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)

Glycosaminoglycans (GAGs) play an important role in cell-cell and cell-substratum interactions, and undergo specific changes during neutrophil development. Previous studies (Luikart, S.D., Maniglia, C. A., and Sartorelli, A. C. Cancer Res., 44: 2907-2912, 1984) have shown that both dimethyl sulfoxide and 4-beta-phorbol-12-beta-myristate-13-alpha-acetate decreased GAG production by a hypoxanthine-guanine phosphoribosyl transferase-deficient clone of HL-60 promyelocytic leukemia cells prior to the appearance of a mature myeloid or monocytoid phenotype. To expand these investigations further, GAGs were analyzed by cetylpyridinium chloride precipitation and DEAE-Sephacel ion-exchange chromatography after labeling of parental HL-60 cultures with [35S]sulfate and D-[3H]glucosamine for 6 h, following treatment with 1 microM all-trans retinoic acid (RA). Chondroitin sulfate represented the major GAG species produced, although endo-beta-galactosidase-sensitive undersulfated macromolecules which possibly might be keratan sulfate, were also identified. GAG production decreased over a time period of 144 h in culture. RA treatment reduced the amount of radiolabeled cell-associated GAGs by 50% after 48, 96, and 144 h of exposure. In contrast, commitment to myelocytic maturation of the majority (i.e., approximately 60%) of the cells occurred between 72 and 96 h of RA treatment. Concurrently with the appearance of mature granulocytic cells, two-thirds of the radiolabeled GAGs were recovered from the medium, compared to one-third in untreated cultures, a phenomenon that resulted in an overall alteration in the distribution of GAGs. When RA was removed by washing after either 48 h (i.e., precommitment to differentiation) or 96 h (i.e., postcommitment to differentiation), a 1.5- to 3.5-fold increase in GAG production was noted 48 h later; this increase was unrelated to the medium change or to alterations in cell cycle distribution. The amounts of endo-beta-galactosidase-sensitive macromolecules were unaltered. Thus, although 1 microM RA inhibited the synthesis of chondroitin sulfate by HL-60 leukemia cells, this inhibition was reversible by removal of the drug and appeared to be unrelated to the commitment to myelocytic maturation.
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PMID:Reversible effects of retinoic acid on glycosaminoglycan synthesis during differentiation of HL-60 leukemia cells. 385 15

Gangliosides were purified from the cells of two patients with hairy cell leukemia and one patient with chronic lymphocytic leukemia. Quantification of these compounds showed that these cells contain only 5-15% of the amount of lipid-bound sialic acid (gangliosides) per cell as normal lymphocytes. Structural characterization by gas-liquid chromatography, glycosidase treatment and high-performance liquid chromatography demonstrated that the major gangliosides of these leukemia cells were of the lactosyl type. Hairy cells contained monosialyllactosylceramide (II3NeuAc-LacCer), whereas chronic lymphocytic leukemia cells contained both monosialyl and disialyl lactosylceramide [II3(NeuAc)2-LacCer]. Chronic lymphocytic leukemia cell contained lesser amounts of three other gangliosides of the neolacto or lacto series as determined by endo-beta-galactosidase treatment. None of these leukemia cells contained detectable quantities of NeuAc-LcOse3Cer, a ganglioside found in normal leukocytes.
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PMID:Gangliosides of human chronic lymphocytic leukemia and hairy cells. 640 68

In order to identify the molecule components carrying polyglycosyl chains on cell surfaces a two-step enzymatic method was developed. In the first step, the cells were incubated with endo-beta-galactosidase to selectively expose terminal N-acetylglucosamine residues of the lactosamine backbone to the chains. In the second step these residues were glycosylated by incubation with galactosyltransferase and radioactive UDP-galactose. As many as 2.5-3.0 X 10(6) residues per cell could be transferred to human erythrocytes. Negligible amounts of labeling occurred if either of the enzymes was omitted from the incubations. Of the label 80% was found in glycoproteins. In accordance with previous observations, bands 3 and 4.5 were found to be the main carriers of polyglycosyl chains. In human promyelotic HL-60 leukemia cells, a major band of apparent molecular weight of 110000-140000 was labeled. In addition, bands of lower molecular weight which appear to have escaped detection by previous methods were also labeled. The novel labeling method was found to be simple to perform, uses commercially available reagents, and leads to the efficient and highly specific labeling of cell surface molecules carrying polyglycosyl chains.
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PMID:Specific cell-surface labeling of polyglycosyl chains in human erythrocytes and HL-60 cells using endo-beta-galactosidase and galactosyltransferase. 642 74

During the ontogenic change from fetal to adult human erythrocytes, as well as fetal haemoglobin being replaced by adult haemoglobin, the cell-surface antigen i is converted to I (ref. 1). Recently it has been shown that this antigenic change is the conversion of the linear repeating Gal beta 1 leads to 4GlcNac beta 1 leads to 3Gal structure to branched Gal beta 1 leads to 4GlcNac beta 1 leads to 3(Gal beta 1 leads to 4GlcNac beta 1 leads to 6)Gal structure. We have shown that cell-surface labelling followed by endo-beta-galactosidase digestion can distinguish these two forms on the cell surface, and that band 3 and band 4.5 are the major carriers for these antigens on mature erythrocytes. Human leukaemic cell line K562, originally isolated from a patient at blast crisis of chronic myelocytic leukaemia, has recently been shown to synthesize glycophorin A, and to be capable of synthesizing haemoglobin upon induction. I demonstrate here that K562 cells express the fetal type (i) antigen on distinctly different glycoproteins from those of erythrocytes, by the use of cell-surface labelling followed by endo-beta-galactosidase digestion or followed by immunoprecipitation with specific antibodies.
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PMID:K562 human leukaemic cells express fetal type (i) antigen on different glycoproteins from circulating erythrocytes. 677 Feb 73

Particulate membrane preparations from K-562 [human CML (chronic-myelogenous-leukaemia)-derived] cells catalyse the transfer of [3H]galactose from UDP-[3H]-galactose and [3H]N-acetylglucosamine from UDP-[3H]N-acetylglucosamine into an endogenous product that on digestion with Pronase yields long-chain glycopeptides (mol.wt. 7000--10 000) called 'erythroglycan'. Incorporation of either labelled sugar increased up to 60 min of incubation time. The labelled erythroglycan was isolated by chromatography on Sephadex G-50 and characterized by digestion with endo-beta-galactosidase from Escherichia freundii, followed by analysis on Bio-Gel P-2 and paper chromatography. This digestion gave the following four products: (1) a disaccharide with the sequence beta GlcNAc-beta Gal; (2) a trisaccharide with the sequence betaGal-betaGlcNAc-beta Gal; (3) a larger oligosaccharide containing galactose and N-acetylglucosamine; and (4) a putative protein-linkage region.
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PMID:Cell-free biosynthesis of erythroglycan in a microsomal fraction from K-562 cells. 679 62