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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors describe a coherent model for differentiated leukemias derived from physiopathological studies on Friend leukemia. In Friend leukemia, Friend virus induces permanent differentiation of erythropoietin-responsive cells. This erythropoietic proliferation and maturation is accompanied by a marked cell loss and provokes enlargement of the stem cell compartment. The so-called leukemic cells have a limited proliferation capacity and may not be truly malignant as opposed to blastic cells in acute leukemias. Clinical, hematological, and physiopathological data that are presently available in chronic granulocytic leukemia, polycythemia vera, and the erythroblastic component of erythroleukemia are compatible with the Friend physiopathological model. It is suggested that these differentiated leukemias initiate from an uncontrolled differentiation of a committed cell compartment, which stimulates proliferation of the stem cell compartment. The disease would be due to a proliferation and accumulation of "subnormal" cells characterized by a shorter mean life-span than the normal differentiated cell population. Although limited, the data available suggest that the physiopathology of acute leukemias is clearly distinguishable from that of differentiated leukemias; several immunological and therapeutic applications of this model are outlined.
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PMID:Physiopathology of human and virus-induced murine leukemias. 17 21

Serum of patients suffering from a chronic myeloproliferative disorder (polycythaemia, era, osteomyelofibrosis, chronic myeloid leukaemia) and serum of lethally irradiated rats injected before application of a single doses of erythropoietin did not enhance the effect of erythropoietin -- measured with the iron incorporation rate of polycythemic mice. The rationale for these experiments is to try to find a "myeloproliferative factor", which augments the number of stem cells as described in sera of patients with polycythaemia vera, osteomyelofibrosis, and lethally irradiated mice.
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PMID:[On the existence of a myeloproliferative factor in patients with a myeloproliferative syndrome (author's transl)]. 28 27

The ability of cells derived from the K562 cell line to generate erythropoietic colonies was studied. The K562 cell line was derived from a patient with chronic myelogenous leukemia 8 yr ago by Lozzio and Lozzio. Rare benzidine-positive colonies formed when these cells were cloned in plasma clots (3 +/- 1/10(4) cells), and their number was not substantially increased by the addition of erythropoietin (9.5 +/- 1/10(4) cells). Sodium butyrate was capable of markedly enhancing the number of benzidine-positive colonies (19.5 +/- 1/10(4) cells) formed, while the combination of sodium butyrate plus erythropoietin exerted a synergistic effect on erythropoietic colony formation (57 +/- 4/10(4) cells). The K562 cell line is a long-term culture system that contains human erythropoietic stem cells. This cell line should be useful in future studies on the cellular and molecular events associated with human erythroid cell differentiation.
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PMID:Induction of erythropoietic colonies in a human chronic myelogenous leukemia cell line. 29 42

Peripheral blood and bone marrow specimens from 6 patients with Ph1-positive CML were evaluated for their content of erythropoietic and granulopoietic colony-forming progenitor cells. Specimens obtained from untreated patients showed marked increases in all compartments the most dramatic of which were for CFU-E and circulating CFU-C. This increased cell flow down the early stages of the red cell pathway in CML suggests that heightened proliferation and differentiation of primitive hemopoietic cells may be a more general phenomenon than previously suspected in this disease. In 5 of 6 patients, abnormal erythroid progenitors capable of proliferation and differentiation into hemoglobinized erythroblasts in cultures containing less than 0.002 units of erythropoietin/ml were regularly detected. In the 6th patient abnormal growth was not seen in cultures of the initial marrow obtained but was detected in cultures set up with peripheral blood taken 7 months later. The unexplained amplification of the erythropoietic compartment and the ability of some of these cells to mature in vitro in the virtual absence of erythropoietin is at variance with the anemia characteristic of untreated patients. This suggests the possibility of a major differentiation block at the level of CFU-E. Further studies of the properties of erythroid progenitors in these patients should help to provide new insights into the pathogenesis of CML and may provide useful markers for monitoring engrafted cell function after autotransplantation of patients in blast crisis.
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PMID:Abnormalities in the erythroid progenitor compartments in patients with chronic myelogenous leukemia (CML). 29 48

Proliferating populations of neutrophils, monocytes, eosinophils, erythroid cells, and T-lymphocytes from normal subjects or patients with various diseases can now be analysed by colony formation in semisolid cultures. These cultures accurately determine the number and proliferative activity of the precursor cells of each population and can also be used to monitor the levels of specific regulatory factors (for example, erythropoietin, colony-stimulating factor) in the serum or urine of such patients. Studies using semisolid cultures have shown that the leukemic cells in chronic and acute myeloid leukemia remain dependent on the normal regulator, granulocyte-macrophage colony-stimulating factor, for proliferation. The cultures have proved valuable in the prognostic assessment of acute leukemic patients and in monitoring impending changes in the clinical status of patients with acute or chronic myeloid leukemia or myeloproliferative disorders.
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PMID:In-vitro cloning techniques for hemopoietic cells: clinical applications. 33 9

The role of the KIT protooncogene in human hematopoiesis is uncertain. Therefore, we examined KIT mRNA expression in normal human bone marrow mononuclear cells (MNC) and used antisense oligodeoxynucleotides (oligomers) to disrupt KIT function. KIT mRNA was detected with certainty only in growth factor-stimulated MNC. Expression was essentially abrogated by making MNC quiescent or by inhibiting myb gene function. Oligomers blocked KIT mRNA expression in a dose-response and sequence-specific manner, thereby allowing functional examination of the KIT receptor. In experiments with either partially purified or CD34(+)-enriched MNC, neither granulocyte nor megakaryocyte colony formation was inhibited by oligomer exposure. In contrast, KIT antisense oligomers inhibited interleukin 3/erythropoietin-driven erythroid colony formation approximately 70% and "stem cell factor"/erythropoietin-driven colony formation 100%. The presence of erythroid progenitor cell subsets with differential requirements for KIT function is therefore suggested. Growth of hematopoietic colonies from chronic myeloid leukemia and polycythemia vera patients was also inhibited, while acute leukemia colony growth appeared less sensitive to KIT deprivation. These results suggest that KIT plays a predominant role in normal erythropoiesis but may be important in regulating some types of malignant hematopoietic cell growth as well. They also suggest that KIT expression is linked to cell metabolic activity and that its expression may be regulated by or coregulated with MYB.
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PMID:Role of the KIT protooncogene in normal and malignant human hematopoiesis. 137 82

Bone marrow transplantation was performed on a 15 year old girl with chronic myelogenous leukemia. The bone marrow was obtained from her younger sister, who was human leukocyte antigen haplo-identical but major ABO incompatible. As a result, the condition of pure red cell aplasia (PRCA) persisted over a long period of time. In order to overcome major ABO incompatibility, erythrocytes were eliminated from the bone marrow graft before transplantation, and methotrexate and cyclosporine (CsA) were used to prevent graft-versus-host disease (GVHD). Administration of erythropoietin proved ineffective. B19 parvovirus infection could not be detected during that time. Agglutinin titers decreased to less than fourfold in parallel with the recovery of erythrocytes. Reports on similar PRCA have been limited to cases of transplantation with ABO incompatibility and cases where CsA was administered to prevent GVHD. This suggests that ABO incompatibility and CsA might be related to the development of PRCA.
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PMID:Long duration of erythrocyte hypoplasia after bone marrow transplantation. 141 39

Serum erythropoietin (Epo) titers in patients with various hematological malignancies and related diseases were determined by radioimmunoassay. Serum Epo titer was inversely correlated with hemoglobin concentration in iron deficiency anemia, aplastic anemia, myelodysplastic syndromes (MDS), acute leukemia, malignant lymphoma, multiple myeloma and myelofibrosis, but there was no correlation between serum Epo titer and hemoglobin concentration in chronic myelogenous leukemia or polycythemias. Serum Epo titers in aplastic anemia were much higher than those in iron deficiency anemia. Serum Epo titers in MDS, malignant lymphoma and multiple myeloma differed considerably among patients. Serum Epo titers in untreated polycythemia vera were significantly lower than in treated polycythemia vera or secondary polycythemia.
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PMID:Serum erythropoietin titers in hematological malignancies and related diseases. 146 Mar 22

Twenty-eight allogeneic BMT patients (16 with acute leukemia, 12 with chronic myeloid leukemia) were included in a single center, prospective, randomized, controlled trial to assess the value of recombinant human erythropoietin (rh-Epo) in this setting. rh-Epo was administered through a central venous catheter as a single bolus injection (days 0-7: 100 U/kg/d; days 7-30: 150 U/kg/d). No secondary effects to rh-Epo treatment were detected. An earlier appearance of reticulocytes and a diminished need of red blood cells (RBCs) transfusions were observed in patients who were treated with rh-Epo (4 units vs 12 units; p < 0.05). The time to unsupported platelets above 25 x 10(9)/l was less in patients treated with rh-Epo than in control patients (19 days vs 31; p < 0.05), and they received significantly fewer platelet transfusions (36 units vs 138.5; p < 0.05). Our results show that rh-Epo treatment is capable of accelerating the erythroid reconstitution and decreasing the need for RBC transfusions. A beneficial effect on platelet reconstitution is also suggested, but further studies are necessary to confirm this point.
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PMID:Erythropoietin treatment in allogeneic BMT accelerates erythroid reconstitution: results of a prospective controlled randomized trial. 149 Feb 3

Mast cell growth factor (MGF), the ligand for the c-kit receptor, has been shown to be a hematopoietic growth factor that preferentially stimulates the proliferation of immature hematopoietic progenitor cells (HPC). We studied the effect of MGF on the in vitro growth of clonogenic leukemic precursor cells in the presence or absence of interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and/or erythropoietin (EPO). Leukemic blood and bone marrow cells from patients with various types of acute myeloid leukemia (AML), chronic myeloid leukemia (CML) in chronic phase, as well as bone marrow samples from patients with myelodysplastic syndromes (MDS) were studied. MGF as a single factor did not induce significant colony formation by clonogenic leukemic precursor cells. In the presence of IL-3 and/or GM-CSF, MGF weakly stimulated the colony formation by clonogenic precursor cells from patients with AML. In contrast, in the presence of IL-3 and/or GM-CSF, MGF strongly induced both size and number of leukemic colonies from patients with CML in chronic phase. Furthermore, in the presence of EPO, MGF strongly stimulated erythroid colony formation by CML precursor cells. Cytogenetic analysis of the colonies showed that all metaphases after 1 week of culture were derived from the leukemic clone. In patients with MDS, MGF strongly stimulated myeloid colony formation in the presence of IL-3 and/or GM-CSF (up to fourfold), and erythroid colony formation in the presence of EPO (up to eightfold). Not only the number, but also the size of the colonies increased. In the presence of MGF, the percentage of normal metaphases increased in three patients tested after 1 week of culture compared with the initial suspension, suggesting that the normal HPC were preferentially stimulated compared with the preleukemic precursor cells. In the absence of exogenous EPO and in the presence of 10% human AB serum, MGF in the presence of IL-3 and/or GM-CSF induced erythroid colony formation from normal bone marrow and patients with MDS or CML, illustrating that MGF greatly diminished the EPO requirement for erythroid differentiation. These results indicate that MGF may be a candidate as a hematopoietic growth factor to stimulate normal hematopoiesis in patients with acute myeloid leukemia, or with myelodysplastic syndromes.
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PMID:Effect of mast cell growth factor (c-kit ligand) on clonogenic leukemic precursor cells. 163 26


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