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)

Refractory anemia (RA) in myelodysplastic syndrome (MDS) without prominent dysplasia closely resemble the mild type of aplastic anemia (AA) in their hematological features. This sometimes makes it difficult to distinguish clearly between the two diseases. Using the multi-color flow cytometric technique, we compared cell surface antigen expression patterns on bone marrow hematopoietic progenitor cells which were isolated as a CD34 positive- CD45 dull positive with low side scatter intensity (CD34(+)CD45(dull+)SSC(low)) population in flow cytogram between RA (n=12) and AA (n=11). The antigens analyzed in CD34(+)CD45(dull+)SSC(low) mononuclear cells were: CD38 and CD71 for cell growth-related antigens, CD 33 and CD13 for myeloid and monocytoid lineage-associated antigens, CD7 and CD19 for lymphoid lineage, and CD14 for a monocytic lineage specific antigen. The percentages of CD34(+)CD45(dull+)SSC(low) cells in bone marrow non-erythroid mononuclear cells, and the expression frequencies of CD38, CD71, CD33 and CD13 antigens in CD34(+)CD45(dull+)SSC(low) progenitors were all significantly decreased in AA compared to normal bone marrows (n=7) (P<0.005). In contrast, in RA bone marrows the percentages of CD34(+)CD45(dull+)SSC(low) cells showed wide distribution and the cell surface antigen expression patterns varied among each case: some cases showed low frequencies of CD38 and CD71 expression as well as AA, whereas the others showed high expression frequency of specific antigen(s) which may reflect the clonal expansion of an abnormal clone in bone marrow. An MDS patient who had progressed from RA to RAEB showed further projecting pattern of expression of CD38 and CD33 in CD34(+)CD45(dull+)SSC(low) population in accordance with the disease progression. These data suggest that analysis of cell surface antigen expression patterns of CD34(+)CD45(dull+)SSC(low) progenitor cells by multi-color flow cytometry appears to be a useful method for qualitative and quantitative assessment of marrow progenitor states in AA and RA, therefore this method could be helpful for early detection of clonal evolution in MDS.
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PMID:Comparative multi-color flow cytometric analysis of cell surface antigens in bone marrow hematopoietic progenitors between refractory anemia and aplastic anemia. 1086 34

Circulating serum transferrin receptor level was measured using mouse monoclonal antibody against transferrin receptor (Orion Diagnostica, Finland) in 126 patients with various disorders of erythropoiesis and the results were compared to those obtained form control group consisted of 30 healthy volunteers with normal iron stores. Serum transferrin receptor level was significantly elevated in patients with iron deficiency and in all patients with hyperplastic erythropoiesis (hereditary spherocytosis, immune hemolytic anemia, beta thalassemia, myelodysplasia). Measurement of circulating serum transferrin receptor level was a sensitive indicator of iron depletion as well as a helpful parameter in differential diagnosis between iron deficiency and anemia of chronic disease where circulating transferrin receptor level was not elevated. Index transferrin receptor/ferritin calculated as a ratio of circulating serum transferrin receptor level to log serum ferritin level was a more sensitive parameter than measurement of serum transferrin receptor not only for determination of patients with anemia of chronic disease, but also for discrimination of patients with elevated serum transferrin receptor level due to true iron deficiency from those with high serum transferrin receptor level caused by relative iron deficiency in hyperplastic erythropoiesis.
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PMID:[Clinical importance of determining levels of circulating transferrin receptors in blood]. 1104 46

Iron is essential for cell proliferation, heme synthesis, and a variety of cellular metabolic processes. In most cells, transferrin receptor-mediated endocytosis is a major pathway for cellular iron uptake. Recently, transferrin receptor 2 (TfR2), another receptor for transferrin, was cloned. High levels of expression of TfR2 messenger RNA (mRNA) occur in the liver, as well as in HepG2 (a hepatoma cell line) and K562 (an erythroid leukemia cell line). In this study, TfR2 mRNA expression was analyzed in hematological cell lines, normal erythroid cells at various stages of differentiation, and leukemia and preleukemia cells. High levels of TfR2 expression occurred in all of the erythroid cell lines that were examined. Erythroid-specific expression of TfR2 protein in bone marrow cells was confirmed by immunohistochemical staining. Expression of TfR2 mRNA was high in normal CD34(+) erythroid precursor cells, and levels decreased during erythroid differentiation in vitro. Levels of expression of TfR2-alpha mRNA were significantly higher in erythroleukemia (M6) marrow samples than in nonmalignant control marrow samples. In addition, relatively higher levels of TfR2-alpha mRNA expression occurred in some samples of myelodysplastic syndrome that had erythroid hyperplasia in bone marrow, acute myelogenous leukemia M1, M2, and chronic myelogenous leukemia. Expression profiles of normal members of the erythroid lineage suggest that TfR2-alpha may be a useful marker of early erythroid precursor cells. The clinical significance of TfR2-alpha expression in leukemia cells remains to be determined.
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PMID:Expression of transferrin receptor 2 in normal and neoplastic hematopoietic cells. 1167 42

Myelodysplastic syndromes (MDSs) are heterogeneous diseases of bone marrow (BM) cell precursors for which immunophenotypic characterization is still considered irrelevant despite the accuracy and sensitivity of flow cytometry techniques. The aim of this study was to determine whether immunophenotypic abnormalities could be defined in MDSs and could correlate with the French-American-British classification and cytogenetics. Analysis was performed on 275 BM samples (207 MDS patients, 68 controls) and 25 control blood samples. Immunophenotyping was based on a primary gating of blast cells, monocytes, and granulocytes according to CD45 antigen expression and side scatter light diffraction. Immunophenotypic hierarchical clustering was performed to analyze the results. The data obtained show that (1) immunophenotypic clustering partly discriminates patients with refractory anemia with excess blasts/refractory anemia with excess blasts in transformation (RAEB/RAEB-T), chronic myelomonocytic leukemia (CMML), and refractory anemia/refractory anemia with ring sideroblasts (RA/RARS) for CD45(lo) blast cells and patients with RA/CMML, RARS, and RAEB/RAEB-T for CD45(hi)/side scatter(hi) (SS(hi)) granulocytes; (2) the most discriminating markers were CD16, CD34, CD36, CD38, CD71, and HLA-DR for blast cells and CD11b, CD13, CD33, CD36, CD38, CD71, and HLA-DR for CD45(hi)/SS(hi) granulocytes; (3) clusters related to CD34 expression were associated with high levels of blast cells on BM smear; (4) clusters related to high levels of CD36 expression on CD45(lo) blast cells and CD45(hi)/SS(hi) granulocytes were associated with a poor International Prognosis Scoring System score; and (5) high levels of CD71 expression on CD45(hi)/SS(hi) granulocytes were associated with the RARS category. These results show a close relationship between immunophenotypic abnormalities and BM dysplasia and suggest that flow cytometry could be a future tool for the characterization of MDSs.
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PMID:Immunophenotypic clustering of myelodysplastic syndromes. 1223 42

The phenotypes of the bone marrow cells in various subtypes of myelodysplastic syndromes (MDS) and its clinical implication were explored. The antigen expression of a panel of antigens expressed in marrow cells from 30 patients with subtypes of MDS was assayed by alkaline phosphatase anti-alkaline phosphatase method. The results showed that the expression of myeloid antigens appeared abnormality, CD13 and CD33, found on granulocyte and macrophage precursors, increased, and CD15 decreased. There were no significant changes for monocytic antigen CD14 and lymphoid antigens CD7 and CD10. CD34 was increased in RAEB/RAEB-t and was not increased in RA/RAS patients. CD71, expressed by erythroblast and proliferative cells, was higher in all subtypes of MDS than that in control group. It is suggested that the bone marrow cells from MDS patients showed abnormality of more than two series of immunophenotypes, detection of immunophenotype in MDS cells might be contributed to the diagnosis and predicting prognosis.
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PMID:[Study on the immunophenotypes of bone marrow cells from patients with myelodysplastic syndromes and its clinical implications]. 1251 25

Serum soluble transferrin receptor (sTfR) has been reported to be higher in patients with iron deficiency or with elevated erythropoiesis. In the present study, serum sTfR was measured in various anemic diseases and their clinical significance was examined in a multi-institutional joint study. Serum sTfRs in patients with the following anemic diseases were markedly higher than those in normal healthy adults: non-treated iron deficiency anemia (IDA) (9.13 +/- 7.04 mg/l, n = 52, p < 0.0001), anemia of chronic disorders (ACD) (3.45 +/- 1.38 mg/l, n = 20, p < 0.0001), hemolytic anemia (HA) (5.57 +/- 3.26 mg/l, n = 17, p < 0.0001), and myelodysplastic syndrome (MDS) (4.03 +/- 2.83 mg/l, n = 20, p < 0.0001). There were significant differences between IDA and ACD (p < 0.0001), between aplastic anemia (AA) (1.58 +/- 1.26 mg/l, n = 16) and MDS (p < 0.001), and between AA and MDS with refractory anemia (MDS-RA) (4.16 +/- 3.40 mg/l, n = 9) (p < 0.02). In patients with chronic renal failure (CRF), serum sTfR levels and serum sTfR/log serum ferritin ratios (sTfR/F index) were compared in the two classified groups according to Muirhead's criteria, as IDA and non-IDA groups with or without recombinant human erythropoietin (rHuEPO) treatment. Significantly high levels of both serum sTfR (p < 0.0001) and the sTfR/F index (p < 0.0001) were observed in IDA without rHuEPO treatment. Especially in CRF with rHuEPO treatment, the sTfR/F index showed marked elevation in the IDA group (p < 0.0001) compared with serum sTfR (p < 0.001), indicating more diagnostic efficacy of the sTfR/F index for CRF with IDA. In conclusion, the serum sTfR concentration is a useful diagnostic tool for discrimination between IDA and ACD, and between AA and MDS-RA, and for the detection of iron deficiency in CRF patients in the Japanese population.
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PMID:Diagnostic significance of serum soluble transferrin receptors in various anemic diseases: the first multi-institutional joint study in Japan. 1261 83

In the past seven years numerous genes that influence iron homeostasis have been discovered. Dr. Beutler provides a brief overview of these genes, genes that encode HFE, DMT-1, ferroportin, transferrin receptor 2, hephaestin, and hepcidin to lay the groundwork for a discussion of the various clinical forms of iron storage disease and how they differ from one another. In Section I, Dr. Beutler also discusses the types of hemochromatosis that exist as acquired and as hereditary forms. Acquired hemochromatosis occurs in patients with marrow failure, particularly when there is active ineffective erythropoiesis. Hereditary hemochromatosis is most commonly due to mutations in the HLA-linked HFE gene, and hemochromatosis clinically indistinguishable from HFE hemochromatosis is the consequence of mutations in three transferrin receptor-2 gene. A more severe, juvenile form of iron storage disease results from mutations of the gene encoding hepcidin or of a not-yet-identified gene on chromosome 1q. Autosomal dominant iron storage disease is a consequence of ferroportin mutations, and a polymorphism in the ferroportin gene appears to be involved in the African iron overload syndrome. Evidence regarding the biochemical and clinical penetrance of hemochromatosis due to mutations of the HFE gene is rapidly accumulating. These studies, emanating from several centers in Europe and the United States, all agree that the penetrance of hemochromatosis is much lower than had previously been thought. Probably only 1% of homozygotes develop clinical findings. The implications of these new findings for the management of hemochromatosis will be discussed. In Section II, Dr. Victor Hoffbrand discusses the management of iron storage disease by chelation therapy, treatment that is usually reserved for patients with secondary hemochromatosis such as occurs in the thalassemias and in patients with transfusion requirements due to myelodysplasia and other marrow failure states. Tissue iron can be estimated by determining serum ferritin levels, measuring liver iron, and by measuring cardiac iron using the MRI-T2* technique. The standard form of chelation therapy is the slow intravenous or subcutaneous infusion of desferoxamine. An orally active bidentate iron chelator, deferiprone, is now licensed in 25 countries for treatment of patients with thalassemia major. Possibly because of the ability of this compound to cross membranes, it appears to have superior cardioprotective properties. Agranulocytosis is the most serious complication of deferiprone therapy and occurs in about 1% of treated patients. Deferiprone and desferoxamine can be given together or on alternating schedules. A new orally active chelating agent ICL 670 seems promising in early clinical studies. In Section III, Dr. James Cook discusses the most common disorder of iron homeostasis, iron deficiency. He will compare some of the standard methods for identifying iron deficiency, the hemoglobin level, transferrin saturation, and mean corpuscular hemoglobin and compare these with some of the newer methods that have been introduced, specifically the percentage of hypochromic erythrocytes and reticulocyte hemoglobin content. The measurement of storage iron is achieved by measuring serum ferritin levels. The soluble transferrin receptor is a truncated form of the cellular transferrin receptor and the possible value of this measurement in the diagnosis of iron deficiency will be discussed. Until recently iron dextran was the only parental iron preparation available in the US. Sodium ferric gluconate, which has been used extensively in Europe for many years, is now available in the United States. It seems to have a distinct advantage over iron dextran in that anaphylactic reactions are much less common with the latter preparation.
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PMID:Iron deficiency and overload. 1463 76

The purpose of this study was to develop a flow cytometric approach to the evaluation of marrow dysplasia in myelodysplastic syndromes (MDS). We first studied a cohort of 103 MDS patients as well as 46 pathological and healthy controls. Flow cytometry data were expressed as percentage of positive cells. Analysis of erythroid cells showed higher proportions of immature cells (P < 0.001) and decreased levels of CD71 expression on nucleated red cells (P = 0.02) in MDS. Analysis of myeloid cells showed lower proportions of CD10+ and higher proportions of CD56+ granulocytes (P < 0.001), and increased ratios of immature to mature cells (P = 0.007). Since no single immunophenotype could accurately differentiate MDS from other conditions, we used discriminant analysis for generating erythroid and myeloid classification functions using combinations of immunophenotypic parameters. These functions were prospectively validated in a testing cohort of 69 MDS patients and 46 pathological controls. A diagnosis of MDS was obtained in 60/69 cases (87%). No false-positive results were noticed among controls. Significant correlations between values of these functions and both degree of morphological dysplasia and the International Prognostic Scoring System were found. These findings indicate that flow cytometry evaluation of marrow dysplasia is feasible and may be useful in the work-up of individual MDS patients.
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PMID:Flow cytometry evaluation of erythroid and myeloid dysplasia in patients with myelodysplastic syndrome. 1578 68

To study the effect of interleukin-15 (IL-15) on the proliferation, differentiation and apoptosis of MDS CD34(+) cells, CD34(+) cells of high enrichment were separated by MACS system, and cultured in liquid media with different concentration of IL-15 in treated group and without IL-15 in the control group. Apoptosis of hematopoietic precursors was assayed by propidium iodine staining and cell by FCM, and the other MDS CD34(+) cells were stained by cytochemical staining after culture. The results showed that after culture with IL-15 the proliferation and differentiation of MDS CD34(+) cells were obviously promoted. It was found the every lineage of mature cells developed, the expressions of cell surface antigens CD71, CD33 and CD19 all increased in the MDS CD34(+) cell treated with IL-15. It is suggested that IL-15 stimulates the proliferation and differentiation of MDS CD34(+) cells, and partly shows anti-apoptosis effects which may be applicable to the therapy MDS.
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PMID:[Effect of IL-15 on the proliferation, differentiation and anti-apoptosis of CD34+ cells in patients with MDS]. 1612 46

Erythroid dysplasia is the pathologic hallmark of myelodysplastic syndromes (MDS). To develop a quantitative flow-cytometry approach to its evaluation, we analyzed the expression of CD71, CD105, cytosolic H-ferritin (HF), cytosolic L-ferritin (LF) and mitochondrial ferritin (MtF) in erythroblasts from 104 MDS patients, 69 pathologic control patients and 19 healthy subjects. Six-parameter, 4-color flow cytometry was employed, and data were expressed as mean fluorescence intensity. Compared with pathologic and healthy controls, MDS patients had higher expression of HF (P < 0.001) and CD105 (P < 0.001), and lower expression of CD71 (P < 0.001). MtF was specifically detected in MDS with ringed sideroblasts, and there was a close relationship between its expression and Prussian blue staining (r = 0.89, P < 0.001). In vitro cultures of myelodysplastic hematopoietic progenitors showed that both HF and MtF were expressed at a very early stage of erythroid differentiation, and that MtF expression is specifically related to mitochondrial iron loading. A classification function based on expression levels of HF, CD71 and CD105 allowed us to correctly classify > 95% of MDS patients. This flow-cytometry approach provides an accurate quantitative evaluation of erythroid dysplasia and allows a reliable diagnosis of sideroblastic anemia, and may therefore be a useful tool in the work-up of patients with MDS.
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PMID:Flow cytometry evaluation of erythroid dysplasia in patients with myelodysplastic syndrome. 1649 94


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