OBJECTIVETo screen the molecular markers for refractory anemia with excess blasts in transformation (RAEB) in myelodysplastic syndromes (MDS) by serum proteome profiling.

METHODSThe serum protein were isolated from patients with RAEB, acute myeloid leukemia or normal subjects by 2-dimensional electrophoresis (2-DE), and the electrophoresis gels were obtained to identify the differentially reacting protein spots. The replica gels of the differentially reacting proteins were analyzed to locate the matching protein spots, which were identified by peptide mass fingerprint based on matrix-assisted laser desorption/ionization time of-flight mass spectrometry (MALDI-TOF-MS) and database searching.

RESULTSSeven differentially expressed proteins in RAEB were found by 2-DE. Of the 7 proteins, 4 were identified by MALDI-TOF-MS to have significantly differential expression in RAEB, including dipeptidyl peptidase (DPP/CD26), polymerase (DNA directed) kappa, PRO2044 and an albumin-like protein.

CONCLUSION2-DE-based serum proteome profiling helps identify serum proteomic biomarkers related to MDS. DDP/CD26 has increased expression in the serum in RAEB subtype MDS, suggesting its possible role in advanced MDS.