TEL／AML1阳性儿童急性淋巴细胞白血病细胞差异蛋白组的质谱分析

Mass Spectrography Analysis of Differential Proteome in Childhood TEL/AML1-Positive Acute Lymphoblastic Leukemia

本研究采用蛋白质组学的方法对不同预后TEL/AML1阳性儿童ALL白血病细胞进行比较蛋白质组分析,探讨儿童ALL此临床亚型的发生发展机制。根据初诊时白细胞数及临床预后对TEL/AML1(+)儿童ALL进行分组(早期复发组、高白细胞组和标危组),通过双向聚丙烯酰胺凝胶电泳技术进行细胞蛋白质凝胶电泳,选取组别差异明显、表达良好的蛋白利用MALDI-TOF-MS生物质谱和电喷雾质谱(ESI-Ms/Ms)进行鉴定分析。结果表明:不同组间TEL/AML1(+)儿童ALL蛋白表达谱存在显著差异(大于2倍或小于0.5倍),早期复发者与标危者和初诊时高白细胞(>100×109/L)者相比,有71个蛋白点表达消失,93个新蛋白点出现,37个蛋白点表达上调,23个蛋白点表达下调;标危病例与初诊时高白细胞者比较,有6个蛋白点表达消失,56个新蛋白点出现,7个蛋白点表达上调,19个蛋白点表达下调。对40个具有组别显著差异性的蛋白表达点进行质谱分析发现,一组组间差异表达的蛋白,如原肌球蛋白、铁蛋白、乳酸脱氢酶A、CRMP1蛋白、烯醇化酶、AKR1B1、抗氧化物酶、钙联接蛋白、HSP家族(HSP86/HSP89/HSP90)、膜联蛋白VI、G22P1等,其中HSP86/HSP89/HSP90仅在早期复发组高表达;铁蛋白、烯醇化酶在早期复发组表达上调,并在危险程度分组中处于逐渐下调趋势;G22P1(DNA双链修复途径的重要成员)在早期复发组表达下调。结论:早期复发组与其他组别存在显著性差异,部分蛋白可能在儿童ALL的发生发展过程中具有重要作用,可能成为个体化治疗的新的分子指标和药物靶点。

The study was aimed to establish differential proteomic expression analysis of two dimensional electrophoresis and mass spectrography ,and to further explore the mechanisms of nosogenesis in childhood TEL/AML1 acute lymphoblastic leukemia. On the basis of initial leukocyte count and prognostic factors, patients enrolled in this study were divided into three risk groups （early relapse, high leukocyte count and standard risk groups）. The proteins of leukemic cells from patients at diagnosis were separated by two-dimensional gel electrophoresis. Spot detection, quantification and alignment were performed with the PDQuest 7.3.0 image analysis software. Differentially expressed spots were analyzed by mass spectrometry for peptide mass finger（PMF） data. The results showed that the significant difference of protein expression profile existed in 3 groups of childhood TEL/AMLl-positive acute lymphoblastic leukemia. Compared with the high leukocyte count and standard risk groups, 71 protein spots disappeared; 93 new protein spots were found; 37 protein spot expressions were up-regulated; 23 protein spots were down-regulated in early relapse group. Compared the high leukocyte count group, 6 protein spots disappeared, 56 new protein spots were found, 7 protein spot expression were up-regulated, 19 protein spot expressions were down-regulated in standard risk group. The identification of 40 differential protein spots by using mass spectrometry revealed some proteins in 3 groups such as tropomyosin, lactotransferrin, lactate dehydrogenase A, CRMP1 protein, alphaenolase, AKR1B1, calnexin precursor, heat shock protein（HSP86/HSP89/HSP90）, annexin VI, G22P1 and so on. Among them the HSP86/HSP89/HSP90 highly expressed only in early reapse group, the lactotransferrin, alphenolase and G22P1 expressions were up-regulated in early relapse group. It is concluded that the protein expression in early relapse group is significant different from the others. Some proteins may be further used in research on leukemia mechanisms. In addition, these analyses may promote the identification of new targets for individualized treatment approaches.