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

Pharmacologic differentiation of the promyelocytic leukemia HL60 is associated with an increase in cellular tyrosine phosphatase activity. We asked (a) if this increase might, at least in part, be due to changes in a transmembranous protein-tyrosine phosphatase, CD45; and (b) if CD45 changes similarly in other differentiating leukemias. Differentiation of HL60, several chronic myelogenous leukemias, a monocytic leukemia (THP-1), and a monoblastoid leukemia (U-937) could be induced by phorbol ester, 1,25-dihydroxy vitamin D3, dimethyl sulfoxide, or cyclic AMP analogues. This differentiation was associated with a marked increase in (a) total cellular tyrosine phosphatase activity (2-4-fold as measured by the ability to dephosphorylate a tyrosine-phosphorylated peptide); (b) CD45-specific tyrosine phosphatase activity (2-4-fold); (c) CD45 cell surface expression by flow cytometry (2-5-fold); (d) synthesis of both exon B-dependent M(r) 205,000 and exon ABC- M(r) 185,000 CD45 proteins, as revealed by immunoprecipitation with antisera specific for CD45 isoforms. Both isoforms have enhanced electrophoretic mobility when isolated from the differentiated cells. This enhanced mobility did not appear to be due to decreased stoichiometry of CD45 phosphorylation on serine/threonine residues. Interestingly, 12-O-tetradecanoylphorbol-13-acetate transiently reduced CD45 protein-tyrosine phosphatase activity in the chronic myelogenous leukemia cell RWLeu4 without altering the CD45 amount (as measured by cell surface immunofluorescence). Modulation of CD45 tyrosine phosphatase activity (and protein levels) may play a role in differentiation or in maintaining cells in a nonproliferative state or may represent a phenotypic marker of differentiation.
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PMID:Differentiation-induced changes in protein-tyrosine phosphatase activity and commensurate expression of CD45 in human leukemia cell lines. 153 52

Two types of HL-60 cells, 1,25-(OH)2D3-responsive ATCC HL-60 cells and 1,25-(OH)2D3-resistant LG HL-60 cells were used. Despite the presence of enough amounts of normal 1,25-(OH)2D3 receptors, only 22% of LG cells matured after a 4-day treatment with 10(-7) M 1,25-(OH)2D3, while 80% of ATCC cells differentiated. However, 1,25-(OH)2D3 inhibited the proliferation of LG cells to the same degree as that of ATCC cells. 1,25-(OH)2D3 also induced (1) the ability to metabolize 1,25-(OH)2D3 to 1,24,25-(OH)3D3, and (2) up-regulation of the 1,25-(OH)2D3 receptor in LG as well as ATCC cells. Furthermore, the proportion of mature LG cells was 78% after treatment with 10(-7) M 1,25-(OH)2D3 for the first 48 h and 10(-7) M dbcAMP for the second 48 h, which was greater than that when treated only with 10(-7) M dbcAMP for the second 48 h (24.2%). These results indicate that 1,25-(OH)2D3 receptor complexes function normally in LG cells at commitment step in cell differentiation. ATCC cells had a serine proteinase to destroy specific 1,25-(OH)2D3-binding activity of the unoccupied receptor and digest 53-kD receptor to a small fragment with a MW of 16.3 kD, while not affecting the level of the specific binding of the occupied receptor. Other cells, such as murine leukemia cells, M1, and human chronic myeloid leukemia cells, the differentiation of which is induced by 1,25-(OH)2D3, seemed to have the same type of proteinase, suggesting the physiological significance of this proteinase in 1,25-(OH)2D3-induced cell differentiation.
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PMID:Significance of proteolytic activity in 1,25-(OH)2D3-induced differentiation of HL-60 cells. 166 29

In addition to the 85-95 kD CD44 species found on most hemopoietic cell types, the human myelomonocytic cell line KG1a expresses proteins of approximately 115 kD and 130 kD that react with monoclonal antibodies belonging to CD44. The possibility that these higher molecular weight species may represent novel CD44 isoforms containing additional protein sequence was investigated. CD44 cDNA clones were isolated from a plasmid-based expression library prepared from KG1a mRNA. One of the three clones obtained (clone 2.3) was found to encode a CD44 molecule of approximately 130 kD in transfected COS cells. Sequences analysis indicated that the molecule encoded by this cDNA clone, designated CD44R1, was essentially identical to CD44 except for the presence of an additional 132 amino acids inserted into the extracellular domain. This inserted region is rich in serine and threonine residues that may serve as sites of O-linked glycosylation, and contains a potential site of N-linked glycosylation and a potential site of chondroitin sulphate attachment. PCR analysis using primers that flank the inserted region present within CD44R1 identified an additional CD44 isoform, designated CD44R2, that contains only the last 69 amino acids present within the unique region of CD44R1. Peripheral blood mononuclear cells and granulocytes from normal individuals and patients with chronic myelogenous leukemia, polycythemia vera, or acute myelomonocytic leukemia, express both CD44R1 and CD44R2. In contrast, CD44R1 and CD44R2 appear to be differentially expressed in various CD44-positive cell lines. Thus KG1a, and the Epstein-Barr Virus-transformed B cell lines WalkDR4 and Way-1 express both CD44 and the CD44 isoforms CD44R1 and CD44R2, while the myeloid cell lines HL60 and U937 express high levels of CD44, but only very low levels of CD44R1 and CD44R2. The CD44-negative cell lines DHL-4, DHL-10, Jurkat, and K562 are also negative for CD44R1 and CD44R2.
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PMID:Molecular cloning of CD44R1 and CD44R2, two novel isoforms of the human CD44 lymphocyte "homing" receptor expressed by hemopoietic cells. 205 74

An altered c-abl gene product (P210bcr-abl) possessing associated tyrosine protein kinase activity was recently been reported in several blast chronic myelogenous leukemia (CML) cell lines. We have examined different morphological types of leukocytes directly obtained from patients at the blast crisis stage of CML for expression of P210bcr-abl tyrosine protein kinase activity. Phosphorylation of P210bcr-abl in an immune complex kinase assay using an anti-v-abl peptide serum was observed in blast cells from four Philadelphia chromosome (Ph1)-positive CML patients in blast crisis. P210bcr-abl protein kinase activity was detected regardless of whether the blast cells were of myeloid, lymphoid, or undifferentiated morphology. P210bcr-abl protein kinase activity was not detected in immune complexes either from leukocytes of four Ph1-negative CML patients in blast crisis, of five acute myelogenous leukemia patients, or in the promyelocytic cell line HL-60. Mature myeloid cells are associated with an inhibitory factor for not only P210bcr-abl protein kinase activity, but also protein kinases in general. Therefore, analyses of Ph1-positive benign phase CML myeloid cells, the majority of which are well differentiated, could not be successfully performed. The inhibition of P210bcr-abl protein kinase activity is not a specific property of mature cells from CML patients since granulocytes from a normal volunteer also demonstrated a similar effect. However, extracts of Ph1-positive cultured B-lymphocytes from a patient in benign phase demonstrated active P210bcr-abl protein indicating that the P210bcr-abl protein is expressed in an enzymatically active form in the earlier phases of CML. In addition to the previously reported P210 and P190 abl-related proteins, a novel Mr 53,000 protein was found to undergo phosphorylation at serine and tyrosine in immune complex kinase assays of two blast crisis CML cell lines (K562 and EM2) and in samples from blast crisis patients in which P210bcr-abl was detected. Peptide mapping by the Cleveland technique suggested that Mr 53,000 protein is unrelated to P210bcr-abl. Immune complex kinase assays of K562 cells with an anti-src serum (GD-11) yielded active c-src kinase and a Mr 50,000 phosphorylated protein, both of which were resistant to alkaline hydrolysis. Peptide mapping suggested that Mr 53,000 protein is related to Mr 50,000 protein which is precipitated with P210bcr-abl as an Mr 300,000 protein complex.
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PMID:Analysis of P210bcr-abl tyrosine protein kinase activity in various subtypes of Philadelphia chromosome-positive cells from chronic myelogenous leukemia patients. 243 23

Human chronic myelogenous leukemia is characterized by a reciprocal translocation between chromosomes 9 and 22. This results in the transfer of the c-abl protooncogene from chromosome 9 into the bcr gene on chromosome 22. The purpose of this study was to characterize the bcr and related gene products. Antibodies were raised against a fused trpE-bcr protein induced in a bacterial expression vector. Immunoprecipitation with the monoclonal and polyclonal antibodies of metabolically [35S]methionine labeled leukemic cell lines shows a 210, 160 and 130 Kda protein in Philadelphia positive cells containing the bcr-abl fused transcript. Only the 160 and 130 Kda were present in the Philadelphia negative cells. In vitro kinase assay shows that the 130 Kda protein is a phosphoprotein mainly phosphorylated on serine. Partial proteolysis indicates that the p210 and p130 share common domains. In subcellular fractionation experiments, the p130 is colocalized with the p210 bcr-abl in the cytoplasmic fraction. Together with the mapping of 4 distinct bcr related loci our data suggest that the 130 Kda phosphoprotein belongs to a wider family of bcr related gene products.
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PMID:Identification of a 130 Kda bcr related gene product. 249 32

Three antisera against the mouse v-abl gene product were used to identify two potential human c-abl gene products in the chronic myelogenous leukemia cell line K562. Two antipeptide sera were generated in rabbits using the predicted amino acid sequence of the mouse v-abl gene product. One antiserum was made against a polypeptide overlapping the in vivo tyrosine phosphorylation site of murine P120gag-abl and what is believed to be a homologous tyrosine phosphorylation site of the predicted normal human c-abl gene product (v-abl 263-280). The second antipeptide serum, abl 389-403, was generated against a predicted hydrophilic peptide of the v-abl gene product. Immunoprecipitation from K562 cells metabolically labeled with [32P]orthophosphate by a mouse tumor regressor and abl 389-403 antipeptide sera detected two proteins of 190,000 and 240,000 Da. Both proteins were labeled primarily at serine and, to a much lesser extent, at tyrosine residues. Immune complex kinase assays using conditions that allow the tyrosine phosphorylation of P120gag-abl showed that in vitro phosphorylation of P190 and P240 occurs primarily at tyrosine residues. The detection of these enzymatically active human c-abl gene products is a rare observation which may be in part attributed to the c-abl gene translocation from chromosomes 9 to 22 occurring in the vast majority of chronic myelogenous leukemia patients.
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PMID:The human cellular abl gene product in the chronic myelogenous leukemia cell line K562 has an associated tyrosine protein kinase activity. 298 32

The hallmark of human chronic myeloid leukaemia is a 9;22 chromosome translocation that fuses most of the c-abl oncogene to the 5' portion of the breakpoint cluster region (bcr) gene, such that a hybrid bcr-abl mRNA and polypeptide are generated. To clarify further the nature of this translocation, we have analysed the structure of normal human bcr mRNA by isolating large cDNA clones that collectively span the entire coding region and extend 2.6 kb upstream of those previously described. The 3150-bp nucleotide sequence reported here includes 534 bp of a GC-rich 5' non-coding segment and indicates, in conjunction with published sequences, that the bcr polypeptide comprises 1271 amino acid residues. The predicted polypeptide is unrelated to serine or tyrosine kinases, or indeed to any previously published sequence; its structure provides no evidence of a transmembrane region. Since probes from throughout the 4.8-kb cloned region hybridized to both the 4.5 and 6.7 kb normal bcr transcripts, both RNAs contain most or all of that region.
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PMID:cDNA sequence for human bcr, the gene that translocates to the abl oncogene in chronic myeloid leukaemia. 310 80

In chronic myelocytic leukemia, the human c-abl oncogene is translocated from chromosome 9 to a region on chromosome 22 designated as the breakpoint cluster region (bcr) (A. de Klein, A. Guerts van Kessel, G. Grosveld, C. R. Bartram, A. Hagemeyer, D. Bootsma, N. K. Spurr, N. Heisterkamp, J. Groffen, and J. R. Stephenson, Nature (London) 300:765-767, 1982; J. Groffen, J. R. Stephenson, N. Heisterkamp, A. de Klein, C. R. Bartram, and G. Grosveld, Cell 36:93-99.) Abnormal c-abl homologous mRNA and protein have been detected in the leukemic cells of patients with chronic myelocytic leukemia (E. Canaani, D. Stein-Saltz, E. Aghai, R. P. Gale, A. Berrebi, and E. Januszewicz, Lancet 1:593-595, 1984; S. J. Collins and M. T. Groudine, Proc. Natl. Acad. Sci. USA 80:4813-4817, 1983; R. P. Gale and E. Canaani, Proc. Natl. Acad. Sci. USA 81:5648-5652, 1984; J. B. Konopka, S. M. Watanabe, J. W. Singer, S. J. Collins, and O. N. Witte, Proc. Natl. Acad. Sci. USA 82:1810-1814, 1985). The abnormal mRNA represents a chimeric transcript consisting of 5' bcr and 3' c-abl sequences (G. Grosveld, J. Verwoerd, T. van Agthoven, A. de Klein, K. L. Ramachandran, N. Heisterkamp, K. Stam, and J. Groffen, Mol. Cell. Biol. 6:607-616, 1986; E. Shtivelman, B. Lifshitz, R. B. Gale, and E. Canaani, Nature (London) 315:550-554, 1985; K. Stam, N. Heisterkamp, G. Grosveld, A. de Klein, R. S. Verma, M. Coleman, H. Dosik, and J. Groffen, N. Engl. J. Med. 313:1429-1433, 1985). In the present study, we demonstrated that the abnormal c-abl protein is a fusion protein. In addition, the normal gene encompassing bcr sequences was shown to encode a 160,000-dalton phosphoprotein with an associated serine or threonine kinase activity. We propose that this gene be designated phl, reserving the term bcr for the region within the phl gene encompassing the Ph' translocation breakpoints.
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PMID:Evidence that the phl gene encodes a 160,000-dalton phosphoprotein with associated kinase activity. 329 55

The Philadelphia chromosome found in essentially all patients with chronic myelogenous leukemia is now known to express a chimeric mRNA of 8.5 kb derived from sequences on chromosome 22 and sequences on chromosome 9. The chromosome 9 component of the chimeric RNA is derived from a subset of the exons of the abl oncogene. A portion of the exonic sequences of a gene referred to as bcr on chromosome 22 make up the amino-terminal portion of this chimeric mRNA and gene product. Our laboratory has recently succeeded in obtaining full-length clones of the 8.5 kb mRNA. The sequence analysis of this large mRNA reveals an exceptionally G-C rich 5' untranslated region. A complete open reading frame initiating in sequences of the bcr gene and reading through the abl oncogene segment has been determined. The sequence also reveals an extremely high percentage of serine residues in the bcr segment of the chimeric protein.
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PMID:Involvement of the abl oncogene in human chronic myelogenous leukemia. 333 6

An acidic variant form of arylsulfatase B from normal leukocytes and chronic myelogenous leukemia (CML) leukocytes was found to be phosphorylated at its serine and threonine residues through in vivo phosphorylation with 32Pi. However, the predominant phosphorylation site was serine in normal cells, in contrast to threonine in CML cells. A cyclic AMP-dependent protein kinase was responsible for phosphorylation of the sulfatase of CML cells.
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PMID:Protein phosphorylation of lysosomal arylsulfatase B in normal and leukemic leukocytes. 346 94


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