两种大肠癌转移性细胞株双向电泳图谱的初步分析

目的 初步分析大肠癌转移过程中差异表达的蛋白质,为阐述大肠癌转移的分子机制提供线索。方法 以一对来自同一亲本、转移能力不同的人大肠癌细胞株SW620和SW480为实验对象,利用双向电泳技术(two-dimensional gel electrophoresis,2-DE),建立并优化两种细胞株的蛋白表达图谱;之后利用Melanieш软件分析与大肠癌转移相关的差异表达蛋白点。结果 两种细胞株的2-DE蛋白表达谱具有良好的重复性和可比性;采用了非线性pH3-10及重叠窄范围的固相pH梯度胶条,提高了2-DE图谱的分辨率;初步选择11个差异表达蛋白点。结论 非线性及重叠窄范围的固相pH梯度胶条可改善2-DE中蛋白分离的效果,初步分离的差异蛋白点为进一步鉴定大肠癌转移相关蛋白及建立大肠癌转移性细胞株的2-DE数据库奠定了基础。

Analysis of protein expression maps of two metastatic colorectal carcinoma cell lines generated by two-dimensional gel electrophoresis

Objective To analyze the differentially expressed proteins in metastatic colorectal carcinoma and provide clues for the molecular mechanisms of colorectal cancer metastasis. Methods A pair of colorectal carcinoma cell lines SW620 and SW480 with different metastatic potentials from the same parent cell lines were studied. The protein expression maps of the two cell lines were obtained and optimized using two-dimensional gel electrophoresis (2-DE), and the differentially expressed protein spots associated with metastasis were analyzed by Melanie ш software. Results The 2-DE expression maps of the two cell lines were well matched. The resolution of 2-DE was increased after using the nonlinear pH3-10 or overlapping narrow immobilized pH gradient strips, and 11 differentially expressed protein spots were identified after analysis using the software. Conclusions Nonlinear pH3-10 and overlapping narrow immobilized pH gradient strips have higher separation efficiency for protein in 2-DE. The differentially expressed proteins separated will be useful for identifying metastasis-associated proteins of colorectal carcinoma and for establishing 2-DE database of the metastatic colorectal carcinoma cell lines.