二维电泳及质谱法分离和鉴定胰腺癌差异表达蛋白质

Separation and identification of differentially expressed proteins in pancreatic carcinoma by two-dimen- sional gel electrophoresis and mass spectrometry

目的 通过分离并鉴定胰腺癌组织、癌旁组织和正常胰腺组织的差异表达蛋白质，发现可能用于早期诊断的胰腺癌肿瘤标志物。方法 用双向电泳分离胰腺癌、癌旁和人正常胰腺组织的总蛋白质。对胰腺癌组织中明显差异表达的蛋白点，行质谱鉴定和生物信息学分析。并对鉴定出的部分蛋白质行免疫印迹验证。结果 建立了稳定、重复性好的凝胶蛋白图谱。对分离出的在胰腺癌组织中明显差异表达的20个蛋白点，成功鉴定出11个蛋白点，其中高表达的有6个，包括：galectin-1、SI，P-2、sorcin、3BP-2、BB1和NCC27。Galectin-1和SLP-2在胰腺癌组织中的高表达通过免疫印迹得到验证。结论 胰腺癌组织相对于癌旁、正常胰腺组织蛋白存在明显的表达差异。胰腺癌差异表达蛋白质可能成为用于早期诊断和评价预后的胰腺癌标志物。

Objective To find potential molecular targets for pancreatic cancer diagnostics by analyzing and comparing the proteomes expressed in human pancreatic carcinoma, paracancerous tissues and normal pancreas. Methods The proteins expressed in these tissues were analyzed by the two- dimensional gel electrophoresis. The differentially expressed proteins in tumors were in-gel digested and analyzed by mass spectrometry, and differential expression of some of the identified proteins was further validated by Western blot analysis. Results Protein extracts of individual sample of each type of tissues were separated on 2D gels. By comparison, there were twenty differentially expressed proteins in the tissues of pancreatic cancer. Eleven proteins were successfully identified by ms and six proteins including galectin-1, SLP-2, sorcin, 3BP-2, BB1 and NCC27 were orerexpresed in tumors. The overexpression of galectin-1 and SLP-2 was further confirmed by Western blot analysis. Conclusion Significant discrepancies in protein expression exist between pancreatic cancer tissues, paracancerous tissues and normal tissues. Some of the differentially expressed proteins found by the proteomic approach may be potential molecular targets for pancreatic cancer diagnostics.