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. 2010 Sep 19:5:16.
doi: 10.1186/1750-9378-5-16.

Conserved mutation of Epstein-Barr virus-encoded BamHI-A Rightward Frame-1 (BARF1) gene in Indonesian nasopharyngeal carcinoma

Susanna H Hutajulu  1 , Eveline K Hoebe, Sandra Awm Verkuijlen, Jajah Fachiroh, Bambang Hariwijanto, Sofia M Haryana, Servi Jc Stevens, Astrid E Greijer, Jaap M Middeldorp
Affiliations

Conserved mutation of Epstein-Barr virus-encoded BamHI-A Rightward Frame-1 (BARF1) gene in Indonesian nasopharyngeal carcinoma

Susanna H Hutajulu et al. Infect Agent Cancer. .

Abstract

Background: BamHI-A rightward frame-1 (BARF1) is a carcinoma-specific Epstein-Barr virus (EBV) encoded oncogene. Here we describe the BARF1 sequence diversity in nasopharyngeal carcinoma (NPC), other EBV-related diseases and Indonesian healthy EBV carriers in relation to EBV genotype, viral load and serology markers. Nasopharyngeal brushings from 56 NPC cases, blood or tissue from 15 other EBV-related disorders, spontaneous B cell lines (LCL) from 5 Indonesian healthy individuals and several prototype EBV isolates were analysed by PCR-direct sequencing.

Results: Most NPC isolates revealed specific BARF1 nucleotide changes compared to prototype B95-8 virus. At the protein level these mutations resulted in 3 main substitutions (V29A, W72G, H130R), which are not considered to cause gross tertiary structure alterations in the hexameric BARF1 protein. At least one amino acid conversion was detected in 80.3% of NPC samples compared to 33.3% of non-NPC samples (p < 0.001) and 40.0% of healthy LCLs (p = 0.074). NPC isolates also showed more frequent codon mutation than non-NPC samples. EBV strain typing revealed most isolates as EBV type 1. The viral load of either NPC or non-NPC samples was high, but only in non- NPC group it related to a particular BARF1 variant. Serology on NPC sera using IgA/EBNA-1 ELISA, IgA/VCA-p18 ELISA and immunoblot score showed no relation with BARF1 sequence diversity (p = 0.802, 0.382 and 0.058, respectively). NPC patients had variable antibody reactivity against purified hexameric NPC-derived BARF1 irrespective of the endogenous BARF1 sequence.

Conclusion: The sequence variation of BARF1 observed in Indonesian NPC patients and controls may reflect a natural selection of EBV strains unlikely to be predisposing to carcinogenesis. The conserved nature of BARF1 may reflect an important role in EBV (epithelial) persistence.

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Figures

Figure 1
Figure 1
Phylogenetic tree of individual BARF1 gene variants at the nucleotide level (A) and at the amino acid level (B). AIDS: Acquired immune deficiency syndrome; PTLD: post-transplant lymphoproliferative disorder; IM: infectious mononucleosis; BL: Burkitt's lymphoma; NPC-NL: NPC from The Netherlands (Dutch NPC); NHL: non-Hodgkin lymphoma. The scale reflects the evolutionary distance.
Figure 2
Figure 2
Position of 3 typical amino acid changes in BARF1 positioned into the hexameric structure (kindly provided by dr. N.Tarbouriech).
Figure 3
Figure 3
Scatter diagram of EBV DNA load in 53 NPC brushing samples (copies/brushings) (A) and 11 non-NPC other EBV-associated isolates (copies/ml) (B) versus BARF1 amino acid conversion. The Y axis was expressed in a log scale with cutoff value set on 2,300 copies/brushing in NPC brushing and 2,000 copies/ml in other EBV-related isolates as defined before [10]. In NPC group EBV DNA load did not relate to the presence of amino acid conversion while in other EBV-associated diseases it did (one-way ANOVA p = 0.606 and 0.014 respectively).
Figure 4
Figure 4
Boxplot of seroreactivity expressed as normalized OD450 values of NPC sera in IgA/EBNA-1 ELISA (A) and IgA/VCA-p18 ELISA (B) versus BARF1 amino acid conversion. The cutoff value was set on 0.3 [51]. The bar in the boxplot indicates the median value. Serology results did not relate to the presence of variant BARF1 (Mann-Whitney U test p = 0.802 and 0.382 respectively).
Figure 5
Figure 5
Boxplot of seroreactivity expressed as normalized OD450 values of IgG/BARF1 between groups of healthy controls and NPC patients. No difference found in anti-BARF1 response between wild-type and variant BARF1 NPC patients (Mann-Whitney U test p = 0.850).
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References

    1. Cohen JI, Lekstrom K. Epstein-Barr virus BARF1 protein is dispensable for B-cell transformation and inhibits alpha interferon secretion from mononuclear cells. J Virol. 1999;73(9):7627–7632. - PMC - PubMed
    1. Young LS, Rickinson AB. Epstein-Barr virus: 40 years on. Nat Rev Cancer. 2004;4(10):757–768. doi: 10.1038/nrc1452. - DOI - PubMed
    1. Thompson MP, Kurzrock R. Epstein-Barr virus and cancer. Clin Cancer Res. 2004;10(3):803–821. doi: 10.1158/1078-0432.CCR-0670-3. - DOI - PubMed
    1. Middeldorp JM, Brink AA, van den Brule AJ, Meijer CJ. Pathogenic roles for Epstein-Barr virus (EBV) gene products in EBV-associated proliferative disorders. Crit Rev Oncol Hematol. 2003;45(1):1–36. doi: 10.1016/S1040-8428(02)00078-1. - DOI - PubMed
    1. Pathmanathan R, Prasad U, Sadler R, Flynn K, Raab-Traub N. Clonal proliferations of cells infected with Epstein-Barr virus in preinvasive lesions related to nasopharyngeal carcinoma. N Engl J Med. 1995;333(11):693–698. doi: 10.1056/NEJM199509143331103. - DOI - PubMed

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