Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a search for a mechanism to explain the impaired growth of progenitor cells in patients with myelodysplastic syndromes (MDS), marrow CD34+ cells were purified up to 94.9% +/- 4.2% for normal individuals and 88.1% +/- 17.6% for MDS patients, using monoclonal antibodies and immunomagnetic microspheres (MDS CD34+ cells). Phenotypic subpopulations of these CD34+ cells were analyzed for CD38, HLA-DR, CD33, CD13, CD14, CD41 and CD3 plus CD19, in association with proliferative and differentiative capacities. The 15 studies performed included 12 MDS patients. Coexpression rate of CD13 significantly increased in the MDS CD34+ cell population with a value of 91.4% +/- 11.6% and ranging from 60.3% to 100%, and exceeded 99% in four studies, whereas that of normal CD34+ cells was 49.9% +/- 15.8%, ranging from 28.2% to 70.1% (P < .001). Coexpression rate of CD38, HLA-DR, CD33, CD14, and CD3 plus CD19 in MDS CD34+ cells did not significantly differ from that of normal CD34+ cells. The total number of colonies and clusters grown from 100 normal marrow CD34+ cells was 40.4 +/- 8.6, the range being from 27.2 to 50.3; this varied in MDS marrow CD34+ cells with a value of 34.0 +/- 28.7, the range being 0 to 95.9. The lineage of colonies and clusters promoted by MDS marrow CD34+ cells was predominantly committed to nonerythroid with impaired differentiation in 13 of 15 studies (87%). CD13 is first expressed during hematopoiesis by colony-forming unit granulocyte-macrophage and is absent in erythroid progenitors. Therefore, this study provides direct evidence for the lineage commitment of MDS CD34+ cells to nonerythroid with impaired differentiation and explains the mechanism of nil or low colony expression of MDS progenitor cells to erythroid lineage.
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PMID:Proliferation and differentiation of myelodysplastic CD34+ cells: phenotypic subpopulations of marrow CD34+ cells. 752 67

The experiments have been undertaken whether DNA contents could be measured using whole blood lysis method by FACScan. Cell population in the phases of G1, S and G2 + M were well analyzed, when we used 3 x 10(6) cells lysed with 0.1% Triton X-100 in 1 ml of phosphate buffered saline, staining with 30 micrograms/ml of propidium iodide (PI) within 30 min after staining with PI. We have further developed cell cycle analysis for cells bearing lineage specific antigens recognized with FITC-conjugated monoclonal antibodies using two color analysis. When we fixed cells with 50% ice-cold ethanol after staining cells with FITC-conjugated antibodies, positive population ratio in these cells have been unchanged before and after fixing for CD3, CD4, CD5, CD8. CD10, CD19, CD14, CD33, and HLA-DR, but CD7 positive cells were markedly decreased after fixing. Using this method, CD41 positive leukemia cells have 3.4% in S phase and 6.8% in G2 + M phase, while CD41 negative cells have 1.8% in S phase and 2.0% in G2 + M phase in a patient with AML: M7, resulting leukemia cells were rich in S phase and G2 + M phase. The similar results were obtained in patients with AML:M2 using CD33 antibodies. During the clinical course, the changes of the blast numbers were well-correlated with changes of S-phase proportion in the patient with AML:M2. Among 47 patients with hematological malignancies in our hospital tested here, only 2 cases with 4.3% of total patients showed to have aneuploidy in malignant cells. One is a patient with non-Hodgkin lymphoma, the other is myelodysplastic syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Analysis of DNA contents in hematological malignant cells using whole blood lysis method]. 799 13

We treated a 16-month-old girl with myelodysplastic syndrome (MDS; refractory anemia with excess of blasts subtype, RAEB by FAB classification) that developed into acute megakaryoblastic leukemia (ANLL-M7). The blast cells were positive for CD41 shown by flow cytometry and for platelet peroxidase by electron microscopy. Cytogenetically, five kinds of abnormal karyotypes were apparent at the initial visit and karyotypic progression (clonal evolution) was also evident. These karyotypes were considered to be derived from the putative original clone, 48,XX, +6, +21. The observed karyotypes were considered 50,XX, +4,add(4)(q31), +6,add(7)(p22),add(10)(q24),add(12)(q11), +20, +21, + mar[karyotype A];48,XX,add(4)(q31), +6,add(10)(q24),add(12)(q11), +21 [karyotype B];48,XX, +6,t(6;13)(p23;q14), +21 [karyotype C];51,XX, +X, t(6;13)(p23;q14), + der(6)t(6;13)(p23;q14), +21, +21, + mar [karyotype D]; and 49,XX, +X, -3,t(6;13)(p23;q14), +der(6)t(6;13)(p23;q14), -12, +21, +21, + mar [karyotype E]. It seems karyotypes B and C were derived from the putative clone; karyotype B developed into karyotype A; and karyotype C developed into karyotype E through karyotype D. After development of ANLL-M7, the cytogenetic study showed a karyotype with further karyotypic progression. The patient was treated with high-dose cytosine arabinoside (HD AraC) followed by allogeneic bone marrow transplantation. Despite intensive care, she died 3 months after the transplantation.
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PMID:Childhood myelodysplastic syndrome with clonal evolution progressing to acute megakaryoblastic leukemia (ANLL-M7). 822 7

A novel long-term cultured interleukin (IL)-3-dependent human myelodysplastic cell line, MDS92, was shown to contain several myeloid-lineage cells such as neutrophils, macrophages, eosinophils, and a small number of megakaryocyte-lineage cells. Therefore this cell line possesses at least bipotential characteristics of myeloid- and megakaryocyte-lineages. Granulocyte colony-stimulating factor clearly promoted the neutrophil alkaline phosphatase activity of MDS92 cells. To the contrary, the incidence and growth of CD41-positive cells were hardly affected by the addition of IL-6, IL-11, c-mpl ligand (thrombopoietin, TPO) or erythropoietin. TPO slightly supported the growth of CD34-positive cell fraction, but not CD41-positive cell fraction of MDS92 cells in combination with IL-3 or Steel factor. This cell line will be a useful tool for the study of MDS stem cells, but the mechanism of commitment of differentiation in MDS stem cells remains unknown.
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PMID:A novel factor-dependent human myelodysplastic cell line, MDS92, contains haemopoietic cells of several lineages. 854 20

A 46-year-old man with Werner's syndrome was admitted with epigastralgia and body weight loss. The peripheral blood findings showed anemia, thrombocytosis and eosinophilia. Bone marrow aspiration and biopsy revealed increases in eosinophils and megakaryocytes, myelodysplastic change with 6.6% myeloblast, and myelofibrosis. Chromosomal analysis revealed 46, XY, +der(1;7), -7, del(20). He was diagnosed as having myelodysplastic syndrome with myelofibrosis or essential thrombocythemia. Three months later, pancytopenia appeared with a relative increase of blasts positive for CD41 and negative for myeloperoxidase. He died of respiratory failure due to pneumonia. An autopsy revealed severe myelofibrosis with proliferation of megakaryocytes and blasts. A final diagnosis of acute megakaryoblastic leukemia was made. Werner's syndrome is rare, and it is even more unusual to have the complication of acute leukemia with der (1;7) seen in this case.
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PMID:[Werner's syndrome developing acute megakaryoblastic leukemia with der(1;7)]. 902 58

A case of a 66-year-old Japanese man developed therapy-related megakaryoblastic leukemia with pituitary involvement after chemotherapy for non-Hodgkin's lymphoma. Alkylating agents had been administered for the treatment of non-Hodgkin's lymphoma and 6 years later, megakaryoblastic leukemia with myelofibrosis and myelodysplasia developed. The blast cells expressed CD41, and immature antigens also. These findings were compatible with therapy-related megakaryoblastic leukemia. An autopsy revealed blast-cell infiltration into multiple organs including the posterior pituitary lobe. Therapy-related megakaryoblastic leukemia is very rare, and pituitary involvement may be associated with immaturity of blast cells.
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PMID:Therapy-related megakaryoblastic leukemia with pituitary involvement following treatment for non-Hodgkin's lymphoma. 1056 55

It has previously been shown that patients with aplastic anemia (AA) have a stem cell defect both of proliferation and differentiation. This has been shown by long-term bone marrow (BM) culture, long-term initiating cell assays, and committed progenitor assays. We present, for the first time, data on megakaryocyte (Mk) colony formation from purified BM CD34(+) cells from patients with AA. The results are compared with those from normal controls and from patients with paroxysmal nocturnal hemoglobinuria (PNH) and the myelodysplastic syndromes (MDSs). Those treated for AA had previously received immunosuppression (antithymocyte globulin and/or cyclosporin). No patients had received bone marrow transplantation. A total of 13 AA patients (five untreated, eight treated), six PNH, six MDS, and 13 normal donors were studied. BM CD34(+) cells were purified by indirect labeling and then cultured in a collagen-based Mk assay kit (MegaCult-C, StemCell Technologies). The cultures were fixed on day 12, and the Mk colonies were identified by the alkaline phosphatase anti-alkaline phosphatase technique using the monoclonal antibody CD41 (GP IIb/IIIa). The slides were scored for Mk colony-forming units (CFU-Mks) (3-20 and >20 cells), Mk burst-forming units (BFU-Mks) (>50 cells), and mixed colonies. The results show that total Mk colony formation in AA was significantly lower than in normal donors (p<0.0001), both in untreated patients/nonresponders to treatment (p = 0.0001) and in complete/partial responders (p<0.002). There was no significant difference in Mk colony formation in treated and untreated patients (p = 0.05). Patients with AA had a lower total colony formation than PNH patients (p = 0.0002). PNH patients exhibited lower colony formation than normal controls (p = 0.03), as shown by MDS patients, although the considerable number of variables resulted in a lack of statistically significant difference from normal controls (p = 0.2). We have now shown that Mk colony formation from purified BM CD34(+) cells is significantly reduced, supporting previous evidence that AA results from a stem cell defect.
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PMID:In vitro proliferation and differentiation of megakaryocytic progenitors in patients with aplastic anemia, paroxysmal nocturnal hemoglobinuria, and the myelodysplastic syndromes. 1107 31

In order to observe the proliferative and apoptotic situation of megakaryocytes in patients with myelodysplastic syndromes (MDS). CD41 immunoenzyme labeling (alkaline phosphatase anti-alkaline phosphatase APAAP)/DNA in situ end labelling (ISEL) double stained techniques was used onto plastic cold embedded bone marrow sections in 29 MDS patients to analyse the proliferative and apoptostic characterization of megakaryocytic line with 14 cases of iron deficient diseases (IDA) as control. The results showed that the mean CD41 positive cell number in MDS group was (26.23 +/- 8.18) /mm(2) with a count of (15.64 +/- 7.11) /mm(2) in control group (p < 0.05). The small-micro megakaryocytes in MDS is much higher than that in IDA group (P<0.01). There was a positive co-relation between total megakaryocytes and small-micro megakaryocytes count in MDS (r = 0.702, p<0.01). Some megakaryocytes distributed abnormally around trabecula and formed small or large clusters. Apoptotic megakaryocytes in MDS occupied 4.40% and 9.32% of all CD14 positive cells and all apoptotic cells respectively (p > 0.5 comparing with control). Apoptosis in megakargocytic line occurred only in small-micro megakaryocytes and showed positive co-relation to the number of micro-megakaryocytes. Some apoptotic cell with morphologic characters of megakaryocytes expressed no CD41. It is concluded that overproliferation of megakaryocytes exists in MDS. Apoptosis occurring in micro-megakaryocytes may be a kind of physiological response to abnormal megakaryopoicsis in MDS. No obvious increased apoptosis of megakaryocytes in MDS was found perhaps due to lack of surface antigens CD41 in some later stages of apoptotic cell.
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PMID:[Study about proliferation and apoptosis of megakaryocytes in patients with myelodysplastic syndromes]. 1251 35

The study was aimed to observe morphological characteristics and hematopoiesis function of bone marrow megakaryocyte in children patients with myelodysplastic syndrome (MDS), and analyse the cause and mechanism of thrombocytopenia. CD41 McAb immunohistochemical technique was used to detect micromegakaryocytes of bone marrow smear. Plasma clot culture and CD41 McAb immunohistochemical technique were used for the MK-colony forming assay. The colony formations of CFU-MK and BFU-MK were measured. The results showed that there was no significant difference of CFU-MK colony formation rate between groups of MDS and control. But, in 62.5% of children patients the colony formation rate of CFU-MK decreased, in 25% increased, and in 12.5% was normal while BFU-MK formation rate decreased in MDS group significantly. The number of micromegakaryocyte and the positive rate of type I lymphoid micromegakaryocyte were significantly higher than those of the control group. In conclusion, there may be two kinds of megakaryocyte clones in bone marrow of children patients with MDS. One is supposed to be pathologic and potentially malignant micromegakaryocytes, the another may be the normal megakaryocytic precursors. The thrombocytopenia in MDS patients induced by increase of pathologic MK leads to abnormal development and maturation of MK in bone marrow.
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PMID:[Study on bone marrow megakaryocytes in children patients with myelodysplastic syndrome]. 1498 74

In order to investigate simultaneously the megakaryocytopoiesis and apoptotic characteristics in bone marrow in patients with myelodysplastic syndromes (MDS), we used CD41 immunoenzyme (alkaline phosphatase anti-alkaline phosphatase) and DNA in situ end-labeling techniques on plastic embedded bone marrow biopsy sections of 29 MDS patients. Fourteen patients with iron deficiency anemia served as controls. The results showed that CD41-positive cells in MDS marrow numbered 26.2 +/- 18.2/mm2 (mean +/- standard deviation) compared with 15.6 +/- 7.1/mm2 in controls (P < 0.05). Numbers of cells with the morphology of micro-megakaryocytes in MDS marrow were significantly higher than in controls (P < 0.01). Furthermore, megakaryocytes in MDS marrow were frequently distributed along trabeculae (in 27 cases) and formed clusters (in 25 cases). Apoptotic megakaryocytes in MDS marrow accounted for just 4.4 and 9.3% of all CD41-positive cells and all apoptotic cells, respectively (P > 0.05 compared with controls), but apoptosis occurred only in micro-megakaryocytes. Based on these observations, we conclude that megakaryocytosis and dysmegakaryocytosis are the features of dyshematopoiesis in MDS marrow. Decreased thrombocyte production and thrombocyte release coming from increased dys(micro)megakaryocytes and abnormally located megakaryocytes perhaps play a more important role in peripheral thrombocytopenia than megakaryocytic apoptosis itself. Apoptosis of micro-megakaryocytes may be a protective biological mechanism to remove useless megakaryocytes.
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PMID:Megakaryocytopoiesis and apoptosis in patients with myelodysplastic syndromes. 1562 28


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