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

Expression of three clones (6-1E, 7-3G and 9-5C) selected from a chronic lymphocytic leukemia cDNA library was studied by nucleic acid hybridization in human promyelocytic leukemia cells (HL-60) treated with chemical inducers of cell differentiation and in primary cells derived from 27 patients with leukemia or myelodysplastic syndrome. The differentiation of HL-60 cells into macrophage-like cells upon induction by 12-0-tetradecanoyl phorbol-13-acetate (TPA) was accompanied by rapid induction of the expression of 6-1E and 7-3G genes. The levels of expression of the 9-5C gene were not altered during macrophage-monocytic or granulocytic differentiation of HL-60 cells. The expression of the 6-1E and/or 7-3G gene was induced by TPA in four of 6 samples derived from patients who achieved complete remission, but not in any of the acute nonlymphocytic leukemia samples from patients who failed to achieve complete remission. These findings suggest that expression of the 6-1E and 7-3G genes is related to macrophage-monocytic differentiation and that alterations of these gene expressions in fresh leukemia cells after one hour of TPA treatment are of prognostic significance in predicting the response to therapy.
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PMID:Expression of selected genes in differentiated HL-60 cells and primary cells from human leukemias. 233 84

The possible presence of tumor cells in remission bone marrow (BM) is one of the major problems for the success of autologous BM transplantation (ABMT), because the reinfusion of viable malignant cells may result in relapse. In this study we attempted the purging of the malignant cells by the use of VP-16-213 (VP-16) and nitrogen mustard (NM) either alone or in combination. Four cell lines from various hematological malignancies were utilized: SK-DHL-2 was established from a B-cell diffuse histiocytic lymphoma; RAJI was from an Epstein-Barr virus (EBV)-infected B-cell lymphoma cell line; K-562 were from a chronic myelogenous leukemia (CML) blastic crisis; and HL-60, derived from a human promyelocytic leukemia, were used in exponential growth phase. Four logs of tumor cell-elimination were observed after 1-h incubation of RAJI cells with 25 micrograms/ml of VP-16. K-562 and SK-DHL-2 cells showed a greater than 4 logs reduction after 1-h exposure to 75 micrograms/ml of VP-16, and HL-60 cell line growth was inhibited by 3.2 logs. Under the same conditions (i.e., the treatment with 75 micrograms/ml), we observed a mean recovery of 2.7% of BM granulocyte-macrophage colonies (granulocyte-macrophage colony-forming units, CFU-GM), 3.2% of erythroid (erythroid burst-forming units, BFU-E), and 2.5% of pluripotent (granulocyte erythrocyte macrophage megakaryocyte colony-forming units, CFU-GEMM) progenitors, respectively. More than 3 logs reduction of leukemia and lymphoma cell lines were reached following 1-h treatment with 1 micrograms/ml of NM. After exposure to the same concentration of the drug we obtained 2.5% CFU-GM, 1.2% BFU-E, and 2% CFU-GEMM recovery. A drug mixture containing constant doses of VP-16 (10 and 20 micrograms/ml) and NM (1 micrograms/ml) reduced HL-60 and SK-DHL-2 cell growth to undetectable levels (i.e., 4 and 5 logs elimination) in the presence of an excess of irradiated BM cells, whereas it did not further affect the recovery of the BM precursors as compared to the single drugs used alone. These results suggest that the combination of these two drugs at the selected dose level could provide a better therapeutic index (i.e., higher tumor cell killing coupled with no additional cytotoxic effect on normal BM cells) than the same chemotherapeutic agent used alone and that this mixture may be useful for the "ex vivo" treatment of BM grafts.
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PMID:In vitro cytotoxicity of VP-16-213 and nitrogen mustard: agonistic on tumor cells but not on normal human bone marrow progenitors. 239 48

The active metabolite of vitamin D known as 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] is a major physiologic regulator of mineral metabolism in man. The compound is also a potent inducer of differentiation of a human promyelocytic leukemia cell line known as HL-60. The induction of differentiation of myeloid leukemia cells to functional end cells offers an appealing therapeutic prospect. We investigated the ability of 1,25(OH)2D3 both to induce in vitro the differentiation of blast cells taken from patients with acute myelogenous leukemia and to improve hematopoiesis in vivo in patients with the myelodysplastic syndromes (preleukemia). We found that high concentrations (10-6 M) of 1,25(OH)2D3 significantly induced the in vitro differentiation of blast cells as measured by morphology, phagocytosis, and superoxide production. A concentration of 10-9 M 1,25(OH)2D3 had no effect on blast cell differentiation. We gave 2 microgram/day of 1,25(OH)2D3 to 18 patients with myelodysplastic syndrome (preleukemia) in an attempt to improve their hematopoiesis. During therapy, their peak peripheral blood granulocyte, platelet, and macrophage concentrations were slightly elevated as compared to their baseline, starting levels. Eight patients had a partial or minor peripheral blood response to the compound during the administration of 1,25(OH)2D3. However, no patient showed significant improvement of peripheral blood cell or marrow blast cell counts by the end of the study (greater than or equal to 12 weeks) as compared to their starting levels. Seven of the patients developed leukemia before or by 12 weeks of treatment. Nine of the 18 patients developed hypercalcemia. Taken together, the study shows that high concentrations (10-6M) of 1,25(OH)2D3 can induce differentiation of leukemia blast cells in vitro, but the administration of 1,25(OH)2D3 to patients with the myelodysplastic syndromes (preleukemia) does not have an enduring therapeutic effect. Hypercalcemia prevented administering greater amounts of 1,25(OH)2D3. In the future, the use of new vitamin D analogs that induce hematopoietic cell differentiation without inducing hypercalcemia might allow the achievement of higher blood levels of the inducing compound and might be medically useful for selected preleukemic and leukemic patients.
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PMID:1,25-Dihydroxyvitamin D3: in vivo and in vitro effects on human preleukemic and leukemic cells. 241 38

About 1.5% of phosphorylated amino acid residues of HL-60 promyelocytic leukemia cells are phosphotyrosine. Induction of granulocytic differentiation by exposure to dimethylsulfoxide decreased tyrosine phosphorylation to 0.2%. A maximum 3-fold increase in tyrosine kinase activity and a 7-fold increase in protein phosphotyrosine phosphatase activity accompanied this change. Monocytic differentiation induced by 12-O-tetradecanoylphorbol-13-acetate, caused a decrease in phosphotyrosine levels to 0.1%; tyrosine kinase activity maximally increased 2-fold, and protein phosphotyrosine phosphatase activity increased 11-fold in these differentiated cells. Thus, although total tyrosine kinase activity markedly increased during differentiation, this was counteracted by an even greater elevation in protein phosphotyrosine phosphatase activity. The findings support the concept that tyrosine phosphorylation is important in the regulation of growth and differentiation of leukemia cells.
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PMID:Regulation of protein phosphotyrosine content by changes in tyrosine kinase and protein phosphotyrosine phosphatase activities during induced granulocytic and monocytic differentiation of HL-60 leukemia cells. 243 May 65

Treatment with a combination of daunorubicin (45 mg/m2 IV, days 1-3) and cytarabine (100 mg/m2 continuous IV infusion, days 4-10) failed to induce complete remission in 31 of 87 children (36%) with acute nonlymphocytic leukemia (ANLL). Six patients with monocytic or promyelocytic leukemia died before day 14 of therapy from complications of hyperleukocytosis and coagulopathy; an additional 10 failed because of fatal infections associated with drug-induced marrow hypoplasia, and the remaining 15 had residual leukemia despite receiving two courses of daunorubicin and cytarabine. Alternative therapy with etoposide (250 mg/m2, IV, days 1-3, 7-9) and 5-azacytidine (300 mg/m2 IV, days 4, 5, 9, 10) induced complete remission in nine (60%) of the 15 patients with resistant leukemia. Among the six children who failed to respond to either regimen, three had cytochemical and immunophenotypic features indicative of acute mixed-lineage leukemia, and one had monosomy 7 syndrome. Our findings suggest that the addition of etoposide and 5-azacytidine to a basic daunorubicin-cytarabine regimen would increase remission induction rates in childhood ANLL. Careful determination of pretreatment characteristics, including blast cell immunophenotype and cytogenetic properties, are needed to identify unusual cases of ANLL that may require selective therapy.
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PMID:Induction failures in childhood acute nonlymphocytic leukemia: etoposide/5-azacytidine for cases refractory to daunorubicin/cytarabine. 243 Dec 55

A growth-inhibitory (GI) factor, that specifically inhibits the growth of mouse monocytic leukemia cells, was found in conditioned medium of mouse lung tissue, but not in that of mouse brain, heart, liver, or kidney tissue. Conditioned medium of spleen or bone marrow cells had low GI activity. Pulmonary macrophages were as active as peritoneal and bone-marrow-derived macrophages in production of the GI activity. The GI factor inhibited the growth of murine monocytic leukemia cell lines Mm-A and J774.1, but scarcely inhibited the growth of other mouse cell lines, such as a myeloblastic leukemia cell line (M1), a Friend erythroleukemia cell line (745A) and a mammary carcinoma cell line (FM3A). It had no significant effect on the growth of human monocytic leukemia cell lines U937 and THP-1 or on the HL-60 promyelocytic leukemia cell line. These results suggest that the GI factor produced by mouse lung tissue preferentially inhibits the growth of mouse monocytic cells. The GI factor was found to be a proteinaceous substance with a molecular mass of 25 kDa. On chromatofocusing, the GI activity was eluted with Polybuffer 96/acetic acid at pH 7.2-7.5. The GI activity was not significantly decreased by heat treatment at 56 degrees C for 30 min or acid treatment (0.01 M HCl, 14 h), but the GI activity in glycosidase-treated conditioned medium of lung tissue was lost on heat treatment. The GI activity could not be neutralized with anti-(interferon alpha + beta) antibody. The activity was produced constitutively by lung tissues and its production was not stimulated appreciably by lipopolysaccharide, lectin, or poly(I).poly(C). The GI factor appears to be a cytokine unrelated to known cytokines such as tumor necrosis factor, interleukin-1, transforming growth factor beta, and interferons. These results suggest that the GI factor may be involved in negative feedback regulation of macrophage production in steady-state conditions in the lungs.
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PMID:Normal mouse lung tissue produces a growth-inhibitory factor(s) preferential for mouse monocytic leukemia cells. 248 Aug 47

The human cell surface protein CD4 is not only an important accessory molecule in the activation of MHC class-II-restricted T cells, but has also been implicated to be a receptor for the human immunodeficiency virus HIV-I on lymphoid and monocytic cells. We have found that a 24-h treatment of the promonocytic leukemia cell line U937 with rIFN-gamma decreases the expression of the CD4 Ag by 50% as measured by cytofluorographic analysis. The decrease in CD4 expression was dependent on the concentration of rIFN-gamma, with maximal effects occurring at 20 to 200 U/ml. The decrease appeared to be due to actual loss of the CD4 molecule from the cell surface rather than masking of a particular epitope, inasmuch as similar results were obtained with the OKT4 and OKT4A antibodies. The effect of rIFN-gamma to decrease CD4 expression was not due to a general loss of cell surface Ag, because the binding of OKM1 and anti-HLe-1 increased after rIFN-gamma treatment. Treatment of rIFN-gamma also decreased cell surface CD4 expression on the promyelocytic leukemia cell line HL-60, and on the monocytic cell line THP-1, although the extent of the decrease was less than on U937 cells. Freshly isolated normal peripheral blood monocytes treated for 48 h with rIFN-gamma bound much less OKT4 or OKT4A antibody than cells incubated in the absence of rIFN-gamma. Moreover, treatment with rIFN-gamma reduced the percentage of peripheral blood monocytes that were positive for the CD4 Ag. In contrast with the decrease in CD4 levels on rIFN-gamma-treated monocytes, treatment with rIFN-gamma had no effect on CD4 levels on peripheral blood T lymphocytes or T cell lines.
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PMID:Treatment with recombinant IFN-gamma decreases cell surface CD4 levels on peripheral blood monocytes and on myelomonocyte cell lines. 249 48

The in vitro induced differentiation of a number of human leukemia cell lines by chemical inducers not only provides a valuable model system for the study on the mechanism of hematopoietic cell proliferation and differentiation at both cellular and molecular levels, but also reveals a new prospect in the treatment of leukemia. In order to find out the possibility of applying inducing agents to the patients with various types of leukemia, the bone marrow cells in primary culture from 50 patients with leukemia were tested for their inducibility in response to the inducers. Only M3 leukemia bone marrow cells can be markedly induced by retinoic acid to the myeloid terminal cells with positive NBT reduction while the cells of other types respond with uncertainty. TPA is able to cause a macrophage-like differentiation in bone marrow cells of all types of leukemia except M1. However, the leukemic cells of chronic myelogenous leukemia in lymphocytic blast crisis will lose response to TPA. The cultured bone marrow cells of acute lymphocytic leukemia respond neither to retinoic acid nor to TPA. Homoharringtonine, a chemotherapeutic drug used in the so-called HOAP regimen for acute nonlymphocytic leukemia, seems to possess the capability of inducing HL-60, the promyelocytic leukemia cell line, to NBT positive myeloid terminal cells, although the inducing effect is weaker than retinoic acid.
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PMID:Heterogenous response of primary cultured bone marrow cells of patients with different varieties of leukemia to differentiation inducers. 250 3

Using [125I]I-S-145-OH, a radiolabeled derivative of a thromboxane (TX) A2 receptor antagonist, we have studied the expression of the TXA2 receptor in several lines of cultured leukemia cells. Specific binding of the ligand was observed in cells of two human erythroleukemia cell lines, K562 and HEL. However, only negligible binding was seen in HL-60 human promyelocytic leukemia cells and L-1210 murine leukemia cells. Scatchard analyses revealed a curvilinear plot which indicated the existence of two classes of binding sites in these cells. The Kd and Bmax values of the high and low affinity bindings in HEL cells were 2.4 nM and 24 fmol/10(6) cells, and 58 nM and 360 fmol/10(6) cells, respectively. These values in K562 cells were 2.8 nM and 16 fmol/10(6) cells, and 18 nM and 46 fmol/10(6) cells, respectively. The addition of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) to the cultures of K562 and HEL cells caused a concentration- and time-dependent increase in the binding activity. TPA at 10(-8) M increased the Bmax values of both high and low affinity bindings approximately 3 times without significant change in their Kd values and these increases were inhibited by the addition of actinomycin D. Both classes of the binding in cells of each cell line were specifically displaced by several TXA2/prostaglandin (PG) H2 analogues, although the relative specificities to the analogues were different in the two classes. These results suggest that both HEL and K562 cells express the TXA2 receptor on their cell surface and TPA strongly induces this expression in these cells.
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PMID:Expression of thromboxane A2 receptor in cultured human erythroleukemia cells and its induction by 12-O-tetradecanoylphorbol-13-acetate. 252 3

The rat promyelocytic leukemia cell line BNML is highly sensitive to cAMP elevating agents, and to cholera toxin (CT) in particular: 99.9% of the cells are killed in less than 48 hr of toxin treatment. We described here a subclone of the same leukemia, which, in contrast, is completely resistant to CT but still sensitive to other cAMP inducers. This locates the defect responsible for CT resistance at the membrane, somewhere between surface CT receptors and adenylate cyclase. CT-resistant BNML cells (CTR-BNML) do have surface CT receptors (several thousands per cell). Adenylate cyclase activity in CTR-BNML cells is not stimulated by cholera toxin. Other GS mediated stimulation of adenylate cyclase (by PGE, isoproterenol, histamine, NaF) remains relatively high, though 25-60% lower than in CTS-BNML cells. These results suggest that a specific adenylate cyclase defect is involved in the resistance of CTR-BNML cells to cholera toxin.
Leukemia 1989 Apr
PMID:Cholera toxin resistance associated with deficient adenylate-cyclase activity in a subclone of the rat promyelocytic leukemia (BNML). 253 85


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