Department of Protein Therapeutic, Celera, Rockville, MD 20850, USA.
Pancreas. 2012 Jan;41(1):84-94. doi: 10.1097/MPA.0b013e3182236385.
There is a clear need for better therapeutics and diagnostics for pancreatic cancer. We aimed to discover plasma membrane-associated proteins overexpressed in pancreatic cancer using quantitative proteomics and apply RNA interference (RNAi) to uncover proteins associated with cancer cell survival.
Cell surface glycoproteins from 5 pancreatic cancer cell lines were isolated, and differential analyses were performed using mass spectrometry and the "normoid" cell line Hs766T as the comparator. For validation, immunohistochemistry was performed on tissues from 10 independent patients and 2 normal donors. Correlation of protein and mRNA expression level was determined, and functional activity characterized using RNAi.
Integrin β6, CD46, tissue factor, and a novel protein, chromosome 14 open reading frame 1, were identified as overexpressed on pancreatic cancer cell lines. Immunohistochemistry demonstrated the 4 targets were overexpressed in 20% to 70% of primary pancreatic tumor specimens. Small interfering RNA knockdown resulted in a reduction of cellular proliferation by inhibiting DNA synthesis, blocking S-phase progression or induction of apoptosis.
By combining a mass spectrometry identification platform and an RNAi validation platform, we have identified a panel of cell surface glycoproteins that not only are overexpressed, but also play a functional role in pancreatic tumor cell survival.
胰腺癌的治疗和诊断方法亟待改进。本研究旨在采用定量蛋白质组学方法寻找在胰腺癌中过表达的质膜相关蛋白，并应用 RNA 干扰（RNAi）技术揭示与癌细胞存活相关的蛋白。
从 5 种胰腺癌细胞系中分离细胞膜糖蛋白，采用质谱分析和“常态”细胞系 Hs766T 作为对照进行差异分析。采用免疫组织化学法对 10 例独立患者和 2 例正常供体的组织进行验证。测定蛋白和 mRNA 表达水平的相关性，并通过 RNAi 来表征其功能活性。
整合素β6、CD46、组织因子和一个新的蛋白——14 号染色体开放阅读框 1 被鉴定为在胰腺癌细胞系中过表达。免疫组织化学分析显示，这 4 个靶标在 20%至 70%的原发性胰腺肿瘤标本中过表达。小干扰 RNA 敲低通过抑制 DNA 合成、阻断 S 期进展或诱导细胞凋亡，导致细胞增殖减少。
通过将质谱鉴定平台和 RNAi 验证平台相结合，我们鉴定了一组质膜糖蛋白，这些蛋白不仅过表达，而且在胰腺肿瘤细胞存活中发挥功能作用。
