PROFILE OF CD150 EXPRESSION IN BONE MARROW CELLS OF PATIENTS WITH ACUTE MYELOID LEUKEMIA.

Abstract

Acute myeloid leukemia (AML) is a highly heterogeneous disease accompanied by thearrest of myeloid cell lineage differenti-ation due to accumulation of genetic abnormalities and clonal proliferation of myeloid blasts. Finding thedifferentially expressed molecules and studying their function within AML subgroups may help to improve diagnosis and prognosis with theaim of developing selected therapies for AML subsets. Theaim of this study was to reveal theprofile of CD150cell surface expression on bone marrow (BM) cells of AML patients. Thestudy was performed on samples of BM aspirates from 55patients with primarily diagnosed AML. Flow cytometry analysis was applied for theevaluation of immunophenotype profile and CD150cell surface expression on BM cells from AML patients. Four AML subtypes (M1, M2, M3and M5) were identified. TheCD150expression was found in 14 (25.5%) cases predominantly of AML M3subtype. CD150expression was detected on 43.2-83.8% of leukemia cells in AML M3. Thefrequency of CD150positive cases of non-M3AML subtypes was low: all AML M1cases were CD150-negative, while only 1 (10.0%) of 10patients with AML M2and 6 (19.4%) of 31patients with AML M5were CD150positive. Themedian percentage of CD150positive leukemia cells and theindex of mean fluorescence intensity in AML M3cases were significantly higher than in non-M3AML cases (p < 0.05). TheCD150expression was significantly associated with CD11c, CD11b, CD14, CD34, CD36, CD56and HLA-DR negative expression and CD33, CD38, CD117positive expression among theexamined cohort of patients with AML M3. High level of CD150expression is a unique feature of AML M3subtype and may serve as additional phenotype marker for theidentification of blast cells with impaired maturation at thepromyelocyte stage and thedevelopment of AML M3. At thesame time, therevealed negative association of CD150expression with poor prognostic factor CD56in AML M3subtype also allows us to suggest potential prognostic value of CD150examination in AML patients.