Richie E R, Nairn R S, Becker F F
Cancer Res. 1985 Jun;45(6):2802-6.
AKR mice develop spontaneous thymomas after 6 months of age due to a novel class of murine leukemia viruses that are generated by a series of genetic recombinations between endogenous proviral loci. AKR mice also are more susceptible to N-methyl-N-nitrosourea (MNU)-induced thymomas than are low-leukemia-incidence mouse strains. To determine whether virally and chemically induced lymphomagenesis proceeds by similar pathways in AKR mice, spontaneous and MNU-induced thymic lymphomas were analyzed for a DNA restriction linkage generated during spontaneous tumor development by recombination between envelope genes of endogenous murine leukemia proviral loci. DNA from spontaneous thymic lymphomas invariably contained a restriction fragment characteristic of recombinant murine leukemia virus etiology, while four of five MNU-induced thymic lymphomas did not show this restriction linkage. In addition, analysis of lymphocyte differentiation antigen profiles indicated that MNU-induced lymphomas represent a more immature stage of T-cell differentiation than the majority of spontaneous lymphomas. These data suggest that there are fundamental differences in the mechanisms of induction of virally and chemically induced thymic lymphomas in AKR mice.
AKR小鼠在6个月大后会因一类新型鼠白血病病毒而自发产生胸腺瘤，这类病毒是由内源性前病毒基因座之间的一系列基因重组产生的。与低白血病发病率的小鼠品系相比，AKR小鼠对N-甲基-N-亚硝基脲（MNU）诱导的胸腺瘤也更敏感。为了确定在AKR小鼠中病毒诱导和化学诱导的淋巴瘤发生是否通过相似途径进行，对自发和MNU诱导的胸腺淋巴瘤进行了分析，以检测内源性鼠白血病前病毒基因座包膜基因之间重组在自发肿瘤发生过程中产生的DNA限制性连锁。自发胸腺淋巴瘤的DNA始终含有重组鼠白血病病毒病因学特征性的限制性片段，而五分之四的MNU诱导的胸腺淋巴瘤未显示这种限制性连锁。此外，淋巴细胞分化抗原谱分析表明，MNU诱导的淋巴瘤代表的T细胞分化阶段比大多数自发淋巴瘤更不成熟。这些数据表明，在AKR小鼠中，病毒诱导和化学诱导的胸腺淋巴瘤的诱导机制存在根本差异。
