ABSTRACT
In recent years, there have been lots of progresses in the studies on red cell diseases in China, especially bone marrow failure diseases including immuno-related pancytopenia, aplastic anemia, myelodysplastic syndrome, and paroxymal nocturnal hemoglobinuria. Numerous laboratory experiments as well as clinical researches have been carried out by Chinese hematologists, which brought about much clearer pathogenesis, more rational diagnosis methods and more effective therapies for red cell diseases.
Subject(s)
Humans , Anemia, Aplastic , Diagnosis , Epidemiology , Metabolism , China , Hematologic Diseases , Diagnosis , Epidemiology , Metabolism , Hemoglobinuria, Paroxysmal , Diagnosis , Epidemiology , Metabolism , Myelodysplastic Syndromes , Diagnosis , Epidemiology , Metabolism , Pancytopenia , Diagnosis , Epidemiology , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the expressions of STAT5 phosphorylation in CD34(+)CD38(-)CD123(+) bone marrow cells of the patients with myelodysplastic syndromes (MDS), and then evaluate the level of activation of STAT5 associated with cell proliferation in MDS clone cells.</p><p><b>METHODS</b>The bone marrow mononuclear cells (BMMNC) were extracted from 36 MDS patients and 14 normal controls. The mean fluorescence intensities (MFI) of phosphorylated STAT5(P-STAT5) in CD34(+)CD38(-)CD123(+) and CD34(+)CD38(-)CD123(-)cells, with or without the stimulation of 10 U/ml EPO, were examined by flow cytometry (FCM).</p><p><b>RESULTS</b>Without stimulation, the P-STAT5 MFI in CD34(+)CD38(-)CD123(+) cells of low/high risk MDS patients was 113.71 ± 67.22/173.05 ± 102.78, which was significantly higher than that of CD34(+)CD38(-)CD123(-) cells (58.84 ± 27.51/68.99 ± 50.42, P < 0.01, P < 0.05) and the normal controls CD34(+)CD38(-)CD123(-) cells (63.06 ± 21.06, P < 0.05), there was no significant difference between the CD34(+)CD38(-)CD123(-) cells of MDS patients and the normal control CD34(+)CD38(-)CD123(-) cells; With the EPO stimulation, the P-STAT5 MFI in CD34(+)CD38(-)CD123(+) cells of low/high risk MDS patients was 144.04 ± 58.11/239.45 ± 152.05, which was significantly higher than that of CD34(+)CD38(-)CD123(-) cells (68.41 ± 25, 10/64.21 ± 23.43, P < 0.01) and the normal controls CD34(+)CD38(-)CD123(-) cells (75.21 ± 27.02, P < 0.01), there was no significant difference between the CD34(+)CD38(-)CD123(-) cells of MDS patients and the normal control CD34(+)CD38(-)CD123(-) cells; The P-STAT5 MFI in the CD34(+)CD38(-)CD123(+) cells of low/high risk MDS patients with or without EPO stimulation were 21.80/28.86, which was significantly higher than that of CD34(+)CD38(-)CD123(-) cells (7.42/5.50, P < 0.01, P < 0.05) and the normal controls CD34(+)CD38(-)CD123(-) cells (6.39, P < 0.05), there was no significant difference between the CD34(+)CD38(-)CD123(-) cells of MDS patients and the normal controls CD34(+)CD38(-)CD123(-) cells; There was no significant difference of P-STAT5 MFI with or without EPO stimulation and the increased P-STAT5 MFI between the CD34(+)CD38(-)CD123(+) cells of low and high risk MDS.</p><p><b>CONCLUSION</b>STAT5 associated with cell proliferation was activated in CD34(+)CD38(-)CD123(+) bone marrow cells in MDS, which had more significant reactions to EPO than CD34(+)CD38(-)CD123(-) cells, indicating that CD34(+)CD38(-)CD123(+) bone marrow cells might be the real malignant MDS clone cells in MDS.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Antigens, CD34 , Metabolism , Bone Marrow Cells , Cell Biology , Metabolism , Cell Proliferation , Cells, Cultured , Flow Cytometry , Myelodysplastic Syndromes , Metabolism , Pathology , Phosphorylation , STAT5 Transcription Factor , MetabolismABSTRACT
<p><b>BACKGROUND</b>Recent studies have shown that interleukin-3 receptor alpha (CD123) is highly expressed on leukemia stem cells of patients with acute myeloid leukemia, and is correlated with tumor load and poor prognosis. The expression of CD123 may also be high in patients with myelodysplastic syndrome (MDS). In this study, the expression and clinical significance of CD123 and granulocyte colony stimulating factor (G-CSF) receptor (CD114) on the bone marrow cells of patients with MDS were investigated to explore the molecular marker of the malignant clone of MDS.</p><p><b>METHODS</b>Forty-two patients with MDS, who were diagnosed in the Hematological Department of General Hospital of Tianjin Medical University from 2008 to 2009, and twelve normal controls were enrolled in this study. Fluorescence activiated cell sorter (FACS) was used to measure the expression of CD123 on CD34(+)CD38(-) cells and CD114 on CD34(+) cells of the bone marrow of these patients and controls and the clinical significance was analyzed. The expression of CD114 on CD123(+)CD34(+)CD38(-) cells was further measured to explore the molecular marker of the malignant clone in MDS.</p><p><b>RESULTS</b>MDS patients displayed significantly higher proportion of CD34(+)CD38(-)/CD34(+) ((14.03 +/- 5.27)%) than normal controls ((7.70 +/- 4.36)%, P < 0.05). The expression rate of CD123(+)CD34(+)CD38(-)/CD34(+)CD38(-) was significantly higher in MDS patients ((48.39 +/- 28.15)%) than that in normal controls ((8.75 +/- 11.71)%, P < 0.01). The expression level of CD123 was significantly correlated with the proportion of bone marrow blasts (r = 0.457, P < 0.05). The expression rate of CD114(+)CD34(+)/CD34(+) was lower in MDS patients ((33.05 +/- 21.71)%) than that in normal controls ((38.99 +/- 19.07)%) but was not statistically significant (P > 0.05). The expression of CD114 on CD123(+)CD34(+)CD38(-) cells ((34.82 +/- 29.58)%) was significantly lower than that on CD123(-)CD34(+)CD38(-) cells ((53.48 +/- 27.41)%) of MDS patients (P < 0.05).</p><p><b>CONCLUSIONS</b>MDS patients displayed higher proportion of CD34(+)CD38(-)/CD34(+) than normal controls. CD123 was highly expressed in the bone marrow of the patients with MDS, significantly correlated with the proportion of bone marrow blasts, and thus might be the marker of MDS malignant clone. CD123(+)CD34(+)CD38(-) cells exhibited lower expression of G-CSF receptors, which might partly explain why MDS clone responds worse to G-CSF in vitro and in vivo.</p>