Fig. 1. A strategy for selecting the target HDGF–kinase pair assay. (a) Identification of HDGF by quantitative phosphoproteomics analysis of 66 year-old male patient tissues. A paired tissue analysis of the tumor tissue and the adjacent normal tissue samples were subjected to gel-assisted digestion, purification for phosphopeptides by automated pH/acid-controlled IMAC, and triplicate LC-MS/MS analysis. Bioinformatics analysis by IDEAL-Q software was used to process the quantitation result for peptide–kinase pair selection; (b) a decision tree for selecting the target peptide for synthesis. T/N = amount of phosphorylation in tumor tissue/amount of phosphorylation in normal tissue; (c) design, synthesis, and electrochemical detection of kinase-promoted phosphorylation in HDGF peptide.
