Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Children with Philadelphia chromosome (Ph+) acute lymphoblastic leukemia (ALL) have a poorer prognosis than do most pediatric patients with ALL. Because of this poor prognosis and the presence of the Ph chromosome, we have asked whether or not Ph + ALL involves a multipotential stem cell. We cultured hematopoietic progenitors from two children with Ph+ ALL and examined individual BFU-E and CFU-GM colonies for the Ph chromosome. We studied cells from two patients after 18 to 34 months of first complete clinical remission; direct cytogenetic analyses showed 26% and 13% Ph+ metaphases in these patients' marrow cells. BFU-E colonies were obtained from light density marrow cells cultured in methylcellulose supplemented with erythropoietin and CFU-GM colonies from agar or methylcellulose cultures stimulated with leukocyte feeder layers. Fifty-seven G-banded metaphases were recovered from 33 colonies. Ten metaphases from seven colonies were Ph+. Ph+ metaphases were found in three of 12 and three of five BFU-E colonies from the two patients. One of 16 CFU-GM colonies from one patient had the Ph+ chromosome; analyzable metaphases were not obtained from CFU-GM of the other patient. No colonies contained both Ph+ and Ph- cells. These results indicate that Ph+ ALL with persistence of Ph+ cells in remission involves a multipotential stem cell for erythroid and granulocyte/macrophage as well as lymphoid lineages. Multipotential stem cell involvement in the pathogenesis of some childhood Ph+ ALL suggests similarities to Ph+ chronic myelocytic leukemia and may contribute to the poor prognosis of these patients.
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PMID:Evidence for a multipotential stem cell disease in some childhood Philadelphia chromosome-positive acute lymphoblastic leukemia. 347

We investigated the influence of T-cell depletion on BFU-E and CFU-GM colony growth in vitro from normal individuals and patients with chronic granulocytic leukemia (CGL), idiopathic myelofibrosis (MF), and polycythemia vera (PV). Preincubation of mononuclear cells with the complement-fixing monoclonal antibody OKT11A, which is cytotoxic to T-lymphocytes, significantly reduced the number of erythropoietin (epo)-dependent BFU-E colonies cultured from normal bone marrow and normal peripheral blood, as well as from the blood of patients with CGL, PV, and MF. In contrast, the numbers of epo-independent ("endogenous") BFU-E colonies cultured from the blood of PV and MF patients were the same before and after T-cell depletion. The blood and marrow of CGL patients and normal individuals produced no epo-independent BFU-E proliferation. The growth of day-7 and day-14 CFU-GM was not significantly influenced by T-cell depletion in the majority of experiments. We conclude that T cells promote the growth of epo-dependent BFU-E colonies in vitro, but they do not influence the growth of "endogenous" BFU-E colonies from patients with myeloproliferative disorders.
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PMID:Endogenous erythroid colony formation in myeloproliferative diseases does not depend on T cells. 348 53

Erythroid colonies from five patients with an early erythroblastic leukemia were obtained in "serum-free" cultures in the presence or absence of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) and homogeneous native erythropoietin (Epo). Erythroid colonies with abnormal morphology and karyotype could be grown in different culture conditions. Their erythroid nature was ascertained by the presence of carbonic anhydrase I and glycophorin A. Leukemic erythroid progenitors strongly differed from normal progenitors in that spontaneous colonies were always obtained, sometimes with an extremely high plating efficiency (up to 5.7%). Colonies were found to be autonomous from exogenous hematopoietic growth factors because they were still obtained with a high plating efficiency at an average of one cell per culture in the absence of any added growth factor. No evidence for an autocrine secretion of Epo or GM-CSF emerged because Epo or GM-CSF could not be detected by biologic or radioimmunologic assays from the culture supernatant or cellular extracts of the leukemic cells and that Epo or GM-CSF antibodies did not block autonomous growth. In all cases, however, hematopoietic growth factors increased the plating efficiency of the abnormal erythroid progenitors. In the two "de novo" leukemias, leukemic erythroid progenitors responded primarily to Epo, whereas in the three other patients' (chronic myeloid leukemia) blast crisis they responded maximally to GM-CSF plus Epo. Recombinant erythroid-potentiating activity had no effect in any of these cases. These results suggest that the leukemic erythroid clonogenic cells arise from expansion of erythroid progenitors at different levels of differentiation (ie, CFU-E or BFU-E, depending upon the disease) and that autonomous growth is not related to a secretion of Epo or GM-CSF.
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PMID:Effects of granulocyte-macrophage colony-stimulating factor and erythropoietin on leukemic erythroid colony formation in human early erythroblastic leukemias. 349 22

A chronic myeloproliferative disorder associated with monosomy 7 is described in a 3 1/2-year-old boy. His presenting features closely resembled those of juvenile chronic myeloid leukaemia (JCML). Cytogenetic study of bone marrow cells showed that all of the metaphases examined had chromosome 7 deletions. He developed an erythroblastic phase, characterized by anaemia, marked erythroid hyperplasia of bone marrow and the appearance of nucleated red blood cells in the peripheral blood. During the erythroblastic phase, blood transfusion resulted in a suppression of erythropoiesis as evidenced in both the peripheral blood and bone marrow. The in vitro culture studies showed that the erythroid precursor was dependent upon erythropoietin (Ep) for differentiation and proliferation during the erythroblastic phase. However, the Ep dose-response curve showed that a peak of erythroid colony formation occurred at a lower concentration than in the healthy controls. These findings suggest that although the erythroid precursor remains under the control of Ep, it has an increased sensitivity to Ep during the erythroblastic phase of monosomy 7.
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PMID:Erythropoiesis during an erythroblastic phase of chronic myeloproliferative disorder associated with monosomy 7. 358 Feb 97

Peripheral blood cells from 2 patients with chronic granulocytic leukemia were separated by density centrifugation. Mononuclear cells of low density (d less than 1.062g cm-3) with blast-cell morphology were cryopreserved before culture in vitro. Upon culture in conventional colony assays, up to 20% of the cells formed hemopoietic colonies. Although the spectrum of colony types resembled that of normal bone-marrow cells, there were large differences between the patients with respect to the number, type and size of colonies that were observed. Colony formation required the addition of hemopoietic growth factors, such as colony-stimulating activity and erythropoietin to the culture medium. The cells were used to assay hemopoietic regulatory molecules. Both erythropoietin and colony-stimulating activity induced a strong proliferative response as measured by thymidine incorporation. Maximal stimulation was observed when erythropoietin and the supernatant of mixed lymphocyte cultures were added simultaneously. The difference between the cells from the 2 patients in clonal assays was reflected by the different response to individual hemopoietic regulators. The time course of maximal stimulation followed distinct patterns dependent on the source of stimulator. The stimulation was linearly dependent on the input cell number. Taken together, cryopreserved blast cells from patients with chronic granulocytic leukemia appear to be very useful for the characterization of factors regulating hemopoiesis, as well as for studies of hemopoiesis in general.
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PMID:Colony-forming cells in chronic granulocytic leukemia--I. Proliferative responses to growth factors. 387 36

Two patients with chronic myelocytic leukemia who developed an erythroblastic rather than a myeloblastic phase were studied with respect to whether or not the megaloblastic erythropoiesis was subject to normal control mechanisms. After transfusion, no significant reduction was observed in the percentage of nucleated erythroid precursors or of proerythroblasts in marrow or in blood reticulocytes. In one of the two patients, ferrokinetics and urinary erythropoietin levels were studied and were also compatible with the conclusions that erythropoiesis was autonomous in this rare syndrome. Three patients with clinical pictures compatible with Di Guglielmo's syndrome were studied as controls. As has been reported previously, erythropoiesis in this syndrome appeared to be responsive to normal control mechanisms. These data suggest that these two clinically similar syndromes, erythroblastic crisis of chronic myelocytic leukemia and Di Guglielmo's syndrome may represent qualitatively different defects in hematopoietic stem cells.
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PMID:Autonomous erythropoiesis during erythroblastic crisis of chronic myelocytic leukemia. 450 38

Early erythroid progenitors (BFUE) form colonies of mature progeny in culture. The development of hemoglobinized red cells within multilineage colonies (CFUGEMM) and erythroid bursts is dependent upon exogenously added erythropoietin and molecules released by hemopoietic subpopulations. Mixed colonies and erythroid bursts were grown from 3 patients with Ph' chronic myelogenous leukemia (CML). It was found that some mixed hemopoietic colonies and erythroid bursts did not require exogenously added erythropoietin. An increase of the plating efficiency of BFUE could be observed when erythropoietin was added. Erythroid bursts grown without added Ep from samples of the patients with chronic myelogenous leukemia have a higher probability to contain HbF than clones grown in the presence of Ep. The data support the view of a phenotypical heterogeneity among clonal descendents of a common ancestor as previously postulated for CML.
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PMID:Fetal hemoglobin analysis of erythroid bursts in patients with chronic myelogenous leukemia (CML). 619 97

Human hemopoietic pluripotent progenitors form multilineage colonies when cultured in methylcellulose with medium conditioned by leukocytes in the presence of phytohemagglutinin (PHA-LCM) and erythropoietin (EPO). We have examined their frequency, culture requirements and proliferative activity in 20 peripheral blood and 29 bone marrow specimens from patients with CML in chronic phase. Multilineage colonies developed under regular culture conditions in approximately 50% of all samples. The frequency ranged from 1-36 per 2 X 10(5) mononuclear cells of density less than 1.077 gm/ml. The requirements for PHA-LCM and EPO varied for patients with CML when compared to normal individuals; i.e., cells from some patients gave rise to mixed colonies with substantial erythroid components in the absence of PHA-LCM or without addition of the usually required EPO concentrations. The proliferative activity of CFU-GEMM was assessed using a short-term exposure to tritiated thymidine (3HTdR) prior to plating. The plating efficiency in all bone marrow and peripheral blood samples was reduced to 40-70% of the unexposed controls. In contrast, the plating efficiency after exposure to 3HTdR in normal individuals usually ranged from 70-90% of controls for bone marrow samples and from 85-100% of controls for peripheral blood samples. Thus, an increased proliferative rate of pluripotent hemopoietic progenitors is a consistent feature of CML patients. In addition, at least in some patients, different requirements for erythropoietin or PHA-LCM were observed when compared to normal culture conditions.
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PMID:Pluripotent hemopoietic progenitors (CFU-GEMM) in chronic myelogenous leukemia. 658 83

Serum erythropoietin (ESF) levels and the numbers of marrow and blood erythroid progenitors (CFU-Es) of patients with chronic myeloproliferative disorders (CMPD) were studied simultaneously. The numbers of marrow and blood CFU-Es per 1 x 10(5) cells were normal or greatly elevated. There was an inverse correlation between the hemoglobin concentration and the serum ESF level in patients with chronic myelogenous leukemia when the hemoglobin concentration ranged from 9.0 to 13.0 g/100 ml. The serum ESF level was closely related to the hemoglobin concentration in CMPD and it was suggested that the negative feedback mechanism might operate in anemic patients with CMPD.
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PMID:Serum erythropoietin (ESF) levels and erythroid progenitors (CFU-Es) of patients with chronic myeloproliferative disorders. 658 39

A patient with Ph1-positive chronic myelogenous leukemia (CML) who entered an erythroblastic transformation prior to the development of a typical myeloblastic crisis is described. In vitro methylcellulose cultures obtained at the time of erythroblastic transformation revealed that the erythroid progenitors were responsive to erythropoietin. Thus, similar to the findings in polycythemia vera, the erythroid progenitors in this case of erythroblastic transformation of CML retained responsiveness to erythropoietin in vitro.
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PMID:In vitro response to erythropoietin in erythroblastic transformation of chronic myelogenous leukemia. 693 16


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