人大肠癌不同转移潜能细胞株SW620及SW480的差异蛋白质组分析

Differential proteomic analysis of human colorectal carcinoma cell lines SW620 and SW480 with different metastatic potentials

目的分析比较人大肠癌不同转移潜能细胞株的差异表达蛋白质图谱,筛选并探讨肿瘤转移相关蛋白与大肠癌发生发展转移的关系.方法利用双向凝胶电泳(2-DE)和基质辅助激光解析离子化-飞行时间-质谱技术,分析高低转移性细胞株SW620和SW480蛋白质图谱的差异表达,查询数据库筛选大肠癌转移相关蛋白质.结果MalenieⅢ软件分析3次相同条件下的2-DE图谱,结果显示重复性、匹配性较好.SW620检测到(1316±62)个蛋白点,平均匹配率82%;SW480检测到(1332±74)个蛋白点,平均匹配率80%;蛋白点分布以PI 4～7、相对分子质量20 000～70 000范围内最多.两种细胞株25个差异蛋白点(SW620 14个、SW480 11个)胰酶胶内酶解、质谱分析获得23张肽质量指纹谱;数据库查询结果高度匹配已知蛋白质3个,初步匹配已知蛋白质或片段14个.在这些差异表达的蛋白质中,部分与基因转录、细胞周期、信号转导、细胞凋亡有关,可能参与大肠癌的分化、增殖、侵袭、黏附和转移等多种生物学行为.结论人大肠癌不同转移潜能细胞株SW620和SW480的2-DE蛋白质图谱具有明显的差异表达,提示大肠癌转移过程的发生是多种蛋白质功能共同作用的结果.

Objective To investigate differential protein expression profiles of human colorectal carcinoma cell lines with different metastatic potentials and screen metastasis-associated proteins for analyzing the relationship between metastasisassociated proteins and the tumorigenesis, progression and metastasis ofcolorectal carcinomas. Methods With two-dimensional electrophoresis （2-DE） and matrix assisted laser desorption/ionization-time of flight-mass spectrometry, we analyzed the differentially expressed proteins in two human colorectal carcinoma cell lines SW620 and SW480 with high and low metastatic potentials, and screened for proteins associated with colorectal carcinoma metastasis. Results Image analysis software Malenie Ⅲ demonstrated good match and reproducibility of the 2-DE maps obtained from 3 independent experiments, with 1316±62 spots detected for SW620 cells and 1332±74 spots for SW480 cells with the average matching rate of 82% and 80%, respectively. The spots distributed in the greatest density at the isoelectric points of 4-7 and relative molecular mass weight of 20 000-70 000. Twenty-five distinctly different protein spots （14 spots for SW620 and 11 for SW480） in-gel digested by TPCK trypsin and 23 peptide mass fingerprint maps were obtained by mass spectrometry. Three highly matched proteins and 14 preliminarily matched proteins or fragments were obtained by analysis with Mascot software in the NCBInr database. Some of these differentially expressed proteins were related to gene transcription, cell cycle, signal transduction, cell apoptosis, etc, with possible involvement of cell differentiation, proliferation, invasion, adhesion, and metastasis of colorectal carcinoma. Conclusion The 2-DE protein expression profile of SW620 cells with high metastatic potential displays obvious difference from that of SW480 cells with low metastatic potential, and a variety of proteins can be involved in the metastasis of colorectal carcinoma.