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)

We conducted a Phase I-II trial of recombinant human erythropoietin-beta (rhEPO) in patients with myelodysplastic syndrome (MDS). Patients with anemia and pathologically confirmed MDS were eligible for the study. Treatment consisted of rhEPO by subcutaneous injection thrice weekly for 6 weeks at one of three dose levels (100 U/kg (three patients), 200 U/kg (three patients) and 400 U/kg (14 patients)). Ferrous sulfate (325 mg po tid) was also administered if the transferrin saturation was below 30% (two patients). Patients were monitored with weekly CBC, white cell differential, and reticulocyte counts. Bone marrow examinations were performed at the conclusion of the treatment period and after a 2 week washout period. Patients who responded to therapy were continued on rhEPO at the same dose for 6 additional months. Response criteria included: 50% reduction in transfusion requirements compared with the 6 week pre-study period; doubling of reticulocyte count that was maintained on two determinations at least 1 week apart; or an increase in hemoglobin by at least 1.2 gm/dl without transfusions. Pre-treatment factors potentially predictive of response were analyzed by univariate analysis and in a multivariate fashion by classification and regression trees. Seven of the twenty patients sustained an untransfused rise in serum hemoglobin > or = 1.2 gm/dl. Four of the sixteen patients (including three of seven patients experiencing a rise in serum hemoglobin) who were transfusion-dependent prior to the study achieved a reduction or elimination of their transfusion requirements. Five of thirteen patients who received rhEPO during the extension phase had a continued response. A low baseline erythropoietin level (< 50 mU/ml) was the best predictor of hemoglobin response when controlling for other variables. rhEPO has a role in the treatment of certain patients with MDS, particularly in those whose endogenous serum erythropoietin levels are not markedly elevated.
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PMID:Therapy with recombinant human erythropoietin in patients with myelodysplastic syndromes. 793 35

Erythropoietin, alone or in combination with colony-stimulating factors, is a promising agent in the treatment of patients with cancer-related 'anemia of chronic disorders', chemo/radiotherapy-induced anemia, or anemia due to myelodysplastic or myeloproliferative syndromes. In the first two groups, at least half of the patients can be expected to respond to erythropoietin alone, with an average response delay of about 4 weeks and maximal responses at weekly doses of approximately 1000 U/kg. In myelodysplastic syndromes, only 10-20% of patients respond to conventional doses of erythropoietin, but doses exceeding 1000 U/kg weekly in combination with granulocyte colony-stimulating factor yield response rates of about 40%. Although these results show that hematopoietic growth factors can be used successfully to treat cancer-related anemias, economic constraints preclude their use at the present time.
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PMID:Hematopoietic growth factors and the treatment of tumor-associated anemias. 794 10

To determine the efficacy of recombinant human erythropoietin at pharmacological doses in myelodysplastic syndromes (MDS) without excess of blasts, 20 patients with refractory anemias (RA) or refractory anemias with ring sideroblasts (RARS) were treated in an open study with escalating doses from 40 U/kg to 300 U/kg three times a week subcutaneously during a period of 3 months. Maintenance therapy at the lowest effective dose was continued in responders. A dose response of CFU-E and BFU-E to Epo was analysed at the entry. Bone marrow examination with an in vitro study of hematopoietic progenitors was performed before and after the first three months. Seven of 20 patients responded: a total recovery was observed in 3 patients; one became transfusion independent and a reduction of 50% of the transfusion requirement was achieved in 3 others. 3 patients are still receiving treatment for 2, 3 and 4 years. No significant correlation was found between the in vitro and clinical response. A non parametric analysis of responders and non responders emphasised the importance of a long delay between the diagnosis and the treatment, (p = 0.024) and an endogenous Epo level less than 100 mU/ml (p = 0.025) in order to predict the efficacy of rhEpo. This study offers evidence that patients with refractory anemias without excess of blasts in the bone marrow respond to rhEpo at pharmacological doses. Larger studies are required in order to define the patients who may respond and to elucidate the mechanism of the positive effect of rhEpo.
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PMID:Efficacy of recombinant human erythropoietin in the treatment of refractory anemias without excess of blasts in myelodysplastic syndromes. 816 62

The purpose of this study was to improve erythropoiesis in patients with anemia due to myelodysplastic syndromes (MDS). We treated 13 patients first with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for 6 weeks, then with recombinant human erythropoietin (rhEpo) and rhGM-CSF for the next 12 weeks. Five patients had refractory anemia (RA), 3 refractory anemia with ringed sideroblasts (RAS), and 5 refractory anemia with excess of blasts (RAEB). Ten patients were transfusion-dependent at the time of inclusion. Eleven patients completed this phase II study. Five responded with an increase in hemoglobin level (3 patients) or a reduction in transfusion requirement (2 patients). We registered no response in the remaining 6 patients during treatment. Patients responding to combined treatment had relatively low concentrations of plasma Epo and plasma ferritin before treatment with rhEpo and a normal karyotype throughout the study. Long-term bone marrow cultures did not predict the response. Still, responders seemed to have a higher number of colony-forming progenitors than nonresponders. In conclusion, combined therapy with rhGM-CSF and rhEpo may stimulate hematopoiesis and correct or improve anemia in some patients with MDS.
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PMID:Recombinant human granulocyte-macrophage colony-stimulating factor plus recombinant human erythropoietin may improve anemia in selected patients with myelodysplastic syndromes. 823 92

In the past anabolic steroids were the first-choice treatment for pancytopenic disorders that were often poorly classified. They are now superseded by other more recently developed methods of treatment--for example bone marrow transplantation and immunosuppression. This contrasts to the authors' experience, and to that of many other haematologists, who have noted anabolic steroid-induced responses in patients who were unsuitable for or unresponsive to the new treatments. Anabolic steroids did not, however, demonstrate an obvious effect in recent controlled trials involving patients with aplastic anaemia. Their use with immunosuppressive treatment is currently under investigation. Although anabolic steroids rarely reverse the course of anaemia in a myelodysplastic syndrome, even a slight haemopoietic improvement is desirable. Children with Fanconi's anaemia may benefit from a reduced transfusion requirement. Uraemic patients may experience significant side effects on standard erythropoietin (epo) treatment. There have been no controlled trials comparing epo versus anabolic steroids or epo versus epo in conjunction with anabolic steroids. Data from uncontrolled studies indicate a better response to anabolic steroids in children and females than in men. In spite of the fact that anabolic steroids have been used for almost 30 years, they should be carefully re-evaluated in scientifically controlled trials to test their efficacy and to compare them with the new treatments. Such trials, however, are impeded by the limited knowledge available with regard to pharmacological parameters and optimal treatment schedules.
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PMID:Anabolic steroids and blood cell production. 825 51

Recombinant human erythropoietin (rhEPO) was administered subcutaneously to 13 anemic (Hb < 10 g/dl) patients with myelodysplasia (MDS). rhEPO was given 3 times a week at doses of 75-250 U/kg body weight, over a maximum period of 24 weeks. Five patients (38%) showed a response to rhEPO treatment. rhEPO was well tolerated and without relevant side effects throughout the study. All responding patients had low but detectable pretreatment circulating erythroid progenitor cells (BFU-E) and the response to rhEPO was associated with a significant increase in BFU-E (p < 0.01); concentrations of serum transferrin receptor (TfR) also consistently rose in all responding patients. Baseline erythropoietin (EPO) concentrations did not significantly differ between responders and nonresponders, although 4 out of the 5 responders had relatively low levels of EPO. In conclusion, subcutaneous rhEPO administration appears to be an effective treatment of anemia in a substantial subset of patients with MDS. Relatively low baseline EPO concentrations, detectable pretreatment circulating BFU-E and an early increase in the serum concentrations of TfR seem to be criteria for predicting response to rhEPO in patients with MDS.
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PMID:Subcutaneous recombinant human erythropoietin for the treatment of anemia in myelodysplastic syndromes. 828 18

In a dose titration study we tested the efficacy and tolerance of recombinant human erythropoietin (rhEPO) in 10 patients with myelodysplasia (MDS) and 2 patients with idiopathic myelofibrosis. Patients with a haemoglobin level < 100 g/l were treated as out-patients for 12 weeks with daily doses ranging from 30 U/kg body weight (BW) up to 240 U/kg BW in non-responders. Of the 10 patients with MDS, 6 were suffering from refractory anaemia with sideroblasts (RAS) and 4 from refractory anaemia with an excess of blasts. The median age was 73 years (range 41-81). Two patients with RAS responded with a rise in haemoglobin concentration to > 130 g/l. They had not been transfusion-dependent prior to treatment. Both patients had relatively low serum concentrations of immunoreactive EPO. There was neither a rise in haemoglobin nor a reduction in transfusion dependence in any of the other patients. It may be concluded that rhEPO is possibly effective in a subgroup of MDS patients where the disease is less advanced. None of the transfusion-dependent patients benefited.
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PMID:Recombinant human erythropoietin in patients with myelodysplastic syndrome and myelofibrosis. 828 18

The erythroid abnormality in patients with myelodysplasia (MDS) is multifactorial, with ineffective erythropoiesis and poor in vitro progenitor response to erythropoietin (EPO). Serum EPO concentration is variable among patients for a given haemoglobin concentration. We studied 19 non-transfusion-dependent patients with MDS, and 13 healthy elderly control subjects in an attempt to define the factors governing variability in serum EPO and to further characterise the anaemia of MDS. Serum EPO concentration was appropriate for the degree of anaemia in 15/19 MDS patients, and was positively related to mean cell volume (MCV), mean cell haemoglobin (MCH), and percentage highly fluorescent reticulocytes (% HFR), but not to absolute or percentage reticulocyte count. Although the observed/predicted ratio for serum transferrin receptor (TfR) concentration was low in 12 of 19 MDS subjects, no relationship to haemoglobin concentration, reticulocytes or serum EPO was seen. Serum TfR was positively correlated with WBC and platelet counts. Serum TfR was higher in patients with sideroblastic anaemia than refractory anaemia. Standardized in vivo p50 was positively correlated to red cell 2,3 diphosphoglycerate concentration, although this was not the only factor influencing the oxygen dissociation curve. We conclude that effective erythroid output responsive to endogenous EPO drive in MDS is positively related to MCV, MCH and % HFR. Serum TfR may not represent effective output as precisely as % HFR, but may be proportional to total marrow erythropoietic activity.
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PMID:Estimation of effective and total erythropoiesis in myelodysplasia using serum transferrin receptor and erythropoietin concentrations, with automated reticulocyte parameters. 828 79

Inappropriate expression of the Evi-1 zinc-finger gene in hematopoietic cells has been associated with acute myelogenous leukemia and myelodysplastic syndromes in murine models and in humans. Consistent with this, previous studies have shown that aberrant expression of the Evi-1 gene in a myeloid progenitor cell line blocks granulocytic differentiation. Here we demonstrate that the aberrant expression of the Evi-1 gene impairs the normal response of erythroid cells or bone-marrow progenitors to erythropoietin. Erythroid differentiation has been shown to require the GATA-1 transcription factor that binds to a sequence contained within the consensus binding sequence identified for Evi-1. In the studies presented here we also show that Evi-1 can repress GATA-1-dependent transactivation in transient chloramphenicol acetyltransferase assays. Together the data support the hypothesis that inappropriate expression of the Evi-1 gene blocks erythropoiesis by repressing the transcription of a subset of GATA-1 target genes.
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PMID:Loss of erythropoietin responsiveness in erythroid progenitors due to expression of the Evi-1 myeloid-transforming gene. 834 54

The effect of human recombinant erythropoietin (rhEPO) was investigated in 29 anemic patients with myelodysplastic syndromes (MDS). A rhEPO dosage of 150 U/kg was administered subcutaneously three times weekly for a minimum of 6 weeks. Seven out of 27 evaluable patients (26%) had an effective clinical response to therapy by increasing hemoglobin concentrations by more than 15 g/l (reaching at least 105 g/l) or by eliminating transfusion requirements. Six out of the seven patients responded within four weeks. Three of the responders successfully continued rhEPO treatment 15 months or more. To determine whether it may be possible to predict response to rhEPO, various clinical parameters were examined. Responders were found to be significantly different from non-responders in five aspects: They had less elevated baseline serum EPO levels (92 +/- 33 versus 515 +/- 108 U/l, mean +/- SEM; p = 0.023) and were more often transfusion-independent (71% versus 20% of non-responders; p = 0.022). Furthermore, responders were more often females (71% versus 40% in the non-responding group; p = 0.025), of subtype RA rather than RAEB (four patients and one patient, respectively, compared to seven and nine patients in the non-responding group; p = 0.025), and they predominantly displayed normal karyotypes or a 5q- aberration (86% versus 47%; p = 0.005). We conclude, that rhEPO treatment can reduce anemia in MDS and that certain pre-treatment clinical parameters may be used to predict response.
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PMID:Prediction of response to treatment with human recombinant erythropoietin in myelodysplastic syndromes. 837 82


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