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)

Erythropoietin-receptor (EpR) expression on bone marrow cells from normal individuals and from patients with chronic myeloid leukemia (CML) was examined by multiparameter flow cytometry after stepwise amplified immunostaining with biotin-labeled Ep, streptavidin-conjugated R-phycoerythrin, and biotinylated monoclonal anti-R-phycoerythrin. This approach allowed the detection of EpR-positive cells in all bone marrow samples studied. Most of the EpR-positive cells in normal bone marrow were found to be CD45-dull, CD34-negative, transferrin-receptor-positive and glycophorin-A-intermediate to -positive. This phenotype is characteristic of relatively mature erythroid precursors, ie, colony-forming units-erythroid and erythroblasts recognizable by classic staining procedures. Approximately 5% of normal EpR-positive cells displayed an intermediate expression of CD45, suggesting that these represented precursors of the CD45-dull EpR-positive cells. Some EpR-positive cells in chronic myeloid leukemia (CML) bone marrow had a phenotype similar to the major EpR-positive phenotype in normal bone marrow, ie, CD34-negative and CD45-dull. However, there was a disproportionate increase in the relative number of EpR-positive/CD45-intermediate cells in CML bone marrow. Even more striking differences between normal individuals and CML patients were observed when EpR-expression on CD34-positive marrow cells was analyzed. Very few EpR-positive cells were found in the CD34-positive fraction of normal bone marrow, whereas a significant fraction of the CD34-positive marrow cells from five of five CML patients expressed readily detectable EpR. These findings suggest that control of EpR expression is perturbed in the neoplastic clone of cells present in patients with CML. This may be related to the inadequate output of mature red blood cells typical of CML patients and may also be part of a more generalized perturbation in expression and/or functional integrity of other growth factor receptors on CML cells.
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PMID:Increased erythropoietin-receptor expression on CD34-positive bone marrow cells from patients with chronic myeloid leukemia. 137 Jun 38

The authors established a new hemopoietic cell line (JK-1) from a patient with chronic myelogenous leukemia in erythroid crisis. This JK-1 line predominantly consists of immature cells, but a small number of mature erythroblasts and red cells can be consistently seen without any specific differentiation inducer. The JK-1 cells grow in suspension culture supplemented with human plasma and carry double Philadelphia chromosomes. Hemoglobin staining with benzidine was positive for about 20% of cells and the type of the hemoglobin was for the most part HbF. Surface-marker analysis revealed JK-1 cells positive for glycophorin A, EP-1, and HAE9. The proportion of mature cells was elevated by the addition of delta-aminolevulinic acid. Erythropoietin (EPO) enhanced the growth of JK-1 cells either in the suspension or in methylcellulose semisolid culture. The total number of EPO receptors was 940 per cell, of which 220 sites had an affinity higher than the other 720 sites. This is the first report of an established human erythroid cell line which spontaneously undergoes terminal differentiation.
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PMID:Establishment of an erythroid cell line (JK-1) that spontaneously differentiates to red cells. 216 92

Peripheral blood and bone marrow specimens from patients with polycythemia vera (PV) and chronic myelogenous leukemia (CML) were assayed for erythroid and granulopoietic progenitor cells. All compartments were increased in CML patients in relapse although the ratio of BFU-E to CFU-C numbers remained constant in all CML patients where values ranged over several orders of magnitude. By comparison with normal ratios there was only a slight shift towards increased CFU-C numbers. No quantitative changes in any progenitor compartment was found in PV except for a marginal increase in marrow CFU-E. Erythropoietin (epo)-independent colony formation has been documented in all 61 cases of PV studied to date, and the proportion of progenitors classified as abnormal on this basis increases on average 3- to 5-fold as they differentiate in vivo from primitive BFU-E to CFU-E. Preliminary replating studies suggest that when this occurs in vitro individual BFU-E produce both normal and abnormal phenotypes. Epo-independent erythropoiesis has also been commonly observed in assays of CML cells, although its expression is more variable and in the absence of epo progenitors in CML usually make fewer erythroblasts containing even less hemoglobin than do their counterparts in PV. Expression of a common regulatory defect in erythroid cells in PV and CML suggests a possible relationship to the initial transformation event(s).
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PMID:Abnormal erythropoiesis in the myeloproliferative disorders: an analysis of underlying cellular and humoral mechanisms. 696 70

Cytokines are a class of signal peptides which represent a major communication network in living organism. Over the last decade, the discovery, cloning and purification of hematopoietic cytokines (interleukins, hematopoietic growth factors) has increased our understanding of the regulation, proliferation, differentiation and function of hematopoietic cells. More recently, the large scale production of the recombinant forms of these molecules has enabled to treat the patients with pharmacologic doses of cytokines. The therapeutic activity of interferon-alpha (IFN-alpha) has been demonstrated in patients with chronic myeloid leukaemia and other chronic myeloproliferative syndromes. IFN-gamma is useful in the prevention of infections in patients with chronic granulomatous disease. Erythropoietin (EPO) was the first hematopoietic growth factor available for clinical use, initially to treat anaemia in renal failure patients. The next cytokines introduced into the clinic were granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF). They are used successfully in haematological malignant disorders to stimulate granulopoiesis after chemotherapy or bone marrow transplantation and to help mobilise marrow stem cells for peripheral blood stem cell transplantation. Interleukin (IL)-1, -2, -3, -4, -6 and -11 have been tested in clinical trials. However, the value of these agents remains to be established.
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PMID:[Cytokines in the treatment of blood diseases]. 754 26

In August, 1992, we established a leukemic cell line (NS-Meg) from a patient in megakaryoblastic transformation of Philadelphia chromosome-positive chronic myeloid leukemia. The NS-Meg cells were positive for alpha-naphthyl acetate esterase and periodic acid-Schiff (PAS) staining and for surface CD4, CD7, CD13, CD34, CD41a, and glycophorin A antigens. Ultrastructurally, the cells had alpha-granules, demarcation membranes, and platelet peroxidase activity. The NS-Meg cells spontaneously produced platelet-like particles which contained alpha-granules, mitochondria and dense bodies, strongly suggesting platelet production. Erythropoietin (Epo), granulocyte/macrophage colony stimulating factor(GM-CSF), and interleukin 3 (IL-3) promoted the growth of NS-Meg cells. Phorbol-12-myristate-13-acetate increased the expression of both CD41a and CD61 antigens. Ten-day exposure to Epo induced mature erythroblasts and red cells. These benzidine-positive cells were positive for hemoglobin F staining. Untreated NS-Meg cells expressed mRNA for the Epo receptor (EpoR), for GATA-1, and for alpha 1, alpha 2 and gamma globin genes. These results indicate that NS-Meg cells undergo terminal differentiation of both megakaryocytic and erythroid lineages. This cell line should be a very useful tool for the investigation of both megakaryocytic and erythroid maturation.
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PMID:A newly established megakaryoblastic/erythroid cell line that differentiates to red cells in the presence of erythropoietin and produces platelet-like particles. 771 48

The BCR/ABL oncogene encodes an activated tyrosine kinase that causes human chronic myelogenous leukemia. The mechanism of transformation, however, is complex and not well understood. One of the important contributions of BCR to transformation is believed to be dimerization or oligomerization of ABL, thereby activating ABL tyrosine kinase activity. We reasoned that if ABL was dimerized through other mechanisms, activation of the tyrosine kinase activity should also result, and the activated kinase may also be transforming. Erythropoietin is known to activate its receptor by causing dimerization, and therefore a synthetic oncogene was created by linking the extracytoplasmic and transmembrane domains of the EPO receptor with c-ABL. This chimeric receptor was stably expressed in Ba/F3 cells and, in the absence of EPO, had no detectable biological effect on the cells. EPO, however, induced a rapid, dose-dependent activation of ABL tyrosine kinase activity and phosphorylation of several cellular proteins. The major target proteins have been identified, and are very similar to the known substrates of BCR/ABL, including Shc, CBL, CRKL, and several proteins in the cytoskeleton. EPO treatment also resulted in biological effects that were remarkably similar to those of BCR/ABL, including improved viability, altered integrin function, and a weak mitogenic signal. The biological effects were in part dose-dependent, in that low EPO concentrations enhanced viability but did not cause proliferation. At high EPO doses, kinase activation was maximal, and a mitogenic effect was also revealed. In nude mice, Ba/F3 cells expressing this chimeric receptor did not cause detectable disease without administration of pharmacologic doses of EPO. If EPO was given intraperitoneally 5 days a week, however, a dose-dependent lethal leukemia resulted. This ligand-regulatable oncogene mimics some of the biological effects of BCR/ABL, and analysis of ABL mutants in this system will be useful to dissect the signaling pathways that cause CML.
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PMID:A chimeric receptor/oncogene that can be regulated by a ligand in vitro and in vivo. 931 68

Erythropoietin (Epo)-independent differentiation of erythroid progenitors is a major characteristic of myeloproliferative disorders, including chronic myeloid leukemia. Epo receptor (EpoR) signaling is crucial for normal erythroid development, as evidenced by the properties of Epo(-/-) and EpoR(-/-) mice, which contain a normal number of fetal liver erythroid progenitors but die in utero from a severe anemia attributable to the absence of red cell maturation. Here we show that two constitutively active cytoplasmic protein tyrosine kinases, P210(BCR-ABL) and v-SRC, can functionally replace the EpoR and support full proliferation, differentiation, and maturation of fetal liver erythroid progenitors from EpoR(-/-) mice. These protein tyrosine kinases can also partially complement the myeloid growth factors IL-3, IL-6, and Steel factor, which are normally required in addition to Epo for erythroid development. Additionally, BCR-ABL mutants that lack residues necessary for transformation of fibroblasts or bone marrow cells can fully support normal erythroid development. These results demonstrate that activated tyrosine kinase oncoproteins implicated in tumorigenesis and human leukemia can functionally complement for cytokine receptor signaling pathways to support normal erythropoiesis in EpoR-deficient cells. Moreover, terminal differentiation of erythroid cells requires generic signals provided by activated protein tyrosine kinases and does not require a specific signal unique to a cytokine receptor.
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PMID:BCR-ABL and v-SRC tyrosine kinase oncoproteins support normal erythroid development in erythropoietin receptor-deficient progenitor cells. 1055 95

The article describes the clinical observation of a patient with simultaneous course of lymphoid and myeloid neoplasms. The patient developed two diseases--chronic myeloid leukemia (CML) and multiple myeloma (MM), which were confirmed by corroborated hemogram, myelogram, immunophenotyping of bone marrow cells, biopsy, immunohistochemical, cytogenetic, biochemical and radiological studies. Target therapy of CML with tyrosine kinase inhibitors (imatinib at the standard dose of 400 mg per day) has provided a complete cytogenetic remission at 6 months and major molecular response at 18 months of treatment. Administration of 2 courses of programmed treatment "BD" > (bortezomib + dexamethasone) resulted in a very good partial response, which was maintained through a year and a half. However, against the background of programmed treatment there were developed complications as polyneuropathy of grade 2, which was treated with thioctacide, milgamy, and anemia of grade 2, successfully treated with epoetin beta. Subsequently, the patient was administered continuously with imatinib 400 mg that kept the major molecular response. Relapsed MM was revealed in 20 months and confirmed by a full clinical and hematological examination. The absence of organ dysfunction allowed choosing a supervisory tactics for the patient.
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PMID:[The combination of chronic myeloid leukemia and multiple myeloma in one patient]. 2381 59

Busulfan is one of the most effective chemotherapeutic agents used for the treatment of chronic myeloid leukemia. Busulfan is involved in secondary malignancy due to its genotoxic potential in normal tissues. As an alkylating agent busulfan can cause DNA damage by cross-linking DNAs and DNA and proteins, induces senescence in normal cells via transient depletion of intracellular glutathione (GSH) and subsequently by a continuous increase in reactive oxygen species (ROS) production. Erythropoietin, a glycoprotein widely used against drug induced anemia in cancerous patients and regulates hematopoiesis, has been shown to exert an important cyto-protective effect in many tissues. Recombinant human erythropoietin has been demonstrated to directly limit cell injury and ROS generation during oxidative stress. Furthermore, rhEPO decreased levels of pro-apoptotic factor (Bax) and also increased expression of the anti-apoptotic factor Bcl2. According to EPO's short half-life and requirements for the frequently administration, finding the new strategies to attenuate its side effects is important. The aim of this study was to explore whether rhEPO loading chitosan-tripolyphosphate nanoparticles protects against busulfan-induced genotoxicity in HepG2 cells. For this purpose cells were incubated with busulfan alone, regular rhEPO alone and regular rhEPO and CS-TPP-EPO nanoparticles along with busulfan in pre and co-treatment condition. Our results showed that busulfan induced a noticeable genotoxic effects in HepG2 cells (p<0.0001). Both regular rhEPO and CS-TPP-EPO nanoparticles reduced the effects of busulfan significantly (p<0.0001) by reduction of the level of DNA damage via blocking ROS generation, and enhancement intracellular glutathione levels. CS-TPP-EPO nanoparticles were more effective than regular rhEPO in both pre and co-treatment conditions. In conclusion, our results show that administration of rhEPO and CS-TPP-EPO nanoparticles especially in the pre-treatment conditions, significantly decreased the level of DNA damage induced by busulfan, measured with the comet assay, in HepG2 cells compared to the regular rhEPO group.
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PMID:Role of recombinant human erythropoietin loading chitosan-tripolyphosphate nanoparticles in busulfan-induced genotoxicity: Analysis of DNA fragmentation via comet assay in cultured HepG2 cells. 2739 35