补体因子I表达下调：通过血清蛋白质组分析鉴定出的一种潜在的胃癌抑制蛋白。

Down-regulated expression of complement factor I: a potential suppressive protein for gastric cancer identified by serum proteome analysis.

作者信息

Liu Wentao, Liu Bingya, Xin Lin, Zhang Yi, Chen Xuehua, Zhu Zhenggang, Lin Yanzhen

机构信息

Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University, 197 Ruijin Road II, Shanghai 200025, PR China.

出版信息

Clin Chim Acta. 2007 Feb;377(1-2):119-26. doi: 10.1016/j.cca.2006.09.005. Epub 2006 Sep 14.

DOI:10.1016/j.cca.2006.09.005

PMID:17067565

Abstract

BACKGROUND

Screening tests are needed for gastric cancer. In order to find serologic biomarkers for gastric cancer screening, we used proteomics to search for protein biomarkers that may be detected in serum of gastric cancer patients.

METHODS

Four groups of serum samples (from 20 gastric cancer patients) included pTNM stages I to IV were compared with two control groups of serum samples. The serum samples were first chromatographed using an immunoaffinity column to selectively remove albumin and IgG. Then serum proteins separated by 2-DE and identified by MALDI-TOF/TOF-MS.

RESULTS

There were 3 proteins including complement C4-B precursor, complement factor I (CFI) precursor and haptoglobin precursor were found significantly different between the healthy and gastric cancer patients. Further validation study by Western blot showed that the detection of CFI precursor was under-expressed in gastric cancer sera compared to normal sera (p<0.05), in addition to a declining expression with the advanced pTNM stage from stage I to IV of gastric cancer patients. Area under the receiver operating characteristic (ROC) curve was 0.78 for the expression of CFI precursor (p<0.01).

CONCLUSIONS

2-DE-based serum proteome analysis may be useful in the screening of serum biomarkers for gastric cancer. CFI precursor could aid in the diagnosis and indicate the advancement of gastric cancer.

摘要

背景

胃癌需要进行筛查测试。为了寻找用于胃癌筛查的血清生物标志物，我们使用蛋白质组学来寻找可能在胃癌患者血清中检测到的蛋白质生物标志物。

方法

将四组血清样本（来自20例胃癌患者，包括pTNM分期I至IV期）与两组血清样本对照组进行比较。血清样本首先使用免疫亲和柱进行色谱分离，以选择性去除白蛋白和IgG。然后通过二维电泳分离血清蛋白，并通过基质辅助激光解吸电离飞行时间串联质谱（MALDI-TOF/TOF-MS）进行鉴定。

结果

发现健康人和胃癌患者之间有3种蛋白质存在显著差异，包括补体C4-B前体、补体因子I（CFI）前体和触珠蛋白前体。通过蛋白质印迹法进行的进一步验证研究表明，与正常血清相比，CFI前体在胃癌血清中的检测表达下调（p<0.05），此外，随着胃癌患者从I期到IV期pTNM分期的进展，其表达呈下降趋势。CFI前体表达的受试者工作特征（ROC）曲线下面积为0.78（p<0.01）。