1. Unraveling the Complex Proteome for Biomarker Discovery in Gastrointestinal and Liver Diseases 
Kenneth Song, Samir Hanash 
Gastroenterology 
Volume 131, Issue 5, Pages (November 2006)
DOI: /j.gastro
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2. Figure 1
Biomarker discovery using proteomics. One or multiple steps may be undertaken for both protein processing and protein analysis. For example, a specimen may have the proteins processed by both labeling with a stable isotope and purifying with a column to analyze only cell-surface proteins.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2006 AGA Institute Terms and Conditions

3. Figure 2
Promising proteomic approaches. (A) Protein microarrays coated either with antibodies or proteins. Red circles represent fluorescent tags that can be detected using a scanner, which are represented by white and red spots on the scanned image. (B) Representative mass ion spectra of a peptide. The heavy labeled peptide is from cancer patient serum and the light labeled peptide is from normal patient serum. Ratio is calculated using total ion intensity. (C) Example of fractionation and isotope labeling of proteins in pancreatic cancer versus control serum. Each row represents a single protein and the columns represent protein fractions based on charge state and hydrophobic properties. Each colored spot identifies the presence of a peptide for that protein in that fraction. Red represents up-regulated in cancer, green is down-regulated in cancer, and yellow is no dysregulation compared with control.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2006 AGA Institute Terms and Conditions

4. Figure 3 Guidelines for biomarker development as set forth by EDRN.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2006 AGA Institute Terms and Conditions