Analysis of the biojogicel effect of the nudeophcsmin gene mutation on development and progression of leukemia

约30%的急性髓系白血病（AMC）患者存在核磷蛋白（NPMI）基因突变，该基因突变与AMC的完全缓解率和长期生存率密切相关。此外，据报道，NPM 1基因的低表达水平导致骨髓增生异常综合征（MDS）的发展。因此，NPM似乎在AML和MDS的发生和进展中起重要作用。迄今为止，据报道，几种遗传改变与白血病发生有关。重要的是，NPM1基因突变与FLT3突变密切相关。本研究从FLT3基因突变的角度分析突变型NPM在白血病发生、发展中的分子机制，主要研究结果如下：1.建立了稳定表达野生型或突变型NPM 1的32D细胞系。2.建立了共表达FLT3和NPM1的32D细胞系。表达突变型FLT3的32D细胞表现出IL 3非依赖性生长，而额外表达野生型或突变型NPM 1不影响增殖速率和G-CSF诱导的分化。几种抗白血病药物和FLT3激酶抑制剂在表达FLT3和野生型NPM1-ca的32D细胞中的生长抑制作用低于FLT3和突变型NPM1-ca。4.晚期MDS细胞中NPM 1 mRNA表达水平较低。这些抗体可用于蛋白质印迹和免疫组织化学。利用这些抗体，我们发现突变的NPM不仅存在于细胞质中，也存在于核仁外的细胞核中

Mutation of the nucleophosmin(NPMI) gene is found in about 30% of acute myeloid leukemia(AMC) patients, and is closely associated with the cemplete remission rate and a long-term survival rate. In addition, it has been reported that lower expression level of the NPM1 gene causes the development of myelodysplastic syndrome (MDS). Therefore, NPM seems to play an important role for the development and progression of AML and MDS. To date, several genetic alterations have been reportedly involved in the leukemogenesis. Importantly, the NPM1 gene mutation is closely asmciated with the FLT3 mutations. In this study we analyzed the molecular mechanism of mutant NPM for the development and progression of leukemia in the association with FLT3 gene mutations and found the following results.1.We established the stably wild type or mutant NPM1-expressing 32D cell lines. Both cell lines did not show the 113 independent growth, and the proliferation rates were same.2.Next we established the FLT3 and NPM1 coexpressing 32D cell lines. Mutant FLT3-expressing 32D cells showed IL3-independent growth, while additional expressing of wild type or mutant NPM1 did not affect the proliferation rate and G-CSF-induced differentiation.3.However, growth inhibitory effects of several anti-leukemia agents and FLT3 kin ace inhibitors were lower in FLT3 and wild type NPM1-caexpressing 32D cells than FLT3 and mutant NPM1-coexpreccing cells.4.Expression level of NPM1 mRNAis lower in the advanced stage MDS cells.5.We generated wild type or mutant NPM specific antibodies. These antibodies can be used both in western blot and immunohistochemistry. By using these antibodies, we found mutant NPM exists in nucleus outside nucleoli as well as cytoplasma