Expression Profile of the Progenitor Cell Markers CD34, CD38 and CD90 in Acute Myeloid Leukemia and Their Prognostic Significance

AIM: We studied the expression status and the prognostic significance of progenitor cell markers CD34, CD38, and CD90 in acute myeloid leukemia patients.METHODS: The levels of CD34, CD38, and CD90 on mononuclear cells of bone marrow were determined by flow cytometry from 56 patients, and subjected to statistical analyses for the prognostic correlation.RESULTS: CD34 was highest expressed in undifferentiated leukemia (60% positive cells) and lowest in FAB-type M3 (23% positive cells). CD38 was highly expressed in all FAB types (60-80% positive cells). CD90 was highest expressed in FAB-type M3 (73% positive cells) and lowest in M0 (9% positive cells). No differences in expression were found in different cytogenetic risk groups, in the responder's/non-responder's groups to the therapy, or in different age groups. Cut-off analyses for CD34 and CD90 showed that patients with＞43% CD34(superscript +) cells (P=0.12) and ＜64% CD90(superscript +) cells (P=0.09) had a tendency to a lower probability for relapse-free survival. After 10 months, 45% vs. 80% of patients with＞vs. ＜43% CD34(superscript +) cells were still in remission; 50% of patients with＜64% CD90(superscript +) cells had relapsed after 10 months, whereas all of the patients with＞64% CD90(superscript +) cells were in remission 24 months after first diagnosis.CONCLUSION: Progenitor cell markers like CD34, CD38, and CD90 are variably expressed in all FAB types, cytogenetic risk groups, and on cells from patients who had or had not responded to the therapy. However, amounts of detectable CD34(superscript +) and CD90(superscript +) cells could be predictive for the further course of the disease. This could contribute to differentiate leukemic from non-leukemic cells, to estimate prognosis, and to develop targeted therapies against leukemic antigens.