Department of Virology, Faculty of Medicine, Imperial College London, Norfolk Place, London W2 1PG, UK.
Semin Cancer Biol. 2009 Dec;19(6):366-76. doi: 10.1016/j.semcancer.2009.07.007. Epub 2009 Jul 25.
A defining characteristic of the aggressive B cell tumour Burkitt's lymphoma (BL) is a reciprocal chromosomal translocation that activates the Myc oncogene by juxtaposing it to one of the immunoglobulin gene loci. The consequences of activating Myc include cell growth and proliferation that can lead to lymphomagenesis; however, as part of a fail-safe mechanism that has evolved in metazoans to reduce the likelihood of neoplastic disease, activated oncogenes such as Myc may also induce cell death by apoptosis and/or an irreversible block to proliferation called senescence. For lymphoma to develop it is necessary that these latter processes are repressed. More than 95% of a subset of BL - known as endemic (e)BL because they are largely restricted to regions of equatorial Africa and similar geographical regions - carry latent Epstein-Barr virus (EBV) in the form of nuclear extra-chromosomal episomes. Although EBV is not generally regarded as a driving force of BL cell proliferation, it plays an important role in the pathogenesis of eBL. Latency-associated EBV gene products can inhibit a variety of pathways that lead to apoptosis and senescence; therefore EBV probably counteracts the proliferation-restricting activities of deregulated Myc and so facilitates the development of BL.
侵袭性 B 细胞肿瘤伯基特淋巴瘤（BL）的一个显著特征是一种相互易位，通过将其与免疫球蛋白基因座之一并列，激活 Myc 癌基因。激活 Myc 的后果包括细胞生长和增殖，从而导致淋巴瘤发生；然而，作为后生动物中为降低肿瘤疾病发生可能性而进化出的故障安全机制的一部分，像 Myc 这样的激活癌基因也可能通过细胞凋亡和/或称为衰老的不可逆转增殖阻滞来诱导细胞死亡。为了发展成淋巴瘤，这些后一种过程必须受到抑制。BL 的一个子集 - 称为地方性（e）BL，因为它们主要局限于赤道非洲和类似地理区域 - 超过 95%携带潜伏性 Epstein-Barr 病毒（EBV），形式为核外染色体外体。尽管 EBV 通常不被认为是 BL 细胞增殖的驱动力，但它在 eBL 的发病机制中起着重要作用。潜伏相关 EBV 基因产物可以抑制多种导致凋亡和衰老的途径；因此，EBV 可能会抵消失调 Myc 的增殖抑制活性，从而促进 BL 的发展。
