EBV immunohistochemistry was also performed, using a monoclonal antibody (MoAb) to the latent membrane protein (LMP1) of EBV. Identification of the precise cellular subset staining with EBV was accomplished via double-labeling with MoAbs directed against Reed-Sternberg cells (LeuM1/CD15) and B cells (L26/CD20). EBV RNA was identified in all or virtually all of the Reed-Sternberg cells and variants in 30 of the 32 (94%) cases of HD by in situ hybridization. LMP1 expression was identified in 83% of the EBER1-positive cases. Double-labeling studies confirmed the localization of EBV RNA to CD15-expressing Hodgkin's cells. This study found an extremely high prevalence of EBV in Peruvian HD, in contrast to the much lower percentage of EBV-associated cases of HD occurring in "Western" patients.

The techniques of immunohistochemistry and in situ hybridization were applied to 10 formalin- or B5-fixed, paraffin-embedded cases of nodular lymphocyte-predominant Hodgkin's disease to determine whether lymphohistiocytic (L&H) cells contain any detectable amount of immunoglobulin light chain protein or messenger RNA. None of the cases studied demonstrated any detectable amount of either kappa or lambda light chain mRNA within L&H cells or Reed-Sternberg cells despite positive labeling of plasma cells, immunoblasts, and germinal center cells. Polyclonal kappa light chain antibody studies showed positive staining of L&H cells in seven cases, including three costaining with polyclonal lambda light chain antibody. Monoclonal kappa and lambda light chain antibody studies, however, showed no staining of L&H cells despite positive staining of immunoblasts and plasma cells. It is suggested that L&H cells do not synthesize appreciable amounts of light chain immunoglobulin protein and are not closely related to reactive immunoblasts or germinal center cells.

The pathogenesis of Reed-Sternberg cells and variants (RS-H cells) found in rare cases of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is unknown. We studied 13 such cases by immunohistochemistry and in situ hybridization for identification of Epstein-Barr virus (EBV) RNA. The RS-H cells in five cases expressed the B-lineage marker CD20 and were negative for CD15. In two cases, the RS-H cells showed expression of both CD20 and CD15, whereas in another six cases, the cells were positive for CD15 but negative for CD20. Three of the cases expressing CD15 showed subsequent evidence of disseminated Hodgkin's disease. Regardless of the phenotype or clinical behavior, the RS-H cells in 12 of 13 cases were found to contain EBV RNA by in situ hybridization, but the surrounding neoplastic lymphocytes were invariably negative for EBV RNA. It is suggested that EBV has an important role in the pathogenesis of the RS-H cells in these rare cases.

The authors studied typical Hodgkin's disease along with the nodular, lymphocyte predominance subtype by both the polymerase chain reaction (PCR) and in situ hybridization for evidence of the Epstein-Barr virus (EBV). By PCR, EBV DNA was detected in 12/23 cases of typical Hodgkin's disease and 2/13 cases of the nodular, lymphocyte predominance subtype. EBV RNA was detected by in situ hybridization studies within Reed-Sternberg cells and variants in 11/23 cases of typical Hodgkin's disease and 0/13 cases of nodular, lymphocyte predominance Hodgkin's disease. Other cells positive for EBV, identified as both B and T cells in double-labeling immunohistochemical/in situ hybridization studies, were found in 20/23 cases of typical Hodgkin's disease, 9/13 cases of nodular, lymphocyte predominance Hodgkin's disease, 4/6 cases of progressive transformation of germinal centers, and 7/10 normal lymphoid tissues. It is concluded that EBV is significantly associated with Reed-Sternberg cells in approximately one-half cases of typical Hodgkin's disease but not in the nodular, lymphocyte predominance subtype. EBV-infected B and T cells are also present in a majority of cases of Hodgkin's disease as well as in reactive conditions.