Background: As a tumor metastasis suppressor gene, the functions of nm23-H1 gene are still unclear. The aim of this study is to better understand the mechanism of lung cancer metastasis and to find new biomarkers for early diagnosis and new target for therapy by conducting comparative proteomics between the human high-metastatic large cell lung cancer cell lines (L9981) and L9981-nm23-H1 (constructed with transfecting nm23-H1 gene into the L9981 cell line).
Methods: The total proteins of L9981 and L9981-nm23-H1 were separated by immobilized pH gradient (IPG)-based 2-dimensional electrophoresis (2-DE); the significantly differently expressed proteins were examined by mass spectrometry and analyzed by bioinformatics.
Results: It was observed that nm23-H1 gene transfection caused remarkable changes of the proteome of L9981 compared with L9981-nm23-H1 cells: 5 proteins were deleted, 9 proteins appeared, 16 proteins downregulated, and 12 proteins up-regulated. These proteins are involved in cell framework, signal transduction, metabolism, proliferation and metastasis.
Conclusions: After nm23-H1 gene is transfected into L9981, proteome in L9981 is remarkably changed. These changes of the proteome could serve as a basis for reversing the invasive and metastatic phenotype in lung cancer and elucidating the mechanisms of the metastasis of lung cancer.
背景与目的: 肿瘤转移抑制基因nm23-H1基因调控肺癌细胞转移潜能的确切机理尚未明了，本研究旨在探讨人高转移大细胞肺癌细胞株（L9981）和转染nm23-H1基因的人高转移大细胞肺癌细胞株（L9981-nm23-H1）的差异表达蛋白，为阐明肺癌转移的分子机制、发现早期诊断肺癌转移的分子标志和新的治疗靶点提供实验依据。
方法: 应用固相pH梯度双向凝胶电泳分离L9981和L9981-nm23-H1细胞株的总蛋白，对25个差异明显的蛋白质点进行质谱鉴定和生物信息学分析。
结果: 研究观察到nm23-H1基因转染使人L9981细胞株蛋白质组的表达谱发生了明显变化：5个蛋白质表达缺失，9个新的蛋白表达，16个蛋白质表达下调，12个蛋白质表达上调。这些蛋白质主要涉及细胞骨架蛋白、信号转导蛋白、细胞代谢相关蛋白、发育增殖相关蛋白及肿瘤侵袭相关蛋白。
结论: nm23-H1基因转染L9981后，蛋白质表达谱发生了显著的变化，这些差异蛋白质可能是逆转肺癌侵袭转移的生化基础，本研究结果可能为阐明肺癌转移的分子机制提供线索。