Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan, 410008, PR China.
BMC Med Genomics. 2012 Dec 6;5:62. doi: 10.1186/1755-8794-5-62.
Mitochondrial proteomic alterations of nasopharyngeal carcinoma metastasis remain unknown. Our purpose is to screen mitochondrial proteins for the elucidation of the molecular mechanisms of nasopharyngeal carcinoma metastasis and the discovery of metastasis-related biomarkers.
Mitochondria were isolated from nasopharyngeal carcinoma metastatic (5-8F) and nonmetastatic (6-10B) cell lines, respectively. After characterization of isolated mitochondria, mitochondrial differentially expressed proteins (DEPs) were quantified by two-dimensional difference in-gel electrophoresis (2D-DIGE), and identified by peptide mass fingerprint (PMF) and tandem mass spectrometry (MS/MS). A functional enrichment analysis and a protein-protein interaction sub-network analysis for DEPs were carried out with bioinformatics. Furthermore, siRNAs transient transfections were used to suppress expressions of some up-regulated DEPs in metastatic cells (5-8F), followed by Transwell Migration assay.
Sixteen mitochondrial DEPs including PRDX3 and SOD2 were identified. Those 5-8F cells with suppression of PRDX3 showed an increased mobility potential. The functional enrichment analyses of DEPs discovered five significant biological processes including cellular response to reactive oxygen species, hydrogen peroxide metabolic process, regulation of mitochondrial membrane potential, cell redox homeostasis and oxidation reduction, and five significant molecular functions including oxidoreductase activity, caspase inhibitor activity, peroxiredoxin activity, porin activity and antioxidant activity. A protein-protein interaction sub-network of DEPs was generated with literature data. Ten mitochondrial DEPs including PRDX3, PRDX6, SOD2, ECH1, SERPINB5, COX5A, PDIA5, EIF5A, IDH3B, and PSMC4 were rationalized in the tumor-stroma co-evolution model that mitochondrial oxidative stress directly contributes to tumor metastasis.
Sixteen mitochondrial DEPs were identified with mass spectrometry and ten of them were rationalized in the tumor-stroma co-evolution model. Those 5-8F cells with suppression of PRDX3 showed an increased mobility potential. These data suggest that those mitochondrial DEPs are potential biomarkers for NPC metastasis, and their dysregulation would play important roles in mitochondria oxidative stress-mediated NPC metastatic process.
鼻咽癌转移中线粒体蛋白质组的改变尚不清楚。我们的目的是筛选线粒体蛋白，以阐明鼻咽癌转移的分子机制，并发现转移相关的生物标志物。
分别从鼻咽癌转移（5-8F）和非转移（6-10B）细胞系中分离线粒体。分离的线粒体特征描述后，通过二维差异凝胶电泳（2D-DIGE）定量分析线粒体差异表达蛋白（DEPs），并用肽质量指纹图谱（PMF）和串联质谱（MS/MS）鉴定。利用生物信息学对 DEPs 进行功能富集分析和蛋白质-蛋白质相互作用子网络分析。此外，使用 siRNA 瞬时转染抑制转移性细胞（5-8F）中一些上调的 DEPs 的表达，然后进行 Transwell 迁移实验。
鉴定出包括 PRDX3 和 SOD2 在内的 16 个线粒体 DEPs。抑制 PRDX3 的 5-8F 细胞表现出更强的迁移能力。DEPs 的功能富集分析发现了包括细胞对活性氧的反应、过氧化氢代谢过程、线粒体膜电位调节、细胞氧化还原平衡和氧化还原、氧化还原酶活性、半胱氨酸蛋白酶抑制剂活性、过氧化物酶活性、孔蛋白活性和抗氧化活性在内的五个重要生物学过程，以及包括过氧化物酶活性、半胱氨酸蛋白酶抑制剂活性、过氧化物酶活性、孔蛋白活性和抗氧化活性在内的五个重要分子功能。利用文献数据生成了 DEPs 的蛋白质-蛋白质相互作用子网络。十个线粒体 DEPs 包括 PRDX3、PRDX6、SOD2、ECH1、SERPINB5、COX5A、PDIA5、EIF5A、IDH3B 和 PSMC4，被纳入肿瘤-基质共同进化模型，该模型表明线粒体氧化应激直接促进肿瘤转移。
利用质谱技术鉴定出 16 个线粒体 DEPs，其中 10 个在肿瘤-基质共同进化模型中得到了合理的解释。抑制 PRDX3 的 5-8F 细胞表现出更强的迁移能力。这些数据表明，这些线粒体 DEPs 是 NPC 转移的潜在生物标志物，其失调将在线粒体氧化应激介导的 NPC 转移过程中发挥重要作用。
