蛋白组学技术分析不同转移潜能结肠癌细胞株差异表达蛋白

Screening differential protein expressions in colorectal carcinoma cell lines with varying metastatic potentials using proteomic analysis method

目的:应用蛋白质组学技术分析具有不同转移潜能的人结肠癌LoVo和SW480细胞之间差异表达的蛋白,以寻找结肠癌转移早期诊断生物标志物。方法:应用双向凝胶电泳分离具有高转移潜能的LoVo细胞和低转移潜能的SW480细胞的总蛋白质,凝胶银染和考马斯亮蓝染色,建立双向凝胶电泳图谱,经Image Master软件进行图像分析,筛选部分分离较好的差异蛋白质点。应用基质辅助激光解析电离飞行时间质谱(MALDI-TOF)分析部分差异表达的蛋白质点,获取肽质量指纹图谱,Mascot软件搜索NCBInr数据库鉴定蛋白质。结果:筛选出21个差异蛋白质点,成功鉴定出5种差异蛋白质,其中在LoVo细胞株中表达上调的蛋白有埃兹蛋白(Ezrin)、转录延长因子A(transcription elongation factor A)和甘氨酸A/C(lamin A/C),在SW480细胞株中表达上调的蛋白有NM23蛋白[non-metastatic cells 1,protein (NM23A) expressed in isoform a]和(heat shockprotein 8,热休克蛋白8)。结论:研究发现,这些差异蛋白质的功能涉及肿瘤细胞生长、运动、黏附和凋亡等过程,研究结果为寻找结直肠癌转移早期诊断生物标志物提供了理论依据。

Objective： To analyze the differential protein expressions in highly-metastatic eolorectal carcinoma cell lines LoVo and low-metastatic SW480 cells using proteomic analysis method and detect the biological molecule for early diagnosis of metastasis of colo-rectal carcinoma. Methods：Proteins in highly-metastatic LoVo cells and low-metastatic SW480 cells were isolated by two-dimension gel electrophoresis（Two -DE）. Two-DE map was established by gel-silver staining and Coomassie brilliant blue staining. The well differentially expressed protein spots were screened by Image Master imaging. The specific protein spots were identified by peptide mass fingerprints using matrix-assisted laser desorption/time of flight mass spectrometry （ MALDI-TOF/MS ） and through searching NCBInr database using Mascot software. Results：Twenty one differential protein spots were screened and 5 differential proteins were identified. They included Ezrin protein, transcription elongation factor A, and lamin A/C which were up-regulated in LoVo cells and non-metastatic protein expressed in isoform a （NM23A） and heat shock protein 8 （HSPA8） which were up-regulated in SW480 cells. Conclusion： This study has found that the differential proteins are related with tumor growth, migration, adhesion and apoptosis. Our results provide theoretical basis for finding biological markers for early diagnosis of metastasis of eolorectal carcinoma.