人肺鳞癌组织的比较蛋白质组学研究

目的利用蛋白质组学方法建立人肺鳞癌组织及其癌旁正常支气管上皮组织的差异蛋白质表达谱。方法对20例人肺鳞癌组织和配对的癌旁正常支气管上皮组织进行比较蛋白质组学研究,即利用双向凝胶电泳（2-DE）分离二者总蛋白质后,经图像分析识别差异表达的蛋白,应用基质辅助激光解吸电离飞行时间质谱（MALDI—TOF—MS）鉴定差异蛋白质。结果（1）比较分析20例肺鳞癌及正常配对组织的2-DE图谱,找到差异蛋白质点76个;（2）对68个差异蛋白质点进行了肽质量指纹图分析,鉴定出一些与瘤基因、细胞周期调控、信号转导等有关的肺鳞癌相关蛋白;（3）肺鳞癌相关蛋白mdm2、c-Jun和表皮生长因子受体（EGFR）在人肺鳞癌组织中高表达,而在正常对照中均表达下调,与蛋白质组的分析鉴定结果是一致的。结论成功鉴定了68个肺鳞癌相关蛋白,为进一步筛选用于肺鳞癌诊断、治疗和预后评估的肺鳞癌分子标志物奠定了坚实的基础。

Comparative proteome analysis of human lung squamous cell carcinoma

OBJECTIVE: This study was designed to establish the two-dimensional electrophoresis profiles with high resolution and reproducibility from human lung squamous cell carcinoma tissue and paired tumor-adjacent normal bronchial epithelial tissue, and to identify differential expression of tumor-associated proteins by using proteome analysis. METHODS: Comparative proteome analysis of human lung squamous carcinoma and paired normal bronchial mucosa adjacent to tumors from 20 cases were carried out. Total proteins of the carcinoma tissue and normal bronchial mucosa were separated by means of immobilized pH gradient-based two-dimensional gel electrophoresis (2-DE). The differentially expressed proteins were analyzed and identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). RESULTS: (1) Seventy-six differentially expressed proteins were screened by analyzing the electrophoretic maps of the 20 carcinoma and control mucosa tissues. (2) Sixty-eight differential proteins were identified by peptide mass fingerprinting (PMF). Some proteins were products of oncogenes and others were involved in the regulation of cell cycle and signal transduction. (3) The expression of three proteins mdm2, c-Jun and EGFR, correlated with lung squamous carcinoma, were detected by immunohistochemical staining and Western blot analysis. The results showed that the expression of mdm2, c-Jun and EGFR were up-regulated in lung squamous carcinomas, whereas down-regulated in control normal mucosa. It was consistent with our proteome analysis results. Those results suggested that those proteins may play roles in the carcinogenesis of lung squamous carcinoma. CONCLUSION: sixty-eight differentially expressed proteins were successfully characterized by comparative proteome analysis. Those results may provide scientific foundation for screening the molecular biomarkers which can be used in diagnosis and treatment of lung squamous carcinoma, as well as to improve patients' prognosis and provide a new clue for carcinogenesis research of lung squamous cell carcinoma.