[Abnormalities of CD34+ cells differentiation and bone marrow cell cycle in myelodysplastic syndrome].

OBJECTIVES: To detect the abnormalities of CD(34)(+) cells differentiation and bone marrow cell cycle in myelodysplastic syndrome (MDS). METHODS: Fifty newly diagnosed MDS (17 in low risk and 33 in high risk), 8 acute myeloid leukemia preceded by MDS (MDS-AML) and 25 normal controls were enrolled into this study. Their CD(34)(+)CD(38)(+), CD(34)(+)CD(38)(-) bone marrow cells and bone marrow cell cycle were measured with flow cytometry. RESULTS: The mean percentages of CD(34)(+) cells in bone marrow karyocyte of high risk [(2.29 ± 2.17)%] and MDS-AML groups [(18.69 ± 17.47)%] were significantly higher than that of control group [(0.36 ± 0.49)%, P < 0.05]. The mean percentages of CD(34)(+)CD(38)(+) cells were significantly lower in low risk, high risk and MDS-AML groups [(86.09 ± 7.79)%, (81.68 ± 11.82)% and (82.88 ± 2.60)%, respectively] than that in control group [(92.21 ± 3.85)%, P < 0.05], thus the percentages of CD(34)(+)CD(38)(-) cells were significantly higher in either MDS (low risk and high risk) or MDS-AML groups [(13.91 ± 7.79)%, (18.32 ± 11.82)% or (17.13 ± 2.60)%, respectively] than that in control group [(7.79 ± 3.85)%, P < 0.05]. The percentages of CD(34)(+)CD(38)(-) cells of MDS cases correlated directly with their International Prognostic Scoring System (IPSS) (r = 0.493, P = 0.001) and WHO Adapted Prognostic Scoring System (WPSS) (r = 0.586, P = 0.000) scores. The percentages of bone marrow mononuclear cells (BMMNCs) in G(0)/G(1) phase of in low risk, high risk and MDS-AML groups [(94.52 ± 4.32)%, (96.07 ± 3.88)% and (94.65 ± 4.55)%, respectively] were significantly higher than that in control group [(88.94 ± 7.30)%, P < 0.01], thus the percentages of BMMNCs in S and G(2)/M phase were significantly lower in either MDS (low risk and high risk) or MDS-AML groups than that in control group (P < 0.05). MDS patients with low percentages of CD(34)(+)CD(38)(-) cells presented higher therapeutic efficacy than those with high percentages of CD(34)(+)CD(38)(-) cells, while without significant differences (P > 0.05). CONCLUSIONS: There are abnormalities of differentiation of CD(34)(+) bone marrow cells and high proportion of G(0)/G(1) cells which indicates a G(1) phase arrest in MDS that might be involved in the pathogenesis of MDS. So the examination of CD(34)(+) bone marrow cells and cell cycle might be helpful for MDS diagnosis and assessment of prognosis and therapeutic effects.