Fig 1: Differential relative abundance of top serum proteins in pre-diagnostic PM cases versus controls. Box plots show relative LC-MS/MS intensities for each DEP grouped by time to diagnosis (0–2 years, 2–5 years) and matched controls. Up-regulated proteins include Complement C4A (C4; FC = 1.4, p = 0.009) and Transferrin (TF; FC = 1.4, p = 0.008). Down-regulated proteins comprise Beta-2-Microglobulin (B2M; FC = 0.7, p = 0.035), and Dermcidin (DCD; FC = 0.6, p = 0.029). Asterisks indicate nominal p < 0.05 by GLM