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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent progress of molecular biology and gene technology has developed a novel approach of clinical treatment. Several recombinant cytokines are already applied to clinical field. In this symposium, I introduced clinical application of some cytokines including GM-CSF, interleukin (IL)-1 and IL-3. The clinical benefits of IL-1 are; 1) IL-1 has an anti-tumor effect especially on cutaneous lymphoma and brain tumors, and 2) IL-1 has a function as hematopoietic growth factor for very immature hematopoietic stem cells. In the clinical Phase I/II study, IL-1 has been shown to have anti-tumor effect on cutaneous T-lymphoma via immune mechanisms. The side effects of IL-1 were variable including fever, fatigue, skin redness and so on, but they were all tolerable. The clinical phase studies of GM-CSF and IL-3 are now on going. The preliminary studies show that GM-CSF has granulo-poietic activity but not thrombo-poietic activity, and that IL-3 has multi-hematopoietic activity. These cytokines may be useful for treatment of disorders of hematopoietic stem cells such as aplastic anemia and myelodysplastic syndrome. The side effects of both cytokines are resemble, but all are tolerable.
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PMID:[Clinical application of new cytokines]. 835 Apr 99

Similar to two other hematopoietic growth factor receptors, the c-fms (macrophage colony-stimulating factor receptor) and the c-kit genes, c-mpl has been discovered through the study of oncogenic retroviruses. Unlike c-fms and c-kit, which both belong to a subgroup of tyrosine kinase receptors, the c-mpl proto-oncogene encodes a new member of the cytokine receptor superfamily. We have studied the expression of c-mpl in a series of 105 patients with hematologic malignancies using Northern blot analysis. The levels of c-mpl transcripts in lymphoid malignancies and in chronic myeloproliferative disorders were not significantly different from those found in normal bone marrow cells, in which c-mpl was barely detectable. In contrast, c-mpl expression was increased in 26 of 51 patients with acute myeloblastic leukemia (AML) and in 5 of 16 patients with myelodysplastic syndromes. Amplification of the c-mpl gene was detected in genomic DNA of one M4 AML patient. There was no significant correlation between c-mpl expression and the French-American-British classification of AML. Patients with high c-mpl expression appeared to belong to a subgroup of AML with a low rate of complete remission and a poor prognosis, including secondary leukemia and AML with unfavorable cytogenetic abnormalities.
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PMID:Expression of the c-mpl proto-oncogene in human hematologic malignancies. 839 55

Investigations of the effects of hematopoietic growth factors (HGFs) on the cell cycle of cells from myelodysplastic syndrome (MDS) have been hampered by technical difficulties. In this study, using a recently established flow cytometric method that enables detailed analysis of the cell cycle (Gzero-, G1-, S-, and G2/M-phases) of target cells in a heterogeneous cell population, we examined the effects of granulocyte colony-stimulating factor (G-CSF) and other HGFs on the cell cycle of CD13-positive cells (blasts and other malignant myelocytic and monocytic cells) in MDS. The cell cycle response to G-CSF (decrease in Gzero-phase cells and increase in S-phase cells) was heterogeneous among MDS cases. When the data for 13 MDS cases and 15 de novo AML cases were compared statistically, the magnitude of cell cycle activation by G-CSF was weaker for the cells from the MDS cases. Stem cell factor, interleukin-3, or a combination of these HGFs with G-CSF reduced the Gzero-phase cell percentage in all examined MDS cases whose cell cycle was unresponsive to G-CSF alone. When cytosine arabinoside was added to cells with or without stimulation by HGFs, the viable G0-phase cell count was reduced in HGF-stimulated cells compared with unstimulated cells in seven of eight cases. The present results suggest that G-CSF-induced cell cycle stimulation of malignant cells can be expected in a fraction of MDS patients and that even in MDS patients whose cells do not respond to G-CSF, employment of other HGFs and their combination with G-CSF is worth consideration. The results also suggest that a well-designed therapy using HGFs and chemotherapeutic drugs may reduce the quiescent (Gzero) cell count in MDS, which is assumed to be responsible for drug resistance derived from cell kinetics.
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PMID:Cell cycle modulation by hematopoietic growth factors in myelodysplastic syndromes: analysis by three-color flow cytometry. 898 1

Thrombopoietin (TPO) is a novel hematopoietic growth factor that was cloned as a ligand for c-mpl proto-oncogene. The c-mpl proto-oncogene is expressed on various types of human leukemia cell lines derived from erythroid, megakaryocytic, and stem-cell leukemia cells. Also, c-mpl mRNA is detectable on blast cells in about half of acute myeloblastic leukemia (AML) cases regardless of French-American-British (FAB) classification. In the cases with myelodysplastic syndrome, c-mpl is expressed in a substantial fraction of refractory anemia with excess of blast (RAEB), RAEB in transformation, and chronic myelomonocytic leukemia cells, but not in refractory anemia or sideroblastic anemia. Little or no expression of c-mpl mRNA is observed in human lymphoid cell lines and blast cells of acute lymphoblastic leukemia cases. The in vitro treatment of AML cells with TPO resulted in proliferation in about 70% of c-mpl-positive AML cases. The proliferative responses of AML cells to TPO were observed not only in M7-type, but also in the other subtypes of AML cases. Furthermore, the TPO-induced proliferation of AML cells was augmented by the addition of the other hematopoietic growth factors such as interleukin-3 (IL-3), IL-6, stem cell factor, or granulocyte-macrophage colony-stimulating factor. In addition to proliferation, TPO appeared to induce megakaryocytic differentiation in a small part of AML cells. These results suggested that TPO/c-mpl system might contribute, at least in part, to abnormal growth and differentiation of AML cells.
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PMID:The effects of thrombopoietin on the growth of acute myeloblastic leukemia cells. 903 Oct 83

Interleukin-3 (IL-3) is a pleiotropic cytokine which has stimulatory effects on a broad range of hematopoietic progenitor cells. These effects have led to the use of IL-3 in clinical trials for the treatment of aplastic anemia and myelodysplastic syndrome as well as to stimulate bone marrow recovery in patients who have received high-dose therapy and bone marrow/stem cell transplantation. However, because one study suggested that IL-3 may also stimulate the growth of follicular small cleaved cell lymphoma (FSCCL) cells in vitro, it was concerning that the use of IL-3 after bone marrow transplantation in patients with FSCCL may stimulate the growth of undetectable minimal residual tumor cells resulting in early relapsed disease. In contrast to these observations, our own in vitro studies demonstrated that IL-3 inhibited FSCCL cells in short-term culture in a dose-dependent manner. Subsequently, we conducted a phase II clinical trial using single agent IL-3 for the treatment of patients with follicular low grade lymphoma. Our clinical data did not support the hypothesis that IL-3 is a growth stimulator of FSCCL.
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PMID:In vitro and in vivo biologic effects of interleukin-3 (IL-3) in follicular low-grade lymphoma. 925 Jul 83

C-mpl ligand acts primarily as a lineage-specific hematopoietic growth factor by promoting proliferation of megakaryocyte precursors and their differentiation into megakaryocytes and platelets. In addition to the ability of c-mpl ligand to support megakaryocytic development from CD34+ precursor cells, several lines of evidence also point to a stimulatory effect on hematopoietic stem cells. When recombinant thrombopoietin or pegylated megakaryocyte growth and development factor is administered to normal animals or humans, there is a dose-dependent increase in the platelet count. When administered following chemotherapy in animal models or humans, c-mpl ligands reduce the duration and sometimes the degree of thrombocytopenia. The issue of whether clinically relevant thrombocytopenia can be ameliorated has so far been more difficult to resolve. Because severe thrombocytopenia is not commonly seen with standard chemotherapy regimens, clinical studies examining c-mpl ligands for their ability to ameliorate chemotherapy-induced thrombocytopenia will focus on treatment of acute leukemias and bone marrow transplantation. The potential utility of c-mpl ligands for treatment of myelodysplastic syndromes, aplastic anemias, or in HIV infection, will have to be evaluated in the future. Possibly the greatest potential of thrombopoietic growth factors in the near future may be in transfusion medicine, to collect and to store platelets from healthy donors or in autologous settings.
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PMID:Megakaryocytic growth factors: is there a new approach for management of thrombocytopenia in patients with malignancies? 1004 50

Mastocytosis is a heterogeneous group of disorders characterized by abnormal growth and accumulation of mast cells in skin, bone marrow, bone, gastrointestinal tract, liver, spleen and lymph nodes. Today, regarding its biological features, mastocytosis (with or without myeloid accompanying disorders) is considered to be a hematologic disease. The classification proposed by Metcalfe in 1991 is the most useful in caring for patients with mastocytosis. In this classification 4 groups are described: 1) indolent mastocytosis with or without extracutaneous involvement; 2) systemic mastocytosis with an associated hematologic disorder; 3) aggressive mastocytosis; 4) mast-cell leukemia. Cutaneous mastocytosis typically presents as urticaria pigmentosa or diffuse cutaneous mastocytosis and these patients usually have a benign course. On the contrary, systemic mastocytosis is a disease with an increased risk to develop an aggressive hematologic disorder. In these patients a second hematologic process, such as myeloproliferative or myelodysplastic syndrome or acute leukemia, may occur. These patients often present without skin involvement and they have a very poor prognosis. Mast cell is a medium-sized granulated cell releasing chemical mediators (histamine, heparin, protease and cytokines). Mast cells originate from pluripotent hemopoietic progenitor cells that express the CD34 antigen. Mast cells are present in the bone marrow and are distributed throughout the connective tissues. Recently a mast-cell growth factor (MGF) has been identified. Clinical symptoms occur from the release of chemical mediators and the pathologic infiltration of cells. Although no effective therapy for patients with Mastocytosis is known, some patients may benefit from corticosteroid and interferon alpha treatment. The present article gives an overview of current knowledge about the biology, heterogeneity and treatment of human mastocytosis.
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PMID:[Systemic mastocytosis. A review of current diagnostic and therapeutic approaches]. 1022 58

C-mpl ligand acts primarily as a lineage-specific hematopoietic growth factor by promoting proliferation of megakaryocyte precursors and their differentiation into megakaryocytes and platelets. In addition to the ability of c-mpl ligand to support megakaryocytic development from CD34+ precursor cells, several lines of evidence also point to a stimulatory effect on hematopoietic stem cells. When recombinant thrombopoietin or pegylated megakaryocyte growth and development factor is administered to normal animals or humans, there is a dose-dependent increase in the platelet count. When administered following chemotherapy in animal models or humans, c-mpl ligands reduce the duration and sometimes the degree of thrombocytopenia. The issue of whether clinically relevant thrombocytopenia can be ameliorated has so far been more difficult to resolve. Because severe thrombocytopenia is not commonly seen with standard chemotherapy regimens, clinical studies examining c-mpl ligands for their ability to ameliorate chemotherapy-induced thrombocytopenia will focus on treatment of acute leukemias and bone marrow transplantation. The potential utility of c-mpl ligands for treatment of myelodysplastic syndromes, aplastic anemias, or in HIV infection, will have to be evaluated in the future. Possibly the greatest potential of thrombopoietic growth factors in the near future may be in transfusion medicine, to collect and to store platelets from healthy donors or in autologous settings.
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PMID:Memorial lecture. Megakaryocytic growth factors: is there a new approach for management of thrombocytopenia in patients with malignancies? 1023 62

The myelodysplastic syndrome (MDS) remains challenging to the clinician in terms of diagnosis and management. The diagnosis is essentially one of exclusion in first ruling out other disorders that can also cause peripheral blood/bone marrow cell dysplasia and cytopenias. The distinguishing biological characteristic of MDS is that it is a clonal disorder of the marrow with impaired differentiation. Recent studies implicate extensive apoptosis as the explanation of the paradoxical observation of marrow hyperplasia but peripheral blood cytopenia. Neutropenia and/or neutrophil dysfunction account for the primary clinical manifestation of MDS in terms of an increased risk for infection, which is the leading cause of death in MDS. The clonal nature of MDS places it also at continual risk for transformation to acute leukemia. Predicting overall survival as well as the risk of AML transformation has been improved by the recent development of a scoring system (International Prognostic Scoring System) that incorporates three laboratory variables: percent of marrow blasts, degree of cytopenias, and presence of chromosomal abnormalities. Based on these variables, four prognostic subgroups can be delineated ranging from low risk with a median survival of 5.7 years, to high risk with a median survival of 0.4 years. Management of MDS can now be based on the patient's respective prognostic subgrouping, with low-risk patients being considered for hematopoietic growth factor singly or in combination if at the point of red cell transfusion dependence and/or neutropenia with recurrent infections, while high-risk patients should be offered AML-induction therapy or novel agents such as topotecan. One must individualize further in patients in the remaining intermediate groups, I and II, in choosing the most appropriate therapy. Future advances upon understanding the molecular details of the MDS clone should ultimately improve the care of patients with MDS.
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PMID:Understanding the Myelodysplastic Syndromes. 1038 74

Interleukin (IL)-3 is a multipotent hematopoietic growth factor produced by activated T cells, monocytes/macrophages and stroma cells. The human IL-3 gene is located on chromosome 5 near segment 5q31. The high-affinity receptor for human IL-3 is composed of alpha and beta subunits. IL-3 shares a common beta subunit with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-5; this subunit has been mapped to chromosome 22q13.1. The biological effects of IL-3 have been studied in human and murine hematopoietic cell lines and normal human marrow cells. Addition of IL-3 to the culture medium induces proliferation, maturation and probably self-renewal of pluripotent hematopoietic stem cells and cells of myeloid, erythroid and megakaryocytic lineages. Human IL-3 was cloned in 1986, and since then various clinical trials have assessed the in vivo potential of recombinant human (rhIL-3). Initial results of phase I/II studies of IL-3 at a dose of 5-10 microg/kg subcutaneously daily for 5-10 days in patients with relapsed lymphomas, small-cell lung cancer, breast cancer and ovarian cancer showed that post-chemotherapy application of IL-3 reduces chemotherapy delays and induces faster regeneration of granulocytes and platelets. However, these results were not confirmed in phase III studies. The role of IL-3 alone in the treatment of myelodysplastic syndromes (MDS), aplastic anemia (AA) and other bone marrow failure disorders have also been disappointing. However, preliminary studies of IL-3 in combination with chemotherapeutic agents and immunosuppression have demonstrated encouraging results in patients with MDS and AA respectively. The therapeutic potential of IL-3 in peripheral blood stem cell (PBSC) harvesting and priming of stem cells before harvest is beginning to be identified. Initial results of IL-3 combination with GM-CSF or later-acting growth factors such as granulocyte colony-stimulating factor (G-CSF) have yielded larger amounts of PBSC during harvesting. In recent years, the availability of synthetic IL-3 receptor (IL-3R) agonists and similar chimeric molecules with greater in vitro biological activity and fewer inflammatory side-effects has extended our options to employ and compare these molecules and rhIL-3 for the prevention of chemotherapy-induced myelosuppression. The role of IL-3 and IL-3R agonists in ex vivo expansion of stem cells, dendritic cell development and gene transfer requires further evaluation. It appears that future application of IL-3 in combination with other cytokines is an attractive way forward in the prevention of treatment-related mortality and morbidity in oncology patients. It also shows prospects for the development of new therapeutic strategies for dose escalation and immune modulation for cancer patients with relapsed and resistant disease.
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PMID:Interleukin-3 in hematology and oncology: current state of knowledge and future directions. 1051 81


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