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)

From ten consecutive patients with acute myeloid leukemia leukemic cells were isolated and cultured with and without 10(-6), 10(-7) and 10(-8) M 1.25(OH)2D3 (vit D3), retinoic acid (RA) cytosine-arabinoside (ARA-C) and 1.0, 1.25 and 1.5% dimethyl sulfoxide (DMSO). Maturation was measured with a comprehensive panel of qualitative and quantitative parameters of maturation. Six of those ten leukemias showed significant (p less than 0.01) changes in at least three parameters after exposure to either one of the differentiation inducers. Vit D3 induced maturation in four leukemias, in three of them clearly in monocytic direction. ARA-C showed changes in one leukemia in only three parameters not pointing to either granulocytic or monocytic direction. Maturation in granulocytic direction was observed after exposure to RA in one leukemia. Maturation induction was observed in six out of ten freshly isolated leukemic cells with vit D3 being the most potent inducer of maturation in monocytic direction. The data about inducibility of maturation in freshly isolated human leukemic cells are reviewed and discussed.
 ...
PMID:Maturation induction in freshly isolated human myeloid leukemic cells, 1.25 (OH)2 vitamin D3 being the most potent inducer. 254 44

Exposure of HL-60 leukemia cells to either 12-O-tetradecanoylphorbol-13-acetate (TPA), dimethylsulfoxide (DMSO), exogenous gangliosides GM3, GM1, or bovine brain ganglioside mixture (BBG) resulted in a marked inhibition of the growth of cells. The order of the inhibitory potency was TPA greater than GM3 greater than DMSO greater than BBG greater than GM1. In contrast, sulfatides were without effect on cellular replication. Treatment of HL-60 cells with TPA or GM3 induced differentiation along the monocyte/macrophage lineage, while treatment with DMSO induced maturation along the granulocytic pathway. These effects were accompanied by more than a twofold increase in protein kinase C (PKC) activity. In contrast, treatment with GM1, BBG, or sulfatides caused only a relatively small increase in PKC activity. The activity of CMP-N-acetylneuraminic acid:lactosylceramide sialyltransferase (ST1), a key enzyme for membrane gangliosides synthesis, in HL-60 cells was also influenced by the exposure to TPA, GM3, DMSO, GM1, or sulfatides. The inducers of differentiation, TPA and DMSO, caused an increase in ST1 activity, whereas GM3, which also induced cellular differentiation, inhibited ST1 activity, perhaps through the action of end-product inhibition. The non-inducers of differentiation, GM1 and sulfatides, also increased the activity of ST1, but to a much lesser extent. The findings suggest that the direct or indirect modulation of PKC activity by some of these agents may be involved, at least in part, in the regulation of cellular growth and differentiation. Furthermore, it is conceivable that differences in PKC activity may be responsible for the changes in ST1 activity associated with cell differentiation and proliferation.
 ...
PMID:Effects of inducers of differentiation on protein kinase C and CMP-N-acetylneuraminic acid:lactosylceramide sialyltransferase activities of HL-60 leukemia cells. 271 23

Change in the level of CuZn-superoxide dismutase (SOD) mRNA was examined using a molecular probe during differentiation of human monocytic leukemia U937 cells or promyelotic leukemia HL-60 cells induced by either 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or dimethylsulfoxide (DMSO). CuZn-SOD mRNA levels were found to decrease during the course of differentiation, and this response is specific for differentiation, since the treatment of human B cell leukemia cells or normal diploid fibroblasts with TPA failed to have any effect on the level of CuZn-SOD mRNA. The activity of CuZn-SOD in U937 cells also decreased during differentiation, but following that of the CuZn-SOD mRNA level. The expression of the CuZn-SOD gene is thus concluded to diminish during the differentiation of HL-60 and U937 cells.
 ...
PMID:Decrease in CuZn-superoxide dismutase mRNA level during differentiation of human monocytic and promyelotic leukemia cells. 273 85

Treatment of HL-60 leukemia cells with the inducers of differentiation dimethyl sulfoxide (DMSO) and 6-thioguanine (TG) reduces the proliferative capacity of the cells. DMSO acted in a serum-independent manner and reversibly inhibited competence to enter S phase after 24 h of treatment. Purified human granulocyte-macrophage colony-stimulating factor (GM-CSF) but not human CSF-1, restored S phase competence and growth of DMSO-treated cells over a 7-day period. GM-CSF had no effect on the saturation density of control cells, even under conditions of reduced growth. Furthermore, GM-CSF antagonized the growth inhibitory actions of TG associated with cytodifferentiation but not those associated solely with TG cytotoxicity. The number of high affinity, cell surface GM-CSF receptors doubled after treatment of HL-60 cells with DMSO for 24 h and reached a maximum 4- to 5-fold increase within 72 h of exposure. The Kd of GM-CSF binding, 240 pM, was comparable to the concentration required to elicit a mitogenic response in DMSO-treated cells. An HL-60 variant that had been selected for resistance to TG-induced growth inhibition and differentiation (R. E. Gallagher et al., Cancer Res., 44: 2642-2653, 1984) was found to have less than 20% of the cell surface GM-CSF receptors when compared to either wild type cells, or a variant line selected for resistance to TG cytotoxicity. These studies demonstrate that HL-60 cells undergoing differentiation simultaneously lose autonomous growth properties and acquire cell surface growth factor receptors and mitogenic responsiveness.
 ...
PMID:Enhanced mitogenic responsiveness to granulocyte-macrophage colony-stimulating factor in HL-60 promyelocytic leukemia cells upon induction of differentiation. 283 46

Following induction of differentiation by incubation with 1.25% dimethylsulfoxide (DMSO), cells of the HL60 promyelocytic leukaemia cell line acquire certain characteristics of the mature polymorphonuclear leucocyte (PMN) including the ability to produce oxygen radicals and to phagocytose opsonized bacteria. However, these cells are unable to fix 125I during phagocytosis and are only able to kill phagocytosed microorganisms (C. albicans and S. aureus) to a small degree compared to mature PMN. Further, release of myeloperoxidase (MPO) from cytoplasmic granules occurs to approximately 20% of control levels after 6 days culture with DMSO, and drops to negligible levels by 7 days. These data suggest an immature or inactive MPO/peroxide/halide killing system. Insensitivity to the cyclooxygenase pathway inhibitor indomethacin suggests that there may also be a defect in this pathway.
 ...
PMID:Differentiated HL60 promyelocytic leukaemia cells have a deficient myeloperoxidase/halide killing system. 300 85

The phenomenon of leukemic cell maturation requires a measurement of myeloid maturation to understand the process and to exploit it as a means of therapy for leukemia. The HL-60 leukemic cell line was used as a model of induced leukemic cell maturation in order to develop a method of quantitating granulocytic and monocytic maturation in response to drug therapy. An automated flow cytochemistry system (Hemalog-D) was employed to measure mean cell volume, myeloperoxidase (MPO), and nonspecific esterase (NSE). For granulocytic maturation induced by vitamin A or DMSO, MPO and cell volume decreased by 50%, maintaining a constant mean cellular MPO concentration throughout maturation from promyelocyte to neutrophil-like forms. For monocytic maturation induced by low-dose ARA-c, the mean NSE increased substantially, while cell volume remained constant. Unlike MPO concentration, NSE was truly inducible and thus a useful quantitative measure of maturation caused by low-dose ARA-c. Flow cytochemistry and cytofluorometry may be developed to allow for quantitative monitoring of therapeutic trials of induced maturation in human leukemias. However, this will require adapting these techniques to the complexity of human leukemias in vivo, and the necessity of handling heterogeneous populations encountered in bone marrow samples.
 ...
PMID:Measurement of myeloid maturation by flow cytochemistry in HL-60 leukemia: esterase is inducible, myeloperoxidase is not. 301 71

The proto-oncogene c-src, the cellular homolog of the Rous sarcoma virus (RSV) transforming gene v-src, is expressed in a tissue-specific and age-dependent manner. Its physiological function, although still unknown, appears to be more closely related to differentiation processes than to proliferation processes. To obtain more information about the physiological role of the c-src gene in cells, we have studied differentiation-dependent alterations using the human HL-60 leukaemia cell line as a model system. Induction of monocytic and granulocytic differentiation of HL-60 cells by 12-O-tetradecanoylphorbol-13-acetate (TPA) and dimethylsulfoxide (DMSO) is associated with an activation of the pp60c-src tyrosine kinase, but not with increased c-src gene expression. Control experiments exclude an interaction of TPA and DMSO themselves with the pp60c-src kinase.
 ...
PMID:Activation of the pp60c-src kinase during differentiation of monomyelocytic cells in vitro. 301 21

Recently, we have shown that thrombin is a chemotaxin and growth-promoting agent for cells of the mononuclear phagocytic lineage. These activities are independent of thrombin's enzymatic activity. Unlike other chemotactic factors, thrombin is specific for monocytes and does not attract granulocytes. To further explore the cellular specificity we have used a human leukemia cell line HL-60 that is capable of in vitro differentiation toward either monocytes (HL-60/mono) following incubation with 1,25(OH)2D3, or granulocytes (HL-60/gran) following incubation with DMSO. In contrast to undifferentiated HL-60 cells or HL-60/gran, we find that HL-60/mono respond chemotactically to intact human alpha-thrombin, esterolytically inactive iPR2P-alpha-thrombin, and the thrombin-derived peptide CB67-129, previously shown to contain the thrombin chemotactic exosite. In addition, thrombin induces in HL-60/mono association of actin with the cytoskeleton and causes an increase in levels of free cytosolic Ca2+. These phenomena are well characterized as early events occurring concomitant with directed cell movement associated with exposure to chemotactic agents such as FMLP. Furthermore, in contrast to fibroblasts, both iPR2P-alpha-thrombin and the thrombin chemotactic peptide CB67-129 evoke dose-dependent [3H]TdR incorporation, protein synthesis, and cell replication in growth-arrested J-744 cells, a murine macrophage-like cell line. Limited tryptic digests of CB67-129 lose chemotactic activity but retain full mitogenic activity, demonstrating that as with PDGF, the sites on CB67-129 required for chemotaxis and mitogenesis are clearly dissociable. The mitogenic effects of the CB67-129 digest can be mimicked by a synthetic tetradecapeptide analogue of CB67-129 (residues 367-380) that includes the loop B insertion sequence, previously shown to be critical for thrombin's chemotactic effects. From these data, it is apparent that the loop B insertion is critical for thrombin's nonenzymic biological effects on cells, but additional sites are required for stimulation of cell movement.
 ...
PMID:Hormone-like activity of human thrombin. 303 49

A 93-kDa tyrosine protein kinase (p93) identified previously as the gene product of the c-fes proto-oncogene, is highly expressed in HL-60 leukemia cells induced to differentiate to the granulocyte or monocyte phenotype. We have now studied the relationship of p93 to the differentiation process by using a dimethyl sulfoxide (DMSO)-resistant subline of HL-60 cells (HL-60/DMSO) or the parental cell line treated with peptide or protein substrates of p93. Treatment of HL-60/DMSO cells with DMSO induced neither differentiation nor the expression of p93; however, cotreatment with IFN-alpha and DMSO resulted in partial differentiation and the concomitant induction of p93 activity. Treatment of wild-type HL-60 cells by the coaddition of the p93 substrates poly(Glu,Tyr)1:1, poly(Glu,Tyr)4:1, poly(Glu,Ala,Tyr)6:3:1, angiotensin II or vasoactive intestinal peptide with DMSO or IFN-tau partially blocked differentiation and concurrently diminished the induction of p93 activity. The inhibitory concentrations of the p93 substrates were related to their Km values. These results indicate that there is an obligatory association between the expression of p93 and granulocyte/monocyte differentiation in this cell line.
 ...
PMID:Association of p93c-fes tyrosine protein kinase with granulocytic/monocytic differentiation and resistance to differentiating agents in HL-60 leukemia cells. 316 57

The human leukemic cell line HL-60 undergoes differentiation to granulocytic-like cells in response to dimethyl sulfoxide (DMSO) or retinoic acid (RA). This differentiation is accompanied by an arrest in cell proliferation. Studies have implicated alterations in the phospholipid fatty acid (FA) composition as a result of HL-60 differentiation. However, changes in FA's are also known to occur during the arrest of cellular proliferation. Using a highly efficient capillary gas-liquid chromatography technique, the phospholipid FA composition of HL-60 and of DMSO-resistant and RA-resistant HL-60 subclones was determined in proliferating cells, in density-arrested cells, and in terminally differentiated cells. The same specific modifications in some of the FAs of the three cell lines were observed when proliferation was inhibited by cell density; 16:0 and 18:2n-6 were decreased and 22:6n-3 increased. Moreover, 16 and 18 dimetylacetals were both increased when proliferation was decreased, indicating modifications in plasmalogen contents. Granulocytic differentiation of HL-60 cells and of its subclones with DMSO and/or RA provoked modifications in phospholipid FAs different from that found in density-arrested, undifferentiated cells such as decreases in monoenoic FAs of 16 and 18 carbons as well as an increase in arachidonic acid, the major polyunsaturated FA. The biological significance of these changes upon arrest of proliferation and differentiation are discussed. These results indicate that, when arrest of proliferation accompanies differentiation, these two phenomena can be responsible for different changes and, whenever possible, they have to be considered separately in order to know which modifications are effectively due to differentiation itself.
Leukemia 1988 Jul
PMID:Fatty acid composition of HL-60 cells is modified upon proliferation arrest and differentiation. 316 1


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>