ing patient groups, showing proteins mapping to the classical immune response pathway. Proteins shown with a red thermometer symbol represent increased expression levels. (TIF) Figure S2 Representative tandem mass spectra for C- reactive protein and insert showing the peak area at the low mass/charge (m/z) region with the iTRAQ reporter ions. (TIF) Table S1 Disease characteristics of the 20 patients comprising the 4 groups of patients analysed by iTRAQ. (DOC) Serum Biomarkers for Prostate Cancer Metastasis proteins differentially expressed between the progressing and BPH group. (S3c), proteins differentially expressed between the metastasis and BPH group. (RTF) Table S4 Proteins differentially expressed between the progressing versus non-progressing group. (RTF) Acknowledgments Ms Louise Goodwin and Ms Laura Proctor are acknowledged for their assistance with serum collection. Full list of the 122 proteins identified by Author Contributions Table S2 iTRAQ. 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