Proteomic profiling of autoantibodies in patients with esophageal squamous cell carcinoma

为了鉴定与食管癌发生相关的蛋白质，我们通过二维电泳（2-DE）和串联质谱法对16例食管鳞状细胞癌（escc）和配对的非癌组织进行了蛋白质谱分析。在癌变组织中，3个位点的蛋白量显著上调，8个位点的蛋白量显著下调。采用液相色谱-质谱联用/质谱联用（LC-MS/MS）多肽质量指纹图谱（PMF）对斑点进行鉴定，免疫印迹法对斑点进行鉴定。上调的蛋白为原肌球蛋白α 4链、转胶蛋白和丙酮酸激酶。下调的蛋白为血清白蛋白前体、膜联蛋白Al、原肌球蛋白β链、14-3-3蛋白sigma和血清转铁蛋白前体异构体。在所有16例中，免疫印迹证实原肌球蛋白α 4链上调。免疫组织化学证实原肌球蛋白α 4链在ESCC细胞和邻近成纤维细胞中的定位。

To identify proteins associated with esophageal carcinogenesis, we performed protein profiling of 16 esophageal squamous cell carcinomas (ESCCs) and paired non-cancerous tissues by two-dimensional electrophoresis (2-DE) and tandem mass spectrometry. In cancerous tissues, three spots showed significant up-regulation in the amount of protein, while eight spots were significantly down-regulated. The identities of the spots were determined by peptide mass fingerprinting (PMF) with liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) and were confirmed by immunoblotting. The up-regulated proteins were tropomyosin alpha 4 chain, transgelin, and pyruvate kinase. The down-regulated proteins were serum albumin precursor, isoforms of annexin Al, tropomyosin beta chain, 14-3-3 protein sigma and isoforms of serotransferrin precursor. In all 16 cases, up-regulation of the tropomyosin alpha 4 chain was confirmed by immunoblotting. Localization of the tropomyosin alpha 4 chain in ESCC cells and adjacent fibroblasts was confirmed by immunohistochemistry.