Epstein-Barr virus and carcinomas

The Correlation between Risk Factors and Epstein-Barr Virus Serum Antibody with Histopathological Typing of Nasopharyngeal Carcinoma

BACKGROUND: The risk-combination of genetic or familial history, environmental risk factors, and EBV infection might cause nasopharyngeal carcinogenesis. The serum antibody for EBV IgA, namely, EBNA1+VCA-p18 has a good sensitivity as an early diagnostic test for nasopharyngeal carcinoma (NPC). AIM: This study aims to determine the correlation between risk factors and histopathological typing of NPC and also the correlation between the IgA [EBNA-1 + VCA p-18] ELISA and histologic type. METHODS: A cross-sectional method was used on 108 NPC patients which filled a questionnaire through an in-depth interview on the family condition to cancer, habit/lifestyle, and environmental risks. A total of 47 subjects were willing to donate blood samples for IgA [EBNA1 + VCA p-18] ELISA. Furthermore, Kendall’s tau-b (τ) correlation test was performed on NPC keratin type (WHO-1) and non-keratin (WHO-2 and 3). RESULTS: The results showed that the family history of non-keratinized NPC was associated with NPC WHO-3 as demonstrated by τ = 0.473, as well as salt-eating with τ = 0.334, smoked/grilled fish/meat eating τ = 0.205, instant noodle-eating τ = 0.356, consuming canned/packaged canned foods τ = 0.240, and flavored food eating habits τ = 0.364, along with passive smoking τ = 0.377, and chronic nasopharyngeal infection τ = 0.530. The IgA titers, namely, [EBNA1 + VCA p-18] ELISA for non-keratin type NPC was greater than the keratin type; however, it was not related to WHO-3 NPC as indicated by τ = 0.376, and p = 0.011 put this underlying before however. CONCLUSIONS: The positivity of IgA [EBNA-1 + VCA p-18] ELISA does not correlate with the non-keratin type histologic NPC, family history, as well as salt-eating, instant noodle, and flavored food eating habits, along with passive smoking and nasopharyngeal infection.

The high frequency of EBV infection in pediatric Hodgkin lymphoma is related to the classical type in Bahia, Brazil

Pediatric Hodgkin lymphoma (HL) occurring in developing regions is different from HL in industrialized countries due to the higher frequency of association with Epstein-Barr virus (EBV) infection. This infection is related to classical HL (cHL) but is virtually absent in nodular lymphocyte predominant HL (nLPHL). We studied the phenotype and the expression of EBV gene products in 90 pediatric cases by immunohistochemistry and in situ hybridization. EBV-positive tumor cells were found exclusively in cHL. The infection occurred with high frequency in all cHL subtypes, but it predominated in the mixed cellularity and lymphocyte depletion subtypes. These results reinforce the hypothesis that EBV plays a major role in the etiology of pediatric cHL in developing areas. Curiously, the frequency of EBV infection in HL was identical to the previously described for Burkitt's lymphoma in the same pediatric population. As both lymphomas have a postulated precursor cell in the germinal center (GC), the pattern of latently EBV-infected GC cells previously described in Bahia may be related to the development of these lymphomas.

The aetiology of nasopharyngeal carcinoma

Nasopharyngeal carcinoma is a disease with a remarkable racial and geographical distribution. In most parts of the world it is a rare condition and in only a handful of places does this low risk profile alter. These include the Southern Chinese, Eskimos and other Arctic natives, inhabitants of South-East Asia and also the populations of North Africa and Kuwait.

Lack of Epstein-Barr virus infection in cervical carcinomas

CONTEXT

The Epstein-Barr virus (EBV) is a ubiquitous microorganism strongly associated with lymphoproliferative disorders and a large number of human neoplasms, mainly undifferentiated nasopharyngeal carcinoma and Burkitt lymphoma. The viral DNA has been detected in other tumors, such as carcinomas from tonsil, salivary glands, and thymus, and malignancies of the female genital tract. Some authors have proposed that EBV could play a role in the carcinogenesis of cervical tumors; however, other studies do not support this hypothesis.

OBJECTIVE

To assess whether EBV is associated with female genital tract neoplasms.

DESIGN

Sixty-five biopsy specimens (5 in situ carcinomas, 24 invasive squamous cell carcinomas, 6 lymphoepithelioma-like carcinomas, and 30 endocervical adenocarcinomas) were used to perform EBV detection through RNA in situ hybridization.

RESULTS

None of the cervical carcinoma cases studied was positive for EBV infection.

CONCLUSIONS

The results suggest that it is still premature to incriminate EBV in the carcinogenesis of cervical carcinoma.

Specific expression of Epstein-Barr virus in cutaneous squamous cell carcinomas from heart transplant recipients

BACKGROUND

We investigated a Swedish group of 114 immunosuppressed cardiac allograft patients for the occurrence of posttransplant cutaneous squamous cell carcinomas. A total of 15 tumors were detected in specimens from 5 patients.

METHODS

The tumors were analyzed for the presence of Epstein-Barr virus (EBV) genomes as well as EBV-specific gene expression by using three different techniques; the polymerase chain reaction (PCR), in situ hybridization, and immunohistochemistry. The material was also tested by PCR for high-risk human papilloma virus genome.

RESULTS

EBV DNA could be detected by PCR in 10 of the investigated tumors, 7 of which also expressed EBV latent membrane protein 1 and/or EBV-encoded RNAs. No EBV genomes or EBV gene products could be detected in normal skin/resection margins, available from three of the tumors investigated. All tumors were negative for high-risk human papilloma virus DNA analyzed by PCR.

CONCLUSIONS

In this study, we have found a high incidence of EBV-specific expression in posttransplant cutaneous squamous cell carcinomas. These results suggest that at least some of the skin cancers developing in immunocompromised heart transplant recipients are associated with EBV.

The physiologic reservoir of Epstein-Barr virus does not map to upper aerodigestive tissues

The human Epstein-Barr herpesvirus (EBV) has distinct oncogenic potential, but with over 90% of the adult world population infected, malignancy is a rare outcome of carrier status. However, EBV's association with over half of Hodgkin's and non-Hodgkin's lymphomas as well as several solid tumors, notably nasopharyngeal carcinoma, makes EBV-linked malignancies one of the largest single cancer entities. EBV is a B-lymphotropic virus, well controlled by surveillant T cells in immunocompetent hosts. To determine the presence and site of principal virus reservoirs is a likely prerequisite for understanding the etiology of EBV-associated tumors. Its near 100% association with nasopharyngeal carcinoma led to postulates that the upper aerodigestive tract tissue may be common sites of persistent latent or low-grade replicating infection. Using a protocol designed to avoid viral crosscontamination, the authors employed polymerase chain reaction to detect genomic EBV DNA sequences in 231 biopsies from different mucosal sites in the upper aerodigestive tract, as well as from salivary gland tissue and neck nodes in individuals not suspected to have EBV-related malignancy. Only two samples, one from oral cavity mucosa and one from parotid gland tissue, were positive for EBV. The observation that oropharyngeal tissue is not the principal EBV reservoir has mechanistic implications for the development of EBV-positive tumors in that locale.

Epstein-Barr virus and Hodgkin's disease

Seroepidemiological and molecular biological studies have established an association of Hodgkin's disease with Epstein-Barr virus. Recently, Epstein-Barr virus genomes and gene products have been detected in the neoplastic cells of approximately 50% of cases, most notably the latent membrane protein, which has transforming potential. However, Epstein-Barr virus was not restricted to neoplastic cells. In situ hybridization, employing probes for the small Epstein-Barr virus-encoded nuclear RNAs EBER1 and -2, helped to precisely characterize phenotype and distribution of all latently Epstein-Barr virus-infected cells, indicating the presence of usually small numbers of Epstein-Barr virus-infected, but latent membrane protein-negative, non-malignant B-cells of polyclonal origin in lymph nodes from Hodgkin's disease patients and normal controls. In contrast, the neoplastic cells and the Epstein-Barr virus genomes expressing latent membrane protein in these cells appear to be monoclonal in nature, which points to specific immunological deficiencies in Hodgkin's disease patients and suggests that Epstein-Barr virus may contribute to the etiology of a significant proportion of Hodgkin's disease cases.

Epstein-Barr virus and carcinomas: rare association of the virus with gastric adenocarcinomas

We have analysed 174 gastric carcinomas from the United Kingdom and from Japan for the presence of Epstein-Barr virus (EBV) using in situ hybridisation for the small EBV-encoded nuclear RNAs (EBERs). EBV was detected in the tumour cells in all of six undifferentiated gastric carcinomas with prominent lymphoid stroma (undifferentiated carcinomas of nasopharyngeal type, UCNT) but only in three of the remaining 168 typical gastric adenocarcinomas (1.8%). No differences were observed between the British and the Japanese cases. One case with an EBV-positive UCNT showed adjacent areas of EBV-negative typical adenocarcinoma. It is uncertain whether these patterns represent two independent carcinomas or whether they are the result of heterogeneous EBV infection in a single tumour. In the remaining EBV-positive carcinomas, viral transcripts were detected in virtually all tumour cells, indicating that EBV infection must have taken place early in the neoplastic process and suggesting that the virus is likely to be of pathogenetic significance for the virus-associated tumours. Immunohistology demonstrated absence of detectable levels of the EBV-encoded latent membrane protein, LMP1, and nuclear antigen, EBNA2. The BZLF1 protein which induces the switch from latent to lytic infection was demonstrated in a small proportion of the tumour cells in three cases. The close association of EBV with undifferentiated gastric carcinomas compared to the variable association with gastric adenocarcinomas suggests fundamentally different roles for the virus in the aetiology of these two malignancies.