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)

Characteristic of Philadelphia (Ph)+ chronic myelogenous leukemia (CML) is the presence of the chimeric BCR/ABL (p210) protein possessing elevated protein tyrosine kinase activity relative to the normal c-abl tyrosine kinase. Our previous studies demonstrated subtle differences in the growth, phenotypic and morphologic characteristics of the most primitive subpopulations of primary lin-Ph+ chronic phase CML blasts and comparable primary lin- normal blasts. Recently, in comparing proteins phosphorylated on tyrosine in these cell populations, we reported a prominent 62 kDa phosphotyrosyl (P-tyr) protein constitutively present in primary primitive lin- CML chronic phase blasts which was virtually undetectable in primary primitive lin- normal blasts. In the present studies, we demonstrate that this P-tyr p62 from primary primitive lin- chronic phase CML blasts co-immunoprecipitates with ras-GAP. Furthermore, in addition to the p210 protein, we show in whole cell lysates the presence of other clearly consistent but less prominent P-tyr proteins with molecular weights of approximately 155, 140, 110, 55 and 45 kDa as well as more minor P-tyr proteins of approximately 190, 85, 52, 42 and 39 kDa constitutively present in primary primitive lin- chronic phase CML blasts. In analyzing proteins tyrosine phosphorylated in primary primitive lin- normal blasts in response to various hematopoietic growth factors, we found a striking similarity in the phosphorylation of four major (approximately 140, 110, 62 and 56 kDa) and three minor (approximately 51, 45 and 42 kDa) P-tyr proteins after stimulation with c-kit ligand and the P-tyr proteins constitutively phosphorylated in primary primitive lin- chronic phase CML blasts. Other growth factors tested (ie GM-CSF, G-CSF, IL-3, FLT3 ligand and EPO) were much less active or stimulated phosphorylation of other proteins. It is provocative that at least seven proteins rapidly and transiently phosphorylated on tyrosine in the c-kit ligand signal transduction pathway in lin- normal blasts may be constitutive substrates for the p210 activated tyrosine kinase in comparable lin- chronic phase CML blasts. In addition, it is intriguing that some of the biological effects on hematopoietic progenitors attributed to the c-kit ligand may be similar to some of the observed biological consequences of the p210 protein, including survival and expansion of a more mature stem cell population, probably at the time of lineage commitment rather than at the level of the earliest self-renewing stem cell.
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PMID:c-kit ligand stimulates tyrosine phosphorylation of a similar pattern of phosphotyrosyl proteins in primary primitive normal hematopoietic progenitors that are constitutively phosphorylated in comparable primitive progenitors in chronic phase chronic myelogenous leukemia. 863 31

Using chronic myelogenous leukemia (CML) as a model, we tested the hypothesis that cytokine-independent growth of leukemia cells results from aberrant activation of cytokine signaling pathways. The STAT5 (signal transducer and activator of transcription) protein, which is activated transiently in normal myeloid cells by cytokines such as GM-CSF (granulocyte-macrophage colony stimulating factor), was constitutively activated in cell lines derived from CML patients, even in the absence of GM-CSF. STAT5 was also activated in primary mouse bone marrow cells acutely transformed by the CML-specific BCR-ABL oncogene, but not by the serine kinase oncogene v-MOS. Reconstitution experiments in non-hematopoietic cells show that STAT5 activation by BCR-ABL occurs independent of cytokines. Results using BCR-ABL mutants which specifically uncouple connections to known signal transduction pathways show that STAT5 activation is kinase dependent and correlates directly with ability to confer cytokine independent growth in hematopoietic cells. BCR-ABL also activates JAK kinases, which may provide a mechanism for STAT activation. These findings are consistent with a role for STAT5 in hematopoietic transformation by BCR-ABL.
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PMID:Constitutive activation of STAT5 by the BCR-ABL oncogene in chronic myelogenous leukemia. 871 Mar 63

Twenty-five patients with hematologic malignancies were treated with busulfan (16 mg/kg) and cyclophosphamide (50 mg/kg x 3 days) as conditioning for bone marrow transplantation using marrow from serologically matched, DR locus genotypically identical unrelated donors. Previous studies of BuCy2 as conditioning for UD-BMT have reported a graft failure rate of up to 21% suggesting it may be insufficiently immunosuppressive in this setting. We elected not to use BuCy4 as it may have a higher incidence of extramedullary toxicity. In addition the patients received GM-CSF (500 mg/m2) from day 0, cyclosporine and short-course methotrexate (15 mg/m2 x 1, then 10 mg/m2 x 3) as GVHD prophylaxis and prophylactic ganciclovir at engraftment if either they or their donor were CMV antibody positive. The median age of the 25 patients was 41 years and the most common diagnosis was CML (76%). Seven patients were considered poor risk and eight males were recipients of marrow from female donors. Sixteen patients survive at a median of 435 days from transplant. The actuarial overall and disease-free survivals at 1 year in this group of older patients were 62 +/- 20% and 57 +/- 20% and 100-day survival was 70%. The engraftment rate was 100%; there have been no instances of secondary graft failure. Fifteen patients (60%) developed grade II-IV GVHD and 12 of 16 (75%) developed some chronic GVHD but only half of these were extensive. The performance status of survivors is good (median of 90); seven of 12 eligible patients are back at work. This study demonstrates that UD-BMT can be successfully performed in very closely HLA-matched older patients using a chemotherapy-only protocol and that low rates of severe acute GVHD can be achieved without T cell depletion.
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PMID:Unrelated donor bone marrow transplantation without T cell depletion using a chemotherapy only condition regimen. Low incidence of failed engraftment and severe acute GVHD. 872 53

The adenine nucleoside analogue, fludarabine phosphate, in combination with cytosine-arabinoside (Ara-C) and granulocyte-colony stimulating factor (G-CSF) (the so called FLAG regimen) has recently been shown to be effective in the treatment of poor-prognosis acute non-lymphoid leukaemia. We used this combination plus novantrone (FLANG regimen) in a case of Ph1+ chronic myeloid leukaemia (CML) unresponsive to interferon alpha that had progressed to an acute phase, after 3 months of treatment with 6-mercaptopurine and hydroxyurea. The patient was treated with two courses of fludarabine 30 mg/m2 (days 1-5) + Ara-C 2 g/m2 (days 1-5) + novantrone 5 mg/m2 (days 1-3) and G-CSF from day 0 to neutrophil recovery. After the first cycle of chemotherapy, bone marrow blasts decreased from 100% to less than 5% (clinical complete remission), with a progressive clearance of Ph1+ metaphases (from 100% to 12%). At the end of the second course, a progressive increase of blasts was observed again and karyotypic detection of Ph+ cells was also documented (from 12% to 42.9%). During this partial remission, the patient underwent an allogeneic bone marrow transplantation from an HLA matched identical brother. At the time of this report, he is still alive and well and in complete karyotypic remission. This partial therapeutic success was compared with the result obtained in another previously reported CML case: differences in the therapeutic efficacy of protocols employing fludarabine nucleosides and the type of blastic cells involved are discussed.
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PMID:FLANG (fludarabine + cytosine arabinoside + novantrone + G-CSF) induces partial remission in lymphoid blast transformation of Ph+chronic myelogenous leukaemia. 872 45

Cell adhesion to the extracellular matrix is largely mediated by adhesion molecules of the integrin family and is often diminished upon oncogenic transformation. However, we show here that the chronic myelogenous leukemia oncogene Bcr/Abl has positive effects on VLA-4 and VLA-5 integrin function. The presence of Bcr/Abl in the GM-CSF- or IL-3-dependent hematopoietic cell lines MO7e, 32D, and BaF/3 enhanced cell binding to both soluble and immobilized fibronectin. The effect was due to enhanced function of the VLA-5 integrin fibronectin receptor and not to increased surface expression. In parallel, Bcr/Abl stimulated cell adhesion to the VLA-4 integrin ligand VCAM-1. Stimulation of VLA-5 function directly correlated with induction of Bcr/Abl tyrosine kinase activity in a temperature-sensitive kinase mutant. Thus, Bcr/Abl stimulates integrin-dependent cell adhesion, by a mechanism involving increased ligand binding, with the tyrosine kinase activity of Bcr/Abl likely playing a key role. Consistent with these results, hematopoietic precursor cells from chronic myelogenous leukemia patients also showed increased adhesion to fibronectin.
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PMID:Bcr/Abl expression stimulates integrin function in hematopoietic cell lines. 875 65

A 29-year-old woman underwent a T cell-depleted unrelated donor transplant for CML in chronic phase. Sixty-three days after marrow infusion, the patient developed fevers and generalized lymphadenopathy. Lymph node biopsy was consistent with monoclonal EBV-associated immunoblastic lymphoma for which the patient received 10(5) CD3-positive donor leukocytes per kilogram. Six days after leukocyte infusion the patient developed mental status changes without focal neurological deficit. MRI revealed no mass lesions. Cerebral spinal fluid revealed a white blood cell count of 1650 cells/mm3 which were shown to be T lymphocytes of donor origin. The CSF was tested and found to be PCR positive for EBV virus interval repeat 1 sequence (IR1). The lymphocytosis and mental status changes resolved without specific intervention. Subsequently she developed marrow aplasia, which was believed to be secondary to the infusion of donor leukocytes. Possible mechanisms for these two previously unreported side-effects of donor leukocyte infusion are discussed.
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PMID:Lymphocytosis of donor origin in cerebrospinal fluid, and marrow aplasia after donor leukocyte infusion for EBV-lymphoproliferative disease. 883 21

The growth factor of hematopoiesis, G-CSF and GM-CSF, are now extremely useful in stem cell transplantation (SCT). Their main indications are given in this short paper. They accelerate hematopoietic recovery and they reduce morbidity and mortality after autologous SCT. GM-CSF can protect from hematopoietic toxicity of Gancyclovir and can reduce the mortality related to autologous and allogeneic graft failure. The combination of GM-CSF, G-CSF and erythropoietin can replace autologous SCT after a high dose therapy. G and GM-CSF are used to mobilise peripheral stem cells and allow peripheral blood stem cell transplantation. G-CSF given after a chemotherapy is able to mobilise Philadelphia negative stem cells in chronic myelocytic leukemia patients. Finally allogeneic peripheral blood stem cell mobilised by G-CSF in healthy donor is now a new field of clinical trials.
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PMID:[Contribution of hematopoietic growth factors and especially in the context of grafts of hematopoietic stem cells]. 888 Nov 2

Successful allogeneic peripheral blood progenitor cell (PBPC) transplantation has recently been reported by several transplant centers. This is a first report describing allogeneic PBPC transplantation in five patients using related pediatric donors between the ages of 4 and 13 years. Donors underwent 3 or 4 days of rhG-CSF treatment (6 micrograms/kg q 12 h) for stem cell peripheralization prior to PBPC collection, which was performed by continuous-flow apheresis on day 4 or 5. Venous access was exclusively by ante-cubital veins. A median of 2.2 times (range 1.4-3.6) the donor's total blood volume (TBV) was processed per procedure. In cases where the donor's TBV was < 2 liters, the blood cell separator was primed with human serum albumin (HSA-5%), and anticoagulation was performed using a combination of heparin (pre-apheresis bolus + continuous infusion (CI)) and/or ACD-A (CI at a reduced rate). The median number of CD34+ cells collected per kg of donor body weight (b.w.) and per liter of donor blood processed during each procedure was 128 x 10(4) (range 58 x 10(4)-314 x 10(4)). Between one and two aphereses were sufficient to collect a safe CD34+ cell engraftment dose of 3 or 4 x 10(6)/kg of recipient b.w. Two PBPC recipients were parents, and three were siblings. After freezing and thawing, the median number of CD34+ cells per kg of recipient b.w. thawed and transfused was 8.5 x 10(6) (range 3.2 x 10(6)-9.7 x 10(6)). The time to PMN > 1000/microliters was between 10 and 16 days (four out of five evaluable patients), and platelets > 20000/microliters were reached between day 13 and 14 post-transplantation (three out of five evaluable patients). Two out of three evaluable patients developed grades one and three acute GVHD, and one out of three developed chronic GVHD. Two patients died of sepsis and VOD at day 10 and 19, respectively. Two adult patients are alive and in cytogenetic and molecular remission of CML at +339 and +227 days post-allotransplantation. One 3-year-old girl with hemophagocytic lymphohistiocytosis is in remission at +304 days post-transplantation. Using pediatric donors for allogeneic PBPC transplantation appears to be safe, yields a sufficient amount of progenitors for prompt engraftment, and results in clinical outcome similar to adult PBPC allotransplantation.
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PMID:Allogeneic peripheral blood stem cell transplantation using normal patient-related pediatric donors. 893 41

Interleukin-11 (IL-11) is a novel cytokine that has been shown to stimulate human hematopoietic progenitors including the CD34+ CD33- DR- early progenitors. IL-11 has little effect on its own but it synergizes with other hematopoietic growth factors. We investigated the recovery of human myeloid progenitors incubated with IL-11 alone or in combination with other cytokines, including stem cell factor (SCF), interleukin-3 (IL-3) and granulocyte macrophage colony-stimulating factor (GM-CSF) following their in vitro treatment with ARA-C (10(-9) M) or Eilatin (10(-7) M). IL-11 in combination with IL-3 and GM-CSF markedly increased CFU-C colony growth pre- and post-ARA-C or Eilatin incubation from CML and normal individual bone marrow (BM) cells. Similarly, IL-11 alone or in combination with other cytokines increased cell recovery following 7-day suspension culture. A decrease in BCR/ABL fusion product was observed (by FISH analysis) after incubation of BM cells from CML patients in liquid culture for 7 days with 10(-9) M ARA-C or 10(-7) M Eilatin in the presence of IL-11 alone or in combination with other cytokines. These results indicate that following cytoreductive therapy IL-11 may enhance to a greater extent the growth of normal myeloid progenitors than the malignant clone and may, therefore, be of clinical importance for CML patients treated with chemotherapeutic agents.
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PMID:Synergistic effects of interleukin-11 with other growth factors on the expansion of hematopoietic progenitors from normal individuals and chronic myeloid leukemia patients resistant to treatment with cytosine arabinoside or eilatin. 894 85

Juvenile chronic myelogenous leukemia (JCML) is a hematologic malignancy of monocyte-macrophage lineage in which leukemic progression is mediated in an autocrine manner by tumor necrosis factor (TNF-alpha), GM-CSF and possibly other growth factors. Cytogenetic data showing involvement of both erythroid and monocyte-macrophage lineages in the JCML leukemic clone, as well as an observed episode of B-lineage lymphoid blast crisis in JCML, has strengthened the thesis for a lympho-hematopoietic pluripotent stem cell origin for the disorder. To study this further, JCML CD34+ cells from bone marrow (BM) or spleen from six newly diagnosed patients were isolated and cultured in clonogenic assays with combinations of recombinant cytokines. Compared to control CD34+ cells, JCML cells from all patients showed an aberrant growth pattern restricted almost exclusively to the monocyte-macrophage lineage. Most of the clonogenic activity was seen in a subsorted population of CD34+, HLA-Dr- cells. Additionally, an exaggerated growth response to minute doses of GM-CSF that had no effect on control cells was observed with JCML CD34+ cells. Recloning ("self-renewal") of JCML CD34+ cells was also strongly promoted by GM-CSF. JCML colonies also formed spontaneously in the absence of exogenous cytokines but were augmented by GM-CSF, interleukin 1 and TNF-alpha, the latter feature not seen with control CD34+ cells from normal BM. The abnormal spontaneous growth pattern of CD34+ JCML cells could be suppressed directly in vitro by anti-TNF-alpha antibodies and anti-GM-CSF antibodies alone or in combination, and by soluble TNF-alpha receptors (sTNF-R:Fc), consistent with the notion that JCML CD34+ cells are stimulated by both cytokines in an autocrine manner. In malignant CD34+ cells from one patient, the cytogenetic marker monosomy 7 proved leukemic involvement of monocyte-macrophage, erythroid and B-lymphoid lineages. We conclude that CD34+ JCML cells of multilineage potential exhibit excessive and aberrant monocyte-macrophage colony formation, a property that was previously observed in JCML progenitors found in light density cell fractions. Thus, within the CD34+ cellular compartment is a subpopulation of JCML "stem" cells that accounts for the abnormal leukemic proliferative activity in this disease.
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PMID:Juvenile chronic myelogenous leukemia multilineage CD34+ cells: aberrant growth and differentiation properties. 894 26


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