[Interaction between Epstein-Barr virus (EBV) gene expression and antibodies to EBV in nasopharyngeal carcinomas].
In situ hybridization using EBERs and BHLF oligonucleotide probes and immunohistochemistry using monoclonal antibodies against LMP1, EBNA2, BZLF1 protein, p53 protein and bcl-2 protein were performed on 56 primary nasopharyngeal carcinomas. EBERs was detected in 46 cases (82%), and LMP in 17 cases (30%), but EBNA2 was not detected. While 30 of 32 cases (94%) in differentiated non-keratinizing carcinoma (NKC) and 16 of 17 cases (94%) in undifferentiated carcinoma (UNPC) showed EBERs, neither 5 cases of squamous cell carcinoma (SCC) nor 2 cases of adenocarcinoma showed EBERs. This finding confirms latent infection of EBV, especially phenotypical latency II, in NKC and UNPC but not in SCC. Bcl-2 protein was positive in 50 cases (89%), but its expression did not depend on expression of LMP1, which did not demonstrate induction of bcl-2 by LMP1 as seen in vitro. Cytoplasmic BZLF1 expression was detected in 18 cases (32%) whereas BHLF was positive only in 6 cases (11%). This suggests dysfunction of BZLF1, which disrupts viral latency despite its expression. p53 protein was positive in 31 cases (55%), and there was a distinct correlation between expression of BZLF1 and p53 protein (p < 0.001). This suggests that the interaction between BZLF1 protein and p53 protein, which inactivate each other, is one of the tumorigenic factors in NPC.
Department of Otorhinolaryngology, School of Medicine, Kanazawa University.
M
M
Furukawa
I
I
Nagayama
S
S
Murono
H
H
Takeshita
T
T
Nishimura
T
T
Yoshizaki
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood*; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000276:immunology; D005260:Female; D015870:Gene Expression; D004854:Herpesvirus 4, Human / Q000235:genetics* / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000235:genetics* / Q000276:immunology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000276:immunology; D015534:Trans-Activators / Q000276:immunology; D016159:Tumor Suppressor Protein p53 / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology
D000914:Antibodies, Viral; C063676:BZLF1 protein, Herpesvirus 4, Human; D004268:DNA-Binding Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D015534:Trans-Activators; D016159:Tumor Suppressor Protein p53; D014764:Viral Proteins