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)

Rates of proliferation, apoptosis and cytokine expression were measured in bone marrow (BM) biopsies of 164 myelodysplastic syndrome (MDS) patients. There were 107 males and 57 females. Median age was 69 years and 101 had refractory anemia (RA), 17 RA with ringed sideroblasts (RARS), 38 with RA and excess blasts (RAEB) and 8 with RAEB in transformation (RAEB-t). Apoptosis measured by in-situ end labeling (ISEL) was directly related to the number of macrophages (p = 0.028, n = 83). Mean tumor necrosis factor alpha (TNF-alpha) and ISEL positivity were higher in RAEB + RAEB-t patients (p = 0.0554 and p = 0.06 respectively) while hemoglobin was higher for RA + RARS group (p = 0.0472). Patients with high apoptosis had lower white blood cell counts (p = 0.0009), lower percentage of blasts (p = 0.0009) and higher number of macrophages (p = 0.0086). We conclude that measurements of apoptosis, proliferation and cytokine expression provide important biological information which helps to distinguish RA + RARS patients from RAEB + RAEB-t patients, and may be of additive prognostic significance.
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PMID:Biologic characteristics of 164 patients with myelodysplastic syndromes. 1022 7

Rates of proliferation and apoptosis as well as expression of tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and the number of macrophages were measured in bone marrow (BM) biopsies of 33 patients who presented with hypocellular (cellularity < 30%) myelodysplastic syndromes (MDS). Results showed that 2/3 of the patients had high apoptosis, high cytokine levels and large number of macrophages in their biopsies while 1/3 did not. Apoptosis and TNF-alpha levels were directly related (r = 0.583, P = 0.003, n = 24) as was apoptosis and the degree of anemia (P = 0.033, n = 18). A subgroup of patients with abnormalities of chromosomes 5 or 7 had higher platelets (P = 0.026) and higher apoptosis (P = 0.038) when compared with the rest of the group. Eight patients had no evidence of apoptosis and almost no detectable TNF-alpha in their biopsies. We conclude that within the hypocellular variant of MDS, there may be two distinct sub-groups of patients, one who present with high cytokine-mediated intramedullary apoptosis and the other who may be better characterized as having a stem-cell failure defect since they showed no evidence of apoptosis.
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PMID:Biologic characteristics of patients with hypocellular myelodysplastic syndromes. 1022 21

A 12-year-old boy with myelodysplastic syndrome underwent a double transplantation of hematopoietic progenitor cells from his haploidentical brother. After conditioning with busulfan, cyclophosphamide, and Vepesid, the first bone marrow transplantation was performed using 3.53 x 10(6)/kg of CD34+ cells. Initial engraftment was followed by graft rejection. The second conditioning consisted of melphalan and anti-thymocyte globulin. The boy was then transplanted with 5.15 x 10(6)/kg of CD34+ cells, harvested from bone marrow (BM) and peripheral blood. Graft versus host disease (GvHD) prophylaxis consisted of cyclosporine A + short methotrexate. Hematological recovery was rapid and stable. Acute GvHD 1 degree (skin) resolved after 2 weeks of steroid treatment. A relapse occurred on day +140. At that time NK cells decreased from 20 to 7% with the lowest CD4+/CD8+ ratio, 0.07. Just after relapse, the percentage of cytokine-induced killer cells (CIK-CD3+CD56+) dropped from 3.34 to 0.1%. CsA treatment was stopped and the patient received T cell (CD3+ cells) add-back four times on days +146, +199, +234, and +262 in doses of 0.5 x 10(5), 1.0 x 10(5), 2.0 x 10(5), and 4.0 x 10(5)/kg, respectively. No acute GvHD occurred. Additionally, bone marrow biopsy before the second add-back showed complete remission. Analysis of lymphocyte subsets before the fourth add-back showed the highest values of CD4+, NK, and CIK cells and also the highest CD4+/CD8+ ratio.
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PMID:Double haploidentical transplantation of hematopoietic progenitor cells in a boy with myelodysplastic syndrome. 1032 25

The phosphorylated thiol amine, amifostine (Ethyol; Alza Pharmaceuticals, Palo Alto, CA/US Bioscience, West Conshohocken, PA), is a cytoprotective agent for cisplatin-based chemotherapy. Recent investigations have given rise to new potential applications of amifostine in hematologic malignancies. Amifostine appears to exert a sustained mitogenic effect in primitive hematopoietic progenitors that results in a significant increase in colony-forming capacity. Amifostine also retards cell loss and delays commitment to apoptosis initiated by cytokine deprivation, suggesting that amifostine has trophic effects similar to the hematopoietic cytokines. The abilities to prolong progenitor survival and to delay apoptosis under conditions of cellular stress make amifostine an attractive agent for investigation in bone marrow failure states. Amifostine promotes more effective hematopoiesis in patients with myelodysplastic syndrome, although additional investigation is needed to further define the optimal dose and schedule of administration. Furthermore, amifostine may selectively enhance the cytotoxicity of chemotherapeutic agents in leukemia progenitors. When the sensitivity of leukemic and normal progenitors to mafosfamide was evaluated with and without amifostine pretreatment, amifostine effectively protected normal myeloid and erythroid progenitors while increasing leukemic cell kill. Thus, amifostine represents a unique agent with promising potential for therapeutic application in hematologic malignancies. Further investigation is needed to define its role in clinical practice.
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PMID:Use of amifostine in hematologic malignancies, myelodysplastic syndrome, and acute leukemia. 1034 62

In this study, we examined the role of Fas-signaling in the apoptotic pathway in myelodysplastic syndromes (MDS). Ficoll-separated mononuclear cells from 18 bone marrow aspirate specimens obtained from 17 MDS patients, 4 normal healthy donors, and 3 acute myeloid leukemia patients transformed from MDS (t-AML) were studied for mRNA expression of Fas-L, Fas, and the effectors of their signaling, Caspase 1 and Caspase 3, using reverse transcriptase polymerase chain reaction. Fas-L, Fas, and Caspase 1 were detectable in all of the samples in the three groups. Caspase 3 was detectable both in MDS and t-AML specimens but was negligible in normal cells. The apoptotic index (AI%) determined by in situ end labeling of fragmented DNA in 4-hour cultures of mononuclear cells was significantly higher in MDS cells compared to normal or t-AML cells (mean +/- SEM: 2.3% +/- 0.4% in MDS, n = 10 vs. 0.6% +/- 0.2%, n = 4, P = 0.014 in normal cells, and 0.2% +/- 0.2%, n = 3, P = 0.007 in t-AML cells). Treatment of MDS cells with anti-Fas-L antibody suppressed apoptosis (AI%: 2.1% +/- 0.6% in untreated vs. 1.37% +/- 0.5% in treated, n = 6, P = 0.02), indicating functional participation of Fas-signaling in MDS. Further, it was found that Fas-L, Fas, and Caspase 1 mRNA expression remained unchanged in 4 hours. Caspase 3 expression appeared in normal cells after 4 hours and was present at both 0 and 4 hours in MDS and t-AML cells. In contrast to persistent expression in normal and t-AML cells, cells from the 5 MDS patients studied consistently showed significantly lowered or undetectable expression of a negative regulator of Fas, called Fas-associated phosphatase-1 (Fap-1) after 4 hours. Thus, the high AI% in MDS corresponds to a rapid decline in Fap-1. Furthermore, in tumor necrosis factor alpha (TNF-alpha) treated HL60 promyelocytic cells, a definite periodicity in the expression of different mRNAs was observed with upregulation of TNF-alpha itself at 30 minutes, increased expression of Fas and the appearance of Fas-L after 2 hours, and a decrease in Fap-1 expression after 8 hours. These results suggest that TNF-alpha not only induces the effectors of Fas-signaling but also may downregulate the inhibitor. We conclude that a spontaneous and rapid down-regulation of Fap-1, possibly induced by TNF-alpha, a cytokine shown to be present in excess in MDS marrows, may underlie the increased apoptotic death of hematopoietic cells in these patients. Interference with Fap-1 turnover may provide a new therapeutic modality for MDS.
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PMID:Spontaneous down-regulation of Fas-associated phosphatase-1 may contribute to excessive apoptosis in myelodysplastic marrows. 1049 46

The myelodysplastic syndromes (MDS) are a heterogenous family of hematologic disorders characterized by ineffective hematopoiesis. Because of the variability between patients regarding prognosis and morbidity related to the disease, consensus regarding the management of these patients has been difficult. Over the past several years, new prognostic scoring systems such as the International Prognostic Scoring System (IPSS) have attempted to provide a projection for long-term stability of the percentage of patients who have "low-grade" or indolent MDS. Unfortunately, its lack of prospective use in clinical trials and other settings has thus far failed to validate it as a functional decision-making tool. Thus, investigators have hypothesized that separating patients based on more simplistic treatment-oriented guidelines may be more efficient. For the majority of patients with MDS, no curative option exists. Patients who are young enough and have an available matched sibling or matched unrelated donor may undergo an allogeneic bone marrow transplant (BMT) with a potential cure rate of 30% to 50%. The major issue regarding this approach is the relatively high morbidity and the risk that the patient's lives may be shortened, that their quality of life will be worsened, or that no overall benefit will occur (relapse). Compounding the issue of selection and timing for BMT is the fact that the best results in terms of relapse-free survival appear to be in the subset of patients with early or low-grade MDS, characterized by refractory anemia with or without ringed sideroblasts. For these patients, lacking a donor for BMT, the major issue has become the consideration of induction chemotherapy. While dose-intensive chemotherapy may improve outcome in a small percentage of patients, the majority of elderly patients with MDS are not optimal candidates for such an approach. As a result, supportive care has a major role for patients with MDS and depending on the French-American-British (FAB) presentation and comorbid illnesses may be the preferred approach. Erythropoietin, a growth factor, is perhaps the most commonly used supportive care after transfusion. The use of colony-stimulating growth factors to support leukopenia is currently under investigation. The use of thrombopoietic agents has lagged behind in the management of MDS patients. Investigation of interleukin-6 (IL-6), a thrombopoietic cytokine, showed some ability to increase platelets through significant toxicity. Investigation of IL-11, an approved thrombopoietic growth factor, is preparing to start and should aid in determining its role in this setting.
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PMID:Advances in supportive care of myelodysplastic syndromes. 1053 Jul 13

A case of hemophagocytic syndrome (HPS) refractory to corticosteroid therapy was successfully treated by plasma exchange. The patient was a 56-year-old woman who had undergone regular hemodialysis for 10 years for complicated myelodysplastic syndrome (MDS) and then had had lung tuberculosis. After the onset of tuberculosis, she suffered from HPS and was treated by antituberculosis agents and high dose corticosteroid administration without any effect on the HPS. After adding a series of plasma exchanges, the HPS improved gradually, and her MDS began to respond to corticosteroid therapy. Plasma hypercytokinemia due to HPS was corrected by plasma exchange, and the correction of a high level of plasma inflammatory cytokine was considered to be one of the contributing factors for the improvement of HPS. These results suggest that therapeutic plasma exchange should be considered as a therapeutic tool for HPS refractory to conventional therapy.
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PMID:Effect of plasma exchange on refractory hemophagocytic syndrome complicated with myelodysplastic syndrome. 1060 26

Between October 1995 and October 1998, 24 children aged 9 months to 17 years (median 11 years) underwent cytokine-mobilized allogeneic peripheral blood stem cell (PBSC) transplantation for treatment of hematological disorders. All of the transplants were the first allogeneic transplant for the recipient. Twenty patients were transplanted for hematological malignancies (ALL = 8, AML = 6, CML = 4, MDS = 2) and four patients were transplanted for non-malignant disease (thalassemia major = 2, Wiskott-Aldrich syndrome = 1, Kostmann's syndrome = 1). Nineteen donors were HLA-identical siblings, four were HLA-matched or single antigen mismatched parents, and one was a syngeneic transplant. Donors aged 8 to 38 years (median 15 years, 14 donors <18 years) received G-CSF 10 microg/kg/day subcutaneously beginning 4 days before PBSC collection and were submitted to one to three leukapheresis collections. The median CD34+ cell yield was 7.8 x 106 cells/kg recipient body weight. All patients achieved an ANC >0.5 x 109/l after a median of 13 days (range 10-21). Twenty-three patients eventually achieved platelet transfusion independence. One patient died on day 63 without ever achieving platelet transfusion independence. Four patients received platelet transfusions to maintain a platelet count well above 20 x 109/l due to bleeding complications. Of the 19 evaluable patients, the median time to a non-transfused platelet count of 20 x 109/l was 12 days (range 0-44). Ten of 23 at-risk patients developed acute GVHD grades II to IV, with grades III to IV in four patients. Twelve of 19 patients followed for at least 100 days have developed chronic GVHD (extensive = 2, limited = 10) with an actuarial risk of chronic GVHD of 75% at 1 year. The Kaplan-Meier estimate of event-free survival is 65% at 2 years. Four patients died (GVHD = 3, VOD = 1), three patients relapsed, and one patient with thalassemia major had a late graft failure with autologous recovery. Based upon our experience, allogeneic PBSCT is safe for both pediatric donors and recipients and engraftment of neutrophils and platelets is rapid. Bone Marrow Transplantation (2000) 25, 13-18.
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PMID:Cytokine-mobilized allogeneic peripheral blood stem cell transplants in children result in rapid engraftment and a high incidence of chronic GVHD. 1065 8

To investigate the pathogenesis of immunological abnormalities (IA) in myelodysplastic syndrome (MDS), we examined B cells for their ability to produce cytokine and their X chromosome inactivation pattern (XCIP). An IA was defined as being positive for at least one autoimmune laboratory test (e.g. antinuclear antibody, rheumatoid factor). Seventy-three MDS patients [65 with refractory anemia (RA), 3 with RA with excess blasts (RAEB), and 5 with RAEB in transformation] were examined; 47 had IA and 26 had no IA. To examine the function of B cells in MDS, the production of interleukin (IL)-6 and IL-10 was measured in cultures of purified B cells with or without stimulators. Both IL-6 and IL-10 production rates in patients with IA were significantly higher than in patients without IA and normal controls. The skewing of XCIP of B cells was analyzed by using the polymerase chain reaction, and the skewing rate of B cell XCIP was quantitatively assayed by compared to control T lymphocytes. The skewing rate of B cells was higher in patients with IA than in those without IA and normal controls. Therefore, a small population of B cells in patients with IA might be derived from MDS clones, and be associated with the induction of IA.
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PMID:Function and X chromosome inactivation analysis of B lymphocytes in myelodysplastic syndromes with immunological abnormalities. 1069 74

A comparison was made of the cytokine transcripts in normal, monoclonal, MDS, and AML marrow aspirates. While both normal and monoclonal marrow aspirates contain transcripts for SCF, few MDS or AML marrow aspirates contain these transcripts. Similarly, IL1ra transcripts are found with reduced frequency in MDS and AML marrow aspirates. The fall in SCF transcripts between monoclonal and MDS marrow aspirates parallels the appearance of apoptosis and the reduced in vitro proliferative ability which are characteristics of MDS marrow aspirate cells. The frequent IL1beta production by MDS and AML marrow aspirate cells, with few marrow aspirates producing IL1ra transcripts, suggests that unbalanced IL1beta effects may contribute to the proliferative advantage of MDS and AML cells over their normal counterparts.
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PMID:Marrow cytokine transcripts and the secondary hematologic disorders. 1070 53


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