Feng Wen-hai, Cohen Jeffrey I, Fischer Steven, Li Li, Sneller Michael, Goldbach-Mansky Raphael, Raab-Traub Nancy, Delecluse Henri-Jacques, Kenney Shannon C
Department of Medicine and Microbiology and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill 27599-7295, USA.
J Natl Cancer Inst. 2004 Nov 17;96(22):1691-702. doi: 10.1093/jnci/djh313.
Patients with rheumatoid arthritis or polymyositis treated with methotrexate (MTX) develop Epstein-Barr virus (EBV)-positive lymphomas more frequently than patients treated with other, equally immunosuppressive regimens. Here we determined whether MTX, in contrast to other commonly used medications for rheumatoid arthritis or polymyositis, is unique in its ability to induce the release of infectious EBV from latently infected cells.
The effect of MTX and other immunosuppressant drugs on EBV replication in vitro was assessed using latently infected EBV-positive lymphoblastoid and gastric carcinoma cell lines. Inhibitors of signal transduction pathways were used to define requirements for induction of lytic infection. Drug effects on transcription of the two EBV immediate-early promoters (BRLF1 and BZLF1) and on promoter constructs lacking cis-acting sequences required for activation by other effectors was examined using reporter gene assays. EBV viral load in rheumatoid arthritis and polymyositis patients receiving MTX was compared with that in patients receiving other immunosuppressive medications. Statistical tests were two-sided.
MTX activated the release of infectious EBV from latently infected cell lines in vitro, and MTX treatment was associated with activation of the two viral immediate-early promoters in reporter gene assays. Induction of lytic EBV infection by MTX required the p38 MAP kinase, PI3 kinase, and MEK pathways and specific cis-acting motifs in the two viral immediate-early promoters. Patients treated with MTX-containing regimens had statistically significantly higher mean EBV loads in their blood than patients treated with immunosuppressing regimens that did not include MTX (40 EBV copies per 10(6) cellular genomes versus 5.1 copies; geometric mean fold difference in copies = 10.8, 95%, confidence interval = 3.0 to 38; P = .011).
MTX may promote EBV-positive lymphomas in rheumatoid arthritis and polymyositis patients by its immunosuppressive properties as well as by reactivating latent EBV.
与接受其他同等免疫抑制方案治疗的患者相比，接受甲氨蝶呤（MTX）治疗的类风湿关节炎或多发性肌炎患者更易发生爱泼斯坦-巴尔病毒（EBV）阳性淋巴瘤。在此，我们确定与类风湿关节炎或多发性肌炎的其他常用药物相比，MTX在诱导潜伏感染细胞释放传染性EBV的能力方面是否具有独特性。
使用潜伏感染的EBV阳性淋巴母细胞系和胃癌细胞系评估MTX和其他免疫抑制药物对体外EBV复制的影响。信号转导通路抑制剂用于确定诱导裂解感染的条件。使用报告基因检测法检测药物对两个EBV立即早期启动子（BRLF1和BZLF1）转录以及对缺乏其他效应物激活所需顺式作用序列的启动子构建体的影响。将接受MTX治疗的类风湿关节炎和多发性肌炎患者的EBV病毒载量与接受其他免疫抑制药物治疗的患者进行比较。统计检验为双侧检验。
MTX在体外激活了潜伏感染细胞系中传染性EBV的释放，并且在报告基因检测中MTX治疗与两个病毒立即早期启动子的激活相关。MTX诱导EBV裂解感染需要p38丝裂原活化蛋白激酶、磷脂酰肌醇-3激酶和丝裂原活化蛋白激酶/细胞外信号调节激酶通路以及两个病毒立即早期启动子中的特定顺式作用基序。接受含MTX方案治疗的患者血液中的平均EBV载量在统计学上显著高于接受不包括MTX的免疫抑制方案治疗的患者（每10⁶细胞基因组中EBV拷贝数为40个，而后者为5.1个；拷贝数的几何平均倍数差异=10.8，95%置信区间=3.0至38；P = 0.011）。
MTX可能通过其免疫抑制特性以及重新激活潜伏的EBV来促进类风湿关节炎和多发性肌炎患者发生EBV阳性淋巴瘤。
