An approach to studying lung cancer-related proteins in human blood.

Abstract

Early stage lung cancer detection is the first step toward successful clinical therapy and increased patient survival. Clinicians monitor cancer progression by profiling tumor cell proteins in the blood plasma of afflicted patients. Blood plasma, however, is a difficult cancer protein assessment medium because it is rich in albumins and heterogeneous protein species. We report herein a method to detect the proteins released into the circulatory system by tumor cells. Initially we analyzed the protein components in the conditioned medium (CM) of lung cancer primary cell or organ cultures and in the adjacent normal bronchus using one-dimensional PAGE and nano-ESI-MS/MS. We identified 299 proteins involved in key cellular process such as cell growth, organogenesis, and signal transduction. We selected 13 interesting proteins from this list and analyzed them in 628 blood plasma samples using ELISA. We detected 11 of these 13 proteins in the plasma of lung cancer patients and non-patient controls. Our results showed that plasma matrix metalloproteinase 1 levels were elevated significantly in late stage lung cancer patients and that the plasma levels of 14-3-3 sigma, beta, and eta in the lung cancer patients were significantly lower than those in the control subjects. To our knowledge, this is the first time that fascin, ezrin, CD98, annexin A4, 14-3-3 sigma, 14-3-3 beta, and 14-3-3 eta proteins have been detected in human plasma by ELISA. The preliminary results showed that a combination of CD98, fascin, polymeric immunoglobulin receptor/secretory component and 14-3-3 eta had a higher sensitivity and specificity than any single marker. In conclusion, we report a method to detect proteins released into blood by lung cancer. This pilot approach may lead to the identification of novel protein markers in blood and provide a new method of identifying tumor biomarker profiles for guiding both early detection and therapy of human cancer.

• Authors: Ting Xiao, Wantao Ying, Lei Li, Zhi Hu, Ying Ma, Liyan Jiao, Jinfang Ma, Yun Cai, Dongmei Lin, Suping Guo, Naijun Han, Xuebing Di, Min Li, Dechao Zhang, Kai Su, Jinsong Yuan, Hongwei Zheng, Meixia Gao, Jie He, Susheng Shi, Wuju Li, Ningzhi Xu, Husheng Zhang, Yan Liu, Kaitai Zhang, Yanning Gao, Xiaohong Qian, Shujun Cheng
• Journal: Molecular & cellular proteomics : MCP (Mol Cell Proteomics) Vol. 4 Issue 10 Pg. 1480-6 (Oct 2005) ISSN: 1535-9476 [Print] United States
• PMID: 15970581 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Culture Media, Conditioned
• Neoplasm Proteins
• Proteome
• Tissue Inhibitor of Metalloproteinase-1
• Collagenases
• MMP13 protein, human
• Matrix Metalloproteinase 13

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Case-Control Studies
• Cells, Cultured
• Collagenases (blood)
• Culture Media, Conditioned (metabolism)
• Databases, Protein
• Enzyme-Linked Immunosorbent Assay
• Humans
• Lung Neoplasms (blood)
• Matrix Metalloproteinase 13
• Middle Aged
• Neoplasm Proteins (blood)
• Proteome (analysis)
• Tissue Inhibitor of Metalloproteinase-1 (blood)