Comparison of hypermethylation of BLU and ARF genes in nasal NK/T cell lymphomas

    ZHANG Xiaoª²Hua1, GAO Ziª²Fen2, TAO Qian3

    1Department of Pathology, School of Medicine, Yan¡¯an University, Yan¡¯an 716000, China, 2Department of Pathology, Health Science Center, Peking University, Beijing 100083, China, 3John Hopkins Singapore Tumor Virology Lab, Singapore 117597

    ¡¾Abstract¡¿ AIM: To investigate the hypermethylation of the BLU and ARF promoter in nasal NK/T cell lymphoma from nasopharyngeal mucosa and its roles in tumor genesis and molecular pathological diagnosis. METHODS: Fortyª²seven cases of nasal NK/T cell lymphomas were studied by using methylation specific PCR (MSP). DNA was extracted from 12 frozen tissues and 35 paraffinª²embedded tissues, then treated by sodium bisulfite and PCR amplified by specific primers for methylated versus unmethylated DNA. PCR products were visualized under UV after agarose electrophresis. RESULTS: The hypermethylation of BLU gene promoter was detected in all the 12 frozen tissue cases (100%) and 8 out of 35 paraffineª²embedded tissue cases (23%) by methylated primer and the hypermethylation of ARF was observed in 1 of 20 frozen cases and 3 of 35 paraffineª²embedded cases. The hypermethylation of BLU was more frequent than that of ARF in all the cases. CONCLUSION: These findings suggest that hypermethylation of BLU gene may play a more substantial role than that of ARF gene in molecular mechanism of NK/T cell lymphoma. The detection of BLU methylation can be used as a molecular marker in pathological diagnosis. ......