通过非标记蛋白质组学技术研究肺腺癌中差异表达蛋白

Profiling differentially expressed proteins in lung adenocarcinoma by label-free proteomics

目的通过非标记蛋白质组学技术研究肺腺癌中蛋白质表达。方法选取北京大学人民医院5例未经治疗的肺腺癌患者,提取肿瘤组织和配对癌旁组织的总蛋白,通过高效液相色谱-质谱联用技术进行质谱分析。质谱原始数据使用Maxquant软件进行查库和非标记定量分析。Maxquant所得的查库文件使用Perseus软件进行分析。肺腺癌肿瘤组织与配对癌旁组织进行配对t检验,筛选出差异表达蛋白后并对差异蛋白进行基因本体论(GO)和京都基因与基因组百科全书(KEGG)通路富集分析,以P<0.05为差异有统计学意义。结果通过数据库比对获得11295条多肽,分别对应于908个蛋白,其中312个蛋白在肺腺癌中存在显著差异表达,110个蛋白表达上调,212个蛋白表达下调。肺癌中上调倍数最高的为铁蛋白,下调倍数最高的为COL6A3。GO分析提示肺腺癌中差异表达的蛋白主要富集的分子功能为RNA binding。KEGG通路分析也证实剪接体通路在差异表达蛋白中显著富集。结论通过非标记蛋白质组学技术发现312个在肺腺癌中显著差异表达的蛋白质。

Objective This study was designed to profile protein expression in lung adenocarcinoma by label-free proteomics.Methods Five treatment-naïve lung adenocarcinoma patients were retrospectively selected,and total protein was extracted from the paired tumor tissues and adjacent normal tissues.The proteins were analyzed by high performance liquid chromatography-mass spectrometry.The raw data of mass spectrometry was blast to database and quantitatively analyzed by MaxQuant software.After blast to database,the MaxQuant generated data were analyzed by Perseus software.The differentially expressed proteins were further subjected to Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways enrichment analyses.P value<0.05 was considered as statistically significant.Results After blast to database,we achieved 11295 unique peptides belonging to 908 proteins.A total of 312 proteins were statistically differentially expressed in lung adenocarcinoma compared with adjacent tissues,and 110 proteins were upregulated,and 212 proteins were downregulated in lung adenocarcinoma.The ferritin was most upregulated in lung adenocarcinoma and collagen alpha-3(VI)chain was most downregulated in lung adenocarcinoma.GO molecular function enrichment analyses showed that the differentially expressed proteins were enriched with function of poly(A)RNA binding and RNA binding.Conclusion By the label-free proteomics approach,we identified 312 differentially expressed proteins in lung adenocarcinoma.