30-bp Deletion in latent membrane protein 1 (LMP-1) oncogene in lymphoepithelial carcinoma of salivary glands

Abstract

Objective: To investigate the 30 bp deletion in LMP-1 in lymphoepithelial carcinoma of salivary glands, and to clarify the deletion rate. Methods: 46 cases of LEC were subjected to PCR examination for the 3′ terminal region of LMP-1 gene, in order to observe the 30 bp deletion. To reduce the influence of unsuccessful DNA extraction from paraffin-embedded tissue sections, a β-actin PCR was performed at the same time. Additionally, DNA sequencing was performed on 1 case without deletion and 1 case with deletion. Results: 4 of 46 specimens were proved to contain no suitable DNA sample by β-actin gene amplification. In the remaining 42 cases, LMP-1 DNA was detected in 35/42 (83.3%) LEC cases. Two kinds of PCR products were found in these 35 cases after further DNA sequencing. 31 cases (88.6%) carried 316 bp product and 4 cases (11.4%) carried 286 bp product. Conclusion: Some LECs of salivary glands carry del-LMP-1. In our study, the deletion rate was 11.4% (4/35).