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)

Changes in the localization of terminal transferase during the cell cycle in random cultures of human pre-T leukemia line RPMI-8402 were examined by light and electron microscopy on immunoperoxidase-stained preparations. Paraformaldehyde-fixed and saponin-permeabilized human cells were used with a monoclonal anti-human terminal deoxynucleotidyl transferase (TdT) primary reagent to demonstrate changes in enzyme distribution occurring between interphase and mitosis. Nuclear localization is found uniformly during interphase. At metaphase, however, the majority of TdT staining appears randomly distributed in the cytoplasm and traces of TdT staining remain associated with mitotic chromatin. At later phases, when the daughter cells are forming, the enzyme again appears to be restricted to the new nuclear structure.
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PMID:Intracellular localization of terminal transferase during the cell cycle. 139 93

The effect of reduced and oxidized folates on the development of methotrexate (MTX) resistance has been examined in human leukemia cell line K562 (K562/S). K562/S cells were made resistant to MTX by soft-agar cloning either in RPMI-1640 medium (K562/MTX-PGA) or in folic-acid-free RPMI-1640 medium containing 10 nM leucovorin (K562/MTX-LV). The optimal concentrations of leucovorin for the growth of K562/S, K562/MTX-PGA and K562/MTX-LV cells were 1 nM, 5 nM and 10 nM respectively. K562/MTX-PGA cells were 24-fold resistant to MTX as noted by impaired MTX transport. In contrast, K562/MTX-LV cells were 26-fold resistant to MTX as noted by gene amplification of dihydrofolate reductase. Furthermore cross-resistance to cytosine arabinoside was only demonstrated in K562/MTX-PGA, while the K562/MTX-LV cells showed no significant cross-resistance to cytosine arabinoside. These results suggest that the type and level of folates used during the development of MTX resistance may play a role in the mechanism for MTX resistance. Leukemia cells that are grown in leucovorin might serve as a model for acquired MTX resistance in vivo.
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PMID:The role of folates in the development of methotrexate resistance in human leukemia cell line K562. 142 25

Monoclonal antibodies (mAbs) of IPO series were developed following immunization with human B cell lines RPMI-1788, Daudi, and spleen cells from a patient with hairy cell leukemia. Reactivity of these mAbs was studied on 19 human cell lines, mononuclear cells of 50 healthy persons and 142 patients with leukemias and lymphomas. It was shown that mAbs IPO-3, IPO-10 and IPO-24 define B cell-specific antigens expressed at different stages of maturation. MAb IPO-3 reacted with activated B lymphocytes. MAb IPO-10 defined the antigen which appears on B cell progenitors following HLA-DR and proceeding CD19, CD10, CD22, CD37; cy mu and CD20 and have been lost during terminal differentiation. The antigen detected by mAb IPO-24 was expressed throughout B cell ontogeny from pre-B cell until the B-blasts. MAb IPO-4 detected an antigen of activated T and B lymphocytes. These mAbs are useful tools in the leukemia and lymphoma phenotypic characterization and classification.
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PMID:Monoclonal antibodies of IPO series against B cell differentiation antigens in leukemia and lymphoma immunophenotyping. 152 2

The (-) - (R) - 2-aminomethylpyrrolidine (1, 1-cyclobutanedicarboxylato) platinum(II) monohydrate, DW A2114R, is a new derivative of cis-dichlorodiammineplatinum(II), CDDP, which is reported to have a lower nephrotoxicity than CDDP. In this report, we investigated the effects of DW A2114R, in comparison with CDDP, on the cell growth, the cell cycle traverse and the colony-forming ability of human leukemia RPMI 8402 cells in vitro. The inhibitory effects of DW A2114R on the cell growth and the colony-forming ability were about 1/10 and 1/10-1/30, respectively, of the CDDP dose. And DW A2114R showed a higher time-dependency than CDDP in the experiment comparing exposure time to the drugs. Analysis of DNA histograms obtained by flow cytometry revealed that DW A2114R had a similar effect on the cell cycle traverse to that of CDDP. Both drugs exerted their growth-inhibitory effect by blocking cells at G2 phase. At higher concentrations, they prolonged the traverse of cells through S phase and completely inhibited them throughout the cell cycle. The comparative study on the colony-forming ability suggested that the G2 phase accumulation was irreversible and that these drugs are lethal, so the G2 phase accumulation could be considered a cytocidal effect of the drugs. In early clinical studies, however, the dose of DW A2114R was put at about 15-fold higher than the therapeutic dose of CDDP. This was comparable with our results in vitro and DW A2114R showed a much lower toxicities, with special regard to nephrotoxicity, than CD DP. These clinical data and our results suggest that DW A2114R could be clinically effective as an antitumor agent.
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PMID:[Flow cytometric analysis of the effect of DWA2114R on the cell cycle traverse of RPMI 8402 cells--comparison with CDDP]. 155 96

The constitutive expression of 25-hydroxyvitamin D3-24-hydroxylase (25-(OH)D3-24-hydroxylase) activity has been studied in an adherent variant (Ad-HL60) of the human promyelomonocytic leukaemia cell line HL60. The Ad-HL60 cells have a more differentiated phenotype than the non-adherent cells from which they were derived, and synthesized 1.88 +/- 0.07 (+/- S.E.M.) pmol 24,25-(OH)2D3/h per 10(6) cells following culture in RPMI-1640 medium containing less than 0.02 nM 1 alpha,25-(OH)2D3. They also synthesized 1.66 +/- 0.05 pmol 24,25-(OH)2D3/h per 10(6) cells following culture in 1 alpha,25(OH)2D3-free medium supplemented with 1 g bovine serum albumin/l instead of 10% serum. In contrast, non-adherent HL60 cells required exposure to 10-100 nM 1 alpha,25-(OH)2D3 to induce equivalent 24,25-(OH)2D3 synthesis. The 25-(OH)D3-24-hydroxylase expressed by Ad-HL60 cells had an apparent Michaelis constant of 1 microM and maximal rate of 20 pmol/h per 10(6) cells with substrate concentrations from 0.012 to 1.2 microM/incubation (5-500 ng/ml). Furthermore, 24,25-(OH)2D3 synthesis was inhibited in a dose-dependent manner by ketoconazole (0.01-10 microM), suggesting that the enzyme is cytochrome P-450 dependent. Ad-HL60 cells expressed approximately 3500 specific receptors for 1 alpha,25-(OH)2D3/cell with a dissociation constant of 40 pM. Following exposure to 0.1-100 nM 1 alpha,25-(OH)2D3, Ad-HL60 cell proliferation was significantly inhibited compared with controls grown in medium containing less than 0.02 nM 1 alpha,25-(OH)2D3 for 96 h. Expression of 25-(OH)D3-24-hydroxylase was also inhibited in a dose- and time-dependent manner; however, expression of nonspecific esterase was not induced. Both of these findings are contrary to those previously demonstrated for non-adherent HL60 cells, whereas the dose-dependent inhibition of cell proliferation by 1 alpha,25-(OH)2D3 occurs in both adherent and non-adherent phenotypes. These observations on Ad-HL60 cells represent the first description of a cell type in which 1 alpha,25-(OH)2D3 appears to inhibit 25-(OH)D3-24-hydroxylase activity. The Ad-HL60 cells also constitutively metabolized 1 alpha,25-(OH)2D3 in a manner consistent with formation of 1 alpha,25-(OH)2D3 without previous exposure to 1 alpha,25-(OH)2D3. In contrast, many other cell types, including non-adherent HL60 cells, require exposure to 1 alpha,25-(OH)2D3 to induce metabolism of 1 alpha,25-(OH)2D3 to 1 alpha,24,25-(OH)3D3, a reaction that represents the initial step for catabolism of 1 alpha,25-(OH)2D3 to calcitroic acid.
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PMID:Studies on an adherent variant of the human promyelomonocytic HL60 leukaemia cell line that constitutively expresses 25-hydroxyvitamin D3-24-hydroxylase activity which is inhibited by 1 alpha,25-dihydroxyvitamin D3. 177 40

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

A total of 72 human leukemia-lymphoma cell lines were studied for reactivity with the monoclonal antibody (MAb) A7, an anti-human colon-cancer-cell-associated antigen reagent, by indirect membrane immunofluorescence. Nine of the 72 cell lines expressed the antigen recognized by A7 MAb. Five of the 34 T-cell lines, 2 of the 21 B-cell lines, and 2 of the 3 non-lymphoid-non-myeloid cell lines were reactive with A7 MAb. By means of SDS-PAGE and immunoblotting, the antigens isolated from both colon cancer cell lines (WiDr, SW1116 and LoVo) and leukemia cell lines (A3/KAWAKAMI, H9, RPMI 8226 and SPI-801) showed an identical MW of 42-43 kDa. The non-glycosylated antigen recognized by A7 MAb, which was expressed on both the colon cancer line (SW1116) and the leukemia line (H9) in the presence of tunicamycin, also showed an identical MW of 36 kDa. However, the quantity of the antigen in the leukemia cells was significantly lower than in the colon cancer cells. Although expression of this colon-cancer-associated antigen in the non-colon cancer cells is real, the significant expression of this antigen in colon-cancer cells makes it useful for clinical monitoring of colon cancer patients.
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PMID:Identification and characterization of a colon-cancer-associated antigen expressed on leukemia-lymphoma cell lines. 199 51

A new human leukemia cell line, designated as ME-1, was established from the peripheral blood leukemia cells of a patient with acute myelomonocytic leukemia with eosinophilia (M4E0). This cell line has the characteristic chromosome abnormality of M4E0, inv(16) (p13q22). When cultured in RPMI 1640 medium containing 10% fetal calf serum, ME-1 cells were monoblastoid, but with the addition of cytokines such as interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-4, or medium conditioned by phytohemagglutinin-stimulated human peripheral leukocytes (PHA-LCM), the cells exhibited differentiation to macrophage-like cells. PHA-LCM also promoted eosinophilic-lineage differentiation of this cell line, although IL-5 did not do so. To elucidate the mechanism of proliferation and differentiation of ME-1 cells, we studied the effect of a potent inhibitor of protein kinase C, 1-(5-isoquinolinyl-sulfonyl)-2-methylpiperazine (H-7), on colony formation of ME-1 cells. H-7 inhibited colony formation of ME-1 cells by IL-3 or GM-CSF dose dependently, but had little inhibitory effect on colony formation by IL-4. These results indicate that the proliferation and differentiation of ME-1 cells by IL-3 or GM-CSF were related to the activation of protein kinase C, while those by IL-4 involved other regulatory systems. ME-1 cells should be useful for studying the pathogenesis of M4E0 and the mechanisms of proliferation and differentiation of leukemic and normal progenitors by cytokines.
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PMID:Establishment and characterization of a new human leukemia cell line derived from M4E0. 207 80

A eukaryotic growth medium (Program Development Research Group Basal Growth Medium) was developed for CO2-independent maintenance and propagation of human and nonhuman tumor cell lines representing diverse histologies (e.g., cancers of the brain, colon, lung, ovary, and kidney, as well as leukemia and melanoma). It was also shown to be suitable for the maintenance and propagation of nontumor cells of human and nonhuman derivation. The medium derives its buffering capacity primarily from beta-glycerophosphate, exhibits a stable physiologic pH of 7.3-7.4, and is optimized to facilitate growth in atmospheric CO2. It is also useful in cellular growth and cytotoxicity assays based on either the metabolic reduction of tetrazolium reagents or protein staining. The 50% inhibitory concentration values obtained with carmustine, doxorubicin, and tamoxifen in cell lines maintained in the new medium under atmospheric CO2 were closely comparable to those obtained with these drugs against cells maintained in RPMI-1640 under a 5% CO2 environment.
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PMID:New carbon dioxide-independent basal growth medium for culture of diverse tumor and nontumor cells of human and nonhuman origin. 211

The authors have developed a panel of monoclonal antibodies (MCA) of IPO series (Institute of Problems of Oncology, Kiev). RPMI-1788 cell line, Daudi, as well as splenocytes of a patient with hairy-cell leukemia were used for immunization of mice. It has been shown that IPO-3, IPO-10 and IPO-24 MCA are directed against differentiation antigens of human B-lymphocytes. IPO-4 MCA reveal the antigen of activated T- and B-cells. IPO-5 and IPO-20 MCA recognize HLA-ABC, while IPO-37 a common leucocytic antigen. IPO-38 MCA are directed against the nuclear antigen. The possibilities of using IPO MCA in hematology have been discussed.
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PMID:[Monoclonal antibodies of the IPO series in studying and diagnosing malignant lymphoproliferative diseases]. 237 43


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