Expression of c-myc and bcl-2 oncogene products in Reed-Sternberg cells independent of presence of Epstein-Barr virus.

AIMS: To evaluate the expression of c-myc and bcl-2 oncogene products in Reed-Sternberg cells in Hodgkin's disease, especially in relation to Epstein-Barr virus infection and expression of EBV encoded latent membrane protein (LMP). METHODS: Tissues from 33 cases of Hodgkin's disease were studied for the presence of EBV DNA by polymerase chain reaction (PCR) and DNA in situ hybridisation (DISH), for the presence of EBER-1 and EBER-2 EBV RNA by RNA in situ hybridisation (RISH); and for the presence of LMP, bcl-2, and c-myc proteins by immunohistochemical staining. RESULTS: A substantial number of Reed-Sternberg cells expressed bcl-2 in 20 of 29 (69%) and c-myc in 30 of 32 (94%) Hodgkin's disease samples. In 18 of the 25 (72%) cases Reed-Sternberg cells expressed both oncogene products. Of these 18 cases, 10 (56%) were EBV-PCR positive; eight (44%) were EBV-PCR negative. CONCLUSIONS: Reed-Sternberg cells in Hodgkin's disease frequently express both bcl-2 and c-myc oncogene products, suggesting that these oncogenes may act in concert in the pathogenesis of the disease. Moreover, the expression of c-myc and bcl-2 proteins in Reed-Sternberg cells is independent of EBV and LMP status.     

T cell-rich B cell lymphoma bearing Epstein-Barr virus in tumor cells: A case of IBL-T-like lesion following Lennert's lesion

A case of T cell-rich B cell lymphoma (TCRBCL) with Epstein-Barr virus (EBV) infection in tumor cells is reported. A 50 year old male developed right cervical lymph node swelling in July 1988. Initial biopsy in April 1989 demonstrated many scattered Hodgkinoid atypical cells with Lennert's lesion. After partial remission following chemotherapy, the lymph nodes enlarged again, and a second biopsy in February 1991 showed an IBL-T-like lesion. Only a small number of Hodgkinoid atypical cells were still observed. After apparently, complete remission, the lesion soon recurred and the patient died in November 1992. Immunohistochemically the Hodgkinoid cells were positive for L26, but negative for LN2, LN3, UCHL-1, MT1, lysozyme, Ber-H2 and Leu-M1. Reactivity for immunoglobulins showed falsepositive because of poly-clonal staining. IgH monoclonality was detected by the poly-merase chain reaction method in the first biopsied specimen, and by Southern blotting in the second biopsied snap-frozen specimen. Monoclonal TCRβ rearrangement was not detected. The Hodgkinoid atypical cells were positive for EBVencoding RNA by in situ hybridization, and LMP-1 by immunostaining. Occasionally, EBV-bearing immunoblastic, medium sized, or small lymphocytic cells were also observed. This case indicates the possibility that EBV is related to the pathogenesis of TCRBCL.     

bcl-2 proto-oncogene and Epstein–Barr virus latent membrane protein-1 expression in AIDS-related lymphoma

The expression of bcl-2 protein and Epstein–Barr virus (EBV) latent membrane protein 1 (LMP-1) was investigated in 18 cases of lymphoma occurring in the acquired immunodeficiency syndrome (AIDS). EBV small RNAs were detectable in tumour cells in all cases by in situ hybridization with EBER oligonucleotides. LMP-1 expression was detected in 61% of the cases, and 55% were positive for bcl-2. Dual expression of LMP-1 and bcl-2 was found in 8/18 (44%) cases, while five cases (28%) expressed either LMP-1 or bcl-2 and five expressed neither. Thus, there was an inconsistent relationship between the presence of EBV and the expression of bcl-2. One LMP-1 negative case was found to express bcl-2 in reactive lymphocytes but not in lymphoma cells. No clinical features were found to correlate statistically with LMP-1 or bcl-2 expression in the tumour cells. However, CD4 counts at diagnosis were significantly lower in bcl-2 positive cases ( P < 0.05). The respective roles of EBV LMP-1 and the expression of bcl-2 in lymphogenesis in AIDS patients remains complex and is not yet fully understood.     

bcl-2 expression by multicolor flow cytometric analysis assists in the diagnosis of follicular lymphoma in lymph node and bone marrow

The expression of bcl-2, CD10, and CD20 was examined by multicolor flow cytometry in 78 samples including lymph node or other tissue biopsy specimens containing follicular lymphoma (FL; n = 17), reactive hyperplasia (RH; n = 28), or other malignant lymphomas (n = 20), as well as bone marrow aspirates (n = 13). The presence of CD10+ cells with high bcl-2 expression predicted the presence of FL rather than RH with a positive predictive value of 100% and negative predictive value of 96%. CD10+ cells with high bcl-2 expression also were found in a subset of diffuse large B-cell lymphomas and were otherwise rare in other types of malignant lymphoma. In contrast with immunohistochemical studies, a reduced but apparently measurable level of bcl-2 was present in benign follicular center cells. Hematogones showed lower bcl-2 levels than did FL cells in the bone marrow, and neutrophils were bcl-2-. Measurement of bcl-2 expression levels by multiparameter flow cytometry offers a rapid, quantitative assessment that may assist in the diagnosis of FL in lymph nodes or bone marrow, even when other CD10+ cells or admixed normal B cells are present.     

肺癌患者EBV感染、LMP1和Bcl-2表达状况的研究

目的 研究肺癌患者癌组织中EB病毒（Epstein-Barr virus,EBV）感染、EBV潜伏膜蛋白1 （latent membrane protein 1,LMP1）和B淋巴细胞瘤/白血病-2基因（B cell lymphoma/Leukemia-2,Bcl-2）的表达及意义。方法 采用原位杂交法（in situ hybridization,ISH）检测肺癌组织标本中EBV编码的小RNA（ EBER1）,免疫组化法（immunohistochemistry,IHC）检测Bcl-2和LMP1的表达,以GD-6多媒体彩色病理图像分析系统进行形态学定量,以图像的平均面积（average area,AA）和积分吸光度（Integral optical density,IA）表示表达量的多少。结果 在108例肺癌癌组织中36例EBV阳性,阳性率为33.3％;LMP1阳性表达7例,阳性率6.5％。EBV阳性肺癌组中Bcl-2表达显著高于EBV阴性组,其AA分别为58014.23±6918.45和38156.22±4096.79,其IA分别为11.00±1.48和8.03±0.78,差异有统计学意义。进一步分析LMPI和Bcl-2表达的关系,可见LMP1可使Bcl-2表达率增加,但定性分析和定量分析差异无统计学意义。结论 EBV感染使Bcl-2表达增加,可能在肺癌的发生发展中有一定作用。在肺癌组织中EBV可能不是通过LMP1来影响Bcl-2的表达,具体机制有待进一步研究。     

Transformation of hairy cell leukemia to high-grade lymphoma: a case report and review of the literature

The coexistence of hairy cell leukemia (HCL) and non-Hodgkin's lymphoma is extremely rare. In the few reports demonstrating such coexistence, the relationship between the 2 entities was mostly inconclusive. We report a case of HCL that transformed to large cell lymphoma. This case has been followed for more than 4 years with immunohistochemical, flow cytometric, and molecular genetic studies on multiple bone marrow biopsy specimens, a splenectomy specimen, and a lymph node biopsy. In our case, the immunophenotype and tartrate-resistant acid phosphatase stain confirmed that the large cell lymphoma was of HCL origin. The markedly increased Ki-67 staining (proliferation fraction) in the lymph node biopsy specimen compared to the earlier splenectomy specimen indicated the transformation of a low-grade leukemia to a high-grade lymphoma. The overexpression of p53 in the lymph node implies that p53 mutation was probably involved in the pathogenesis of HCL transformation.     

Immunohistochemical detection of p53 and Bcl-2 proteins in Hashimoto's thyroiditis and primary thyroid lymphomas.

AIMS--To investigate whether immunohistochemical staining using p53 and/or bcl-2 distinguishes between florid Hashimoto's thyroiditis and low grade mucosa associated lymphoid tissue (MALT) lymphoma of the thyroid. METHODS--Ten cases of Hashimoto's thyroiditis and eight of primary thyroid lymphoma were stained with monoclonal antibodies directed against p53 and bcl-2. RESULTS--In Hashimoto's thyroiditis most small lymphoid cells in mantle zones, within the thyroid parenchyma and in lymphoepithelial lesions expressed bcl-2 protein. Very occasional centroblasts in reactive germinal centres were positive for p53, but all other lymphoid cells from cases of Hashimoto's disease were negative for p53. In diffuse, low grade lymphomas bcl-2 protein was uniformly expressed by most tumour cells. However, low grade lymphomas with a follicular pattern did not express bcl-2. The diffuse, low grade lymphomas were negative for p53, while occasional larger cells in the follicular subtype were positive. Both high grade lymphomas were bcl-2 negative but strongly p53 positive. CONCLUSIONS--This study indicates that there is an inverse correlation between p53 and bcl-2 immunostaining in thyroid lymphomas (low grade lymphomas: bcl-2 positive, p53 negative; high grade lymphomas: bcl-2 negative, p53 positive). Furthermore, immunohistochemical staining for bcl-2 and p53 proteins does not distinguish florid Hashimoto's thyroiditis from diffuse, low grade thyroid lymphoma.     

Epstein-Barr virus infection and its gene expression in gastric lymphoma of mucosa-associated lymphoid tissue

The role of Epstein-Barr virus (EBV) in the pathogenesis of gastric lymphoma of mucosa-associated lymphoid tissue (MALT) has not been well understood. The aim of the study was to investigate EBV infection and its gene expression in this tumor in order to understand its role in the pathogenesis. EBV infection was screened by in situ hybridization for EBV-encoded nonpolyadenylated RNA (EBER ISH) in 79 cases of gastric MALT lymphoma of nonimmunocompromised patients. The expression of EBV proteins [LMP1 (latent membrane protein 1), EBNA2 (EBV nuclear antigen 2), ZEBRA (switch protein encoded by BZLF1 gene)] was studied by immunohistochemistry in EBER-positive cases. EBV was detected with EBER ISH in 15 (19%) of the 79 cases. EBV was found in virtually all tumor cells in 2 cases of high-grade MALT lymphoma (2.5%) (EBV-associated), and was found only in occasional large or small lymphoid cells in 13 cases (16.5%). False positive EBER signal was detected in the mucinous glandular epithelial cells of gastric antrum with FITC-labeled oligonucleotide probe but not with digoxigenin or ³⁵S-labeled riboprobes. Type II latency (EBER+LMP1+ EBNA2-) was detected in both EBV-associated cases. Type III latency (EBER+LMP1+EBNA2+) was also identified in one EBV-associated case besides latency II. Double labeling showed coexpression of LMP1 and EBNA2 in a small number of tumor cells, indicating the presence of type III latency in single cell level. In cases with only occasional EBER-positive large or small lymphoid cells, LMP1 and EBNA2 were not detected. ZEBRA was negative in all the cases. These findings suggest that EBV may contribute to the pathogenesis of a small proportion of high-grade MALT lymphoma, where virtually all tumor cells harbored EBV and the oncogenic viral protein LMP1 was expressed. Moreover, latency III of EBV infection may exist in nonimmunocompromised patient. J. Med. Virol. 56:342–350, 1998 . © 1998 Wiley-Liss, Inc.     

胃肠MALT淋巴瘤中bcl-10 mRNA和蛋白的表达

目的　探讨bcl- 10基因在胃肠黏膜相关淋巴组织(MALT)淋巴瘤中的表达情况及意义。方法　采用免疫组化S P 法及原位杂交技术检测40例胃肠MALT淋巴瘤和14例正常淋巴结中bcl- 10基因的表达。结果　40例MALT淋巴瘤中有36 例(90.0%)表达bcl- 10蛋白,其中21例仅在胞质表达,15例在胞质胞核同时表达;39例(97.5%)表达bcl 10mRNA。bcl -10 蛋白与mRNA表达之间差异无统计学意义(P>0.05)。MALT淋巴瘤临床分期与bcl- 10蛋白核表达明显相关(P<0.01)。14 例淋巴结中,8例(57.1%)表达bcl -10蛋白。淋巴滤泡内生发中心B细胞呈高度表达,边缘区B细胞中等强度表达,套区细胞 微弱表达。结论　bcl -10的高度表达在MALT淋巴瘤发生发展可能起着重要作用。bcl -10蛋白核表达与进展期MALT淋巴瘤 相关。bcl -10蛋白在淋巴滤泡各区域的表达差异提示它对B细胞分化成熟有着重要意义。     

儿童淋巴瘤患者EBV-LMP1基因C末端30bp缺失突变检测

目的 研究儿童淋巴瘤来源的EBV-LMP1基因C末端30 bp缺失突变情况并分析其意义.方法 应用巢式聚合酶链反应技术(Nested-PCR)扩增免疫组化检测EBV-LMP1或原位杂交检测EBV.EBERS阳性的霍奇金淋巴瘤、非霍奇金淋巴瘤和淋巴结反应性增生病理标本中EBV-LMP1基因,并进行序列分析.结果 EBV-LMP1羧基端30 bp缺失的del-LMP1的检出率在霍奇金淋巴瘤、非霍奇金淋巴瘤和淋巴结反应性增生分别为11/25、3/8和5/15,三组间差异无统计学意义(P=0.793,X2=0.463).经序列分析发现,所扩增的EBV-LmP1基因型可分为三个亚型:B95.8、China1和China2.结论 EBV羧基端30 bp缺失的del-LMP1基因型广泛存在EBV阳性的儿童霍奇金淋巴瘤、非霍奇金淋巴瘤和淋巴结反应性增生病例中,与疾病本身没有关系.儿童来源的EBV-LMP1基因型主要可分为B95.8、China1和China2三个亚型.     

鼻咽癌高发区何杰金病EB病毒DNA及潜伏感染膜蛋白检测的意义

为检测鼻咽癌高发区何杰金病中爱泼斯坦-巴尔病毒（EBV）DNA及其表达产物──潜伏感染膜蛋白的存在及探讨其意义，采用热启动聚合酶链反应（PCR）及LSAB免疫组化法结合微波处理技术，检测了选自鼻咽癌高发区的40例何杰金病、20例淋巴结良性病变存档标本中的EBVDNA和潜伏感染膜蛋白（LMP1）。结果显示：65％的何杰金病中EBVDNA阳性，淋巴结良性病变中的阳性率也达50．0％（10例／20例），两者差异无显著性（P＜0．05）。LMP1只在何杰金病肿瘤细胞中表达，其检出率为52．5％（21例／40例）。20岁以下何杰金病中EBVDNA和LMP1的检出率分别为84．6％（11例／13例）和76．9％（10例／13例），皆明显高于20岁以上年龄组（分别为14例／25例，56．0％和10例／25例，40．0％）P＜0．05。本结果表明：鼻咽癌高发区半数以上何杰金病肿瘤细胞中有EBV潜伏感染，并可能在肿瘤的发生发展中起着一定的作用。提示青少年何杰金病和EBV潜伏感染并表达LMP1的关系更为密切。     

Cooperative interactions among p53, bcl-2 and Epstein-Barr virus latent membrane protein 1 in nasopharyngeal carcinoma cells

Interactions among p53, bcl-2 and Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) in nasopharyngeal carcinoma (NPC) cells were evaluated by gene cotransfections. The data showed that bcl-2 expression was not only able to prevent the growth suppression induced by wild-type p53 but was also paradoxically able to inhibit the growth enhancement induced by mutant p53. Latent membrane protein 1 was shown to be capable of overcoming the growth inhibition induced by wild-type p53 and the synergistic cooperation with bcl-2 to enhance cellular growth. Latent membrane protein 1 could also cooperate with mutant p53 to provide a growth advantage for NPC cells. Most NPC revealed detectable overexpression of p53, and the majority of those were a wild type possibly responding to EBV infection. The coexpression of bcl-2 and LMP1 was thought to inhibit the growth suppression induced by wild-type p53 in NPC. But there was no associated expression between LMP1 and bcl-2 because we demonstrated that transfected LMP1 failed to induce bcl-2 expression in NPC cells in contrast to the findings in B cells. It is theorized that the cooperative expression of bcl-2 and LMP1 exists in the majority of NPC, while a minority of NPC have cooperative expression of LMP1 and mutant p53. Each cooperative interaction could play an important role in the development and progression of NPC.     

Immunocytochemical analysis of lymph node aspirates in patients with human immunodeficiency virus infection.

Thirty four patients positive for human immunodeficiency virus (HIV) who had lymphadenopathy were investigated using fine needle aspiration. Cytological analysis included immunocytochemical investigation with the alkaline phosphatase-antialkaline phosphatase (APAAP) method. All patients had confirmation of cytological diagnosis by lymph node biopsy. Fifteen aspirates with follicular hyperplasia were evaluated. Eleven patients showed B cell predominance. The B cell population did not show light chain restriction. Ten patients with B cell non-Hodgkin's lymphoma (five with Burkitt's lymphoma and five with B cell immunoblastic lymphoma) were investigated. Nine out of 10 cases were monoclonal with respect to their light chain determinants; only one case with Burkitt's lymphoma with partial lymph node metastasis did not show light chain restriction. The cytological diagnosis included two mycobacterial infections and four cystic lesions. Histological investigation was necessary to diagnose the extent of lymph node disease caused by Kaposi's sarcoma. These findings indicate that the immunocytological investigation of lymph node aspirates is useful for evaluating lymphadenopathy in HIV positive patients.     

Association of Epstein-Barr virus infection with p53 protein accumulation but not bcl-2 protein in nasopharyngeal carcinoma

AIMS: The aim of this study was to investigate the association of Epstein-Barr virus (EBV) infection with status of p53 protein expression in nasopharyngeal carcinoma (NPC). The expression of EBV gene and gene product, p53 protein and bcl-2 protein in NPC was histopathologically studied. METHODS AND RESULTS: In-situ hybridization using oligonucleotide probe to EBV-encoded small RNAs (EBERs) and immunohistochemistry using monoclonal antibodies against EBV latent membrane protein 1 (LMP1), p53 protein and bcl-2 proteins were performed in 56 primary NPCs. EBERs were detected in 46 (82%) cases and LMP1 in 17 (30%) cases. While 30 of 32 (94%) cases in differentiated nonkeratinizing carcinoma (NKC, WHO type 2) and 16 of 17 (94%) cases in undifferentiated carcinoma (UC, WHO type 3) showed EBERs expression, neither five cases of keratinizing squamous cell carcinoma (KSCC, WHO type 1) nor two cases of adenocarcinoma showed EBERs. bcl-2 protein was detected in 50 (89%) cases, but its expression did not depend on expression of LMP1. p53 protein was detected in 31 (55%) cases, and there was a correlation between expression of EBERs and p53 protein (P < 0.05) but not between LMP1 and p53 protein. CONCLUSION: In this study, close association of NKC and UC but not KSCC with the latent infection with EBV was demonstrated. The induction of bcl-2 protein by LMP1, as shown in vitro, was not demonstrated. The association between overexpression of p53 protein and the presence of EBV suggests that some EBV-encoded protein, which may be different from LMP1, may play a role for nuclear accumulation of p53 protein.     

Presence of Epstein-Barr virus latency type III at the single cell level in post-transplantation lymphoproliferative disorders and AIDS related lymphomas.

AIMS: To investigate the expression pattern of Epstein-Barr virus (EBV) latent genes at the single cell level in post-transplantation lymphoproliferative disorders and acquired immunodefiency syndrome (AIDS) related lymphomas, in relation to cellular morphology. METHODS: Nine post-transplantation lymphoproliferative disorders and three AIDS related lymphomas were subjected to immunohistochemistry using monoclonal antibodies specific for EBV nuclear antigen 1 (EBNA1) (2H4), EBNA2 (PE2 and the new rat anti-EBNA2 monoclonal antibodies 1E6, R3, and 3E9), and LMP1 (CS1-4 and S12). Double staining was performed combining R3 or 3E9 with S12. RESULTS: R3 and 3E9 anti-EBNA2 monoclonal antibodies were more sensitive than PE2, enabling the detection of more EBNA2 positive lymphoma cells. Both in post-transplantation lymphoproliferative disorders and AIDS related lymphomas, different expression patterns were detected at the single cell level. Smaller neoplastic cells were positive for EBNA2 but negative for LMP1. Larger and more blastic neoplastic cells, sometimes resembling Reed-Sternberg cells, were LMP1 positive but EBNA2 negative (EBV latency type II). Morphologically intermediate neoplastic cells coexpressing EBNA2 and LMP1 (EBV latency type III), were detected using R3 and 3E9, and formed a considerable part of the neoplastic population in four of nine post-transplantation lymphoproliferative disorders and two of three AIDS related lymphomas. All samples contained a subpopulation of small tumour cells positive exclusively for Epstein-Barr early RNA and EBNA1. The relation between cellular morphology and EBV expression patterns in this study was less pronounced in AIDS related lymphomas than in post-transplantation lymphoproliferative disorders, because the AIDS related lymphomas were less polymorphic than the post-transplantation lymphoproliferative disorders. CONCLUSIONS: In post-transplantation lymphoproliferative disorders and AIDS related lymphomas, EBV latency type III can be detected by immunohistochemistry in a subpopulation of tumour cells using sensitive monoclonal antibodies R3 and 3E9. Our data suggest that EBV infected tumour cells in these lymphomas undergo gradual changes in the expression of EBV latent genes, and that these changes are associated with changes in cellular morphology.     

bcl-2 PROTEIN IS STRONGLY EXPRESSED IN POST-TRANSPLANT LYMPHOPROLIFERATIVE DISORDERS

The aim of this study was to examine a series of Epstein–Barr virus (EBV)-driven post-transplant lymphoproliferative disorders (PTLDs), in order to ascertain the level of bcl-2 immunostaining; to explore the relationship between bcl-2 and p53 protein expression; and to see if any correlation exists between bcl-2 and EBV-latent membrane protein 1 (LMP-1). Seventeen renal and 11 heart/heart–lung PTLD cases were stained with antibodies to EBV-LMP-1, bcl-2 and p53, using paraffin-embedded tissue. All cases of PTLD strongly co-expressed bcl-2 and EBV-LMP. Positive staining was present in small lymphoid and larger immunoblastic cells. These two antibodies showed parallel staining intensity. p53 expression was noted in 13 of 17 renal PTLDs, but in ten of the positive cases only 5–10 per cent of cells were stained. Seven of the 11 heart/heart–lung cases showed 50–60 per cent of cells to be p53-positive; in the remaining four cases, 10–20 per cent of cells were positive. bcl-2 protein, as detected by immunohistochemistry, is markedly overexpressed in all cases of PTLD. This study also demonstrates a strongly positive correlation between bcl-2 expression and EBV-LMP-1 detection in PTLDs. An inverse pattern of p53 and bcl-2 immunoexpression is noted in PTLDs with ‘high grade’ histology: these show marked expression of bcl-2, while p53 is downregulated. A Fisher's exact test yielded a P value of 0·12 when comparing p53-positive renal PTLDs with p53-positive heart/heart–lung PTLDs, indicating that any difference seen is not statistically significant. The postulated mechanism for the positive correlation between bcl-2 and EBV-LMP-1 is that EBV upregulates bcl-2, either directly or indirectly, thus promoting cell survival and ultimately successful viral replication.     

Correlation of the expression of Epstein-Barr virus latent membrane protein and in situ hybridization with biotinylated BamHI-W probes in Hodgkin''s disease.

The detection of Epstein-Barr virus (EBV) nucleic acids by in situ hybridization (ISH) with biotinylated BamHI-W probes was correlated with the expressions of EBV latent membrane protein (LMP) and EB nuclear antigen 2 (EBNA2), in 107 cases of Hodgkin's disease (HD) of different immunomorphologic subtypes. Epstein-Barr virus nucleic acids were present and restricted to the pathogenic cells in 4 of 40 (10%) cases of nodular sclerosis (NS) and 33 of 55 (60%) cases of mixed cellularity (MC), but were undetectable in other subtypes. Of the 37 cases positive for EBV nucleic acids, 35 (95%) showed the expression of LMP. Epstein-Barr virus nucleic acids and LMP were restricted to Reed-Sternberg cells and variants. Only 1 case (MC) showed LMP expression in the absence of EBV detection. The correlation was strengthened by the finding of LMP expression at first diagnosis in 6/7 EBV positive cases at relapse (14-126 months) (5/5 EBV negative cases at relapse were LMP negative at first diagnosis). EBNA2 was absent in all 13 (NS, 2; MC, 11) EBV+ and LMP+ cases tested. Both LMP and EBNA2 were expressed in control EBV-positive tissues and cell lines. EBV serology in MC HD was indicative of latent EBV infection, but neither serology nor clinical parameters correlated with the presence or the absence of EBV, over a short-term follow-up (median, 20 months). The findings, although not proving EBV as the etiologic agent of HD, suggest that: 1) LMP expression alone may be adequate for identifying EBV-associated HD, 2) the MC subtype has a stronger relation with EBV presence, and 3) the regulation of EBV genes in HD is different from other EBV-associated disorders. The clinical implications still remain to be discovered.     

Epstein–Barr virus in Reed–Sternberg G-like cells in non Hodgkin's lymphomas

In the course of our study on Hodgkin's disease (HD), ten cases of non-Hodgkin's lymphomas (NHL) containing Hodgkin and Reed-Sternberg-like (MRS) cells were encountered. Many of these cases had initially been diagnosed as HD, but on careful review of the histology, with the aid of immunophenotyping studies, they were reclassified as NHL. The presence of Epstein–Barr virus (EBV) in these HRS-like cells was investigated using a combination of EBER in situ hybridization (ISH) and immunostaining for the detection of EBV-encoded latent membrane protein (LMP). HRS-like cells in four cases (two lymphoplasmacytoid lymphomas, one Richter's transformation of lymphoplasmacytoid lymphoma, and one immunoblastic lymphoma of T-cell type) were found to be EBV-positive. In two of these cases, a second biopsy taken up to 10 years later also contained EBV in the HRS-like cells. In three of the four cases, HRS-like cells expressed the activation antigen CD30, but the expression of B- or T-cell antigens was variable. All cases of T-cell-rich B-cell lymphomas were negative for EBV. In conclusion, EBV may play a role in the development of HRS-like cells i some cases of NHL. The relationship of HRS-like cells to HRS cells of HD is discussed.     

Epstein-Barr virus infection and bcl-2 proto-oncogene expression. Separate events in the pathogenesis of Hodgkin's disease?

The present study was undertaken to investigate whether Epstein-Barr virus-(EBV) encoded latent membrane protein (LMP) induces the expression of BCL-2 in Hodgkin and Reed-Sternberg (HRS) cells of Hodgkin's disease (HD) and thereby provide a possible mechanism for the role of EBV in the pathogenesis of this disease. Fifty-three cases of HD were studied for the presence of EBV using EBV-encoded RNA in situ hybridization and LMP immunohistochemistry. Immunostaining for BCL-2 on paraffin material was performed using microwave treatment of tissue sections before the application of the primary monoclonal antibody. EBV was located in HRS cells in 16 cases (30%). All cases that were EBV-encoded RNA in situ hybridization positive, also expressed LMP. BCL-2 expression in HRS cells was detected in 16 cases (30%), but only two of these were also EBV-positive. In both of these cases, only occasional HRS cells expressed BCL-2, in contrast to LMP, which was detected in nearly all such cells. BCL-2 staining was predominantly cytoplasmic with some membrane pattern. These results demonstrate that BCL-2 expression can be detected in HRS cells in routinely processed HD tissue and that whereas EBV does not induce the expression of BCL-2 in HD, BCL-2 may have a role in the pathogenesis of EBV-negative cases of HD.