Epstein-Barr virus: an aetiological factor in cutaneous lymphoproliferative disorders?

Species-specific transformation of T cells by HV(MNE)

HV(MNE) is an Epstein-Barr virus (EBV)-like lymphocryptovirus (LCV) originally isolated from a Macaca nemestrina with CD8(+) T cell mycosis fungoides/cutaneous T cell lymphoma (Blood 98 (2001), 2193). HV(MNE) transforms rabbit T cells in vitro and causes T cell lymphoma in New Zealand white rabbits. Here we demonstrate that HV(MNE) also immortalizes T cells from mustached tamarins but not those from owl monkeys, common marmosets, squirrel monkeys, black-capped capuchins, and humans. Cytogenetic and FACS analysis revealed the true origin and T cell lineage of the transformed tamarin T cell lines. Tamarin T cells contained HV(MNE) DNA sequence and displayed a decreased requirement for the IL-2 cytokine for growth. Thus, this EBV-like virus from M. nemestrina differs from the other EBV-like viruses found in nonhuman primates inasmuch as it appears to preferentially transform T cells.

HV(MNE), a novel lymphocryptovirus related to Epstein-Barr virus, induces lymphoma in New Zealand White rabbits

HV(MNE) is a novel Epstein-Barr (EBV)-like virus isolated from a Macaca nemestrina with CD8(+) T-cell mycosis fungoides-cutaneous T-cell lymphoma. Here it is demonstrated that intravenous inoculation of irradiated HV(MNE)-infected T cells or cell-free virus from the J94356(PBMC) cell line in New Zealand White rabbits results in seroconversion to the viral capsid antigen (VCA) of EBV; all animals that seroconverted to VCA developed malignant lymphoma within months of inoculation. In contrast, control rabbits, inoculated with heat-inactivated culture supernatants from the same cell line, failed to seroconvert to VCA and did not develop disease. Disseminated lymphoma cells of mixed origin were detected in most vital organs, including the spleen, liver, lungs, kidneys, and heart of the affected rabbits. Neoplastic infiltrates were also observed in lymph nodes, thymus, skin, and subcutaneous tissues. HV(MNE) DNA and EBV-like RNA expression was demonstrated in the lymphomatous organs and in 2 transformed T-cell lines, one established from the lymph node and the other from the blood of the 2 lymphomatous animals. Analysis of one of these T-cell lines demonstrated the persistence of HV(MNE) DNA, expression of an LMP1-like protein, and acquisition of interleukin-2 independence, and constitutive activation of the Jak/STAT pathway. Thus, HV(MNE) in rabbits provides a valuable animal model for human T-cell lymphoma whereby genetic determinants for T-cell transformation by this EBV-like animal virus can be studied.

Examination of mycosis fungoides for the presence of Epstein-Barr virus and human herpesvirus-6 by polymerase chain reaction

BACKGROUND

The aetiology of cutaneous T-cell lymphoma (CTCL) remains unknown despite numerous investigations. In recent years, retroviruses and human herpesviruses have been implicated to play a causal part in CTCL.

OBJECTIVE

The aim of this study was to elucidate the possible aetiopathogenetic role of human herpesviruses (HHV) in mycosis fungoides (MF).

METHODS

Polymerase chain reaction was used to study formalin-fixed, paraffin-embedded lesional skin biopsies from 92 subjects with MF to evidence possible presence of Epstein-Barr virus (EBV) and HHV-6.

RESULTS

Biopsy specimens from nine subjects (9.8%) evidenced EBV DNA, whereas all except one of the subjects (1.1%) lacked HHV-6 DNA.

CONCLUSIONS

Although these findings do not support a primary aetiological role for EBV and HHV-6 in classical CTCL, the possibility remains that both viruses, particularly EBV, may act as potential cofactors in the development of CTCL.

Primary cutaneous B-cell lymphoma: review and current concepts

PURPOSE

Primary cutaneous B-cell lymphoma (PCBCL) has only recently been recognized as a distinct clinical entity. With the advent of improved immunophenotyping and immunogenotyping, increasing numbers of PCBCL cases are being diagnosed. However, there is much confusion regarding the classification, treatment, and prognosis of these patients. The purpose of this article is to review and analyze the available data to provide the clinician with a concise summary of the diagnosis, prognosis, and treatment of PCBCL.

DESIGN

We conducted a thorough review of the medical literature on PCBCL, with a focus on classification, prognosis, and treatment trials.

RESULTS AND CONCLUSION

PCBCL is defined as a B-cell lymphoma originating in the skin. There is no evidence of extracutaneous disease at presentation and for 6 months after diagnosis, as assessed by adequate staging procedures. Currently, the European Organization for Research and Treatment of Cancer classification is the most concise disease classification scheme, dividing the subtypes of PCBCL by clinical behavior and histopathologic findings. Based on this classification, the most common subtype of PCBCL is follicular center cell lymphoma. PCBCL is generally an indolent form of lymphoma with a good prognosis. Although local cutaneous recurrences are observed in 25% to 68% of patients, dissemination to internal organs is rare. Five-year survival rates typically range from 89% to 96%. A specific subtype, large B-cell lymphoma of the leg, is noted to have a poorer prognosis, with a 5-year survival rate of 58%. Overly aggressive treatment of PCBCL has not been shown to improve survival or prevent relapse. The treatment of choice usually varies depending on the type of PCBCL, the body surface area, and the location of the involvement, as well as the age and general health condition of the patient. The majority of studies indicate that PCBCL is highly responsive to radiation therapy. Polychemotherapy should be reserved for involvement of noncontiguous anatomic sites or those with extracutaneous spread.

A Novel Epstein-Barr Virus-Like Virus, HVMNE, in aMacaca Nemestrina With Mycosis Fungoides

Epstein-Barr virus (EBV) infection of humans has been associated with the development of lymphoid malignancies mainly of B-cell lineage, although occasionally T-cell lymphomas have been reported. We describe here the characterization of a novel EBV-like virus (HVMNE) isolated from a simian T-cell lymphotropic virus type I/II (STLV-I/II) seronegative pigtailed macaque (Macaca nemestrina) with a cutaneous T-cell lymphoma. Immunohistochemistry studies on the skin lesions demonstrated that the infiltrating cells were of the CD3+/CD8+ phenotype. Two primary transformed CD8+ T-cell lines were obtained from cultures of peripheral blood mononuclear cells (PBMC) and skin, and, with time, both cell lines became interleukin-2–independent and acquired the constitutive activation of STAT proteins. Polymerase chain reaction analysis of the DNA from the cell lines and tissues from the lymphomatous animal demonstrated the presence of a 536-bp DNA fragment that was 90% identical to EBV polymerase gene sequences, whereas the same DNA was consistently negative for STLV-I/II sequences. Electron microscopy performed on both cell lines, after sodium butyrate treatment, showed the presence of a herpes-like virus that was designated HVMNE according to the existing nomenclature. In situ hybridization studies using EBV Epstein-Barr viral-encoded RNA probes showed viral RNA expression in both CD8+ T-cell lines as well as in the infiltrating CD8+ T cells of skin-tissue biopsies. Phylogenetic analysis of a 465-bp fragment from the polymerase gene of HVMNE placed this virus within theLymphocryptovirus genus and demonstrated that HVMNEis a distinct virus, clearly related to human EBV and other EBV-like herpesviruses found in nonhuman primates.

A Novel Epstein-Barr Virus-Like Virus, HVMNE, in aMacaca Nemestrina With Mycosis Fungoides

Epstein-Barr virus (EBV) infection of humans has been associated with the development of lymphoid malignancies mainly of B-cell lineage, although occasionally T-cell lymphomas have been reported. We describe here the characterization of a novel EBV-like virus (HVMNE) isolated from a simian T-cell lymphotropic virus type I/II (STLV-I/II) seronegative pigtailed macaque (Macaca nemestrina) with a cutaneous T-cell lymphoma. Immunohistochemistry studies on the skin lesions demonstrated that the infiltrating cells were of the CD3+/CD8+ phenotype. Two primary transformed CD8+ T-cell lines were obtained from cultures of peripheral blood mononuclear cells (PBMC) and skin, and, with time, both cell lines became interleukin-2–independent and acquired the constitutive activation of STAT proteins. Polymerase chain reaction analysis of the DNA from the cell lines and tissues from the lymphomatous animal demonstrated the presence of a 536-bp DNA fragment that was 90% identical to EBV polymerase gene sequences, whereas the same DNA was consistently negative for STLV-I/II sequences. Electron microscopy performed on both cell lines, after sodium butyrate treatment, showed the presence of a herpes-like virus that was designated HVMNE according to the existing nomenclature. In situ hybridization studies using EBV Epstein-Barr viral-encoded RNA probes showed viral RNA expression in both CD8+ T-cell lines as well as in the infiltrating CD8+ T cells of skin-tissue biopsies. Phylogenetic analysis of a 465-bp fragment from the polymerase gene of HVMNE placed this virus within theLymphocryptovirus genus and demonstrated that HVMNEis a distinct virus, clearly related to human EBV and other EBV-like herpesviruses found in nonhuman primates.

Cutaneous CD30 positive large T cell lymphoma of the upper lip: a rare presentation

Primary cutaneous CD30 positive large T cell lymphomas (PCLCL) are very rare in the head and neck region. We report a case which presented on the right upper lip in a 48-year-old male. This was an isolated cutaneous lesion and in these circumstances this otherwise aggressive lymphoma has an excellent prognosis.

Absence of Epstein-Barr viral encoded RNA (EBER) in primary cutaneous t-cell lymphoma

Epstein-Barr virus (EBV) has been associated with various extracutaneous lymphoproliferative diseases and it has been suggested that EBV may have a similar aetiological role in cutaneous T-cell lymphoma. In this study, in situ hybridization was used to investigate the presence of EBV encoded RNAs (EBER-1 and EBER-2) in 37 biopsies from 28 cases of primary cutaneous T-cell lymphoma originating from the U.K. The results showed that EBV had no demonstrable pathogenic role in the lymphomas studied, as EBER was not detected in any case.

Epstein-Barr virus in cutaneous lymphomatoid granulomatosis

Epstein-Barr virus (EBV) has been associated with various extra-cutaneous lymphoproliferative diseases and it has been suggested that EBV may have a similar aetiological role in the skin. In this study, 10 biopsies from 7 cases of primary cutaneous lymphomatoid granulomatosis have been analyzed, using in situ hybridisation, for the presence of EBV encoded RNAs (EBER-1 and EBER-2). Only one case showed positive staining with the EBER probes and it is concluded that, in the skin, the relationship between EBV and lymphomatoid granulomatosis is variable. The role of EBV as an etiological agent in primary cutaneous lymphomatoid granulomatosis appears less important than in primary respiratory disease.

Persistence of human T cell lymphotropic virus type 1 (HTLV-1) sequences in peripheral blood mononuclear cells from patients with mycosis fungoides

Mycosis fungoides (MF) is a rare form of cutaneous T cell lymphoma suspected of having a viral etiology. As in adult T cell leukemia, the virus involved may be human T lymphotropic virus type 1 (HTLV-1). We cultured the peripheral blood mononuclear cells (PBMC) of 29 patients with MF HTLV-1 seronegative by enzyme-linked immunosorbent assay and Western blot. The presence of reverse transcriptase (RT) and p24 antigen was investigated in the concentrate supernatant of the culture. The DNA of all studied patients was submitted to polymerase chain reaction and Southern blot analysis using primers and probes recognizing the tax region of HTLV-1/2 and the pol region of HTLV-1. 10 of 29 patients were found positive to HTLV-1, whereas they were always negative to RT and p24. The same results were confirmed in double blind after 6 mo. Our findings suggest HTLV-1 may be involved in the etiology of MF, at least in certain cases.

Mycosis fungoides: expression of C-myc p62 p53, bcl-2 and PCNA proteins and absence of association with Epstein-Barr virus

The expression of C-myc p62, bcl-2, p53, PCNA and EBV-encoded LMP-1 proteins was studied by immunohistochemistry on paraffin-embedded skin specimens from 14 patients with early stage (premycotic erythema and second stage plaques) mycosis fungoides (MF), 21 patients with advanced stage MF (third stage plaques and tumors), 3 patients with Sezary's syndrome (SS) and 3 patients with pleomorphic medium and large cell cutaneous T-cell lymphomas (PML-CTCL). All 41 cases were also screened for the presence of EBV by using RNA in situ hybridization with EBER 1/2 oligonucleotides. Increased expression of C-myc p62, p53 and PCNA proteins was found in PML-CTCL and advanced stages of MF as compared to early stages of MF. These results suggest a relationship between levels of C-myc p62, p53 and PCNA proteins and aggressiveness of the cutaneous T-cell lymphomas. Furthermore, C-myc p62 and bcl-2 proteins were found to be frequently coexpressed in the present series. In view of the background information from in vitro findings and animal models that cooperation of C-myc and bcl-2 is important for lymphomagenesis, our results suggest that coexpression of these oncogenes may be implicated in the pathogenesis and/or the progression of cutaneous T-cell lymphomas. Neither LMP-1 expression nor EBV EBER l/2 transcripts were detected in our series suggesting that EBV is not involved in the pathogenesis of cutaneous T-cell lymphomas.

Cutaneous manifestations of Epstein-Barr virus-associated T-cell lymphoma

BACKGROUND

In addition to human T-lymphotropic virus (HTLV-I), the Epstein-Barr virus (EBV) has recently been demonstrated to be associated with cutaneous T-cell lymphoma (CTCL).

OBJECTIVE

Our purpose was to investigate characteristic clinicopathologic features of the cutaneous lesions of EBV-associated T-cell malignancies.

METHODS

Clinical records, laboratory data, and histopathologic sections were reviewed. Freshly frozen tumor tissues were immunophenotyped. Southern blot and in situ hybridization studies were performed to detect the EBV genomes.

RESULTS

Ten of 35 CTCL biopsy specimens collected between 1985 and 1992 were found to be EBV-associated. Clonotypic proliferation of EBV genomes was demonstrated in each case, and the atypical T lymphoid cells contained EBV genomes. The cutaneous eruptions of these patients included multiple violaceous papules or nodules, chronic ulcers, and tumors on the trunk or extremities. Three distinct clinicopathologic subgroups could be recognized. The most consistent was the angiocentric T-cell lymphoma or lymphomatoid granulomatosis (type III CTCL) (four cases), presenting with chronic ulcers or violaceous papules. The second group was the T large-cell lymphoma (type II CTCL), Ki-1 antigen (CD30) (positive or negative) (four cases). Three patients with Ki-1- lymphoma had fulminant disease, whereas the remaining Ki-1+ case had a benign course. The third group was the secondary type CTCL (type V CTCL) (two cases), representing systemic EBV-associated T-cell lymphoma. The prognosis was grave. The common features of these EBV-associated CTCLs are resistance to conventional chemotherapy, poor prognosis, and the terminal manifestation of a hemophagocytic syndrome. No EBV genome could be detected in 12 cases of classic CTCL/mycosis fungoides (type I CTCL), or in three cases of HTLV-I-associated adult T-cell lymphoma (type IV CTCL).

CONCLUSION

Three distinct clinicopathologic subtypes of EBV-associated CTCL were recognized, including one additional type of virus-associated CTCL.

Posttransplant cutaneous lymphoma

BACKGROUND

Posttransplant lymphoma is closely associated with Epstein-Barr virus (EBV) infection and appears to have a predilection for extranodal sites. We describe four cases of primary cutaneous posttransplant lymphoma.

OBJECTIVE

Our aim was to determine cell lineage and any possible association with EBV in each case of cutaneous lymphoma.

METHODS

Tumor tissue was examined by light microscopy, immunohistochemistry, nonisotopic in situ hybridization and polymerase chain reaction.

RESULTS

The data were consistent with a diagnosis of EBV-associated cutaneous B-cell lymphoma in three cases and cutaneous T-cell lymphoma not associated with EBV in one case. No patient with B-cell lymphoma had extracutaneous involvement during a mean follow-up of 3.9 years. The patient with cutaneous T-cell lymphoma died of cerebral involvement 9 months after initial presentation.

CONCLUSION

These data suggest a possible role for EBV infection in the origin of cutaneous B-cell lymphoma in immunosuppressed patients.

Examination of cutaneous T-cell lymphoma for human herpesviruses by using the polymerase chain reaction

The etiology of cutaneous T-cell lymphoma remains unknown, although an association with viral infection, in particular certain retroviruses and human herpesviruses, has been suggested. The purpose of this study was to examine skin biopsies of cutaneous T-cell lymphoma for the presence of Epstein-Barr virus, herpes simplex virus type 1 and type 2, and human herpesvirus-6 by using the polymerase chain reaction. Lesional skin biopsies from 30 patients with cutaneous T-cell lymphoma were studied. Control specimens included biopsies from 9 patients with lymphomatoid papulosis and 10 patients with pityriasis lichenoides et varioliformis acuta. DNA extracted from each specimen, as well as from a known positive control for each virus, was examined by using the polymerase chain reaction with viral-specific primers. Each DNA specimen was also amplified with control primers for human beta globin. The specificity of the amplified products was confirmed by Southern analysis. Neither Epstein-Barr virus nor herpes simplex virus was detected in any of the patient specimens examined. Human herpesvirus-6 was detected in one specimen of cutaneous T-cell lymphoma and one specimen of lymphomatoid papulosis. These results do not support a role for any of these herpesviruses in the pathogenesis of cutaneous T-cell lymphoma.

Absence of Epstein-Barr viral RNA in lymphomatoid papulosis

Epstein-Barr virus (EBV) recently has been implicated in the pathogenesis of Hodgkin's disease (HD). Lymphomatoid papulosis (LyP) is a premalignant cutaneous lymphoproliferative disorder which shares several characteristics with HD. The hypothesis has been made that EBV may be associated with the pathogenesis of LyP. We therefore examined 17 skin biopsy specimens and two lymph nodes from nine patients with LyP for EBV RNA using the highly sensitive and specific EBER method. In all specimens, the large atypical cells were negative for EBV while poly T studies confirmed the presence of adequate RNA for detection of EBER. The negative EBER results were confirmed in seven LyP patients whose biopsies were also stained for latent membrane protein (LMP-1). Interestingly, one patient with clonally related LyP and HD had no EBV RNA detected in any specimen. We conclude that EBV is unlikely to be an important aetiological agent in LyP. If confirmed in other patients, HD associated with LyP may have a different aetiology from HD arising de novo.

Diagnostic difficulties in 'non-mycotic' cutaneous lymphoproliferative diseases

The diagnosis of cutaneous lymphoproliferative diseases is an area of bewildering complexity to many histopathologists. This article concentrates on 'non-mycotic' cutaneous diseases. The 'current state of the diagnostic art' is critically assessed. Cutaneous 'pseudolymphoma' is relegated to the position of an aid-memoire and is not a diagnosis. Inadequacies in the classification of cutaneous lymphoma are discussed and the non-specificity of many histopathological features is highlighted. The status of specific entities is analysed and the contribution of modern investigative techniques in diagnosis is evaluated. This includes cutaneous T-cell lymphomas with a detailed consideration of large cell lymphoma heterogeneity. Cutaneous B-cell diseases are shown to be an unresolved diagnostic maze and the necessity for new clearly defined diagnostic criteria is emphasized. Evidence is presented to show that many cutaneous lymphoproliferative diseases lie on continuous spectra that, initially, are probably antigenically driven, and that a diagnosis is best achieved by a multifaceted approach. This is exemplified by cutaneous diseases that have origins from both B- (cutaneous lymphoid hyperplasia/lymphoma) and T-cells (lymphomatoid papulosis, lymphomatoid granulomatosis and mycosis fungoides). The future diagnostic role of the polymerase chain reaction and cytogenetic analysis is discussed. Intriguingly, recent molecular evidence has shown that lymphomatoid papulosis, cutaneous T-cell lymphoma, CD30 positive large cell lymphoma and Hodgkin's disease can originate from a single T-cell clone and display an identical chromosomal translocation and T-cell receptor rearrangement. Careful clinico-pathological correlation combined with prolonged patient follow-up remains the gold standard for diagnosis.