Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL-60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S-nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit-granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo.
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PMID:Differential effects of nitric oxide on erythroid and myeloid colony growth from CD34+ human bone marrow cells. 856 69

Adhesion of myeloid leukemia cells to the bone marrow (BM) microenvironment is mediated in part by Beta 1 and Beta 2 integrins. Cells of the erythroleukemia line K562, derived from a patient with chronic myeloid leukemia, bind to BM fibroblasts (BMFs) but the adhesion cannot be accounted for by integrins or other known adhesion proteins including CD44 or members of the Ig or selectin families. Membrane fragments from K562 cells were radioiodinated and allowed to adhere to BMF monolayers. Adherent proteins were solubilized together with the fibroblasts, analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and visualized by autoradiography. Four adherent proteins were consistently observed. Two of these, with reduced molecular weights of 52 kD and 35 to 37 kD, were prominent. Addition of soluble thrombospondin and heparin but not fibronectin inhibited binding of K562 membrane proteins to adherent BMFs and immobilized thrombospondin- and heparin-bound K562 proteins. The 52-kD protein has a multimeric structure nonreduced and has characteristics of a glycoprotein. Its adhesion to fibroblasts is divalent cation and temperature sensitive. The 35- to 37-kD protein, whose function is divalent cation but not temperature sensitive, is phosphoinositol-linked and has characteristics identical to an adherent 35- to 37-kD protein identified on murine progenitor cells. Membrane preparations from two cases of acute myeloid leukemia showed an adherent 35- to 37-kD protein and in one case an adherent 52-kD protein without other adherent bands. A K562 subclone with reduced adherence to BMFs showed reduced amounts of adherent 52-kD and 35- to 37-kD proteins. These proteins may be responsible for the adhesion of malignant and normal hematopoietic progenitor cells to the BM microenvironment.
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PMID:Identification of novel K562 membrane proteins that adhere to bone marrow fibroblasts. 870 84

NB4 cells are the only bona fide in vitro model of human acute promyelocytic leukemia. We have examined cytidine and guanosine transport in this cell line and characterized a novel guanosine-specific transporter. Cytidine transport occurred predominately by equilibrative nitrobenzylthioinosine (NBMPR)-sensitive (es) transport. In the presence of Na+, guanosine at various concentrations accumulated at least 6-fold above equilibrium. The initial rate of guanosine transport in Na+ buffer decreased by 75% with the addition of 1 microM NBMPR and the IC50 for NBMPR inhibition was 0.7 +/- 0.1 nM. Replacement of Na+ with choline also resulted in a 75% decrease in total guanosine transport. The potent inhibition of guanosine transport by NBMPR and the loss of transport in choline suggested that a Na+-dependent NBMPR-sensitive transporter was responsible for the majority of guanosine uptake. This concentrative, sensitive transporter is Na+ dependent with a stoichiometric coupling ratio of 1:1. This novel transporter, referred to as csg, is guanosine-specific with total guanosine transport inhibited by only 50% in the presence of 1 mM competing nucleosides. HL-60, acute myelocytic leukemia cells, do not exhibit csg activity while L1210, murine acute lymphocytic leukemia cells, exhibit csg transport. The presence of the csg transporter suggests an important role for guanosine in particular forms of leukemia and may provide a new target for cytotoxic therapy.
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PMID:Characterization of a novel Na+-dependent, guanosine-specific, nitrobenzylthioinosine-sensitive transporter in acute promyelocytic leukemia cells. 921 31

lnterleukin-2 (IL-2) is known to cause xerostomia and skin manifestations similar to graft-versus-host disease (GVHD). We therefore evaluated major salivary gland function in patients with hematological malignancies treated with IL-2 and interferon-alpha (IFN-alpha) after ABSCT. Eleven patients (seven male, four female) of median age 40 (24-47) were evaluated, seven with non-Hodgkin lymphoma (NHL); one with Hodgkin's disease (HD) and three with acute myelogenous leukemia (AML). Parotid and submandibular salivary gland function was assessed before, during and after IL-2/IFN-alpha administration by evaluation of the salivary flow rate and the composition of secreted saliva. Significant reductions in both the resting and stimulated parotid and submandibular salivary flow rates were observed during IL-2/IFN-alpha immunotherapy compared with the pre- and post-therapy values (P < 0.01), while no hyposalivation was observed in the control patients who underwent ABSCT and did not received IL-2. Sialochemical evaluation revealed a significant increase in potassium concentration (24.4+/-0.6 mEq/l to 28.9+/-1.4 mEq/l) and a significant decrease in sodium concentration (6.7+/-2.1 mEq/l to 3.3+/-1.0 mEq/l) (P < 0.05) in the stimulated parotid gland saliva secreted during IL-2/IFN-alpha administration. Salivary protein concentrations were not altered by the IL-2/IFN-alpha immunotherapy. Similar changes were previously observed in mice and humans with chronic GVHD. We conclude that IL-2 immunotherapy induces major salivary gland dysfunction in humans, similar to our previous observations in patients with chronic GVHD, which may indicate similar pathophysiologic mechanisms.
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PMID:Major salivary gland dysfunction in patients with hematological malignancies receiving interleukin-2-based immunotherapy post-autologous blood stem cell transplantation (ABSCT). 933 59

This report describes the analysis of culture cells and blast cells separated from the heparinized bone marrow and whole blood of patients with acute leukemias by means of a density-gradient technique (Ficoll-sodium metrizoate d = 1.077 g/cm3). Cell-surface antigens were analyzed by a fluorescence-activated cell sorter using a panel of monoclonal antibodies (MAbs). The blast cells and culture cells were fixed by 3% paraformaldehyde in phosphate-buffered saline. A low level of expression of MPO precursor protein was found in THP-1. K-562 and HEL, MEG-01, erythro-megakaryocytic leukemia cell lines, Jurkat, MOLT-3, MOLT-4, RPM18402, ATL-5, T-cell leukemia cell lines, Raji, Daudi. BALL-1, B-cell leukemia cell lines, and AGNK1 showed negative reaction. The de novo MPO-negative acute leukemias, middle level of expression of MPO precursor protein, was found in the blasts of MPO-negative AML (AML, M0), which coexpressed CD13, CD33, CD34, and CD38. A high level of expression of MPO protein was found in all cases of AML, M1, and M2. The MPO expression was not found in all cases of acute lymphoblastic leukemia. The highest level of MPO expression was found in cases of AML, M3, and AML, M3v, suggesting the diagnostic value for this type of leukemia. The detection of MPO precursor protein by flow cytometric analysis with monoclonal antibodies is essential for the determination of lineage and precise diagnosis of acute unclassifiable leukemia, and should contribute substantially to the development of an effective form of therapy and cure.
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PMID:Sensitive detection technique of myeloperoxidase precursor protein by flow cytometry with monoclonal antibodies. 966 78

Serine phosphorylation of bcl-2 has been reported after treatment of cells with protein kinase C, okadaic acid, taxol, and other chemotherapeutic agents that attack microtubules. We report here that bcl-2 is phosphorylated on serine in acute myeloblastic leukemia (AML) blasts exposed to all trans retinoic acid (ATRA). Two-dimension gels (isoelectric focusing followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE]) disclosed a novel acidic isoform of bcl-2 in ATRA-treated blast cells from a continuous line and from two AML patients; when the cell lysates were digested with lambda-phosphatase, bcl-2 reverted to the control position, indicating that it was phosphorylated. Metabolic labeling experiments using 32Pi showed that, while control bcl-2 was labeled, incorporation was greatly increased when cells were treated with ATRA. A comparison of bcl-2 from blasts treated with ATRA or taxol showed that bcl-2 was phosphorylated on serine in cells treated with either agent; however, both qualitative and quantitative differences were seen. Qualitatively, the phosphorylated isoform from taxol-treated cells was slightly larger than the native isoform and could be distinguished on 10% to 20% SDS-polyacrylamide gradient gels, while the phosphorylated bcl-2 after ATRA ran as a single band on gradient gels at the same position as control bcl-2. Quantitatively, all bcl-2 from ATRA-treated cells was in the phosphorylated isoform, while after taxol, both phosphorylated and native bcl-2 was present; incorporation of 32Pi into bcl-2 was stimulated to greater extent in ATRA-treated compared with taxol-treated cells. We used immunoprecipitation experiments to ask if bcl-2 phosphorylated after ATRA or taxol had altered capacity to dimerize with bax. No change in dimerization was demonstrated. We conclude that: bcl-2 is phosphorylated on serine after treatment of AML blasts with ATRA; bcl-2 phosphorylation after ATRA is different from that seen after taxol; bcl-2 phosphorylated after either agent retains capacity to dimerize with bax. The ATRA or taxol-induced phosphorylation of bcl-2 can also be seen in blast cells obtained from AML patients.
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PMID:Phosphorylation of BCL-2 after exposure of human leukemic cells to retinoic acid. 971 7

Both p15 and p16 are tumor suppressor genes that have 5' CpG islands; aberrant cytosine methylation of these islands has been associated with silencing of their expression. Deoxycytidine kinase (dCK) converts prodrugs to their cytotoxic form, has a 5' CpG island and is a candidate gene for inactivation by hypermethylation. In our study, we used sodium bisulfite sequencing to generate high resolution maps of 5-methylcytosine in the CpG islands associated with p15, p16 and dCK in normal human bone marrow (BM), peripheral blood lymphocytes (PBL) and cytosine arabinoside (ara-C)-resistant acute myeloid leukemia (AML) patients, and established human hematopoietic tumor cell lines. In normal cells the p15, p16 and dCK CpG islands were largely unmethylated. The p16 and dCK CpG islands were also unmethylated in the 8 AML specimens. In contrast, the p15 CpG island was aberrantly methylated in 6 of the 8 AML specimens. Furthermore, bisulfite sequencing revealed that the p15 CpG island is heterogeneously methylated in AML, with large intra-individual and inter-individual variability.
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PMID:Selective variegated methylation of the p15 CpG island in acute myeloid leukemia. 980 23

Sodium phenylacetate (PA) and sodium phenylbutyrate (PB) are aromatic fatty acids that can effect differentiation in a variety of cell lines at doses that may be clinically attainable. We have studied the impact of these two agents on lineage- and differentiation stage-specific antigen expression, proliferation, apoptosis, and clonogenic cell survival in primary cultures of bone marrow samples from patients with myeloid neoplasms at presentation and in remission and from normal volunteers. PB inhibited the proliferation of primary acute myeloid leukemia cells in suspension culture with an ID50 of 6.6 mM, similar to its ED50 in cell lines. At higher doses (>/=5 mM), PB also induced apoptosis. PB inhibited clonogenic leukemia cell growth with a median ID50 of less than 2 mM; however, colony-forming units-granulocyte/macrophage from patients with myelodysplasia and normal volunteers were inhibited with a similar ID50. In contrast to PB, its metabolite PA had no significant effect on either acute myeloid leukemia proliferation or apoptosis. Expression of the monocytic marker CD14 was increased in monocytic and myelomonocytic leukemias in response to PB, and to a lesser extent, PA. Surprisingly, both agents appeared to increase expression of the progenitor cell antigen CD34, as well as the DR locus of the human leukocyte antigen. These data indicate that PB, but not its metabolite PA, has significant cytostatic and differentiating activity against primary neoplastic myeloid cells at doses that may be achievable clinically.
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PMID:Impact of the putative differentiating agents sodium phenylbutyrate and sodium phenylacetate on proliferation, differentiation, and apoptosis of primary neoplastic myeloid cells. 981 60

Increased levels of DNA-protein cross-links (DNAPC) have been observed in vitro and in vivo following treatment with a number of chemotherapeutic alkylating agents and topoisomerase II inhibitors, that is, agents that have also been associated with the development of bone marrow depression and acute myelogenous leukemia. The current studies were undertaken to examine the effect of benzene, a bone marrow toxin and human leukemogen, on DNAPC levels in mouse bone marrow cells. Using a K+/sodium dodecyl sulfate (SDS) precipitation assay for DNAPC determination, the results indicate increased DNA-protein cross-link levels in mouse bone marrow cells at 2 and 4 but not 8 h after a single ip injection of 440 mg/kg benzene. Following the administration of multiple hematotoxic benzene doses (440 or 880 mg/kg, 2x/d for 2 d), increases in DNA-protein cross-link levels were either slight or not present. These results suggest that DNAPC induced by benzene are neither cumulative nor persistent lesions. The toxicity of benzene is mediated by a number of number of ring-hydroxylated and ring-opened compounds; therefore the present studies also examined DNAPC levels in mice administered trans,trans-muconaldehyde (MUC), a ring-opened hematotoxic and genotoxic metabolite of benzene. No marked increases in DNAPC levels were observed in CD- mouse bone marrow cells 1-12 h following a single ip injection of 3 mg/kg muconaldehyde. It is possible that multiple doses of MUC are required to induce elevated DNAPC levels in bone marrow cells of mice, since multiple doses are required for MUC-induced hematotoxicity. Other reactive metabolites and/or an interaction of reactive intermediates may also be involved in DNAPC induced by benzene.
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PMID:DNA-protein cross-link levels in bone marrow cells of mice treated with benzene or trans,trans-muconaldehyde. 1009 61

Histone deacetylase inhibitors (HDACIs) have been used to focus on the effects of inducing gene expression through the acetylation of histones which results in chromatin remodeling. The study explored whether HDACIs could induce the expression of costimulatory/adhesion molecules on acute myeloid leukemia (AML) cells, thereby effectively inducing tumor immunity. The expression of CD80, CD86, human leukocyte antigen (HLA)-DR, HLA-ABC, and intracellular adhesion molecule-1 (ICAM-1) was tested in human AML cell lines after the addition of HDACI, sodium butyrate (SB). Generally, increased expression of CD86 was observed by SB treatment in a majority of cell lines, and ICAM-1 was expressed in fewer cell lines. Essentially the same results were obtained using other HDACIs such as FR901228, trichostatin A, and trapoxin A. Quantitation of transcripts of CD86 accompanied with RNA synthesis inhibition assay and nuclear run-on assay revealed that SB up-regulates the CD86 expression transcriptionally. Furthermore, chromatin immunoprecipitation experiments showed that HDACI treatment caused remarkable acetylation on histone H3 and H4 at CD86 promoter chromatin in vivo. In 30 clinical AML samples, CD86 expression was significantly increased (P <.001) by SB treatment, and the expression of HLA-DR and ICAM-1 was moderately increased (P <.05) by SB treatment. Finally, the allogeneic mixed leukocyte reaction (allo-MLR) against HL60 cells pretreated with SB was enhanced 4-fold compared with allo-MLR obtained with non-treated HL60 cells. These results suggest that the immunotherapeutic use of HDACIs may become a novel tool for treatment of AML. (Blood. 2000;96:3847-3856)
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PMID:Up-regulation of costimulatory/adhesion molecules by histone deacetylase inhibitors in acute myeloid leukemia cells. 1109 69


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