肾母细胞瘤患儿血清蛋白质标记物的筛选及鉴定

Screening and identification analysis of serum protein biomarkers in nephroblastoma

目的筛选肾母细胞瘤患儿特异性血清蛋白质标记物并对其进行鉴定，以确定其作为肾母细胞瘤血清学诊断和预后监测的特异标志物。方法应用表面增强激光解吸电离飞行时间质谱（SELDI—TOF—MS）技术检测肾母细胞瘤患儿手术前后及正常小儿的血清蛋白质组，筛选差异蛋白质峰，并对目标蛋白质进行分离纯化、酶解，采用液质联用串联质谱（LC—MS／MS）分析，用SEQUST检索程序查询美国Bioworks公司提供的蛋白质序列数据库。结果经SELDI—TOF—MS技术筛选出m／z位于6455．5和6984．4的蛋白质标志物在肾母细胞瘤组低表达（表达强度为1029±364、297±126），正常小儿组高表达（2108±837、753±226），差异均有统计学意义（均P〈0．01）；m／z位于9190．8的蛋白质标志物在肾母细胞瘤术前组低表达（283±154），术后组和正常小儿组高表达（5974±657、6231±519）差异均有统计学意义（均P〈0．01）。对m／z位于6455．5和9190．8的标志物进行鉴定，结果分别为载脂蛋白CⅢ和触珠蛋白。结论检测血清中载脂蛋白CⅢ和触珠蛋白含量可能成为肾母细胞瘤的血清学诊断、恶性度分级和预后监测指标，值得进一步研究与应用。

Objective To screen and characterize the serum protein biomarkers in nephroblastoma so as to establish the proteins as the specific serum biomarkers for diagnosis and prognosis monitoring. Methods The differential protein peaks were located by detecting serum samples of preoperative and postoperative patients and normal children using the SELDI-TOF MS technology. After purification, the differential proteins were further analyzed by LC-MS/MS and the protein sequences searched in database. Results Two peaks with m/z of 6455.5 and 6984.4 were selected as potential biomarkers. They were weakly expressed in nephroblastoma（ intensity： 1029 ± 364,297 ± 126）but highly expressed in normal individuals （2108 ± 837, 753 ± 226 ）; another peak with m/z of 9190. 8 was weakly expressed in preoperative sera（283 ± 154） but highly expressed in serum samples of postoperative patients and normal children（5974 ±657, 6231 ±519）. The protein at 6455.5 and 9190. 8 were identified as apolipoprotein C-Ⅲ and haptoglohlin respectively. Conclusion The detection of differentially expressed apolipoprotein C-Ⅲ and haptoglohlin may have potential utilities for serum diagnosis, malignancy classification and prognosis monitoring of nephrohlastoma and is worthy of further studies and applications.