Analyses of Epstein-Barr virus latent membrane protein-1 in Malaysian nasopharyngeal carcinoma: High prevalence of 30-bp deletion, Xho1 polymorphism and evidence of dual infections

• Published in: Journal of medical virology Vol. 69; no. 2; pp. 251 - 257
• Main Authors: Tan, Eng-Lai, Peh, Suat-Cheng, Sam, Choon-Kook
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc., A Wiley Company 01-02-2003; Wiley-Liss
• Subjects: 30-bp deletion; 33-bp internal repeats; Biological and medical sciences; Carcinoma - virology; Cell Line; Deoxyribonucleases, Type II Site-Specific - genetics; Deoxyribonucleases, Type II Site-Specific - metabolism; DNA, Viral - analysis; EBV; Epstein-Barr Virus Infections - epidemiology; Epstein-Barr Virus Infections - virology; Exons - genetics; F-variant; Gene Deletion; Herpesvirus 4, Human - classification; Herpesvirus 4, Human - genetics; Herpesvirus 4, Human - isolation & purification; Herpesvirus 4, Human - metabolism; Human parasitic diseases due to arthropods; Humans; Infectious diseases; LMP-1; Malaysia - epidemiology; Medical sciences; nasopharyngeal carcinoma; Nasopharyngeal Neoplasms - epidemiology; Nasopharyngeal Neoplasms - virology; Parasitic diseases; Pharynx - virology; Polymerase Chain Reaction; Polymorphism, Genetic; Specimen Handling - methods; Viral Matrix Proteins - genetics; Viral Matrix Proteins - metabolism; Xho1 polymorphism; Asia; Malaysia; Gammaherpesvirinae; Human; Carcinoma; Prevalence; Repeated sequence; Herpesviridae; Nasopharynx; Epstein Barr virus; Malignant tumor; Epidemiology; Infection; Virus; Viral disease; Deletion; Molecular epidemiology; ENT disease; Pharynx disease; Mutation; Polymorphism
• ISSN: 0146-6615; 1096-9071
• DOI: 10.1002/jmv.10282

Nasopharyngeal carcinoma, a malignancy associated closely with Epstein‐Barr virus (EBV), is prevalent among Chinese of Southern China origin. Epidemiological studies indicate a high prevalence of EBV in Asia with viral isolates having typical characteristics of the putative viral oncogene, latent membrane protein 1 (LMP‐1), such as the loss of the Xho1 restriction site in Exon 1 and the 30‐bp deletion in Exon 3. The EBV LMP‐1 gene from throat washings of 120 nasopharyngeal carcinoma patients and 14 healthy individuals were analyzed. Similar analyses were also carried out on 30 and 12 postnasal space biopsies from nasopharyngeal carcinoma patients and healthy individuals, respectively. The 30‐bp deletion was detected in 20% of nasopharyngeal carcinoma throat washes and in 100% of nasopharyngeal carcinoma postnasal space biopsies. Interestingly, 16% of the nasopharyngeal carcinoma biopsies possessed both the deleted and the undeleted variants, suggestive of dual infections. The notion of dual infections in nasopharyngeal carcinoma was further supported by the coexistence of both “F” and “f” (BamH1F region) EBV variants in 11% of the nasopharyngeal carcinoma biopsies. All of the throat washes and biopsies from the healthy controls showed the undeleted variant. The loss of the Xho1 restriction site was found with higher frequency both in throat washes and biopsies from patients with nasopharyngeal carcinoma. The discrepancy in the frequency of the 30‐bp deletion between throat washes (20%) and postnasal space biopsies (100%) was an indication that this deletion is specific for viral isolates from primary tumour sites. J. Med. Virol. 69:251–257, 2003. © 2003 Wiley‐Liss, Inc.