胰腺癌细胞转染hSSTR2基因对下游波形蛋白表达的影响及其意义

目的 探讨生长抑素2型受体(Hsstr2)基因转染胰腺癌细胞对下游蛋白表达的影响及其意义.方法 利用腺病毒载体Ad.CMV.Hsstr2.GFP将Hsstr2全长Cdna导入胰腺癌细胞Panc-1;采用荧光差异双向凝胶电泳技术分离并筛选Hsstr2基因转染胰腺癌细胞前后差异表达蛋白;用反射式基质辅助激光解吸附电离串联飞行时间质谱鉴定差异蛋白.利用免疫印迹验证差异表达的波形蛋白;采用免疫组化检测波形蛋白在胰腺癌组织中的表达,并分析其临床意义.结果 有统计学意义的差异蛋白质点21个;选择1.3倍以上的差异点18个,经质谱鉴定得到13个蛋白质,包括翻译调节蛋白、代谢酶类、与细胞通讯信号传导相关蛋白、细胞结构蛋白、分子伴侣、具有GTPase活性的蛋白及动力蛋白等.波形蛋白在胰腺癌细胞转染Hsstr2基因后表达降低,免疫组化显示波形蛋白主要在低分化的胰腺癌细胞中高表达.结论 筛选的波形蛋白等差异蛋白可能成为新的胰腺癌敏感治疗靶点.波形蛋白也可能成为预测肿瘤恶性程度的一个指标.

Effect of hSSTR2 gene fransfection on expression of vimentin in pancreatic cancer cells in vitro and its clinical significance

Objective:To study the effects of hSSTR2 gene transfection for downstream proteins in pancreatic cancer cells Panc-1 in vitro and its clinical significance.Methods:The full length hSSTR2 cDNA was introduced into pancreatic cancer cell line Panc-1 by adenovirus mediated transfection.Comprehensive analyses of proteins were focused on total protein spots exhibiting statistical alternations between the experimental group and vector control by fluorescent two-dimensional difference gel electrophoresis analysis.Proteins were identified by peptide mass fingerprinting with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.Western blotting was performed to verify the differential expression of vimentin.Immunohistochemistry was performed to detect the expression of vimentin in pancreatic carcinoma tissue, and its clinical significance was analyzed.Results:There were 21 statistically significant different protein spots.Of them, 18 different points were selected(greater then 1.3-fold); of the 18 protein spots,13 proteins including the regulatory proteins of translation, metabolic enzymes, the associated proteins about cell communication and signal transduction, the cell structural proteins, molecular chaperones, the proteins with the GTPase activity, and power protein were identified by mass spectrometry.Western blot results revealed that the downregulation of vimentin in pancreatic cancer cells with transfected hSSTR2 gene.Immunohistochemistry results revealed that vimentin was highly expressed in poorly differentiated pancreatic cancer cells.Conclusions:These differential expressed proteins, such as vimentin, may serve as new sensitive therapeutic targets in pancreatic cancer.Vimentin may also serve as a biomarker for predicting the degree of malignancy of pancreatic cancer.