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)

Human granulocyte colony-stimulating factor (G-CSF) rapidly loses the biological activity and the receptor binding capacity following radioiodination. We have made a mutein of human G-CSF, KW-2228, in which Thr-1, Leu-3, Gly-4, Pro-5, and Cys-17 were respectively substituted with Ala, Thr, Tyr, Arg, and Ser; showed more potent G-CSF activity; and retained full biological activity and receptor binding capacity at least 2 weeks of radioiodination. G-CSF is an effective growth factor for the blasts of myeloid leukemia. Radioiodinated KW-2228 was prepared using solid-phase glucose oxidase-lactoperoxidase. Human leukemia cell lines and the blast cells from leukemia patients were examined for binding. High affinity binding sites were identified on myeloid cell lines and on the blasts obtained from acute myeloid leukemia patients. Scatchard analysis showed that a single binding site for G-CSF was observed (361-1688 receptors/cell; Kd 128-1400 pM). In contrast, specific binding of 125I-KW-2228 was not demonstrated on lymphoblastic cell lines or the blast cells of acute lymphoid leukemia or lymphoma. This difference was reflected in the effectiveness of G-CSF to stimulate colony formation in acute myeloid leukemia blasts, while G-CSF did not stimulate colony formation of the blast cells from acute lymphoid leukemia.
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PMID:Receptor binding of human granulocyte colony-stimulating factor to the blast cells of myeloid leukemia. 168 9

Blast cells from 26 cases of acute myeloid leukaemia (AML) were examined, by single and "two-colour" flow cytometry, for relationships between membrane CD11b (monoclonal antibody OKM1), CD11c (KB90) and CD14 (Leu-M3). Increased expression of all three determinants was associated with myelomonocytic leukaemias, with their relative diagnostic value in discriminating monocytic (M4 and M5) from non-monocytic (M1, M2 and M3) subtypes being CD14 greater than CD11c greater than CD11b. However, the results also indicated, because of the heterogenous expression of CD11c in particular, and to a lesser extent CD11b, that the patterns or histograms of fluorescent staining were potentially more informative than an empirical subdivision of blasts into positive and negative subpopulations. In addition, analysis of phenotypic correlations by simultaneous two-colour fluorescence showed that the expression of CD11b and CD11c determinants by leukaemic myeloid blasts was highly correlated, in contrast to the expression of CD14 and CD11c which were relatively independent. Consequently, CD11c+ myeloid blasts almost always coexpressed CD11b whereas CD14+ cases of AML often comprised CD14+ CD11c+ and CD14+ CD11c- subpopulations. It is concluded from these observations that CD11c immunophenotyping is a useful supplementary investigation, particularly in CD14- cases of myelomonocytic leukaemia. However, it is also apparent that the presence of membrane CD11c per se is not lineage-specific and that the level of expression is perhaps a more discriminatory factor.
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PMID:Flow cytometric analysis of membrane CD11b, CD11c and CD14 expression in acute myeloid leukaemia: relationships with monocytic subtypes and the concept of relative antigen expression. 168 68

Lys103 and Lys421 of Moloney murine leukemia virus reverse transcriptase have been implicated in the dNTP binding function as judged by their reactivity to a substrate binding site-directed reagent, pyridoxal 5'-phosphate (Basu, A., Nanduri, V. B., Gerard, G. F., and Modak, M. J. (1988) J. Biol. Chem. 263, 1648-1653). To assess the true catalytic importance of the individual lysine residues in Moloney murine leukemia virus reverse transcriptase, we mutated Lys103 and Lys421 to leucine and alanine, respectively. Analysis of the mutant enzymes revealed that mutation at the 103 position had a drastic effect on the DNA polymerase activity whereas the 421 mutation had no effect. Both mutants exhibited normal RNase H activity as well as the ability to bind to RNA or DNA templates as judged by UV-mediated cross-linking of the enzyme to the template primers. The enzyme with mutation at codon 421 (Lys----Ala) exhibited properties that were indistinguishable from the wild type with respect to its mode of catalysis, i.e. preference of template primer and divalent metal ion, RNA- or DNA-dependent DNA polymerase activity, RNase H activity, and the processive mode of DNA synthesis. These observations suggest that only Lys103 and not Lys421 is the catalytically important residue that is involved in the binding of substrate dNTP in Moloney murine leukemia virus reverse transcriptase.
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PMID:Site-directed mutagenesis of Moloney murine leukemia virus reverse transcriptase. Demonstration of lysine 103 in the nucleotide binding site. 169 72

Using a monoclonal antibody specific to the Lewis X antigen (anti-Lex), the authors studied 103 cases of Hodgkin's disease (HD) in comparison with 57 cases of non-Hodgkin's lymphoma (NHL); three cases of granulocytic sarcoma (GS); two cases of malignant histiocytosis (MH); one case of monoblastic leukemia (ML); one case of interdigitating reticulum cell sarcoma (IRCS); six cases of histiocytosis X (HX); one case of reticulohistiocytoma (RH); 44 various reactive conditions of the lymph node (LN). Reed-Sternberg and related (R-S) cells stained selectively in 80 of 92 cases of HD (87.0%), excluding 11 cases of lymphocyte predominance type. The stain was better in B-5-fixed specimens than in formalin-fixed specimens, showing a dense deposit of reaction products at a paranuclear site and on the cell surface. The staining results were compared with those of Leu-M1 and found to be superior both qualitatively and quantitatively (detection rate of R-S cells: 87.0% versus 68.5% of Leu-M1). Granulocytes, rare epithelioid histiocytes, and some endothelial and/or erythrocytes also stained with anti-Lex. The stain had positive results in three cases of GS showing a diffuse cytoplasmic staining pattern. Of NHL, two of 29 peripheral T-cell lymphomas stained to show rare paranuclear deposits without cell surface staining. The stain had negative results in MH, ML, IRCS, HX, and RH. Of 45 reactive LN, minute subcapsular collections of Lewis X+, altered-appearing Langerhans'-like cells, were observed in all ten LN from human immunodeficiency virus (HIV)-associated persistent generalized lymphadenopathy (PGL). The stain had negative results in all other various reactive conditions of LN. In conclusion, Lewis X staining is useful as a marker for R-S cells in paraffin sections with staining results superior to those of Leu-M1. Lewis X staining also detects subcapsular clustering of altered-appearing Langerhans'-like cells in PGL, which has not been described previously and warrants additional study.
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PMID:The Lewis X antigen. A new paraffin section marker for Reed-Sternberg cells. 170 18

We have labeled the primer binding domain of murine leukemia virus reverse transcriptase (MuLV RT) by covalently cross-linking 5' end labeled d(T)8 to MuLV RT, using ultraviolet light energy. The specificity and the functional significance of the primer cross-linking reaction were demonstrated by the fact that (i) other oligomeric primers, tRNAs, and also template-primers readily compete with radiolabeled d(T)8 for the cross-linking reaction, (ii) under similar conditions, the competing primers and template-primer also inhibit the DNA polymerase activity of MuLV RT to a similar extent, (iii) substrate deoxynucleotides have no effect, and (iv) the reaction is sensitive to high ionic strength. In order to identify the primer binding domains/sites in MuLV RT; tryptic digests prepared from the covalently cross-linked MuLV RT and [32P]d(T)8 complexes were resolved on C-18 columns by reverse-phase HPLC. Three distinct radiolabeled peptides were found to contain the majority of the bound primer. Of these, peptide I contained approximately 65% radioactivity, while the remainder was associated with peptides II and III. Amino acid composition and sequence analyses of the individual peptides revealed that peptide I spans amino acid residues 72-80 in the primary amino acid sequence of MuLV RT and is located in the polymerase domain. The primer cross-linking site appears to be at or near Pro-76. Peptides II and III span amino acid residues 602-609 and 615-622, respectively, and are located in the RNase H domain. The probable cross-linking sites in peptides II and III are suggested to be at or near Leu-604 and Leu-618, respectively.
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PMID:Photoaffinity labeling of the primer binding domain in murine leukemia virus reverse transcriptase. 171 70

Recent immunopathologic studies have demonstrated that primary follicles and the mantle zones of secondary follicles are composed largely of virgin B lymphocytes which migrate from the bone marrow to these areas, and are the precursor cells of germinal centers. Non-Hodgkin's lymphomas corresponding to these immature B cells include mantle zone lymphoma (MZL), a primary follicle variant of MZL without reactive germinal centers, and diffuse intermediate lymphocytic (centrocytic) lymphoma. Diffuse intermediate lymphocytic lymphoma (DILL) is considered a late stage in the progression of MZL. Cytologically, these lymphomas usually resemble their normal cellular counterparts and consist predominantly of atypical small lymphoid cells with slightly-irregular and indented nuclei, moderately-coarse chromatin, inconspicuous nucleoli, and scant cytoplasm. Small lymphocytic, cerebriform and blastic variants have also been described. In smears and touch preparations, the neoplastic cells are usually prolymphocytes. Immunologically, the cells have features of virgin B cells, bearing pan-B cell antigens along with monoclonal surface IgM, with or without surface IgD, and CD5 (Leu 1) antigen, and lacking common acute lymphocytic leukemia associated (CALLA) antigen. Cytogenetically, the t(11;14)(q13;q32) has been associated with this group of lymphomas, and expression of the putative cellular oncogene bcl-1 (11q13) has been demonstrated in 30-50% of cases. Clinically, the patients have a median age of 60 years and usually present with advanced stage disease. Splenomegaly, often massive, is present in 80% of those with MZL. Patients with MZL have a significantly longer median survival (74-77 months) than those with DILL (30-33 months), and survival in both groups is significantly prolonged if a complete clinical remission is attained. Based on clinical studies, MZL should be considered a low grade lymphoma and DILL should be considered an intermediate grade lymphoma by Working Formulation criteria. The lymphomas of primary follicle/mantle zone origin are a distinct clinicopathologic entity biologically analogous to the follicular and diffuse lymphomas of germinal center origin, from which they should be distinguished in current and future classifications of non-Hodgkin's lymphoma.
Leukemia 1991
PMID:Non-Hodgkin's lymphomas of primary follicle/mantle zone origin. 171 36

Recently we reported the expression of the human natural killer cell associated antigen CD56 (Leu 19/NKH1) in plasma cells of a majority of multiple myeloma (MM) patients. CD56 is known to be an isoform of the human neural adhesion molecule N-CAM which is involved in homotypic adhesive interactions. By immunophenotyping using four CD56 specific monoclonal antibodies and immunoprecipitation analysis we here confirm that the Leu 19 antigen expressed by myeloma plasma cells is identical to N-CAM and corresponds to the 145 kDa isoform. Because of the possible biological role of adhesion molecules on myeloma cells, we compared the expression of N-CAM with the intercellular adhesion molecule 1 (ICAM-1) and the beta 1 and beta 2 integrins. By immunogold-silver staining of cytospin preparations of mononuclear cell suspensions, bone marrow plasma cells of 17 MM patients were analysed. Plasma cells expressed N-CAM (CD56) in 14 patients. ICAM-1 (CD54) in 16 patients, and beta 2 integrins (CD18) in eight patients. beta 1 integrins (CD29) were expressed in all patients. The expression of beta 2 integrins was always very weak while N-CAM, ICAM-1 and the beta 1 integrins showed a moderate to strong positivity. The plasma cells of five haematological normal individuals lacked significant N-CAM expression but were positive for ICAM-1 and both integrin subgroups. One plasma cell leukaemia patient and two out of four end-stage MM patients showed no expression of N-CAM or beta 2 integrins on their circulating plasma cells. Among 11 previously established myeloma cell lines, surface expression of ICAM-1 and the integrins was detected in most cases, while N-CAM was present in only four lines. Most cell lines showed coexpression of the fibronectin receptors (VLA-4 and VLA-5) and the laminin receptor (VLA-6). The collagen receptor (VLA-2) was not expressed. The N-CAM negative cell lines included four cell lines that were derived from plasma cell leukaemia patients. These results indicate that the expression of adhesion molecules is an intrinsic part of the biology of multiple myeloma.
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PMID:Expression of cytoadhesion molecules (CD56, CD54, CD18 and CD29) by myeloma plasma cells. 172 26

We investigated the expression of CD56 (a neural cell adhesion molecule, NCAM) and CD57 in various hematopoietic and non-hematopoietic malignant cells, using Leu-19 and Leu-7 monoclonal antibodies. Although both molecules are commonly defined as a natural killer cell marker, we found that CD56 was highly expressed on blasts from patients with acute monocytic (4/6) and megakaryocytic (3/3) leukemias. In the latter, FACS two-color analysis revealed that leukemic megakaryoblasts simultaneously expressed CD56 and platelet-related antigens. Among leukemic cell lines, one myelocytic, three monocytic, and two megakaryocytic lines were positive for CD56. On the other hand, except for one large granular lymphocytic leukemia and one multiple myeloma cell line, none of the lymphoid leukemia cell lines or lymphoblasts from patients with acute lymphocytic leukemia (ALL) (0/15), non-Hodgkin's lymphoma (NHL) (0/2), and central nervous system (CNS) leukemia (0/2) reacted with Leu-19 antibody for CD56. The expression of CD56 in leukemia cells was not significantly affected by 12-O-tetradecanoylphorbol-13-acetate (TPA). By contrast, all hematopoietic materials were negative for CD57, while non-hematopoietic neuroblastoma cell lines expressed this molecule (4/5) as well as CD56 (5/5). Cytogenetically, the NCAM gene is located at chromosome 11q23, and chromosome breaks were often observed at this location in various leukemias. Blasts from all five acute non-lymphocytic leukemia (ANLL) patients and cell lines with 11q23-proximal chromosomal breaks were positive, while those from one ALL patient with an 11q23 abnormality were negative for CD56, necessitating further studies to clarify the link between the 11q23 abnormality and CD56 expression.
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PMID:Expression of CD56/NCAM on hematopoietic malignant cells. A useful marker for acute monocytic and megakaryocytic leukemias. 172 53

The p53 gene was examined in primary lymphoblasts of 25 pediatric patients with acute lymphoblastic leukemia by the RNase protection assay and by single strand conformation polymorphism analysis in 23 of 25 cases. p53 mutations were found to occur, but at a low frequency (4 of 25). While all four mutations were identified by single strand conformation polymorphism, the comparative sensitivity of RNase protection was 50% (2 of 4). Heterozygosity was retained at mutated codons in 3 of 4 cases. One pedigree was consistent with the Li-Fraumeni syndrome, and bone marrow from both diagnosis and remission indicated a germline G to T transversion at codon 272 (valine to leucine). Although members of another family were affected with leukemia, a 2-bp deletion in exon 6 was nonhereditary. The other two nonhereditary p53 mutations included a T to G transversion at codon 270 (phenylalanine to cysteine) and a G to C transversion at codon 248 (arginine to proline). These data support the role of both hereditary and acquired p53 mutations in the pathogenesis and/or progression of some cases of childhood acute lymphoblastic leukemia.
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PMID:Hereditary and acquired p53 gene mutations in childhood acute lymphoblastic leukemia. 173 52

Poly(amidoamine)s were synthesized by polyaddition reaction: to bis-acryloylpiperazine of piperazine (1), or N,N'-bis(2-hydroxyethyl)ethylenediamine (2), and to 2,2-bis(acrylamido)acetic acid of piperazine (3). Compound 2 was also end-capped with 4-hydroxythiophenol, thus introducing a terminal moiety suitable for radio-iodination using the chloramine T method (4). Such polymers behave as bases in aqueous solution, and their net average charge alters considerably as the pH changes from 7.4 to 5.5. This results in a change in polymer conformation which may prove useful in the design of polymeric drug delivery systems. However, their suitability for use in the organism will depend on polymer toxicity and also on their rate of biodegradation. Here we studied the biological properties of the above poly(amidoamine)s with a view to optimizing the synthesis of novel drug carriers. The general cytotoxicity of compounds 1, 2, 3, and 4 was examined in vitro using two human cell lines, hepatoma (HepG2) and a lymphoblastoid leukaemia (CCRF). Several different methods [the tetrazolium (MTT) test, [3H]leucine or [3H]thymidine incorporation, or counting cell numbers] were used to measure cell viability. Compounds 1, 2, and 4 were much less toxic to both cell lines than equivalent concentrations of the polycationic poly-L-lysine, and in no case did viability fall below 50% (concentrations up to 2 mg/ml). Although compound 2 was not markedly toxic to HepG2 cells, concentration-dependent toxicity was observed against CCRF cells. In this case, the polymer concentration decreasing viability by 59% (ID50) was approximately 50 micrograms/ml for compound 2 compared with an ID50 of approximately 10 micrograms/ml for poly-L-lysine. The rate of hydrolytic degradation of compound 2 was examined using viscometric measurements and gel permeation chromatography (GPC). After incubation at pH 7.5 and 8.0 for 24 h, polymer intrinsic viscosity was decreased by approximately 50% and GPC elution profiles showed a simultaneous increase in polymer retention time, indicating a fall in molecular weight. Hydrolytic degradation progressed much more slowly at pH 5.5. Compound 4 was also incubated with a mixture of isolated rat liver lysosomal enzymes (tritosomes) at pH 5.5, but no increase in the rate of degradation was observed.
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PMID:Poly(amidoamine)s with potential as drug carriers: degradation and cellular toxicity. 177 34


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