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)

We gave 56 patients with newly diagnosed acute myelogenous leukemia (AML) granulocyte-macrophage colony-stimulating factor (GM-CSF) 20 or 125 micrograms/m2 once daily subcutaneously before (for up to 8 days or until GM-CSF-related complications developed) and during, or only during (patients presenting with blast counts greater than 50,000 or other leukemia-related complications) ara-C (1.5 g/m2 daily x 4 by continuous infusion) and daunorubicin (45 mg/m2 daily x 3) chemotherapy. Because results seemed independent of GM-CSF schedule, we compared results in these 56 patients with results in 176 patients with newly diagnosed AML given the same dose and schedule of ara-C without GM-CSF (110 patients ara-C alone, 66 patients ara-C + amsacrine or mitoxantrone). Comparison involved fitting a logistic regression model predicting probability of complete remission (CR) and a Cox regression model to predict survival (most patients in all three studies were dead) with treatment included as a covariate in both analyses. After adjusting for other prognostically significant covariates [presence of an antecedent hematologic disorder, an Inv (16), t(8;21), or abnormalities of chromosomes 5 and/or 7, performance status, age, bilirubin], treatment with ara-C + daunorubicin + GM-CSF was predictive of both a lower CR rate and a lower survival probability. There were no treatment-covariate interactions, suggesting that the negative effect of this GM-CSF treatment regime was not an artifact of some imbalance in patient characteristics. The unadjusted Kaplan-Meier hazard rate of the ara-C + daunorubicin + GM-CSF group was not uniquely high during the initial 4 weeks after start of therapy, but was highest among the three treatment groups throughout weeks 5 to 16, suggesting that the negative effect of this treatment was not caused by acute toxicity. Patients who did not enter CR with this treatment tended to have persistent leukemia rather than prolonged marrow aplasia, suggesting that this treatment and, in particular, GM-CSF may increase resistance of myeloid leukemia cells to chemotherapy. To date, relapse rates are similar in all three groups (P = .43) (as are survival rates once patients are in CR) but much of the remission duration data is heavily censored, unlike the survival data. Our results suggest caution in the use of GM-CSF to sensitize myeloid leukemia cells to daunorubicin + ara-C chemotherapy.
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PMID:Treatment of newly diagnosed acute myelogenous leukemia with granulocyte-macrophage colony-stimulating factor (GM-CSF) before and during continuous-infusion high-dose ara-C + daunorubicin: comparison to patients treated without GM-CSF. 157 41

The p53 gene is currently considered to function as a tumor-suppressor gene in various human malignancies. In hematologic malignancies, alterations in the p53 gene have been shown in some human leukemias and lymphomas. Although mutations in the p53 gene are infrequent in acute myelogenous leukemia (AML) patients, we show in this report that alterations in the p53 gene are frequent in myeloid leukemia cell lines. We studied alterations of the p53 gene in nine human myeloid leukemia cell lines by reverse transcriptase-polymerase chain reaction (RT-PCR), single-strand conformation polymorphism (SSCP) analysis, and direct sequencing. Expression of the p53 gene was not detected at all by RT-PCR in two of the nine cell lines. In these two cell lines, Southern blot analysis showed gross rearrangements and deletions in both of the p53 alleles. Six of the nine cell lines were found to express only mutant p53 mRNA by RT-PCR/SSCP analysis and direct sequencing, and wild-type p53 mRNA was not detected. Two of the mutant p53 mRNAs were shown to be products of abnormal splicing events induced by intronic point mutations. Taken together, eight of nine human myeloid leukemia cell lines expressed no or an undetectable amount of wild-type p53 mRNA. Three of the eight cell lines were growth factor-dependent. Our results suggest that inactivation of the p53 gene may be a common feature in myeloid leukemia cell lines and may play an important role in the establishment of these cell lines.
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PMID:Frequent mutations in the p53 gene in human myeloid leukemia cell lines. 157 49

Interleukin-6 (IL-6) has been shown to inhibit growth and induce differentiation of several myeloid leukemia cell lines. In this work, two in vivo models of acute myeloid leukemia (AML) in mice have been used to test the therapeutic potential of recombinant human IL-6. In mice inoculated by a transplantable AML tumor, IL-6 injections inhibited the development of leukemia and increased survival. The effect was related to dose and length of treatment. In a model of radiation-induced leukemogenesis in SJL/J mice, administration of low-dose IL-6 for 10 days, 4 months after irradiation, reduced the incidence of leukemia observed during 1 year, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF) increased the incidence of leukemia. In vitro liquid cultures of leukemic blood cells obtained from AML patients showed that IL-6 slowed growth and decreased the proportion of blasts with an increase in more mature myeloid elements in 72% of M1, M2, M4 AML cases. In contrast, GM-CSF less often produced differentiation but stimulated leukemic cell growth in liquid cultures, without synergism by IL-6.
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PMID:Antitumor effects of human recombinant interleukin-6 on acute myeloid leukemia in mice and in cell cultures. 157 51

The lamins are intermediate filament proteins that form a fibrous layer at the periphery of the nucleus. Experiments in cell-free systems have suggested that mammalian lamins A and C mediate an interaction between chromatin and the inner nuclear membrane that is essential for the reformation of the nucleus after mitosis. Other investigations, however, have suggested that lamins A and C are absent from myeloid cells and myeloid leukemia cell lines. To further investigate this apparent paradox, highly sensitive Western blotting techniques were utilized in the present study to examine the expression of lamins A and C in a series of human myeloid leukemia cell lines and in bone marrow samples from patients with acute nonlymphocytic leukemia (ANLL) and chronic myelogenous leukemia. Western blotting revealed that HL-60 progranulocytic leukemia cells contained an average of 0.1 x 10(6) copies of lamins A and C per cell compared to 0.5 x 10(6) copies of lamin B1 (the quantitatively prominent human B-type lamin) per cell. During the process of phorbol ester-induced maturation to macrophages, the mRNA for lamins A and C increased in abundance, with a concomitant 4-fold increase in the average cellular content of these polypeptides. To rule out the possibility that the low but detectable levels of lamins A and C observed in untreated HL-60 cells reflected incipient maturation, the content of lamins A and C was analyzed in ANLL cell lines that do not mature toward granulocytes or monocytes. Lamins A and C were readily detected in cell lines (KG1a, HEL, Mo-7e) derived from patients with a variety of subtypes of ANLL. Expression of lamins A and C was not limited to myeloid cell lines. These polypeptides were also detectable in marrow samples from 9 of 26 patients with ANLL including at least 1 patient from each of the 5 subtypes of ANLL examined. In contrast, only 1 of 12 marrow samples from patients with aggressive phase chronic myelogenous leukemia and chronic myelogenous leukemia in blast crisis contained readily detectable lamins A and C. The implications of these findings for current hypotheses regarding the functions of the lamin polypeptides are discussed.
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PMID:Expression of nuclear envelope lamins A and C in human myeloid leukemias. 158 98

Myeloid leukemia development requires the acquisition by a cell of two abnormalities: an abnormal capacity for self-replication; and a capacity for autocrine stimulation, usually involving the known growth factors for granulocyte-macrophage cells. Curiously, in human leukemia, this does not usually result in autonomous growth when assessed in clonal in vitro cultures. Depending on gene programming, in particular in human or murine myeloid leukemias, the hemopoietic growth factors can also suppress the leukemic population by inhibiting the capacity of the leukemic stem cells for self-generation. The regulator showing the highest suppressive activity varies from leukemia to leukemia, with G-CSF. GM-CSF, IL-6, or leukemia-inhibitory factor (LIF) all having high activity on appropriate target cells. Combinations of these regulators are more effective than single agents alone. Analyses of human HL60, U937 and murine M1 leukemic models indicate that the development of morphological maturation in the leukemic cells is not a necessary feature of stem-cell suppression. LIF has an anomalous action on stem-cell self-generation, being highly effective in the suppression of certain myeloid leukemic cell lines, but being necessary to maintain self-generation in normal embryonic cells. This suggests the existence of a common control medium governing self-generation decisions in cells of different lineages, but that the outcome of the decision is determined by the differentiation program operating in different cells. The colony-stimulating factors are being used in combination with chemotherapy in the treatment of patients with acute myeloid leukemia, but the above principles require caution in certain situations.
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PMID:Role of hemopoietic growth factors in the development and suppression of myeloid leukemia. 160 21

Human granulocyte colony-stimulating factor (G-CSF) rapidly loses the biological activity and the receptor binding capacity following radioiodination. We have made a mutein of human G-CSF, KW-2228, in which Thr-1, Leu-3, Gly-4, Pro-5, and Cys-17 were respectively substituted with Ala, Thr, Tyr, Arg, and Ser; showed more potent G-CSF activity; and retained full biological activity and receptor binding capacity at least 2 weeks of radioiodination. G-CSF is an effective growth factor for the blasts of myeloid leukemia. Radioiodinated KW-2228 was prepared using solid-phase glucose oxidase-lactoperoxidase. Human leukemia cell lines and the blast cells from leukemia patients were examined for binding. High affinity binding sites were identified on myeloid cell lines and on the blasts obtained from acute myeloid leukemia patients. Scatchard analysis showed that a single binding site for G-CSF was observed (361-1688 receptors/cell; Kd 128-1400 pM). In contrast, specific binding of 125I-KW-2228 was not demonstrated on lymphoblastic cell lines or the blast cells of acute lymphoid leukemia or lymphoma. This difference was reflected in the effectiveness of G-CSF to stimulate colony formation in acute myeloid leukemia blasts, while G-CSF did not stimulate colony formation of the blast cells from acute lymphoid leukemia.
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PMID:Receptor binding of human granulocyte colony-stimulating factor to the blast cells of myeloid leukemia. 168 9

The concept of biologic modification of proliferation and differentiation of myeloid leukemia cells has attracted much attention over the past years. One promising strategy involves the recruitment of leukemic cells into the cell cycle by hematopoietic growth factors in combination with cycle-specific cytotoxic drugs. Because cytosine arabinoside (Ara-C), which targets only cells in S-phase of the mitotic cell cycle, is included in most chemotherapeutic regimens for the treatment of acute myelogenous leukemia, we explored the hypothesis that the recruitment of quiescent immature leukemic blasts into the cell cycle by the early acting growth factor interleukin 3 (IL-3) can increase the efficacy of Ara-C for kill of leukemic stem cells. We show that IL-3 increases the fraction of blasts in S-phase, as assessed by DNA histogram analysis with propidium iodide staining, leading to an enhancement of kill of clonogenic blast cells when combined with Ara-C. Expression of the protooncogenes c-myc, c-fms, and c-fos, known to be linked to cellular proliferation and differentiation, was also altered by IL-3 in Ara-C-treated cultures, further substantiating the role that IL-3 plays as an enhancer of the cytotoxicity of Ara-C.
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PMID:Effect of interleukin 3 on cytosine arabinoside-mediated cytotoxicity of leukemic myeloblasts. 169 4

A new recurring chromosome abnormality was identified in 8 of 621 consecutive successfully karyotyped adults with de novo acute leukemia. These eight patients had trisomy 13 as the sole cytogenetic abnormality. On central morphologic review, five cases were classified as subtypes of acute myeloid leukemia, one as acute mixed lymphoid and myeloid leukemia, one as acute lymphoid leukemia, and one as acute undifferentiated leukemia. Blasts of all eight cases expressed one or more myeloid differentiation antigens. Three also expressed T-lineage-associated antigens; however, none of these had rearrangement of the T-cell receptor beta, gamma, or delta genes. Four of six cases tested were TdT positive. All eight patients with trisomy 13 were treated with intensive induction chemotherapy; only three entered a short-lived complete remission. Survival of patients with trisomy 13 ranged from 0.5 to 14.7 months, and was significantly shorter than that of the remaining patients (median 9.5 v 16.2 months, P = .007). We conclude that trisomy 13 is a rare, recurring clonal chromosome abnormality in acute leukemia associated with a poor prognosis. Malignant transformation of an immature hematopoietic precursor cell is suggested by the expression of antigens characteristic of both the myeloid and lymphoid lineage, the high incidence of TdT positivity, and the morphologic heterogeneity in these leukemias.
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PMID:Trisomy 13: a new recurring chromosome abnormality in acute leukemia. 169 82

A novel human myeloid leukemia cell line, NKM-1, was established from a patient with acute myeloid leukemia (FAB classification M2). The cells were positive for myeloperoxidase staining and cluster of differentiation 15 cell surface antigen. Radiolabeled recombinant human granulocyte (G) colony-stimulating factor (CSF) was used, and 60 specific binding sites/cell with a Kd 100 pmol/liter were demonstrated on the cell surface. 125I-G-CSF binding was not inhibited by interleukin-3, granulocyte-macrophage CSF, or macrophage (M) CSF. NKM-1 cells also expressed M-CSF receptors detected by c-fms mRNA expression. In concordance with the receptor expression, NKM-1 cells proliferated in response to exogenous G-CSF or M-CSF in a dose-dependent manner (0.1-100 ng/ml), while interleukin-3 or granulocyte-macrophage CSF had no effect. Colony-forming capacity of NKM-1 cells in semisolid agar was also enhanced with the addition of 10 ng/ml of G-CSF or M-CSF but decreased at higher concentrations. During CSF stimulation, no remarkable changes were observed morphologically and phenotypically. The stimulatory effect of G-CSF and M-CSF on the cell growth was additive. Neither G-CSF-binding capacity nor c-fms mRNA expression was altered by pretreatment with M-CSF or G-CSF, respectively. This cell line may provide a useful in vitro model for the study of CSF roles in myeloid leukemia cell proliferation.
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PMID:A novel human myeloid leukemia cell line, NKM-1, coexpressing granulocyte colony-stimulating factor receptors and macrophage colony-stimulating factor receptors. 170 53

Major histocompatibility complex-unrestricted lymphokine-activated killer (LAK) cells have been proposed as therapy for a variety of hematologic malignancies. Because these cells recognize and kill their targets independently of their antigen specific CD3 receptor, it is unclear how they might discriminate between normal and malignant cells. We now propose one such mechanism for the selective killing of myeloid leukemia blasts. While both CD2+ and CD2- activated killer cells may inhibit the clonogenic growth of myeloid leukemia cells, only the CD2+ subset effectively inhibits the growth of normal myeloid (granulocyte-macrophage and granulocyte) progenitors. This difference appears to reflect differential requirements for cell adhesion molecule recognition between normal and malignant progenitor cells. Inhibition of the growth of normal granulocyte-macrophage colonies by CD2+ LAK cells is blocked by antibodies to the CD2-lymphocyte function-associated antigen 3 (LFA-3) (CD58) cell adhesion system. In contrast, these antibodies have no effect on CD2+ LAK-mediated inhibition of malignant cell clonogenic growth. Instead, antibodies to the LFA-1 (CD11a/CD18)-intercellular adhesion molecule 1 (ICAM-1) (CD54) adhesion system reduce inhibition. These differences correspond to differential expression of the CD54 cell adhesion molecule by normal and malignant myeloid progenitor cells because less than 15% of normal CD34 positive cells are CD54+ while greater than 85% of CD34+ acute myeloid leukemia blasts express the CD54 antigen. LFA-3, the ligand for CD2, is strongly expressed by erythrocytes, and these cells competitively inhibit killing of normal but not malignant clonogenic cells in an analogous way to the effects of monoclonal antibody to the CD2-LFA-3 adhesion system. The operation of this effect in vivo may be a basis for selective cytotoxicity by CD2+ LAK against clonogenic myeloid blast cells, and could be exploited further with infusion of appropriate monoclonal antibodies.
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PMID:Possible mechanism of selective killing of myeloid leukemic blast cells by lymphokine-activated killer cells. 170 96


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