Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Granulocytes from patients with chronic myelogenous leukemia (CML) are morphologically identical to their normal counterparts but show marked differences in circulation patterns and in some membrane properties. We have previously shown that there is abnormal lectin binding to CML granulocytes, and aberrant sialylation of membrane glycoproteins. To examine the changes in sialylation of CML granulocytes further, we have studied membrane preparations from CML and normal granulocytes for specific sialyltransferase activity. Because sialyltransferase enzymes are specific for the configuration of the acceptor group, enzyme activity was assayed by measuring transfer of sialic acid from CMP-14C-sialic acid to substrates of defined structure. As compared with those of normal counterparts, CML extracts catalyzed a 50% higher overall rate of sialylation of asialofetuin, a substrate possessing both N- and O-linked acceptors. Studies of enzyme specificity utilizing porcine and ovine submaxillary mucins, antifreeze glycoprotein and alpha-1 acid glycoprotein as acceptors showed that the increased sialylation by CML extracts was due primarily to substrates with the O-linked Gal beta 1----3GaINAc acceptor group. These data suggest that sialyltransferase activity is increased in CML granulocytes compared to normal granulocytes and that the increased enzyme activity is specific for O-linked Gal beta 1----3GaINAc. This enzyme activity may be directly responsible for the abnormal membrane sialylation and pathophysiological behavior of these cells.
 ...
PMID:Increased activity of a specific sialyltransferase in chronic myelogenous leukemia. 241 27

Adherence reactions involving human leukocytes are mediated by a family of glycoprotein surface antigens composed of three different alpha subunits designated alpha L, alpha M, and alpha X, each of which is associated with a single beta subunit in an alpha 1 beta 1 heterodimer structure. We cloned the cDNA for the common beta subunit and investigated beta subunit mRNA expression in HL-60 promyelocytic leukemia cells and human granulocytic cells. Leukocyte adherence receptor beta subunit mRNA transcripts were present in low levels in HL-60 myeloblasts and promyelocytes and increased 10-fold or greater with chemically induced differentiation to more mature granulocytes (using retinoic acid and dimethylformamide) or monocyte/macrophages (using phorbol myristate acetate). Levels of beta subunit mRNA expression were also increased both in normal human peripheral blood granulocytes and in granulocytes from patients with chronic myelogenous leukemia. Nuclear run-off assays indicated that the increased steady state level of the beta subunit mRNA in retinoic acid-differentiated HL-60 cells was secondary to enhanced beta subunit gene transcription. We conclude that mRNA levels for the beta subunit of the receptor on human leukocytes that mediates cellular adherence are increased in more mature granulocytic cells compared to immature myeloid precursors and that this enhanced mRNA expression is transcriptionally regulated.
 ...
PMID:Transcriptional regulation of the leukocyte adherence protein beta subunit during human myeloid cell differentiation. 290 19

Glycolipids from human leukemia cells were analyzed by gas-liquid chromatography, enzymatic hydrolysis and high-performance thin-layer chromatography with immunostaining by the use of mouse monoclonal antibody. Glucosylceramide, lactosylceramide, and ganglioside GM3 were found in various leukemia cases. Acute lymphoblastic leukemia cells contained little or none of the glycolipids with lacto-series structures such as neolactotetraosylceramide (nLc4Cer), NeuAc alpha 2-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-Cer, or NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-Cer (IV6NeuAc-nLc4Cer), which were found in every case of various myeloid leukemias. GM3 was a major ganglioside (45-100%) in acute leukemia cells, whereas IV6NeuAc-nLc4Cer was a major one (37%) in chronic myelogenous leukemia cells.
 ...
PMID:Comparison of glycolipids in various human leukemia cells. 312 59

Platelet alpha granules contain several growth factors such as the transforming growth factor beta (TGF-beta) that are released during blood clotting and are thought to participate in the repair of tissue injury; however, the site of synthesis of platelet TGF-beta has not been demonstrated. We studied TGF-beta expression during megakaryoblastic differentiation of the chronic myeloid leukemia cell line K562 in vitro. These cells have mainly erythroid characteristics but acquire several megakaryoblastic properties when treated with the phorbol diester 12-0-tetradecanoyl-13-phorbolacetate (TPA). During four subsequent days of megakaryoblastic differentiation the amount of the 2.5-kilobase (kb) TGF-beta mRNA increased about eightfold, and a novel 2.3-kb mRNA species was induced in the K562 cells. This occurred concomitantly with distinct induction patterns of platelet-derived growth factor A (PDGF-A) and c-sis (PDGF-B chain) RNAs and several platelet antigens. The expression of erythroid markers such as glycophorin A decreased. Culture media of TPA-differentiated K562 cells also contained TGF-beta polypeptides as shown by a sensitive radioreceptor assay and by immunoprecipitation after metabolic labeling of the cells. These polypeptides were not seen in culture media from dimethyl sulfoxide- or sodium butyrate-treated cells. Unlike in several other cells, exogenously added TGF-beta 1 or 2 affected neither TGF-beta nor PDGF RNA expression in K562 cells.
 ...
PMID:Enhanced expression of transforming growth factor beta during megakaryoblastic differentiation of K562 leukemia cells. 316 93

We have isolated and sequenced a cDNA clone encoding the mouse LAMP-1 (mLAMP-1) major lysosomal membrane glycoprotein. The deduced protein sequence, which included the NH2-terminal portion of the mLAMP-1 molecule, consisted of 382 amino acids (Mr 41,509). The predicted structure of this protein included an NH2-terminal intralumenal domain consisting of two homology units of approximately 160 residues each separated by a proline-rich hinge region. Each homology unit contained four cysteine residues with two intercysteine intervals of 36-38 residues and one of 68 or 76 residues. The molecule also contained 20 asparagine-linked glycosylation sites within residues 1-287, a membrane-spanning region from residues 347 to 370, and a carboxyl-terminal cytoplasmic domain of 12 residues. The biochemical properties and amino acid sequence of mLAMP-1 were highly similar to those of two other molecules that have been studied as cell surface onco-differentiation antigens: a highly sialylated polylactosaminoglycan-containing glycoprotein isolated from human chronic myelogenous leukemia cells (Viitala, J., Carlsson, S. R., Siebert, P. D., and Fukuda, M. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, in press) and the mouse gp130 (P2B) glycoprotein, in which an increase in beta 1-6 branching of asparagine-linked oligosaccharides has been correlated with metastatic potential in certain tumor cells (Dennis, J.W., Laferte, S., Waghorne, C., Breitman, M.L., and Kerbel, R.S. (1987) Science 236, 582-585).
 ...
PMID:Isolation and sequencing of a cDNA clone encoding lysosomal membrane glycoprotein mouse LAMP-1. Sequence similarity to proteins bearing onco-differentiation antigens. 337 44

A novel sialylated fucosyl glycolipid, which is present at an elevated level in chronic myelogenous leukemia cells, was isolated. The structure of this fucoganglioside was elucidated by methylation analysis, fast atom bombardment-mass spectrometry, and enzymatic degradation, followed by reaction with anti-Lex, Gal beta 1----4 (Fuc alpha 1----3) GlcNAc beta 1----, monoclonal antibody. The structure of this ganglioside was found to be: (Formula: see text). This structure is unique in that a fucose is attached to the internal N-acetylglucosamine but not to the subterminal N-acetylglucosamine. Since this glycolipid is apparently absent in normal granulocytes or acute myelogenous leukemia cells, it can be a specific marker for chronic myelogenous leukemia cells. Based on the structures of this fucoganglioside and normal granulocyte glycolipids, a biosynthetic pathway of extension, sialylation, followed by fucosylation is proposed.
 ...
PMID:Structure of a novel sialylated fucosyl lacto-N-norhexaosylceramide isolated from chronic myelogenous leukemia cells. 345 27

We have examined granulocytes from patients with chronic myelogenous leukemia (CML) and from normal subjects to determine whether activity of a specific sialyltransferase might account for the aberrant sialylation of O-linked membrane oligosaccharides in CML cells. Total membrane preparations of morphologically mature CML and normal granulocytes were tested for sialyltransferase activity using the substrates galactosyl-beta 1-3-N-acetyl-D-galactosamine-alpha-O-nitrophenyl and N-acetyl-D-galactosamine-alpha-phenyl. N-Acetyl-D-galactosamine-alpha-phenyl was not an acceptor with either CML or normal cells. With galactosyl-beta 1-3-N-acetyl-D-galactosamine-alpha-O-nitrophenyl, sialyltransferase activity was 2.8 times higher in CML cells compared to normal cells. Product identification by high performance liquid chromatography showed that enzyme from both normal and CML granulocytes linked sialic acid to galactosyl-beta 1-3-N-acetyl-D-galactosamine-R by the alpha(2-3) and not the alpha(2-6) linkage. The enzyme CMP-N-acetylneuraminic acid: galactosyl-beta 1-3-N-acetyl-D-galactosamine-R alpha(2-3)-sialyltransferase has not previously been described in human granulocytes. The marked increase in activity of this enzyme in CML and the resulting increase in sialylation may contribute to the pathophysiological behavior of CML granulocytes.
 ...
PMID:Presence of cytidine 5'-monophospho-N-acetylneuraminic acid:Gal beta 1-3GalNAc-R alpha(2-3)-sialyltransferase in normal human leukocytes and increased activity of this enzyme in granulocytes from chronic myelogenous leukemia patients. 347 17

Polylactosaminoglycans were isolated from human chronic myelogenous leukemia cells and their structures were elucidated. The lactosaminoglycan saccharides were isolated by hydrazinolysis and fractionated by QAE-Sephadex. The structures of fractionated oligosaccharides were analyzed by fast atom bombardment-mass spectrometry and methylation before and after treatment with specific exoglycosidases, such as alpha 2----3 specific neuraminidase. Based on these experiments, the structures of sialyl polylactosaminoglycans of chronic myelogenous leukemia cells were found to contain the following unique structure which is absent in normal mature granulocytes: (formula; see text) In addition to this, chronic myelogenous leukemia polylactosaminoglycans can be distinguished from normal granulocyte polylactosaminoglycans by the following characteristics. Leukemic polylactosaminoglycans are (a) shorter, (b) more highly sialylated and contain fully sialylated, tetrasialosyl polylactosaminoglycans, (c) are less fucosylated at C-3 of N-acetylglucosamine of polylactosaminyl side chains, and (d) contain a significant amount of sialyl Lex, NeuNAc alpha 2----3Gal beta 1----4(Fuc alpha 1----3)GlcNAc beta 1----3, structure. These results indicate that chronic myelogenous leukemia cells express unique polylactosaminoglycan structures which are distinct from normal mature granulocytes.
 ...
PMID:Structures of sialylated fucosyl polylactosaminoglycans isolated from chronic myelogenous leukemia cells. 386 14

Changes in glycosphingolipid (GSL) composition during differentiation of human leukemic granulocytes were investigated qualitatively and quantitatively in immature and mature granulocytic cells derived from human chronic myelogenous leukemia (CML) cases and were compared with those found in the in vitro granulocytic differentiation of the human promyelocytic leukemia HL-60 cell line. Two neutral GSLs, ceramide monohexoside and ceramide dihexoside, and two molecular species of gangliosides, one being the ganglio-series ganglioside NeuAc(alpha 2-3)Gal(beta 1-4)Glc-Cer (GM3) and the other being the lacto-series sialosylparagloboside, were predominant in the granulocytic cells at an early maturation stage. During the granulocytic differentiation of CML cells, the contents of ceramide dihexoside and paragloboside increased strikingly with a concomitant decrease in ceramide monohexoside, and the total amount of neutral GSLs increased to about three times as much as that of the most immature granulocytic cells, myeloblasts. On the other hand, lacto-series gangliosides, with longer sugar moieties increased with a concomitant decrease in ganglio-series ganglioside GM3, and the ganglioside profile became more complex. The total content of ganglioside increased in parallel with the complexity of the ganglioside profile. Similar differentiation-associated changes were also found in GSL composition during the in vitro granulocytic differentiation of HL-60 cells. However, a marked difference between the differentiation-dependent change in the GSL composition of CML cells and that of HL-60 cells was observed for a ganglioside species which was found to be one of the major gangliosides in normal neutrophils: in the former, the ganglioside level increased up to the level in normal mature granulocytes as the cells differentiated; in contrast, it decreased significantly during granulocytic differentiation of the latter cells. When the GSL composition of the neutrophils obtained from CML cells, which were apparently normal as to morphology, stimulus-induced membrane potential changes, and superoxide-producing capacity, was compared with that of normal neutrophils, an obvious difference was observed between them, especially with regard to ganglioside GM3; the amount of ganglioside GM3 in the former was about one-sixth of that in the latter. This finding indicates some alterations in the cell membrane structure of neutrophils of CML origin.
 ...
PMID:Changes in glycosphingolipid composition during differentiation of human leukemic granulocytes in chronic myelogenous leukemia compared with in vitro granulocytic differentiation of human promyelocytic leukemia cell line HL-60. 386 27

Gangliosides isolated from the cells of three patients with chronic myelogenous leukemia (CML) were purified by Folch partitioning, diethylaminoethyl Sephadex, Florisil (acetylated gangliosides), and silicic acid chromatography and were structurally analyzed using thin-layer and gas-liquid chromatography, methylation analysis, enzyme degradation, and high-performance liquid chromatography. With these methods, the major gangliosides isolated were II3-alpha-N-acetylneuraminosyl-lactosylceramide, IV3-alpha-N-acetylneuraminosyl-neolactotetraosylceramide (sialosylparagloboside), and a ganglioside with the following structure: NeuAc alpha 2 leads to 3(Gal beta 1 leads to 4 GlcNac beta 1 leads to 3)2Gal beta 1 leads to 4Glc beta 1 leads to 1Cer. This ganglioside has previously been characterized as an "i" active compound. Like normal neutrophils, CML cells contain monosialogangliosides that belong to the lactosyl and neolacto family. However, our study shows that CML cells differed from normal neutrophils in that they contained less total ganglioside, and their major ganglioside species is II3-alpha-N-acetylneuraminosyl-lactosylceramide. Differences between gangliosides of CML and acute nonlymphoblastic leukemias are discussed.
 ...
PMID:Isolation and characterization of gangliosides from chronic myelogenous leukemia cells. 658 65


<< Previous 1 2 3 4 Next >>