喉癌细胞中S100A8新的相互作用蛋白质的鉴定

目的探索S100A8相互作用蛋白在喉癌发生、发展中的可能机制。方法应用抗S100A8抗体通过免疫沉淀的方法从喉癌细胞系Hep-2中分离与S100A8相互作用的蛋白质。用基质辅助激光解析电离飞行时间质谱仪分析目的蛋白条带。根据这些目的蛋白条带的肽指纹谱,用Mascot软件预测其相应的蛋白质。用P-Match软件预测这些蛋白质的NF-kappa B结合位点。用免疫共沉淀方法证实其中一个蛋白质与S100A8相互结合的能力。结果获得了4种与S100A8相互作用的新的蛋白质,它们分别是假想蛋白质LOC80154（hypothetical protein LOC80154）、MHCclass Ⅰ HLA-B、T-box1异构体C相似蛋白质（similar to T-box1 isoformC）和肌纤维膜相关蛋白1（sarcolemmal associated protein 1）。这4种蛋白质均具有NF-kappa B的结合位点,其中MHCclass Ⅰ HLA-B是NF-kappa B通路中的一个成员,我们首次证实该蛋白质具有结合S100A8的能力。结论本研究获得的S100A8新的伴侣可能是NF-kappa B通路的成员。MHCclass Ⅰ HLA-B与S100A8的结合提示S100A8可能作为新成员与包括HLA-B在内的其他蛋白质在NF-kappa B通路中发挥作用。这些发现为进一步研究S100A8在喉癌发生中的分子机制提供了新线索。

Novel partners of S100A8 identified in laryngeal cancer cell lines

OBJECTIVE: To explore mechanism of S100A8 in the oncogenesis and development of laryngeal cancer. METHODS: Proteins interacting with S100A8 were isolated from laryngeal cancer cell lines Hep-2 by immunoprecipitation assay with anti-S100A8 antibody. The target bands were cut out and identified by maxtrix assisted laser desorption/ionization time of flight (MALDI-TOF). The peptide mass fingerprinting data of the proteins identified were analyzed based on the Mascot database. The NF-kappa B binding sites of the proteins were predicted by P-Match software. The binding ability of one of the proteins to S100A8 was confirmed by co-immunoprecipitation and immunocytochemistry methods. RESULTS: Four proteins interacting with S100A8 were obtained, which were hypothetical protein LOC80154, MHC class I HLA-B, similar to T-box 1 isoform C and sarcolemmal associated protein 1. The four genes were predicted to have NF-kappa B binding sites. MHC class I HLA-B, which is one of targets in NF-kappa B pathway, was first confirmed to have the binding ability to S100A8. CONCLUSION: The novel partners of S100A8 identified in the study might be involved in NF-kappa B pathway. The binding ability of MHC class I HLA-B to S100A8 implies that S100A8 might function as a new member with other proteins including HLA-B in NF-kappa B pathway. These findings provide a new clue to further study on the molecular mechanism of S100A8 in the genesis of laryngeal carcinomas.