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

The effect of conditioned media of 3-day cultures of blast cells from peripheral blood of 5 patients with acute myeloid leukemia (CM-AML) was studied on the synthesis of C2, factor B (Bf) and C1 esterase inhibitor (C1-INH) by human monocyte-macrophage cultures and HepG2 hepatoma cell line. The level of C2 in the culture supernatants was measured by immune hemolysis, those of Bf and C1-INH by ELISA. CM-AML was added to the monocyte cultures on day 3 and replaced by culture fluid on day 6. Compared to the control cultures, CM-AML significantly increased C2 and Bf levels and slightly decreased C1-INH levels in the culture fluids on day 6. On day 9, Bf synthesis enhancement still could be observed but C2 and C1-INH levels did not significantly differ from those of the control. CM-AML significantly increased the synthesis of factor B by the HepG2 cells too. A strong correlation was found between the results of the Bf protein and RNA determinations, which means that the supernatants of AML blasts affect the gene expression of factor B at a pretranslational level. The selective complement synthesis modifying effect of CM-AML was not due to interferons (IFN) because neither IFN-alpha nor IFN-gamma could be detected in these conditioned media. The present findings indicate that the hypercomplementemia observed in AML patients can be due to unknown factor(s) produced by leukemic blast cells.
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PMID:Effect of conditioned media of acute myeloid leukemia blast cells on complement synthesis by cultured human cells of monocyte and hepatocyte origin. 180 54

We recently described an IL-1 inhibitor found in urine of febrile patients. It is a 26-kDa glycoprotein that acts by blocking the binding of IL-1 to its receptor. In a search for a cell source for the urinary IL-1 inhibitor, we tested three promyelocytic cell lines, H-161, AML-193, and HL-60, for their ability to produce this protein. Under normal culture conditions none of these cell lines produce detectable IL-1 inhibitory activity. The H-161 cells were treated with differentiation-inducing agents, i.e., sodium butyrate, hemin, retinoic acid, DMSO, vitamin D3, and PMA alone or in combination with IL-1 alpha, IL-2, IL-3, IL-4, IL-5, IL-6, TNF-alpha, IFN-gamma, granulocyte-CSF, macrophage-CSF, granulocyte/macrophage-CSF (GM-CSF), and Con A and tested for the production of IL-1 inhibitor. Production of IL-1 inhibitor was detected in cell supernatant, when H-161 cells were differentiated to adherent macrophage-like cells under the influence of PMA followed by a second signal provided by GM-CSF. Treatment of the other two cell lines, AML-193 and HL-60, with PMA plus GM-CSF also yielded similar IL-1 inhibitor protein. Partial purified H-161-derived IL-1 inhibitor showed specific binding to IL-1R-bearing cells and blocked the binding of IL-1 to its receptor and is thus similar to the urinary-derived molecule. We conclude the GM-CSF provides a signal to adherent macrophage-like cells to become "inhibitory macrophages" and to produce a competitive inhibitor of IL-1.
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PMID:Human granulocyte-macrophage colony-stimulating factor plus phorbol myristate acetate stimulate a promyelocytic cell line to produce an IL-1 inhibitor. 214 81

Tumor necrosis factor alpha (TNF-alpha) and gamma-interferon (IFN-gamma) have been shown to suppress clonogenic growth in cultures containing blast cells obtained from patients with acute myeloid leukemia. We report that recombinant human TNF-alpha and IFN-gamma are also able to induce functional and morphological maturation in fresh myeloid leukemic cells in vitro. Assessing suspension cultures containing cells from patients with acute myeloid leukemia (11 patients) or myeloid blast crisis of chronic myeloid leukemia (5 patients), it was found that recombinant human TNF-alpha and IFN-gamma significantly enhanced the number of cells reducing nitroblue tetrazolium, as compared to control cultures containing no cytokine (P less than 0.001 and P less than 0.001, respectively). Cells from responders showed alterations characteristic of monocyte/macrophage differentiation, adherence to plastic surfaces, development of positive staining for alpha-naphthyl acetate esterase, typical morphology, and expression of cell surface antigens detected by the monoclonal antibodies Mo-1, Mo-2, and My-4. Both cytokines decreased the number of viable cells, the number of blast cells, and the number of cluster-forming units in suspension culture, suggesting inhibitory actions on the growth capacity of leukemic cells. Compared to the maximum effects of either factor alone, the combination of recombinant human TNF-alpha and IFN-gamma significantly increased the extent of growth inhibition and cell adherence but did not result in further increases in nitroblue tetrazolium reduction. The presence of Auer rods in IFN-gamma or TNF-alpha differentiation-induced macrophages with cells from a patient with M5 acute myeloid leukemia demonstrates that these cytokines can induce differentiation of a leukemic clone in primary cells from patients with leukemia.
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PMID:Differentiation-inducing effect of recombinant human tumor necrosis factor alpha and gamma-interferon in vitro on blast cells from patients with acute myeloid leukemia and myeloid blast crisis of chronic myeloid leukemia. 249 71

gamma-Interferon (IFN-gamma) has previously been found to induce monocytic differentiation in established leukemic cell lines, such as HL-60 and U937. The aim of the present study was to evaluate the differentiative effect of highly purified recombinant (r)IFN-gamma on fresh bone marrow cells from patients with acute nonlymphocytic leukemia (n = 11) or myelodysplastic syndromes (n = 3). Blast cells were cultured in suspension in the presence or absence of rIFN-gamma (10-10(3) U/ml). While 6 out of 14 cases were unresponsive to rIFN-gamma in vitro, the remaining 8 patients showed a significant increase (0.05 greater than p greater than 0.001) in the percentage of cells expressing C3bi receptors, detected by OKM1 (median value in control cell, 9.5; median value in rIFN-gamma-treated cells, 31) and Mo1 (8.5 vs. 36), and in the percentage of cells expressing the monocytic antigens detected by Mo2 (8 vs. 28) and MY4 (6.5 vs. 32.5). In the responsive patients morphologic changes consistent with monocytic maturation, as well as a strong increase of alpha-naphthyl acetate esterase activity and of nitroblue tetrazolium reducing capability were observed upon culture with rIFN-gamma. We conclude that (a) rIFN-gamma may induce in vitro monocytic differentiation of blasts from acute nonlymphocytic leukemia and myelodysplastic syndrome patients, and that (b) this agent should be investigated for its capacity to be active in vivo.
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PMID:Recombinant gamma-interferon induces in vitro monocytic differentiation of blast cells from patients with acute nonlymphocytic leukemia and myelodysplastic syndromes. 312 8

The effect of recombinant human tumor necrosis factor alpha (rTNF-alpha) on human myelogenous leukemia clonogenic cells growing either in semisolid media or in suspension cultures was studied and compared with the effect on normal granulocyte-macrophage progenitors (GM-CFC). Exposure of cells to a range of rTNF-alpha doses including pharmacologically achievable plasma concentrations revealed a large heterogeneity in the response of leukemic clonogenic growth to rTNF-alpha. Only one of 13 specimens was highly resistant to rTNF-alpha. Eight of ten leukemic samples were significantly more sensitive than were normal GM-CFC, particularly within the in vivo achievable dose range (1 x 10(0) to 1 x 10(2) ng/mL). No significantly increased inhibition of either normal or leukemic clonogenic growth could be achieved by increasing the rTNF-alpha concentration above 250 ng/mL. Proliferation of leukemic clonogenic cells (L-CFC) was studied in suspension cultures. In five cases the clonogenic cells were significantly inhibited by rTNF-alpha while in one case no inhibition was observed. The inhibition of L-CFC growth by rTNF-alpha was dose dependent between 1 x 10(0) and 1 x 10(2) ng/mL. In suspension cultures, the TNF effect on L-CFC was a function of time of exposure, particularly with low concentrations of TNF. A remarkably higher inhibition of L-CFC as compared with the total leukemic population was observed in suspension cultures. Stimulation of L-CFC growth by rTNF-alpha was not observed. Normal GM-CFC were inhibited by alpha and gamma interferons (INF-alpha, -gamma) in a dose-related manner, with higher sensitivity of colonies than clusters. The response of GM-CFC to combination of recombinant IFNs and TNF was influenced by the size of clones scored and the source of colony-stimulating activity. The response of L-CFC to recombinant IFN-alpha and/or -gamma was highly variable, and sensitivity to one of the lymphokines did not predict for sensitivity to another. The response of L-CFC to combinations of rTNF-alpha and either IFN-alpha or IFN-gamma was complex, varying from synergistic to additive and indifferent. In three of six specimens, IFN-gamma acted antagonistically with rTNF-alpha, a phenomenon not observed with IFN-alpha. These observations suggest that the action of rTNF-alpha in acute myelogenous leukemia could be exploited therapeutically and the dose-time-response relationship should be considered in designing treatment schedules.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Antileukemic effect of recombinant tumor necrosis factor alpha in vitro and its modulation by alpha and gamma interferons. 313 64

One of 8 to 12 pre-B ALL cells co-express CD13 and CD33 antigens, but such blasts do not express myeloperoxidase (MPO) even on electronmicroscopy or mRNA. MPO+ pre-B ALL is extremely rare (1/50-1/100), however a cell-line (Tahr87) was established in culture. In contrast, T-lineage blasts express CD13/33 antigens regularly in the pro-thymic stage (CD7+ 5+ 2+ 3- 4- 8- or more immature), and a limited expression of MPO is rather commonly detected particularly in recurrences. The co-expression of CD3 epsilon/MPO or CD3 epsilon/delta/MPO mRNA has been demonstrated. Thus, the regulation of MPO expression is of utmost importance in interpreting the phenotypes of leukemia/lymphoma. While testing the effects of several cytokines on MPO expression, IFN-gamma was found to suppress the gene expression of MPO in HL60 cells. This suppression was not accompanied by differentiation, termination of proliferation or reduction of cytochemical MPO+ cells, and was reversible. Among 22 cases of M1 AML blasts, 8 cases were HLA-DR(-). DR antigen was induced by the presence of a mixture of IFN-gamma, TNF-alpha and TPA in 4 cases, but not in the other 4 cases. The blasts of the latter 4 cases were always CD34(-), CD7(-) and CD45RA-/RO+, and constituted a distinct M1 subset which has not previously been reported.
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PMID:[Cytokine in phenotypic analysis of leukemia/lymphoma: suppression of gene expression of myeloperoxidase by IFN-gamma and subset of AML M1 defined by CD45RO+/RA-, CD7(-), CD34(-) and non-inducible HLA-DR antigen]. 768 32

Modulation of expression of the c-kit proto-oncogene product, the receptor for the recently identified stem cell factor, was studied on 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated cultures of CD34+ normal bone marrow progenitor cells, blast cells from patients with primary acute myelogenous leukemia, cells from the leukemia cell lines HEL and MO7E, as well as cultured HMC-1 mast cells. Expression of c-kit was assessed on both RNA and protein level employing standard Northern blotting, reverse transcription, and polymerase chain reaction-based Southern blotting, as well as cell surface labeling with anti-c-kit mAb YB5.B8. Treatment of virtually all cell types with nontoxic concentrations of TPA (10(-9) M) for at least 48 h was associated with down-regulation of synthesis of c-kit transcripts and stem cell factor-receptor surface expression. Studies on the mechanism of action of TPA utilizing the HEL erythroleukemia line showed that TPA was primarily acting by accelerating the turnover of c-kit RNA most likely through induction of a destabilizing protein. The effect of TPA on c-kit expression levels was independent of TPA-mediated induction of differentiation since other compounds including IFN-gamma, vitamin D3, retinoic acid, arabinofuranosylcytosine, butyric acid, and camptothecin, which also effectively induced differentiation of HEL cells, failed to alter levels of c-kit expression.
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PMID:Phorbol ester 12-O-tetradecanoylphorbol-13-acetate down-regulates expression of the c-kit proto-oncogene product. 768 5

The activation of autologous cytotoxic cells by interleukin-2 (IL-2) may be a promising tool for elimination of minimal residual blast populations in patients with acute myelocytic leukemia (AML) to prolong disease-free survival. Here, we report the results of a phase II study using IL-2 for consolidation therapy in patients with second remission of de novo AML. All patients in 1st relapse of AML received a uniform induction therapy consisting of intermediate high-dose AraC (iHDAraC) 2 x 600 mg/m2 d1-4 and VP-16 100 mg/m2 d1-7. Patients achieving 2nd remission were treated with 4 cycles recombinant IL-2 (rIL-2) 9 x 10(6) IU/m2 administered on d1-5 and 8-12/cycle as 1h infusion every six weeks. In 37/66 (56%) evaluable patients, complete remission (CR) was achieved. So far, 21/37 patients (4 after additional autologous bone marrow transplantation (ABMT) received rIL-2 consolidation. Three patients are too early for evaluation, 4 received allogeneic BMT, 6 relapsed before IL-2 was scheduled and 4 refused treatment with rIL-2. The median disease-free survival (DFS) was 11 (4-49+) months. Up to now, in 5/21 (24%) patients the duration of 2nd remission exceeded that of 1st remission 7/21 (33%) are in ongoing 2nd remission (7+ to 49+ months). The side effects of rIL-2 were generally moderate and manageable. Only in two patients, previously treated with ABMT, severe side effects occurred; septicaemia and pneumonia in one patient and desquamative erythrodermia in the second one. In accordance with other studies rebound lymphocytosis with a marked increase of CD56(+)-cells and release of secondary cytokines such as TNF-alpha, IFN-gamma and IL-6 was observed. The schedule is feasible and the data suggest a possible benefit for DFS, which, however has to be confirmed by randomized trials.
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PMID:Interleukin-2 bolus infusion as late consolidation therapy in 2nd remission of acute myeloblastic leukemia. 771 35

HL-60 cell lines and AML fresh bone marrow cells were incubated with rhTNF-alpha and rhIFN-gamma in suspension culture system. Then total RNA was prepared for dot blot with 32P nick-translated c-myc DNA probe. The expression changes of c-myc oncogene when the HL-60 cell lines were treated with rhTNF-alpha and IFN-gamma and the AML fresh bone marrow cells treated with rhTNF-alpha alone were observed. The results showed that when the HL-60 cells were treated with 100U/ml or 500U/ml IFN-gamma and 50U/ml rhTNF-alpha for 8 hours, the expression of c-myc oncogene can be inhibited remarkably. The combination of rhIFN-gamma and rhTNF-alpha shows synergistic effect on inhibition of c-myc expression. High expression of c-myc was found in 8 patients with AML; c-myc mRNA level decreased remarkably after treatment of fresh bone marrow cells with 50U/ml rhTNF-alpha for 12 hours in 6 cases, while the remaining 2 cases showed minimal changes. The results demonstrate that rhTNF-alpha have inhibitive effect on c-myc expression in HL-60 cells and AML fresh leukemic cells. It also indicates the possibility of treating AML with low-dose rhTNF-alpha.
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PMID:[Inhibition of proto-oncogene c-myc expression with recombinant human tumor necrosis factor-alpha and interferon-gamma in HL-60 cell lines and acute myelocytic leukemic fresh cells]. 783 39

The MTT-colorimetric monocyte mediated cytotoxicity assay, based upon the ability of living cells to reduce 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT) into formazan, was evaluated using leukemic cells from five representative human leukemic cell lines and from 28 patients with acute myeloid leukemia (AML). An excellent linearity between absorbance and leukemic cell number was observed up to 5 x 10(4) cells/well and 50 x 10(4) cells/well for all cell lines and patients samples tested, respectively, in a 96-wells microtiter culture system. A huge variability in the susceptibility of leukemic cells to purified and IFN-gamma-activated human monocytes could be observed at effector-to-target cell (E:T) ratios of 1. The mean signal-to-noise ratio of the MTT assay for monocyte-leukemic cell mixtures from patients was 2.69 +/- 0.39 at E:T 1. In conclusion, the MTT based monocyte mediated cytotoxicity assay should be useful for studying the susceptibility of a variety of leukemic cells from cell lines and from patients with AML to monocytes in a rapid, sensitive and semi-automated manner.
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PMID:A tetrazolium-based colorimetric MTT assay to quantitate human monocyte mediated cytotoxicity against leukemic cells from cell lines and patients with acute myeloid leukemia. 808 35


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