Use of MDLC ‐ DIGE and LC ‐ MS / MS to identify serum biomarkers for complete remission in patients with acute myeloid leukemia

The response criteria for complete remission ( CR ) in acute myeloid leukemia ( AML ) are currently based on morphology and blood cell counts. However, these criteria are insufficient to establish a diagnosis in cases with poor quality bone marrow ( BM ) samples demonstrating a loss of cellular morphology. We investigated whether the sera of patients contained biomarkers that indicate disease response status. First, we performed multidimensional liquid chromatography‐differential gel electrophoresis ( MDLC ‐ DIGE ) to generate protein profiles of two pooled, paired serum samples from patients who had achieved CR ; one collected at diagnosis ( P re CR ) and the other collected after chemotherapy ( CR ). Then, with the biomarker candidates found, ELISA was carried out for individual P re CR and CR samples, and for other verification sets including nonremission ( NR ) patients and normal samples. We selected two proteins, complement factor H ( CFH ) and apolipoprotein H ( A po H ), with dye ( C y) ratios showing greater than 2.0‐fold differences between the pooled samples. ELISA showed that CFH and A po H are useful for distinguishing between the recovered ( CR and normal) and nonrecovered ( P re CR , P re NR , and NR ) states in AML ( p <0.001). We successfully applied a protein profiling technology of MDLC ‐ DIGE and LC ‐ MS / MS to discover two biomarkers for CR which needs further validation for a clinical setting.