Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The plasma level of tumor necrosis factor (TNF) was determined in 20 normal individuals, 52 patients with disseminated intravascular coagulation (DIC), 22 pre-DIC patients, and 39 non-DIC patients. TNF was not detected in the normal subjects, and the level was very low in non-DIC patients. However, the TNF level was significantly elevated in DIC patients, and it was moderately increased in pre-DIC patients shortly before the onset of DIC. This increase in circulating TNF may be associated with DIC. TNF was higher in DIC associated with solid cancer than in DIC associated with leukemia or sepsis. The increase in plasma TNF level was mildly correlated with DIC score, and it was significantly increased in patients with poor prognosis. However, the plasma TNF level in DIC patients with organ failure was not significantly different from those without organ failure. We conclude that the increase in circulating TNF reflects the pathogenic factors in DIC rather than being a consequence of organ failure due to DIC.
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PMID:Plasma level of tumor necrosis factor in disseminated intravascular coagulation. 185 67

Differentiation-linked expression of plasminogen activator inhibitor-2 (PAI-2) was investigated by adding cell-differentiation promoting agents [such as phorbol myristate acetate (PMA), retinoic acid, dexamethasone (Dex), and recombinant cytokines, including tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta, granulocyte-colony stimulating factor, and interleukin-6 (IL-6)] into the culture medium of a promyelocytic leukemia cell line PL-21. PAI activity both in the culture medium and in the cell lysate increased approximately 70-fold after exposure to PMA. Both PAI-1 and PAI-2 antigens increased, but the amounts of the latter in the culture medium and in the cell lysate were approximately 10 times and 2,500 times, as much, respectively, as those of the former. Dex also increased the intracellular PAI activity approximately 6-fold, parallel with PAI-2 antigen. PAI-1 antigen increased only slightly in the culture medium but not in the cell lysate after Dex-stimulation. As with the case of PMA, TNF-alpha and IL-6 induced PL-21 cells to macrophage-like cells, but did not affect the PAI activity. Thus, the increase of the PAI-2 production by PMA may not necessarily depend on differentiation into macrophages. Other cytokines examined did not increase the PAI activity. PAI-2 antigen was demonstrated in the cell lysates of various leukemia cells by Western blotting technique using a monoclonal antibody against the PAI-2 purified from PL-21 culture medium. PAI-2 antigen was frequently detected in the plasmas from the patients whose peripheral leukocytes were more than 10,000/microliters.
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PMID:[Production and secretion of the plasminogen activator inhibitor type-2 in a leukemia cell line]. 187 Feb 66

We investigated the effect of recombinant human interleukin-4 (rhIL-4) on the in vitro growth of human leukemia cells in liquid culture and 3H-thymidine incorporation and found inhibitory effects on the growth of leukemic cells from patients with Ph1-positive acute lymphoblastic leukemia (Ph1 ALL) and three Ph1 ALL cell lines. However, no inhibitory effects were seen in Ph1-positive leukemic cell lines derived from patients with chronic myelogenous leukemia in blast crisis and various types of Ph1-negative leukemia cells, including B-lineage leukemia cells. In a flow cytometry assay of IL-4 receptor (IL-4R), all three Ph1-positive ALL cell lines showed the presence of IL-4R on their cell surfaces, and the IL-4-dependent inhibition on the growth of Ph1-positive ALL cells was abrogated by the addition of either monoclonal or polyclonal antibodies against rhIL-4. Other cytokines, including IL-2, IL-3, granulocyte-macrophage colony-stimulating factor (CSF), granulocyte-CSF, and IL-6, showed no inhibitory effects on the growth of Ph1-ALL cells, but tumor necrosis factor-alpha (TNF-alpha) and interferon (IFN)-alpha, -beta, and -gamma displayed slight inhibitory effects in a high concentration. The growth inhibition induced by rhIL-4 in the Ph1-positive ALL cells was not abrogated by the addition of antibodies against either IFN-gamma or TNF-alpha. Furthermore, these cells showed no significant production of IFN-alpha, -beta, or -gamma or TNF-alpha after exposure to rhIL-4, thus indicating that the growth inhibition of Ph1-positive ALL cells by rhIL-4 is not associated with IL-4-stimulating production of these factors. rhIL-4 caused significant inhibition of the tyrosine kinase activity in these Ph1-positive ALL cells, similar to Herbimycin A, an inhibitor of tyrosine kinase that inhibited the tyrosine kinase activity in these cells. Our finding suggests that the clinical evaluation of rhIL-4 may offer promising therapeutic possibilities for patients with Ph1-positive ALL.
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PMID:Inhibitory effect of interleukin-4 on the in vitro growth of Ph1-positive acute lymphoblastic leukemia cells. 188 23

To clarify the role of cytokines in cerebrospinal fluid (CSF) in the pathogenesis of central nervous system (CNS) leukemia, three cytokine activities, interleukin 1 (IL-1)-beta, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma, and their correlations with other laboratory studies of the CSF were analysed in 23 children with acute leukemia. These patients were classified into three groups: group A (n = 8)--patients with overt CNS leukemia, group B (n = 5)--patients with CNS leukemia in remission, group C (n = 10)--patients without CNS disease. IFN-gamma in the CSF was undetectable in these 23 patients. There was no difference in IL-1-beta levels among the three groups. However, TNF-alpha levels were significantly higher in group A than in group B, and higher in group B than in group C. By Kendall's rank sum test, high TNF levels in CSF correlated with high CSF leukemic cell counts and low sugar levels. In two patients with overt CNS leukemia, the TNF level in the CSF decreased gradually with intrathecal chemotherapy. These results indicate that TNF released from stimulated cells in the cerebrospinal space may induce CNS leukemia-related symptoms or alter laboratory parameters measured in the CSF. TNF levels in CSF may also prove useful in diagnosing early CNS involvement in children with acute leukemia.
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PMID:Tumor necrosis factor in the cerebrospinal fluid of children with central nervous system leukemia. 190 28

A protein variously termed leukemia inhibitory factor (LIF), differentiation-inducing factor, differentiation inhibitory activity or human interleukin for DA cells can control the differentiation and proliferation of hematopoietic cells as well as of several other cellular lineages. In order to further elucidate the spectrum of LIF-producing cells, we examined different cell types for the expression of LIF mRNA using Northern blot analysis. LIF mRNA was detected in activated normal human T-cells and in two T-cell lines but was undetectable in a B-lymphoid cell line, in both resting and activated normal human granulocytes and monocytes and in human myeloid cell lines K562 and HL-60. In human lung fibroblasts and in human umbilical vein endothelial cells, LIF was constitutively expressed and its accumulation was increased in a time-dependent manner following treatment with the phorbol ester TPA and in the presence of the two immediate response cytokines tumor necrosis factor (TNF)-alpha and interleukin (IL)-1-beta. We conclude that mRNA for LIF is not only expressed by T-cells but also in human mesenchymal cells. Expression of LIF transcripts in these cells is constitutive and can be significantly enhanced by phorbol ester, TNF-alpha and IL-1-beta.
Leukemia 1991 May
PMID:Expression of leukemia inhibitory factor is regulated in human mesenchymal cells. 190 79

A child with acute myelogenous leukemia who relapsed three months after an allogeneic bone marrow transplant received intermediate-dose cytarabine followed by interleukin 2 (IL-2). Complete remission was achieved after the first cycle of IL-2. Five more combined cycles of cytarabine and IL-2 were given over the next year, during which remission has persisted. IL-2 therapy affected serum tumor necrosis factor (TNF), interferon gamma (IFN gamma) and soluble IL-2 receptor (sIL-2r) levels. In vitro cytotoxicity against leukemia cell lines and recipient leukemia cells was also increased.
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PMID:Therapy of advanced acute myeloblastic leukemia with cytarabine and interleukin 2. 191 Jan 27

Trans-activating activities of certain cellular promoter/enhancer genes may reflect the underlying mechanism for cellular differentiation. We have used two promonocytic leukemia cell lines, U937 and HL-CZ, which differ in their differentiation antigen expression. While both cell lines express CD15 antigen, only the former expresses both CD4 and CD10 antigens. These phenotypes suggest that these two cell lines appear to be arrested at different stages of differentiation. Some regions of the long terminal repeat (LTR) of human immunodeficiency virus-1 (HIV-1) contain nucleotide sequences which bind cellular trans-activating factors such as NF-kappa B and Sp1. These sequences are also present in cellular regulatory gene sequences. The cell lines have been transfected by electroporation with a nested series of deletion mutants containing different lengths of the promoter/enhancer region for HIV-LTR. The promoter/enhancer region has been linked to a 'reporter' chloramphenicol acetyl transferase (CAT) gene. We have found that promoter/enhancer trans-activation is markedly enhanced by treating transfected cells with 12-O-tetradecanoylphorbol-13-acetate (TPA), while similar treatment with tumor necrosis factor-alpha (TNF alpha) slightly enhanced activation. U937 cells always showed much greater transactivating activities than did HL-CZ cells. Deletion of a negative regulatory element (NRE) from the LTR resulted in an enhanced transactivation, while deletions affecting NF-kappa B and/or Sp1 binding sites markedly reduced transactivation. Deletion of both NRE and NRF, a second negative regulatory factor binding site, from the LTR restored the transactivation. However, in the presence of TPA, deletion of NRE sequence without concomitant deletion of the downstream NRF binding sequence was sufficient for recovering transactivation. Since these two cell lines have shown subtle differences in these responses, it may be speculated that monocytes at different stages of differentiation may respond in different ways, qualitatively and/or quantitatively, to signal transduction factors involved in the transactivation of cellular genes.
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PMID:Regulation of cellular trans-activating activities in two different promonocytic leukemia cell lines. 191 29

Previous studies have revealed a consistent defect in the cycling behavior of primitive neoplastic progenitor cells in patients with Philadelphia chromosome (Ph1)-positive chronic myeloid leukemia (CML). This is manifested both in vivo and in long-term cultures of CML cells as an increased rate of turnover amongst Ph1-positive progenitor cell types whose counterparts in normal individuals are mainly quiescent. To determine whether this deregulated proliferative activity of primitive Ph1-positive cells might be explained by a perturbation in the production of growth factors that regulate the turnover of primitive normal cells, the possibility of either autocrine or paracrine mechanisms of Ph1-positive cell stimulation was investigated. Northern blot analysis of total cellular RNA extracted from various CML blood cell populations showed no evidence of increased expression of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-3, IL-6, or tumor necrosis factor-alpha (TNF-alpha) compared with analogous normal peripheral blood cell populations in which transcripts for most of these growth factors are not detectable. A similar analysis of RNA extracted from the adherent layer of 4-week-old long-term cultures established from CML marrow (in which the Ph1-positive cells typically disappear) or from CML blood seeded onto normal marrow adherent layers (in which Ph1-positive cells typically persist) also revealed no difference in growth factor production compared with analogous cultures established with exclusively normal cells. For some of the growth factors studied, the assessment of bioactivity detectable in the medium confirmed the RNA data. There was also no evidence of a decreased production of putative inhibitors of primitive hematopoietic cells, i.e. transforming growth factor-beta and macrophage inflammatory protein-1 alpha by CML versus normal cells or cultures. These results do not support the existence of BCR-ABL induced autocrine or paracrine mechanisms in CML and suggest that constitutive activation of events normally dependent on growth factor receptor stimulation is more likely to underlie the lack of proliferation control exhibited by primitive Ph1-positive cells.
Leukemia 1991 Oct
PMID:Lack of evidence for abnormal autocrine or paracrine mechanisms underlying the uncontrolled proliferation of primitive chronic myeloid leukemia progenitor cells. 196 Oct 20

The DNA fragmentation induced by tumor necrosis factor (TNF) of differentiable human myeloid leukemic HL-60 cells has been further characterized. TNF increased the appearance of very high molecular weight DNA fragments detected by agarose gel electrophoresis. The use of pulsed-field gel electrophoresis (PFGE) revealed these fragments to be as high as 200-400 kilobase pairs. The pattern of HL-60 DNA fragmentation contrasted with that of U937 cells, which exhibited lower molecular weight, nucleosome multiple sized fragments, and greater cytotoxicity in response to TNF. The peak increase of fragments from HL-60 occurred between one and two hours of incubation, with TNF concentrations of 10 U/ml or higher, and was inhibitable by 1 mM Zn2+. Southern blotting of these fragments disclosed enrichment for c-myc related sequences compared with control probes including beta-actin and kappa and lambda light chains. Treatment of DNA with NotI or gamma-irradiation, followed by PFGE, disclosed a class of still higher molecular weight DNA, which decreased following TNF treatment, and which was apparently the precursor of the TNF-induced fragments. TNF thus rapidly increases a class of high molecular weight DNA fragments which are enriched for c-myc related sequences and may arise preferentially from higher molecular weight structures which are detectable following linearization by NotI or gamma-irradiation. Such major but non-random alterations in chromatin structure may contribute to TNF-induced monocytoid differentiation of HL-60.
Leukemia 1991 Oct
PMID:Induction of differentiation by tumour necrosis factor in HL-60 cells is associated with the formation of large DNA fragments. 196 Oct 21

ML-1 human myeloblastic leukemia cells, suspended in RPMI-1640 medium, differentiated to monocyte or macrophage-like cells when either tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), or tetradecanoylphorbol acetate (TPA) was added prior to or simultaneously with fetal bovine serum (FBS). When FBS was applied first, and followed, after washing, by the cytokines or by TPA, maturation did not occur. A 77 kDa glycoprotein (DF77), isolated from human leukocyte-conditioned medium and present in FBS, was capable of replacing FBS for induction of differentiation. Thus, in this cell system, TNF-alpha, TGF-beta, and TPA acted as competence factors, whereas DF77 acted as the progression signal. Optimal competence was established after exposure of the cells to TPA or to either of the cytokines for approximately 2 or 30 min, respectively. After removal of the factors, competence was retained for approximately 3 hr before it declined. These results demonstrate that the initiation of ML-1 human myeloblastic leukemia cell differentiation relied upon the sequential and ordered input of competence and progression signals.
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PMID:Tumor necrosis factor-alpha, transforming growth factor-beta, and tetradecanoylphorbol acetate: competence factors for ML-1 human myeloblastic leukemia cell differentiation. 198 43


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