Plasma proteomics of pancreatic cancer patients by multi-dimensional liquid chromatography and two-dimensional difference gel electrophoresis (2D-DIGE): Up-regulation of leucine-rich alpha-2-glycoprot
详细信息 查看全文
- 作者：Tatsuhiko Kakisaka ; Tadashi Kondo ; Tetsuya Okano ; Kiyonaga Fujii ; Kazufumi Honda ; Mitsufumi Endo ; Akihiko Tsuchida ; Tatsuya Aoki ; Takao Itoi ; Fuminori Moriyasu ; et al.
- 关键词：Plasma proteomics ; Pancreatic cancer ; Two-dimensional difference gel electrophoresis (2D-DIGE) ; Leucine-rich alpha-2-glycoprotein
- 刊名：Journal of Chromatography B, Analytical Technologies in the Biomedical and Life Sciences
- 出版年：2007
- 出版时间：1 June 2007
- 年：2007
- 卷：852
- 期：1-2
- 页码：257-267
- 全文大小：1866 K
文摘
We investigated the aberrant expression of plasma proteins in patients with pancreatic cancer. High-abundance plasma proteins (albumin, transferrin, haptoglobin, alpha-1-antitrypsin, IgG and IgA) were depleted by use of an immuno-affinity column, and low-abundance ones were separated into five fractions by anion-exchange chromatography. The fractionated plasma proteins were subjected to 2D-DIGE with highly sensitive fluorescent dyes. The quantitative protein expression profiles obtained by 2D-DIGE were compared between two plasma protein mixtures: one from five non-cancer bearing healthy donors and the other from five patients with pancreatic cancer. Among 1200 protein spots, we found that 33 protein spots were differently expressed between the two mixtures; 27 of these were up-regulated and six were down-regulated in cancer. Mass spectrometry and database searching allowed the identification of the proteins corresponding to the gel spots. Up-regulation of leucine-rich alpha-2-glycoprotein (LRG), which has not previously been implicated in pancreatic cancer, was observed. Western blotting with an anti-LRG antibody validated the up-regulation of LRG in an independent series of plasma samples from healthy controls, patients with chronic pancreatitis, and patients with pancreatic cancer. Our results demonstrate the application of a combination of multi-dimensional liquid chromatography with 2D-DIGE for plasma proteomics and suggest the clinical utility of LRG plasma level measurement.