UMLS:C0026986 - FACTA Search

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Query: UMLS:C0026986 (myelodysplastic syndrome)
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Allogeneic bone marrow transplantation (BMT) is the treatment of choice for hematologic malignancies resistant to conventional chemotherapy and for patients who are at high risk for relapse. Until recently, no cure could be offered to patients relapsing following allogeneic BMT. We present our long-term observations of the first patient with remission reinduced by allogeneic cell therapy (allo-CT) using donor peripheral blood lymphocytes (PBL). In addition, we review the cumulative international experience with allo-CT used to treat 163 patients, 105 with CML and 58 with other hematologic diseases, who relapsed following allogeneic BMT. The first patient treated by allo-CT was diagnosed with acute resistant pre-B lymphoblastic leukemia (ALL) in extensive third hematologic and extramedullary relapse shortly after BMT. He was given infusions of donor (sister) PBL in multiple increments. Subsequently, he developed mild, reversible graft-vs-host disease (GVHD) in parallel with regression of all hematologic and cytogenetic disease manifestations. More than 8 years after allo-CT, he is disease-free with Karnofsky score 100% and no evidence of residual male cells by PCR. International data show that relapse after BMT was successfully reversed by donor PBL treatment in 97 of 158 evaluable patients; 72/100 (72%) with chronic myeloid leukemia (CML) and 25/58 (44.8%) with other malignant hematologic diseases including acute leukemia, lymphoma, and myelodysplastic syndrome. T cell depletion (TCD) for prevention of GVHD was performed for 60/105 (57%) patients with CML and 31/58 (53.4%) patients with other hematologic malignancies. Complete response after allo-CT was obtained in recipients of both TCD-BMT and unmodified BMT. GVHD due to allo-CT developed in 86/158 (54.4%) of the patients, 63/100 (63.0%) with CML and 23/58 (39.6%) with other hematologic diseases. alpha-interferon (IFN-alpha) was given to 67.9% of patients with CML and 28.1% of patients with other diseases. The cumulative experience shows that allo-CT can successfully reverse chemoradiotherapy-resistant relapse of acute leukemia and even more effectively of chronic leukemia independently of alpha-interferon therapy. Although GVHD was frequent among responders, accompanied occasionally by transient or irreversible marrow aplasia, remissions were also obtained in patients with no GVHD. Allo-CT should therefore be considered as treatment of choice for overt relapse or de novo minimal residual disease post-BMT. Administration of donor peripheral blood lymphocytes in graded increments at an early stage of relapse may be the best approach for combining optimal timing at the stage of minimal disease while controlling and minimizing the risk of GVHD on an individual basis.
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PMID:Allogeneic cell therapy for relapsed leukemia after bone marrow transplantation with donor peripheral blood lymphocytes. 854 46

The option of bone marrow transplantation (BMT) significantly improved prognosis of adult patients with hematologic malignancies aged less than 50 years. Allogeneic BMT using the marrow of an HLA-identical family member still provides the most effective method of BMT. Conventional indications for this form of BMT are chronic myeloid leukemia (CML), acute leukemias presenting with adverse risk factors, myelodysplastic syndromes and severe aplastic anemia. If performed early in the disease course (e.g. during the chronic phase of CML or first remission of acute leukemia and MDS) allogeneic BMT cures 50 to 60% of patients. About 20% die of therapy related complications, e.g. graft versus host disease (GvHD), fatal infections or venoocclusive disease of the liver (VOD) and about 20% of patients succumb to relapse of their hematologic disorder. 80% presenting with severe aplastic anemia can be cured, if allogeneic BMT is performed soon after diagnosis without previous immunosuppressive therapy and blood transfusions. BMT with the marrow of a matched unrelated donor or autologous BMT are increasingly used as alternative procedures. A rate of lethal complications as high as 50% hinders rapid extension of BMT with unrelated donors. Therefore, this form of BMT should be restricted to young patients with leukemias, who cannot achieve long-term remission with conventional chemotherapy (in case of acute leukemias) or alpha-interferon (in case of CML). Reconstitution of hematopoiesis is more rapid after peripheral blood stem cell transplantation (PBSCT) compared with autologous BMT. Therefore, PBSCT will replace autologous BMT in most cases. Most favourable results of PBSCT have been reported in patients with malignant lymphomas after relapse or inferior response to primary induction therapy. Due to the higher relapse rate autologous BMT is inferior to allogeneic BMT in leukemia patients. Trials are required to clarify the potential role of myeloablative therapy with stem cell support in the treatment of patients with solid tumors. Many of the preliminary results already published are unsatisfactory and data of larger trials are still lacking. Therefore, BMT or PBSCT cannot be recommended generally for the therapy of patients with solid tumors.
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PMID:[Indications, technique and risks in bone marrow transplantation in adulthood]. 864 1

Procoagulant activity (PCA) of peripheral mononuclear cells (PMC) was evaluated in patients with primary thrombocythemia (PT, group A), polycythemia vera (PV), idiopathic myelofibrosis (IM) and myelodysplastic syndromes (group B), and in 15 healthy subjects as control group. PCA of PMC was assayed under basal conditions and after agonist-induced stimulation: bacterial lipopolysaccharide, glycosylated granulocyte-macrophage colony-stimulating factor, recombinant alpha-interferon. PCA was similar in the control group and group A when no stimulation was used, while PCA was found significantly higher in group B patients in the same conditions. In group A patients and in the control group, but not in group B patients, a lower PCA expression was found when PMC were simultaneously coincubated with LPS and alpha-interferon with respect to LPS incubation alone.
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PMID:Procoagulant activity of mononuclear cells is increased in myeloproliferative and myelodysplastic diseases. 873 90

Interferon Regulatory Factor-1 (IRF-1) acts as a transcriptional activator in interferon system and as a tumor suppressor. The loss of functional IRF-1 has been shown in approximately 30% of patients with myelodysplastic syndrome (MDS) and overt leukemia from MDS. Here we report an alternative mechanism of inactivation of IRF-1 activity. We identified an IRF-1 binding protein (IRF-BP). Protein sequencing revealed that IRF-BP was identical to nucleophosmin (NPM), a nucleolar phosphoprotein. Functional analysis showed that IRF-BP inhibited DNA-binding and transcriptional activity of IRF-1. Moreover when we examined several leukemia samples, the level of IRF-BP mRNA was increased. These results are consistent with the hypothesis that IRF-BP binds to IRF-1, and that overexpression of IRF-BP in leukemias leads to escape from IRF-1-regulated growth control. This hypothesis was also supported by the fact that overexpression of IRF-BP in NIH 3T3 cells rendered cells transformed.
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PMID:[Identification and analysis of IRF-1 binding protein]. 880 74

To assess the clinical value of determination of the interferon (IFN)-producing capacity of patients, IFN production induced by Sendai virus (HVJ) in vitro was measured in cell cultures of whole blood from patients with various diseases. IFN production in patients with lung cancer, myelodysplastic syndromes, noninsulin-dependent diabetes mellitus, pulmonary tuberculosis, and asymptomatic HIV-1 infection was lower than that in healthy persons. Furthermore, periodic measurements of IFN production revealed decreasing IFN producing capacities in patients with lung cancer with progression of the tumor stage. However, increased IFN-producing capacities were observed in patients with tuberculosis after standard therapy. Further experiments showed that the main type of IFN induced in whole blood cultures was IFN-alpha, and decreased IFN production in patients did not result from a decreased number of leukocytes but rather from an impairment of cellular IFN production. The evaluation of IFN production in whole blood cell cultures may be a feasible method of assessing the impaired immune status.
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PMID:Determination of interferon-alpha-producing capacity in whole blood cultures from patients with various diseases and from healthy persons. 893 66

This report suggests modest changes in the criteria used for the diagnosis of ET and allows tentative recommendations concerning therapy. As outlined in Table I, we believe that absent stainable marrow iron does not necessarily indicate iron deficiency in these patients and that the serum ferritin and RBC mean corpuscular volume should be incorporated in this assessment. Normal values speak strongly against iron-deficient erythropoiesis. A search for the bcr/abl gene rearrangement should be included with the marrow karyotype to exclude CML. Finally, cytogenetic data and morphologic study of the marrow should be used to be certain that a MDS should not be considered. It may be that measurements of serum thrombopoietin levels may be useful in the future. Nonetheless, in principle, ET remains a diagnosis of exclusion as we have originally suggested. For therapy, HU remains an excellent choice for the older patient at risk for thrombosis. Nonetheless, no myelosuppressive therapy remains a perfectly viable option, particularly for the young patient and the older with low thrombotic risk. The roles of anagrelide and alpha interferon in this setting have not been fully defined. Experience with both has still been relatively short. It would be ideal if prospective, randomized trials could be mounted to address these questions. We conclude with confidence that return to older approaches such as 32P and AA in patients who fail on HU is to be discouraged. The use of anagrelide or interferon alfa seems to be a much more appropriate approach. We have not investigated the role of antithrombotic agents such as aspirin in ET. In PV, the combination of aspirin, 300 mg three times daily, and dipyridamole, 75 mg three times daily, failed to reduce the rate of thrombosis and was associated with an increased rate of hemorrhage. It is rational to suggest that lower doses of aspirin (ie, < 325 mg daily) might be associated with less hemorrhage and, perhaps, a beneficial effect on thrombosis. This remains to be shown.
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PMID:Experience of the Polycythemia Vera Study Group with essential thrombocythemia: a final report on diagnostic criteria, survival, and leukemic transition by treatment. 902 60

A 40-year-old male with Ph-positive CML underwent PBSC autografting after initial treatment with hydroxyurea and interferon. Following autograft he remained in chronic phase with cytogenetic or molecular evidence of low levels of residual Ph-positive cells. However, additional cytogenetic abnormalities, including t(3;21) typically seen in therapy-related myelodysplastic syndrome (MDS) and AML and blast crisis of CML, developed as an independent cell line following the autograft. More than 4 years after the autograft, the patient remains in chronic phase with no evidence of accelerated phase or blast crisis of CML, but with a concurrent MDS. We report a case of CML who developed therapy-related MDS following PBSC autograft while still remaining in chronic phase.
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PMID:t(3;21) following peripheral blood stem cell transplantation in chronic phase chronic myeloid leukaemia. 920 22

Myelodysplasia and the myeloproliferative disorders are clonal hematopoietic stem cell disorders with heterogeneous clinical presentations and prognoses. This review highlights some of the recent progress that has been made in these disorders. Specifically, a number of studies have enhanced our understanding of the pathogenesis of these disorders, and potentially useful animal models for primary myelofibrosis have been developed. New, clinically useful prognostic scoring systems have been devised for myelodysplasia and for primary myelofibrosis. New chemotherapeutic approaches and nonmyelosuppressive alternative therapies for myelodysplasia have been studied. Data on the use of interferon for polycythemia vera and the potential leukemogenesis of hydroxyurea have recently become available. Finally, continued progress has been made in the use of allogeneic (related and unrelated donor) and autologous stem cell transplantation for myelodysplasia.
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PMID:Myelodysplasia and myeloproliferative disorders. 926 54

Interferon regulatory factor-1 (IRF-1) acts as a transcriptional activator in the interferon system and as a tumor suppressor. The loss of functional IRF-1 has been observed in a significant number of patients with myelodysplastic syndrome (MDS) and leukemia, suggesting a potentially critical role of IRF-1 in human oncostasis. Here we report an alternative mechanism by which IRF-1 may be inactivated. We purified an IRF-1 association molecule which was revealed to be identical to a nuclear factor nucleophosmin (NPM)/B23/numatrin. Functional analysis showed that NPM inhibited the DNA-binding and transcriptional activity of IRF-1. Moreover, NPM was overexpressed in several clinical leukemia samples and human-derived leukemia cell lines. Finally, overexpression of NPM in NIH3T3 cells resulted in malignant transformation. These results suggest the possible involvement of NPM in inactivating IRF-1-dependent anti-oncogenic surveillance in human cancer development.
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PMID:Identification and characterization of nucleophosmin/B23/numatrin which binds the anti-oncogenic transcription factor IRF-1 and manifests oncogenic activity. 931 94

WHAT IS HYPOPLASTIC ANEMIA? Aplastic anemia is a hematological disease characterized by pancytopenia and bone marrow hypoplasia. Acquired cases of aplastic anemia are almost all idiopathic and arise from unknown causes. Other cases of aplastic anemia are secondary and are caused by radiation, chemicals or viruses. PATHOPHYSIOLOGY: Aplastic anemia is manifested as a marked reduction in the number of pluripotent hematopoietic stem cells, but why this occurs is still uncertain. Some of the proposed causes include abnormalities of the hematopoietic stem cells, abnormalities in the hematopoietic microenvironment, and immunologically mediated damage to the hematopoietic stem cells (Figure 1). ABNORMALTIES OF THE HEMATOPOIETIC STEM CELLS: Patients with aplastic anemia, and long-term survivors in particular, are at increased risk of developing paroxysmal nocturnal hemoglobinuria (PNH), myelodysplastic syndrome (MDS), or acute myelocytic leukemia. This suggests that, in at least some of these patients, the hematopoietic stem cells themselves are abnormal. It also suggests that in some of these patients the blood cells are clonal (that is, all the blood cells are derived from a single pluripotent stem cell). In short, what these findings imply is that aplastic anemia may be caused by the emergence of an abnormal clone. Clonal hematopoiesis, however, can also be considered nothing more than a consequence. In other words, it is possible that hematopoiesis in this kind of patient is performed by a lone pluripotent stem cell that somehow managed to survive eradication. No definitive interpretation of clonal hematopoiesis has been agreed upon, and it is still a topic for future research. ABNORMAL HEMATOPOIETIC MICROENVIRONMENT: The presence of stromal cells, which form the microenvironment of bone marrow, is very important in hematopoiesis. Hematopoietic stem cells proliferate and differentiate either by adhering to stromal cells or by being stimulated by the various hematopoietic factors that stromal cells produce. Therefore, it is quite possible that aplastic anemia is caused by abnormalities in the hematopoietic microenvironment. However, many separate studies have demonstrated that the hematopoietic microenvironment in the vast majority of aplastic anemia cases is normal. IMMUNE MECHANISMS: Immunosuppressive agents are often effective in treating aplastic anemia, and therefore it is believed that immunological mechanisms contribute to the disease in more than half the cases. The following mechanisms have been proposed as causes for the onset of immunologically mediated aplastic anemia: * Decreases in Hematopoietic Factors Produced by Monocytes and Lymphocytes. Some patients with aplastic anemia show decreased production of interleukin 1 (IL-1) by peripheral blood monocytes, and it is possible that a drop in the concentration of this factor is linked to the onset of the disease [1]. It is also possible, however, that decreased IL-1 production by monocytes is not a cause of the disease, but merely a consequence. Moreover, no cases have been reported that exhibit reduced production of hematopoietic factors produced by lymphocytes such as GM-CSF, IL-3, or IL-6. * Damage by Cytokines that Suppress Hematopoiesis. It has been reported that increased levels of interferon &ggr; (IFN-&ggr;), which is produced by lymphocytes, and tumor necrosis factor &agr; (TNF-&agr;), which is produced by monocytes and macrophages, are found in the bone marrow and peripheral blood of aplastic anemia patients [2, 3]. These two factors act as suppressors of hematopoiesis, and it is possible that they contribute to the disease. The increase of these inflammatory cytokines in the bone marrow strongly suggests the presence of either specific or non-specific destruction of the hematopoietic stem cells by immunoregulatory cells. * Suppression of Hematopoiesis by Cytotoxic T Cells (Killer T Cells). Cases have been reported in which cytotoxic T cell clones that damage the autologous hematopoietic precursor cells are present [4]. Therefore, we can easily conceive of a mechanism in which these cytotoxic T cells specifically destroy the hematopoietic stem cells and cause aplastic anemia. * Suppression of Hematopoiesis by Natural Killer (NK) Cells. NK activity of aplastic anemia patients is depressed, and, generally speaking, it is highly unlikely that NK cells contribute to this condition. However, it has been reported that clonal NK cells are thought to cause the disease in patients exhibiting pancytopenia and bone marrow hypoplasia. Therefore, when this disease is diagnosed, a peripheral blood granular lymphocyte count and NK cell surface marker analysis should always be performed. DIAGNOSIS: A necessary condition for the diagnosis of aplastic anemia is the presence of pancytopenia. Moreover, it is necessary to rule out all other causes of pancytopenia. It is especially important in differential diagnosis to look for PNH and MDS. In cases of aplastic anemia there are patients that exhibit PNH during the course of the disease, and this condition is called aplastic anemia-PNH syndrome. It has recently been shown that bone marrow and peripheral blood cells in some patients diagnosed with aplastic anemia are partially lacking GPI anchor proteins (CD16, CD55, and CD59) [5]. Whether such patients become to exhibit aplastic anemia-PNH syndrome in the future remains to be elucidated. In MDS the bone marrow generally exhibits normoplasia or hyperplasia, and only in rare cases does it exhibit hypoplasia. This condition is referred to as hypoplastic MDS. Hypoplastic MDS can be differentiated from aplastic anemia by the presence of abnormal cell morphology that is sometimes accompanied by chromosomal abnormalities. TREATMENT:Aplastic anemia is treated with androgens, high-dose methylprednisolone, cyclosporin A (CyA), antithymocyte globulin (ATG), antilymphocyte globulin (ALG), hematopoietic growth factors such as G-CSF, and bone marrow transplantation. Interestingly, patients who require continuous CyA administration to maintain stable hematopoiesis have a specific HLA class II haplotype (DRB1*1501-DQA1*0102-DQB1*0602) [6]. Recent reports from EBMT SAA Working Party showed the excellent therapeutic result (response rate 82%) when severe cases were treated with ALG, CyA and G-CSF in combination [7].
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PMID:Special Education: Aplastic Anemia. 1038 86

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