Shi Linan, Zhang Jun, Wu Peng, Feng Kai, Li Jing, Xie Zhensheng, Xue Peng, Cai Tanxi, Cui Ziyou, Chen Xiulan, Hou Junjie, Zhang Jianzhong, Yang Fuquan
Proteomic Platform, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China.
Graduate University of the Chinese Academy of Sciences, Beijing 100101, PR China.
Proteome Sci. 2009 Mar 16;7:7. doi: 10.1186/1477-5956-7-7.
Acute lymphoblastic leukemia (ALL) is a common form of cancer in children. Currently, bone marrow biopsy is used for diagnosis. Noninvasive biomarkers for the early diagnosis of pediatric ALL are urgently needed. The aim of this study was to discover potential protein biomarkers for pediatric ALL.
Ninety-four pediatric ALL patients and 84 controls were randomly divided into a "training" set (45 ALL patients, 34 healthy controls) and a test set (49 ALL patients, 30 healthy controls and 30 pediatric acute myeloid leukemia (AML) patients). Serum proteomic profiles were measured using surface-enhanced laser desorption/ionization-time-of-flight mass spectroscopy (SELDI-TOF-MS). A classification model was established by Biomarker Pattern Software (BPS). Candidate protein biomarkers were purified by HPLC, identified by LC-MS/MS and validated using ProteinChip immunoassays.
A total of 7 protein peaks (9290 m/z, 7769 m/z, 15110 m/z, 7564 m/z, 4469 m/z, 8937 m/z, 8137 m/z) were found with differential expression levels in the sera of pediatric ALL patients and controls using SELDI-TOF-MS and then analyzed by BPS to construct a classification model in the "training" set. The sensitivity and specificity of the model were found to be 91.8%, and 90.0%, respectively, in the test set. Two candidate protein peaks (7769 and 9290 m/z) were found to be down-regulated in ALL patients, where these were identified as platelet factor 4 (PF4) and pro-platelet basic protein precursor (PBP). Two other candidate protein peaks (8137 and 8937 m/z) were found up-regulated in the sera of ALL patients, and these were identified as fragments of the complement component 3a (C3a).
Platelet factor (PF4), connective tissue activating peptide III (CTAP-III) and two fragments of C3a may be potential protein biomarkers of pediatric ALL and used to distinguish pediatric ALL patients from healthy controls and pediatric AML patients. Further studies with additional populations or using pre-diagnostic sera are needed to confirm the importance of these findings as diagnostic markers of pediatric ALL.
急性淋巴细胞白血病（ALL）是儿童常见的癌症形式。目前，骨髓活检用于诊断。迫切需要用于小儿ALL早期诊断的非侵入性生物标志物。本研究的目的是发现小儿ALL潜在的蛋白质生物标志物。
94例小儿ALL患者和84例对照被随机分为一个“训练”组（45例ALL患者，34例健康对照）和一个测试组（49例ALL患者，30例健康对照和30例小儿急性髓细胞白血病（AML）患者）。使用表面增强激光解吸/电离飞行时间质谱（SELDI-TOF-MS）测量血清蛋白质组谱。通过生物标志物模式软件（BPS）建立分类模型。候选蛋白质生物标志物通过HPLC纯化，通过LC-MS/MS鉴定并使用蛋白质芯片免疫测定法进行验证。
使用SELDI-TOF-MS在小儿ALL患者和对照血清中发现共7个蛋白峰（9290 m/z、7769 m/z、15110 m/z、7564 m/z、4469 m/z、8937 m/z、8137 m/z）表达水平存在差异，然后通过BPS在“训练”组中构建分类模型。该模型在测试组中的敏感性和特异性分别为91.8%和90.0%。发现两个候选蛋白峰（7769和9290 m/z）在ALL患者中下调，这些被鉴定为血小板因子4（PF4）和前血小板碱性蛋白前体（PBP）。另外两个候选蛋白峰（8137和8937 m/z）在ALL患者血清中上调，这些被鉴定为补体成分3a（C3a）的片段。
血小板因子（PF4）、结缔组织活化肽III（CTAP-III）和C3a的两个片段可能是小儿ALL潜在的蛋白质生物标志物，可用于区分小儿ALL患者与健康对照及小儿AML患者。需要用更多人群或使用诊断前血清进行进一步研究，以确认这些发现作为小儿ALL诊断标志物的重要性。
