Quantitative Proteomics in Development of Disease Protein Biomarkers - Proteomic and Metabolomic Approaches to Biomarker Discovery - page 253

with a highlighted discussion of the analyte
complexity and sample throughput aspect of
MS-based proteomics and its implication in the
biomarker development. Literature examples
used are mainly 2008 to 2012; refer to other chap-
ters of the topic for a comprehensive coverage
of the

analyzing different molecules in a single

experiment.

QUANTITATIVE PROTEOMIC
PROFILING FOR PROTEIN
BIOMARKER DISCOVERY

field.
This chapter adopts the terminology used in
arecentreview 2 (1) labeling d stable isotope
labeling; (2) tagging d stable isotope labelingusing
chemical derivatization; (3) derivatization d
chemical reaction of peptides or proteins; (4)
modi

The key for discovering new protein
biomarkers relies on quantitative determination
of protein changes in diseased and control
samples. Diseases cause pathological changes of
human tissues and organs. Proteins as the basic
functioning molecules of cells thus change
accordingly. The protein changes can be the differ-
ences in the protein concentration, co-/post-
translational modi

cation d posttranslational modi

cation of
proteins; (5) probes d small molecules that interact
or react with an active site of the folded protein;
(6) throughput d the number of samples that
can be analyzed in a single experiment; (7)
multiplexing d the intrinsic MS capability for

cation, cellular localization,
interaction, and activity ( Figure 1 ). The correlation

FIGURE 1 Quantitative proteomics for discovering protein biomarkers.