Anti-tumor effect of hematopoietic cells carrying the gene of ribonuclease inhibitor
Anti-tumor effect of hematopoietic cells carrying the gene of ribonuclease inhibitor
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DOI：
10.1038/sj.cgt.7700742
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发表时间：
2005-03-01
影响因子：
6.4
通讯作者：
Zhao, BC
中科院分区：
文献类型：
--
作者：
Fu, PF;Chen, JX;Zhao, BC
人核糖核酸酶抑制因子（Human ribonuclease inhibitor，hRI）是一种分子量为50 kDa的酸性蛋白质。能抑制胰腺核糖核酸酶（RNase A）的活性。血管生成素（Angiogenin，Ang）是核糖核酸酶超家族成员之一。它与RNase A有35%的同源性，并具有核糖核酸裂解活性。然而，血管生成素的底物特异性似乎比胰腺RNA酶更受限制。由于Ang是一种重要的血管生成因子，RI是Ang的高效抑制剂，因此可以推测RI可能是一种潜在的抗血管生成药物。本研究旨在探讨将ri基因导入小鼠造血细胞并诱导其表达以阻断实体瘤血管生成的可行性。首先，从人胎盘中克隆了ri的cDNA基因，并插入逆转录病毒载体pLNCX中。将重组载体pLNCX-ri转染逆转录病毒包装细胞PA 317，获得了一个高滴度的病毒克隆。接着，用携带pLNCX-ri的病毒感染从小鼠骨髓分离的造血细胞。然后将受感染的细胞注射到致死辐射的小鼠中。在体内检测RI的表达和贡献。在给予携带ri基因的造血细胞后，将小鼠植入B16黑色素瘤21天。结果显示，对照组肿瘤体积增大，血管化良好。相比之下，用携带ri基因的造血细胞治疗的小鼠肿瘤较小，血管密度相对较低。肿瘤生长抑制率为47%。这项研究表明，潜在的效用的基因治疗系统交付的一种新的抗血管生成剂- hRI。
Human ribonuclease inhibitor (hRI) is an acid protein with a molecular weight of 50 kDa. It can inhibit the activity of pancreatic RNase (RNase A). Angiogenin (Ang) is a member of the ribonuclease super family. It has 35% identity with RNase A and contains ribonucleolytic activity. The substrate specificity of angiogenin seems, however, to be more restricted than that of the pancreatic RNase. Since Ang is an important angiogenic factor and RI is a highly efficient inhibitor of Ang, it can be hypothesized that RI may be a latent antiangiogenic drug. This study focuses on the feasibility of transfecting the ri gene into mice hematopoietic cells and inducing the expression of the ri gene to block the angiogenesis of solid tumors. First, the cDNA gene of the ri from human placenta was cloned and inserted in a retroviral vector, pLNCX. The combined vector pLNCX-ri was transfected into retroviral packaging cells, PA317, and a clone producing a high titer of virus was obtained. Next, isolated hematopoietic cells from mice bone marrow were infected with viruses carrying the pLNCX-ri. The infected cells were then injected into lethally irradiated mice. The expression and the contribution of RI were assayed in vivo. After administration of hematopoietic cells carrying the ri gene, mice were implanted with B16 melanomas for 21 days. The results showed that tumors of control groups became large and well vascularized. In contrast, tumors from mice groups treated with hematopoietic cells carrying the ri gene were small and possessed a relatively low density of blood vessels. The inhibited growth rate of the tumors was 47%. This study demonstrated the potential utility of gene therapy for systemic delivery of a novel antiangiogenic agent - hRI.