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)

A case of WT31-, CD3+ large granular lymphocyte leukemia is reported. On surface marker analysis, the proliferating cells were found to be CD3+4-8-16+ and WT31-. By two-color immunofluorescence staining, CD3+4-8- cells were found to be WT31-, and a small population of WT31+ cells expressed either CD4 or CD8. WT31-, CD3+ cells were also identified in a bulk culture of lymphocytes expanded in vitro. Because WT31 monoclonal antibody (MoAb) reacts with the nonpolymorphic epitope of the disulfide-linked heterodimer of the T cell antigen receptor (Ti), the absence of the WT31-reactive Ti determinant may represent an expression of different CD3-associated polypeptides. The rearrangement of the Ti-beta and Ti-gamma genes but not the immunoglobulin gene was demonstrated, and the single pattern of rearrangement indicated the monoclonal origin of the lymphocytes. When the lymphocytes were assayed for their cytotoxicity against K562, MOLT-4, Daudi, and Raji tumor cell lines, a broad spectrum of cytotoxicity for these tumor cells was observed, and the lymphocytes also exhibited antibody- and lectin-dependent cellular cytotoxicity and lymphokine-activated killer activity. Treatment with anti-CD2 and anti-CD3 MoAbs inhibited their nonspecific cytotoxicity. The anti-CD3-mediated inhibition of nonspecific cytotoxicity suggested that an as yet unidentified Ti, present in association with the CD3 molecule on these lymphocytes, serves as a specific receptor for target tumor cell recognition.
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PMID:Ti (WT31)-negative, CD3-positive, large granular lymphocyte leukemia with nonspecific cytotoxicity. 296 5

An autocrine (noninterleukin 2) growth factor, which we term leukemia derived growth factor (LDGF), has previously been found in the culture supernatant of the human malignant T-lymphoid cell line MOLT-4f. We now show that two other human malignant T-lymphoid cell lines, CCRF-CEM and CCRF-HSB-2 also produce such a factor. All three factors, i.e., the LDGF from MOLT-4f, CCRF-CEM, and CCRF-HSB-2 are similar to each other both in biological activity and in physicochemical characteristics. In addition to their autocrine activity, these LDGFs stimulate the growth of other malignant T-lymphoid cell lines, but they do not stimulate B-lymphoblastoid or myeloid cell lines. The results therefore suggest that these LDGFs are T-cell specific.
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PMID:Leukemia derived growth factors produced by human malignant T-lymphoid cell lines. 308 Feb 40

The purified leukotoxin of Actinobacillus actinomycetemcomitans kills human leukemic cell lines (e.g., HL-60, U937, and KG-1) and human T- and B-cell lines (e.g., JURKAT, MOLT-4, Daudi, and Raji) in a dose- and time-dependent manner. The 50% effective doses for these cell lines are similar to those established for human polymorphonuclear leukocytes and monocytes. In contrast, other human and nonhuman tumor cell lines are not susceptible to the leukotoxin. These human leukemia and lymphoid cell lines will serve as useful model systems with which to study the molecular specificity and mechanism(s) of action of the actinobacillus leukotoxin.
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PMID:Killing of human myelomonocytic leukemia and lymphocytic cell lines by Actinobacillus actinomycetemcomitans leukotoxin. 325 84

After four days of treatment with 10(-8) M TPA, differentiation of the human T-lymphoblastoid cell line MOLT-4 was induced along the T cell lineage, confirmed by a fall in adenosine deaminase and 5'-ectonucleotidase and a rise in purine nucleoside phosphorylase activity. TPA-treated cells became resistant to the cytotoxic effects of 1-beta-D-arabinofuranosylcytosine (Ara-C), 9-beta-D-arabinofuranosyladenine (Ara-A), and 2-chlorodeoxyadenosine. This was, in part, due to the altered cell cycle distribution (accumulation of cells in the G1 phase), since the toxicity of Ara-C and Ara-A is S phase specific. The diminished rate of Ara-C transport concomitant with Ara-CTP formation after TPA treatment is considered to be the biochemical basis for this acquired resistance.
Leukemia 1988 Jul
PMID:Changes in sensitivity to anticancer drugs during TPA-induced cellular differentiation in a human T-lymphoblastoid cell line (MOLT-4). 326 Jun 48

We have recently shown that glucocorticoids dramatically increase the number of interleukin 1 (IL 1) receptors on human peripheral blood mononuclear cells (PBMC) and that IL 1 selectively induces the phosphorylation of a cytosolic 65-kilodalton (kDa) protein (pp 65) in glucocorticoid-pretreated PBMC. We describe here the purification and biochemical characteristics of pp 65. 32P-Labeled pp 65 was purified to homogeneity from the cytosol fraction of IL 1 stimulated [32P]orthophosphate-labeled PBMC by sequential chromatography on Sephacryl S-200, high-performance liquid chromatography (HPLC) anion exchange, and hydroxyapatite HPLC. The purified pp 65 was homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The unphosphorylated 65-kDa protein (p 65) was also purified to homogeneity in a similar way. About 40 micrograms of purified 65-kDa protein was recovered from 5 x 10(8) PBMC. Analysis of the amino-terminal sequence of the purified pp 65 revealed the amino terminus of pp 65 to be blocked. Amino acid sequence analysis of a cyanogen bromide cleaved peptide showed pp 65 to be a unique protein whose protein sequence has not yet been reported. Studies of the distribution of p(p) 65 based on Western blotting using specific polyclonal rabbit antibody to p(p) 65 showed that p(p) 65 exists in a variety of cells such as neutrophils, monocytes, B lymphocytes, and myeloid cells. It could not be detected in the T cell leukemia cell line (MOLT), melanoma cells, and fibroblasts.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Purification and characterization of a cytosolic 65-kilodalton phosphoprotein in human leukocytes whose phosphorylation is augmented by stimulation with interleukin 1. 326 3

Immunoglobulin samples (HIV-Ig) were prepared by cold ethanol fractionation of human plasma containing antibody against human immunodeficiency virus (HIV). The ability to prevent viral spreading was studied using either human T-cell leukemia virus type I (HTLV-I)-carrying MT-4 cells or in a coculture system using MOLT-4 cells and virus-producing MOLT-4/HIV HTLV-IIIB cells. Treatment of HIV-infected MT-4 cells with HIV-Ig effectively blocked the appearance of antigens of HIV and the virus-induced cytopathic effect. HIV-Ig blocked multinucleated giant cell formation in the MOLT-4 and MOLT-4/HIV HTLV-IIIB coculture system.
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PMID:Efficacy of an immunoglobulin preparation from HIV carriers in preventing HIV replication in vitro. 336 35

Single-cell analysis by flow cytometry has enabled us to analyze the effects of a phorbol ester and known tumour promoter, TPA, on the phenotypes of four tumour lines. TPA is capable of triggering a variety of cellular alterations that can affect gene expression and the biochemical balance of intracellular events. We have investigated the effect of TPA on such properties as rate of proliferation, differentiation, expression of cell surface molecules, and susceptibility to natural killer (NK) cell-mediated cytolysis. Four human leukemia and lymphoma cell lines; K562, MOLT 4, Raji, and HL60, were studied in their response to TPA treatment. Based on measurements of the defined cellular properties, we have characterized the pleiotropic responses of each tumour cell line to the phorbol ester in relation to intensity and time of onset of each response. The effects of TPA are highly varied, ranging in time of onset from minutes to days, and in intensity from strong to weak within the four cell lines studied. However, within all the processes that are affected, the activation of protein kinase C appears to be a common initiating event of phorbol ester induction.
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PMID:Flow cytometric analysis of the phenotypic changes in tumour cell lines following TPA induction. 340 83

Pregnancy was considered to aggravate concomitant neoplasia; however, recent observations in humans and experimental animals suggest that on the contrary tumor growth may be unfavorably affected by pregnancy. For this relationship to be investigated, a serially transplantable virus-induced lymphoma was inoculated into female rats of two different strains (WF and SD) in early or in late pregnancy. While all nonpregnant control rats died with lymphoma in 8-10 weeks, 36-75% of rats inoculated with lymphoma cells in the 1st week of pregnancy remained free of tumors, and 20-54% had tumors half the size of those in controls. When lymphoma cells were inoculated in the last week of pregnancy, the protective effect of pregnancy, although less clearly manifested, still resulted in 11% rats free of tumors and 78-91% rats with tumors markedly smaller than those of controls. Nonpregnant rats receiving pregnant rat serum in twice weekly injections grew tumors only 25-60% the size of those in rats receiving sera of nonpregnant rats. In vitro, pregnant rat sera added to the tissue culture media of rat lymphoma (AS line) or human leukemia (MOLT-4) cells resulted in reductions of viable target cells of 67-71%, respectively. The present experiments show that transplanted lymphoma cells that are 100% lethal in nonpregnant rats were totally or partially inhibited in their growth when the recipients were pregnant. Similar inhibiting effects were observed when pregnant rat serum was administered to lymphoma cells in vivo and in vitro. The protective effect against tumor growth was greater during early pregnancy, less accentuated during late pregnancy, and ceased entirely post partum and particularly during lactation, when tumor growth resumed on an accelerated course.
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PMID:Protective effect of pregnancy against transplantation of lymphoma in rats. 346 17

We studied the expression of the genes encoding the A and B chains of platelet-derived growth factor (PDGF) in a number of human leukemia cell lines. Steady-state expression of the A-chain RNA was seen only in the promonocytic leukemia cell line U937 and in the T-cell leukemia cell line MOLT-4. It has previously been reported that both PDGF A and PDGF B genes are induced during megakaryoblastic differentiation of the K562 erythroleukemia cells and transiently during monocytic differentiation of the promyelocytic leukemia cell line HL-60 and U937 cells. In this study we show that PDGF A RNA expression was induced in HL-60 and Jurkat T-cell leukemia cells and increased in U937 and MOLT-4 cells after a 1- to 2-h stimulation with an 8 pM concentration of transforming growth factor beta (TGF-beta). PDGF A RNA remained at a constant, elevated level for at least 24 h in U937 cells, but returned to undetectable levels within 12 h in HL-60 cells. No PDGF A expression was induced by TGF-beta in K562 cells or in lung carcinoma cells (A549). Interestingly, essentially no PDGF B-chain (c-sis proto-oncogene) RNA was expressed simultaneously with PDGF A. In the presence of TGF-beta and protein synthesis inhibitors, PDGF A RNA was superinduced at least 20-fold in the U937 and HL-60 cells. PDGF A expression was accompanied by secretion of immunoprecipitable PDGF to the culture medium of HL-60 and U937 cells. The phorbol ester tumor promoter tetradecanoyl phorbol acetate also increased PDGF A expression with similar kinetics, but with a mechanism distinct from that of TGF-beta. These results suggest a role for TGF-beta in the differential regulation of expression of the PDGF genes.
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PMID:Regulation of platelet-derived growth factor gene expression by transforming growth factor beta and phorbol ester in human leukemia cell lines. 347 82

The effects of combinations of dipyridamole, an effective blocker of the salvage pathway of DNA synthesis, and 8 types of anti-cancer drugs on the growth of human T, B and myeloid leukaemia/lymphoma cell lines in vitro were examined. In combinations, dipyridamole and vincristine (VCR), and dipyridamole and vindesine had synergistic inhibitory effects. Dipyridamole reduced the efflux of VCR from cells and enhanced their VCR accumulation in a dose-dependent manner at concentrations of up to 10 microM in the lymphoid cell lines, MOLT-3 and BL-TH, and of up to at least 20 microM in the myeloid cell line, ML-1. Dipyridamole also enhanced the accumulation of VCR in PHA-stimulated and un-stimulated lymphocytes of normal donors, but efflux of VCR was more rapid from normal lymphocytes than from cultured cell lines. It is proposed that combination therapy with dipyridamole plus VCR should be effective in the treatment of leukaemia and lymphoma.
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PMID:Synergistic inhibitory effects of dipyridamole and vincristine on the growth of human leukaemia and lymphoma cell lines. 347 94


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