胰腺癌差异蛋白质组学研究

Comparative Proteomics of Pancreatic Cancer

目的通过差异蛋白质组学研究,确定胰腺癌组织及相应正常胰腺组织之间蛋白质表达谱的差异,进而阐明其表达水平的变化与胰腺癌发生发展之间的关系。方法选取胰腺癌组织及相应正常胰腺组织6对,提取总蛋白进行双向聚丙烯酰胺凝胶电泳,经PDQuest软件分析,获得差异表达蛋白质点。差异蛋白质点经过切取、酶解后进行电喷雾四极杆飞行时间质谱(ESI-Q-TOF MS/MS)鉴定。质谱数据使用MASCOT搜索引擎对ExPASy蛋白质序列数据库进行检索,即获得差异表达的蛋白质。对鉴定出的部分蛋白质通过免疫组化方法进行验证。结果经双向凝胶电泳分析共有97个点被确定为差异表达,其中31个点已被成功鉴定,23个蛋白上调,8个蛋白下调。这些蛋白质涉及体内不同的功能过程和蛋白家族,主要包括:糖酵解相关酶,透明质酸酶,Ⅰ、Ⅱ相代谢酶,金属蛋白酶,细胞骨架,Ca2+代谢相关酶等。免疫组化方法进一步证实了HYAL1表达上调,CYP2C8和GSTM2表达下调。结论应用比较蛋白质组学方法可筛选出胰腺癌患者癌组织和正常胰腺组织间存在的差异表达蛋白,筛选出的蛋白将为进一步阐述胰腺癌的发生发展机制提供很好的线索和帮助。

Objective To identify differentially expressed proteins between pancreatic tumor tissues and the adjacent noncancerous tissues by comparative proteomics analysis.Methods Six pairs pancreatic tumor tissues and the adjacent noncancerous tissues were obtained and selected for two-dimensional polyacrylamide gel electrophoresis（2-DE） analysis.The differentially expressed proteins were identified using the PDQuest 2-D analysis software.After cutting and enzymolysis,the differentially expressed proteins were analysised by ESI-Q-TOF mass spectrometer.The MS/MS data were acquired and searched in the Swiss-Prot database using MASCOT software.Altered expression of representative proteins was validated by immunohistochemical staining.Results A total of 97 points were identified as differentially expressed by two-dimensional gel electrophoresis,of which 31 were successfully identified by ESI-Q-TOF mass spectrometer.Among the proteins identified by mass spectrometer,23 were upregulated and the other 8 were downregulated.These proteins were involved in different functional processes and protein families： glucolysis,hyaluronidase,Ⅰ,Ⅱ-phase metabolic enzymes,metalloproteinase,cytoskeleton,Ca2＋ metabolism and so on.Immunohistochemical staining revealed an overexpression of HYAL1 and low expression of CYP2C8 and GSTM2 in pancreatic tumor.Conclusion The differentially expressed proteins between pancreatic tumor tissues and the adjacent noncancerous tissues can be identified by comparative proteomics approach.The selected proteins will provide a valuable clue and help for further research.