August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, 5 Ratsupites Str, 1067 Riga, Latvia.
Latvian Biomedical Research and Study Centre, 1 Ratsupites Str k-1, 1067 Riga, Latvia.
Viruses. 2018 May 3;10(5):239. doi: 10.3390/v10050239.
CCR2 is the cognate receptor to the chemokine CCL2. CCR2⁻CCL2 signaling mediates cancer progression and metastasis dissemination. However, the role of CCR2⁻CCL2 signaling in pathogenesis of B-cell malignancies is not clear. Previously, we showed that CCR2B was upregulated in ex vivo peripheral blood B cells upon Epstein‒Barr virus (EBV) infection and in established lymphoblastoid cell lines with the EBV latency III program. EBV latency III is associated with B-cell lymphomas in immunosuppressed patients. The majority of EBV-positive Burkitt lymphoma (BL) tumors are characterized by latency I, but the BL cell lines drift towards latency III during in vitro culture. In this study, the CCR2A and CCR2B expression was assessed in the isogenic EBV-positive BL cell lines with latency I and III using RT-PCR, immunoblotting, and immunostaining analyses. We found that CCR2B is upregulated in the EBV-positive BL cells with latency III. Consequently, we detected the migration of latency III cells toward CCL2. Notably, the G190A mutation, corresponding to SNP CCR2-V64I, was found in one latency III cell line with a reduced migratory response to CCL2. The upregulation of CCR2B may contribute to the enhanced migration of malignant B cells into CCL2-rich compartments.
CCR2 是趋化因子 CCL2 的同源受体。CCR2⁻CCL2 信号转导介导癌症进展和转移扩散。然而,CCR2⁻CCL2 信号在 B 细胞恶性肿瘤发病机制中的作用尚不清楚。先前,我们发现 EBV 感染后,体外外周血 B 细胞中 CCR2B 上调,并且 EBV 潜伏 III 程序的已建立淋巴母细胞系中 CCR2B 上调。EBV 潜伏 III 与免疫抑制患者的 B 细胞淋巴瘤相关。大多数 EBV 阳性伯基特淋巴瘤(BL)肿瘤的特征是潜伏 I,但在体外培养过程中,BL 细胞系向潜伏 III 漂移。在这项研究中,我们使用 RT-PCR、免疫印迹和免疫染色分析评估了具有潜伏 I 和 III 的同基因 EBV 阳性 BL 细胞系中 CCR2A 和 CCR2B 的表达。我们发现,潜伏 III 的 EBV 阳性 BL 细胞中 CCR2B 上调。因此,我们检测到潜伏 III 细胞向 CCL2 的迁移。值得注意的是,在一个潜伏 III 细胞系中发现了与 SNP CCR2-V64I 对应的 G190A 突变,该突变对 CCL2 的迁移反应降低。CCR2B 的上调可能有助于恶性 B 细胞向富含 CCL2 的隔室的迁移增强。