Kuefer M U, Look A T, Pulford K, Behm F G, Pattengale P K, Mason D Y, Morris S W
Department of Experimental Oncology, St Jude Children's Research Hospital, Memphis, TN 38105-2794, USA.
Blood. 1997 Oct 15;90(8):2901-10.
Approximately 5% to 10% of all non-Hodgkin's lymphomas contain a t(2;5)(p23;q35) chromosomal rearrangement, which we have previously shown results in the generation of the fusion protein nucleophosmin-anaplastic lymphoma kinase (NPM-ALK). To assess the transforming potential of NPM-ALK in an animal model, we infected 5-fluorouracil-treated murine bone marrow using retroviral stocks and transplanted this infected marrow into lethally irradiated BALB/cByJ mice. Male mice were transplanted with bone marrow from female donors at 10 weeks of age, with 7 of the animals receiving marrow infected with a retroviral construct, pSR alphaMSVtkneo-NPM-ALK, that contains the human NPM-ALK cDNA, and 4 serving as a control group, receiving "empty" pSR alphaMSVtkneo-infected marrow. Whereas all mice in the control group were alive and well up to 11 months after transplantation, 4 of the 7 mice transplanted with marrow containing the NPM-ALK construct developed lymphoma within 4 to 6 months. Tumors arose in the mesenteric lymph nodes, with metastases to the lungs, kidneys, liver, spleen, and the paraspinal area. When cells from the tumors and bone marrow were transplanted into sublethally irradiated secondary recipients, 10 of these 13 mice developed tumors within 9 months. Immunoblot analysis of cell lysates using an ALK polyclonal antibody showed NPM-ALK expression in all tumors examined. Histologically, the tumors were composed of a uniform population of large immunoblastic cells with basophilic cytoplasm, centrally placed nuclei, and distinct nucleoli. Genotypic analysis showed that the tumors were B-lineage and clonal, with rearrangements of the Ig heavy- and kappa light-chain loci and no rearrangements of the T-cell receptor beta locus. Immunocytochemical studies confirmed the presence of IgM heavy chains and kappa light chains within the tumor cells. Thus, in this retroviral gene transfer model, NPM-ALK expression in mice causes B-lineage large-cell lymphoma, suggesting a direct causative role for this activated fusion tyrosine kinase in human lymphoma.
大约5%至10%的非霍奇金淋巴瘤含有t(2;5)(p23;q35)染色体重排，我们之前已经表明，这种重排会导致融合蛋白核磷蛋白-间变性淋巴瘤激酶（NPM-ALK）的产生。为了在动物模型中评估NPM-ALK的转化潜能，我们使用逆转录病毒储备感染经5-氟尿嘧啶处理的小鼠骨髓，并将这种感染的骨髓移植到经致死剂量照射的BALB/cByJ小鼠体内。雄性小鼠在10周龄时接受来自雌性供体的骨髓移植，其中7只动物接受感染了逆转录病毒构建体pSR alphaMSVtkneo-NPM-ALK的骨髓，该构建体包含人NPM-ALK cDNA，4只作为对照组，接受“空的”pSR alphaMSVtkneo感染的骨髓。对照组的所有小鼠在移植后11个月内都存活良好，而7只移植了含NPM-ALK构建体骨髓的小鼠中有4只在4至6个月内发生了淋巴瘤。肿瘤出现在肠系膜淋巴结，并转移至肺、肾、肝、脾和椎旁区域。当将肿瘤细胞和骨髓细胞移植到经亚致死剂量照射的二级受体中时，这13只小鼠中有10只在9个月内发生了肿瘤。使用ALK多克隆抗体对细胞裂解物进行免疫印迹分析显示，在所检测的所有肿瘤中均有NPM-ALK表达。从组织学上看，肿瘤由一群均匀的大免疫母细胞组成，这些细胞具有嗜碱性细胞质、位于中央的细胞核和明显的核仁。基因分型分析表明，肿瘤为B细胞系且具有克隆性，伴有Ig重链和κ轻链基因座重排，而T细胞受体β基因座无重排。免疫细胞化学研究证实肿瘤细胞内存在IgM重链和κ轻链。因此，在这个逆转录病毒基因转移模型中，小鼠体内NPM-ALK的表达会导致B细胞系大细胞淋巴瘤，这表明这种活化的融合酪氨酸激酶在人类淋巴瘤中具有直接的致病作用。
