5-aza-2-dC处理鼻咽癌细胞前后的差异蛋白质组学研究

目的：比较5-杂氮-2′-脱氧胞苷（5-aza-2-dC）处理鼻咽癌细胞前后蛋白质组的差异，为筛选鼻咽癌的甲基化失活基因提供依据。方法：用去甲基化药物5-aza-2-dC处理鼻咽癌细胞系5-8F细胞，应用双向凝胶电泳（2-DE）技术分离5-aza-2-dC处理与未处理5-8F细胞的蛋白质，PDQuest图像分析软件识别药物处理与未处理5-8F细胞的差异表达蛋白质点，基质辅助激光解吸电离飞行时间质谱（MALDI-TOF-MS）鉴定差异表达的蛋白质。Western 印迹法检测差异蛋白质nm23-H1在药物处理与未处理5-8F细胞中的表达水平。结果：建立了5-aza-2-dC处理与未处理5-8F细胞蛋白质的2-DE图谱，识别了49个差异表达的蛋白质点，鉴定了33个差异表达的蛋白质，其中15个蛋白质在5-aza-2-dC处理5-8F后表达上调。Western 印迹分析证实了nm23-H1在药物处理与未处理5-8F细胞中的差异表达水平。结论：15个5-aza-2-dC处理后表达上调蛋白质的编码基因可能是5-8F细胞的甲基化沉默基因。

Differential proteomic analysis of 5-aza-2-dC treatedand untreated nasopharyngeal carcinoma cells

ObjectiveTo compare the proteome difference between nasopharyngeal carcinoma (NPC) cell line 5-8F cells treated and untreated with 5-aza-2-dC, and to provide experimental evidences for screening methylation silenced genes in NPC. MethodsTwo-dimensional gel electrophoresis (2-DE) was performed to separate proteins from treated and untreated 5-8F cells with 5-aza-2-dC, a demethylation agent. PDQuest software was used to analyze 2-DE images, and MALDI-TOF-MS was used to identify the differentially expressed proteins between the 2 groups of 5-8F cells. The expression levels of differential protein nm23-H1 in the 2 groups of 5-8F cells lines were detected by Western blotting. Results2-DE reference patterns of treated and untreated 5-8F cells with 5-aza-2-dC were established. Forty-nine differential protein spots were found between the 2 groups of 5-8F cells, a total of thirty-three non-redundant proteins were identified by MALDI-TOF-MS, and 15 proteins of them were up-regulated after 5-aza-2-dC treatment. The differential expression level of nm23-H1 in the 2 groups of 5-8F cells were confirmed by Western blotting. ConclusionEncoding genes of 15 up-regulated proteins after 5-aza-2-dC treatment may be methylation silenced genes in NPC cell line 5-8F cells.