Study on modifying factors in the development of EBV-associated lymphomas

鼻淋巴瘤（NL）和脓胸相关淋巴瘤（PAL）是1998年的研究对象。研究结果表明：(1)近10年韩国的NL频率下降到前15年的50%左右，而日本的NL频率略有下降；(2)联合免疫表型和基因型研究表明，致死性中线肉芽肿型NL是一种自然杀伤（NK）细胞的肿瘤。为了阐明表达EBV潜伏基因的PAL细胞逃避宿主免疫监视的机制，对EBNA 4区CTL表位进行了测序。结果显示，6例PAL病例中有5例发生了CTL表位突变，提示EBV抗原突变参与了PAL的发展。

Nasal lymphoma(NL) and pyothorax-associated lymphoma(PAL) were the subjects in 1998.Results of the study on NL were as follows : (1) frequency of NL in the recent 10 years decreased to about 50% of the previous 15 years in Korea but slight decrease in Japan ; (2) combined immunophenotypic and genotypic studies showed that NL of lethal midline granuloma type is a neoplasia of natural killer(NK) cell.To elucidate the escape mechanism of EBV latent gene expressing PAL cells from host immune surveillance, CTL epitope of EBNA 4 regions was sequenced.The results showed mutations of the CTL epitope in 5 of 6 PAL cases examined, suggesting the mutations of EBV antigens contributed to development of PAL.