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

Detection of methylation status of Epstein-Barr virus DNA C promoter in the diagnosis of nasopharyngeal carcinoma

The detection of Epstein-Barr virus (EBV) DNA load in nasopharyngeal (NP) brushing samples for diagnosis of nasopharyngeal carcinoma (NPC) has attracted great attention. Further improvements that eliminate the need for clinical settings will greatly extend its application. A total of 250 participants were recruited to obtain NP brushing samples. Brush sampling both with and without the guide of endoscopy was conducted in 38 NPC patients. EBV DNA load, EBV RNA transcript and EBV DNA C promoter methylation status were, respectively, evaluated. Typical latency II transcripts were observed in brushing samples from NPC patients but not controls. Unlike in tissues, multiple lytic gene transcripts were observed not only in NPC patients but also in controls. Apart from EBV RNA transcript, samples from NPC patients also showed higher levels of EBV DNA load and C promoter methylation degree than their controls. Qualitative analysis further showed that EBV DNA C promoter was methylated in all NPC patients but in only 18.4% of the control group. Combined analysis of EBV DNA methylated degree and EBV DNA load increased the sensitivity to 100% in the detection of NPC. Using qualitative methylated type as the criteria, up to 89.5% of samples collected via blind brushing showed consistent results with samples collected via endoscopy-guided brushing from NPC patients. Detection of the methylation status of EBV DNA C promoter in NP brushing samples shows great potential in diagnosing NPC and may provide an appealing alternative for the non-invasive detection and screening of NPC without the need for clinical settings.

Epstein-Barr virus mir-bart1-5p detection via nasopharyngeal brush sampling is effective for diagnosing nasopharyngeal carcinoma

Epstein-Barr virus (EBV)-encoded microRNAs (miRNAs) are highly expressed in nasopharyngeal carcinoma (NPC) cases in high-risk areas, and may be involved in tumorigenesis. Using quantitative RT-PCR, we detected four EBV-encoded BamHI A rightward transcript (BART) miRNAs (mir-bart1-5p, mir-bart5, mir-bart6-5p and mir-bart17-5p) exclusively in 53 NPC biopsies as compared to 69 controls. In a larger patient group, that included 215 NPC cases and 209 controls, significantly higher levels of all four EBV miRNAs were detected in tumor cells harvested directly from the nasopharynx using a less invasive nasopharyngeal (NP) brush than in the controls (p < 0.001). One EBV miRNA, mir-bart1-5p, holds particular promise for use as a diagnostic indicator of NPC (with 93.5% sensitivity and 100% specificity), and its relative expression level was reflective of disease progression. Detection of this miRNA was effective for diagnosing early-stage NPC, even in cases that were falsely diagnosed as negative based on histopathological analysis, plasma EBV DNA load, and VCA-IgA and EA-IgA titers. EBV-encoded mir-bart1-5p detection via NP brush sampling could act as an efficient and less invasive method assisting clinical diagnosis of NPC.

Molecular diagnosis of nasopharyngeal carcinoma using detection of Epstein-Barr virus latent membrane protein-1 gene in cervical metastatic lymph nodes

BACKGROUND

Cervical lymphadenopathy could be a manifestation of occult nasopharyngeal carcinoma (NPC). Epstein-Barr virus (EBV) is frequently detected in NPC, and its malignant transformation is associated through the action of the oncoprotein latent membrane protein-1 (LMP-1).

PURPOSE

The aim of this study was to investigate whether a primary nasopharyngeal origin could be localized by detection of EBV LMP-1 gene in cervical metastatic lymph nodes.

MATERIALS AND METHODS

In this prospective study, 32 paraffin-embedded tissues of various head and neck carcinomas and 20 normal tonsil specimens were examined for the presence of LMP-1 gene, using polymerase chain reaction.

RESULTS

Ten of 12 nasopharyngeal biopsies and 8 of 10 metastatic lymph nodes of the same NPC were positive for LMP-1 gene. The LMP-1 gene was detected in metastatic lymph nodes of NPC, with a sensitivity of 80%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 91%. On the contrary, the LMP-1 gene was not detected in any of the samples of other head and neck carcinomas and their metastatic nodes as well as in tonsillar specimens. There was a significant association between the presence of LMP-1 gene and tumor location in the nasopharynx (P < .0001).

CONCLUSION

The presence of LMP-1 gene in metastatic cervical lymph nodes is significantly associated with nasopharyngeal origin of the carcinoma. Meanwhile, EBV has no role in the tumorigenesis of carcinomas arising from other head and neck regions.

Periodontitis lesions are a source of salivary cytomegalovirus and Epstein-Barr virus

AIM

Several herpesvirus species can be detected in periodontal pockets and saliva. This study compared human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) DNA copy counts in periodontitis sites and in whole saliva, and evaluated the potential of periodontal therapy to reduce the salivary level of the two viruses.

MATERIAL AND METHODS

A total of 20 systemically healthy periodontitis patients, 21-56 years of age, participated in the study. All 20 patients were examined at baseline, and seven patients also at 3 months after periodontal therapy. Treatment included oral hygiene instruction, scaling and root planing, and surgery. Clinical parameters were evaluated using established methods. In each patient, virological samples were collected from one periodontal pocket of 6-10 mm probing depth, from the adjacent inflamed periodontal pocket wall, and from unstimulated whole saliva. Relationships between subgingival, gingival tissue and salivary herpesvirus counts were evaluated using Spearman's and Kendall's rank correlation coefficient tests. The 5'-nuclease (TaqMan) real-time polymerase chain reaction (PCR) assay was employed to quantify genomic copies of periodontal HCMV and EBV.

RESULTS

At baseline, the 20 periodontitis patients showed significant positive correlations between gingival tissue and salivary counts of HCMV DNA (p=0.003) and EBV DNA (p=0.045). Periodontal pocket depth was positively correlated with salivary EBV DNA counts (p=0.002). Periodontal therapy reduced average full-mouth periodontal pocket depth from 4.6 mm to 1.4 mm, plaque index from 2.1 to 0.9, and gingival index from 2.1 to 0.4. Following treatment, HCMV DNA counts decreased 37.5 fold in subgingival sites and 64.6 fold in saliva, and EBV DNA counts decreased 5.7 fold in subgingival sites and 12.9 fold in saliva.

CONCLUSIONS

The present study provides compelling evidence of a periodontitis source for salivary HCMV and EBV. The potential of periodontal therapy to decrease herpesvirus salivary counts may help diminish herpesvirus transmission from person to person and herpesvirus-related diseases in exposed individuals. Further research is warranted to determine the relationship between periodontal herpesvirus counts and the risk of viral transmission to close acquaintances.

Study of the viral infections and cytokines associated with recurrent aphthous ulceration

Mouth ulcers are one of the most common oral complaints. However, the association between oral ulceration and viruses and cytokines is uncertain. We detected the presence of human papilloma virus (HPV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV)-1, HSV-2 and human herpesvirus (HHV)-8 DNA in oral tissues by polymerase chain reaction (PCR) and Southern hybridization techniques, and quantified the serum levels of cytokines including interleukin (IL)-2, IL-4, granulocyte-macrophage colony-stimulating factor (GM-CSF), soluble Fas (sFas) and the Fas ligand (FasL) by enzyme-linked immunosorbent assay (ELISA) for 67 recurrent aphthous ulcer (RAU) patients and 72 normal individuals. Seven patient specimens were excluded from the study due to the negative PCR results for the beta-globin used as the internal control. Among the 32 (53.3%) virus-positive results from 60 patients' samples, 8 (13.3%) HPV, 4 (6.7%) HSV-1, 11 (18.3%) CMV, 9 (15.0%) EBV, and 16 (26.7%) HHV-8 samples proved to be positive. No HSV-2-positive samples were found. The percentage of single-virus infection (56.3%) was significantly greater than that of double-virus co-infection (31.3%) and the percentage of double-virus co-infection was significantly greater than the percentage of triple-virus co-infection (12.5%) (P < 0.05). In the 72 normal oral-tissue specimens, no viral DNA was detected. The mean serum cytokine level for patients was significantly (P < 0.05) greater than for controls for most of the separate age groups. The mean serum cytokine concentrations for the patient group demonstrated a diffuse pattern covering a wide range of serum concentrations, a very different result from the compact serum concentration pattern and lower mean serum cytokine concentrations revealed by the normal group. Overall association between viruses and recurrent aphthous ulceration is HHV-8 > CMV > EBV > HPV > HSV-1, regarding the frequency of prevalence (P < 0.05).

Molecular diagnosis of nasopharyngeal carcinoma: detecting LMP-1 and EBNA by nasopharyngeal swab

OBJECTIVES

The aim of this study was to investigate the feasibility of molecular diagnosis of nasopharyngeal carcinoma (NPC) by combining nasopharyngeal swab and polymerase chain reaction (PCR) to detect Epstein-Barr virus (EBV) derived latent membrane protein-1 gene (LMP-1) and Epstein-Barr nuclear antigen gene (EBNA).

METHODS

437 adults underwent nasopharyngoscopy, possible biopsy, and nasopharyngeal swab to obtain nasopharyngeal cells for the detection of LMP-1 and EBNA by PCR.

RESULTS

By detecting LMP-1 and EBNA in the nasopharyngeal swabs, NPC could be diagnosed with a false-positive rate of 1.7% (6/354), a false-negative rate of 8.6% (6/70), a sensitivity of 91.4% (64/70), a specificity of 98.3% (348/354), positive predictive value of 91.4% (64/70), and negative predictive value of 98.3% (348/354).

CONCLUSION

Detecting EBV genomic LMP-1 and EBNA by nasopharyngeal swab verifies NPC with a sensitivity of 91.4% and specificity of 98.3%. The nasopharyngeal swab coupled with PCR based EBV LMP-1 and EBNA detection could serve as a good supplement to pathological diagnosis of NPC.

Role of cytomegalovirus, Epstein-Barr virus, and human herpes virus-8 in benign lymphoepithelial cysts of the parotid gland

OBJECTIVE

To provide background and evaluate the role of herpesviruses in benign lymphoepithelial cysts (BLC) of the parotid gland.

STUDY DESIGN

Case series derived from review of pathology specimens.

METHODS

Radiolabeled polymerase chain reaction (PCR) analysis was used to detect for the presence of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpes virus 8 (HHV-8) DNA sequences in 14 paraffin embedded specimens and 1 freshly aspirated BLC specimen. Thirteen normal parotid tissue specimens obtained from paraffin embedded blocks were used as a control group.

RESULTS

CMV was detected with nearly equal frequency between the two groups (23% of normal vs. 20% in BLC). HHV-8 was found in 13% of the BLC group and in none of the normal group (P =.4841). There was significant difference in EBV detection between the normal (0%) and the BLC (33%) groups (P =.0437).

CONCLUSION

CMV and HHV-8 does not appear to be associated with BLCs. Although EBV is found more frequently in BLC than in normal parotid controls, further studies are needed to elucidate the role of this virus in BLC pathogenesis.

Serum EBV DNA as a Biomarker in Primary Nasopharyngeal Carcinoma of Indian Origin

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a unique tumor due to its etiology and endemic distribution. Ethnic and regional factors are found to strongly influence the risk of disease; however, there have been no well-conducted studies on Indian patients. The present study assesses the relationship between Epstein-Barr Virus (EBV) and sporadic Indian NPC and the role of serum EBV DNA in NPC detection.

METHODS

Primers directed against non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene were used to detect the presence of EBV DNA from fresh tissue and serum in NPC, using PCR.

RESULTS

EBV DNA was detected in 69% of the biopsies and 58% of the serum of the NPC patients. With respect to histology, WHO Type III NPC, WHO Type II tumors and WHO I tumors showed 100%, 72.2% and 33% EBV positivity, respectively. EBV positivity was also observed in 23% (6/26) of benign samples. All biopsies of patients with positive serum samples were positive for EBV DNA.

CONCLUSION

EBV infection was found in sporadic NPC of South Indian origin, which confirms the etiological role of EBV in NPC. Detection of EBNA-1 in the serum and corresponding tissues of NPC patients suggests that the serum EBV DNA originates from NPC and also indicates the benefit of circulating viral DNA as an early marker in the diagnosis of NPC. Serum DNA-PCR methods can be extrapolated to follow-up studies involving tumor regression or to assess the response to various therapies.

Detection of Epstein-Barr virus-derived latent membrane protein-1 gene in various head and neck cancers: is it specific for nasopharyngeal carcinoma?

OBJECTIVE

The object of the study was to determine the incidence of the presence of Epstein-Barr virus-derived latent membrane protein-1 (LMP-1) gene in various head and neck cancers by polymerase chain reaction method.

STUDY DESIGN

Prospective study.

METHODS

During a 5-year period, polymerase chain reaction was used to investigate the presence of LMP-1 gene in various head and neck cancers from different locations and histopathological types, noncancerous nasopharyngeal biopsy samples, and tonsillectomy specimens from patients with chronic hypertrophic tonsillitis.

RESULTS

Of 202 patients enrolled in the study, 53 were diagnosed by pathological study with oropharyngeal carcinoma, 45 with nasopharyngeal carcinoma, 26 with oral cavity carcinoma, 26 with laryngohypopharyngeal carcinoma, 31 with nasopharyngeal lymphoid hyperplasia, and 21 with tonsils with lymphoid hyperplasia. After the application of polymerase chain reaction, the LMP-1 gene was not detected in any sample from oral cavity carcinoma, laryngohypopharyngeal carcinoma, or nasopharyngeal lymphoid hyperplasia or from tonsillectomy specimens but was detected in only one case of tonsillar carcinoma. On the contrary, the LMP-1 gene was detected in 43 (95.6%) of 45 samples from patients with nasopharyngeal carcinoma. The statistical analysis shows a significant association (P <.001) between the presence of LMP-1 gene and tumor localization in the nasopharynx.

CONCLUSIONS

The study shows that the presence of LMP-1 gene detected by polymerase chain reaction in the tumor cell is only significantly associated with tumor located in the nasopharynx, implying that Epstein-Barr virus plays a trifling role in the tumorigenesis of carcinomas arising from other head and neck locations. The polymerase chain reaction method that was used is a potential tool for screening nasopharyngeal carcinoma.

Role of Epstein-Barr virus and cytomegalovirus in the etiology of benign parotid tumors

BACKGROUND

Pleomorphic adenomas and Warthin's tumors are the two most common benign parotid tumors. Previous studies investigating the role of viruses in tumorigenesis of these neoplasms have been conflicting. The aim of this study was to determine whether Epstein-Barr virus (EBV) or cytomegalovirus (CMV) might play a role in the pathogenesis of pleomorphic adenomas and Warthin's tumors.

METHODS

Paraffin-embedded surgical specimens of 24 pleomorphic adenomas, 10 Warthin's tumors, and 13 normal parotid tissues were obtained from the University of California-San Francisco Pathology Department. Genomic DNA was extracted from the specimens, and primers for connexin 26, a gap junction protein, were used to confirm the integrity of this DNA. The presence or absence of EBV and CMV DNA within the samples was determined with PCR-based assays, in which radiolabeled primers were used for maximal sensitivity of detection.

RESULTS

PCR analysis of serially diluted control DNA revealed that using radiolabeled primers, five copies of viral DNA could be detected. By use of this method, we showed that none of the 24 pleomorphic adenomas, 10 Warthin's tumors, or 13 normal parotid samples contained EBV DNA or CMV DNA.

CONCLUSIONS

These results do not support CMV or EBV as etiologic factors in pleomorphic adenomas or Warthin's tumors. In addition, normal parotid seems not to harbor either of these viruses. Future studies with larger numbers of specimens are needed to confirm these findings.

Epstein-Barr virus infection in the pathogenesis of nasopharyngeal carcinoma

The association of nasopharyngeal carcinoma (NPC) with the Epstein-Barr virus (EBV) was firmly established as early as 1973. Nevertheless, the role for the virus in the pathogenesis of NPC is still controversial. In this article, the evidence implicating EBV in the development of NPC is reviewed, focusing on the cellular site of EBV persistence, the association of the virus with different NPC histotypes, the tumour cell phenotype in the context of viral latent gene expression, and the possible role of the lymphoid stroma.

Nasopharyngeal brush biopsies and detection of nasopharyngeal cancer in a high-risk population

BACKGROUND

Nasopharyngeal carcinoma (NPC) is an important tumor in many countries. Ethnic and regional factors strongly influence disease risk. NPC is usually diagnosed late in disease development, and 10-year survival rates are as low as 10%. Epstein-Barr virus (EBV), a possibly causative agent, is present in all cells of essentially all undifferentiated NPCs. We wished to determine the following: 1) whether an ambulatory nasopharyngeal brush biopsy could provide sufficient tumor cell DNA for the detection of EBV and 2) whether the detection of EBV in this locale reflects the presence of tumor cells or simply EBV carrier status.

METHODS

We collected nasopharyngeal tissue via ambulatory brush biopsies from 21 patients with newly diagnosed NPC and from 157 subjects with other otolaryngologic complaints. The majority of study subjects were from high-risk populations. Sample DNA was analyzed for the presence of EBV genomic sequences by use of the polymerase chain reaction (PCR).

RESULTS

Ninety-six percent of samples yielded sufficient DNA for PCR amplification. Nineteen of 21 patients with NPC brushed positive for EBV DNA, while all but two (1.3%) of 149 informative control subjects were negative for EBV (two-sided P<.0001). One of the EBV-positive control subjects had an EBV-positive inverted sinonasal papilloma; the other EBV-positive control subject exhibited no overt clinical disease.

CONCLUSION

Demonstration of EBV DNA in nasopharyngeal brush biopsy specimens detects NPC with a sensitivity of at least 90% (95% confidence interval = 89.63%-91.32%) and a specificity of approximately 99% (95% confidence interval = 98.64%-98.68%). This technique merits further testing as a possible ambulatory screening strategy in high-risk populations.