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)

Chronic myelogenous leukemia (CML) progenitors show decreased adhesion to stroma and fibronectin (FN) through beta 1 integrin receptors. We have previously shown that interferon-alpha (IFN-alpha) restores beta 1 integrin-mediated adhesion of CML progenitors to stroma. Because beta1 integrins transmit proliferation inhibitory signals from the microenvironment to normal hematopoietic progenitors, we hypothesized that decreased integrin-mediated adhesion of CML progenitors contributes to their continuous proliferation when in contact with stroma and that IFN-alpha treatment, by restoring integrin-mediated adhesion, also restores integrin-mediated microenvironmental inhibition of CML progenitor proliferation. We show here that, in contrast to normal colony-forming cells (CFC), the percentage of malignant CML CFC in S-phase was not significantly reduced following coculture with stromal layers. However, IFN-alpha treatment resulted in a significant reduction in the proliferation of CML CFC on coculture with stroma. This effect was not because of a direct antiproliferative effect of IFN-alpha on CML CFC because the proliferation of IFN-alpha treated CML CFC kept in suspension culture was not reduced. We examined the role of restored signaling through beta 1 integrin receptors in IFN-alpha induced inhibition of CML progenitors in two sets of experiment. In the first set of experiments, we demonstrated that proliferation of IFN-alpha-treated CML CFC, but not untreated CML CFC, was significantly reduced following coculture with 33/66-kD and 75-kD FN fragments, recognized by alpha 4 beta 1 and alpha 5 beta 1 integrins respectively. In a second set of experiments, we demonstrate that direct stimulation of integrin receptors by crosslinking with blocking antibodies to alpha 4, alpha 5, and beta 1 integrins and secondary goat antimouse antibodies resulted in significant reduction in proliferation of normal and IFN-alpha treated CML progenitors but not untreated CML CFC. These studies indicate that CML hematopoietic progenitors are unresponsive to beta 1-integrin mediated proliferation inhibition and that IFN-alpha not only restores beta 1 integrin-mediated adhesion but also beta1-mediated microenvironmental inhibition of CML progenitor proliferation. These observations may explain, at least in part, the therapeutic efficacy of IFN-alpha in CML.
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PMID:Interferon-alpha restores normal beta 1 integrin-mediated inhibition of hematopoietic progenitor proliferation by the marrow microenvironment in chronic myelogenous leukemia. 861 16

The author engaged himself in the studies of ABO blood group system for the last three decades, and reviewed the progresses in this period, which were classified into following 5 items. 1. H-, A- and B-active oligosaccharides were isolated from the globoside fractions from human erythrocytes by ozonolysis. One of the H-active oligosaccharide with short carbohydrate chain is a pentasaccharide: Fuc(alpha 1-->2)Gal(beta 1-->4)GlcNAc(beta 1-->3)Gal(beta 1-->4)Glc, and the other with long carbohydrate chain is a heptasaccharide: Fuc(alpha 1-->2)Gal(beta 1-->4)GlcNAc(beta 1-->3)Gal(beta 1-->4)GlcNAc(beta 1-->3)Gal(beta 1-->4)Glc. Hexa- or octasaccharides with blood group A- or B-activity have an additional alpha-N-acetylgalactosaminyl residue or alpha-galactosyl residue, which joints with alpha 1-->3 linkage to subterminal beta-galactose of the both of H-active oligosaccharides, respectively. 2. A blood group A-gene specified alpha-N-acetyl-galactosaminyltransferase (A-enzyme) catalyzes the transfer of N-acetylgalactosamine from the UDP-sugar to the subterminal beta-galactosyl residue of blood group H-active carbohydrate chain, and a blood group B-gene specified alpha-galactosyltransferase (B-enzyme) catalyzes the transfer of galactose from the UDP-sugar to the subterminal beta-galactosyl residue of blood group H-active carbohydrate chain, respectively. Either the A- or B-enzyme can not transfer the substrate sugar to the carbohydrate chain lacking alpha-fucosyl residue of H-determinant, and it is the reason why the synthesis of blood group A- or B-antigenic structure in inhibited in the tissues of Bombay phenotype and in the secretory glands of the nonsecretor. 3. Specific antibody either to the A- or B-enzyme can be introduced in the serum of the rabbit which was immunized with the A- or B-enzyme preparation, respectively. And immunological cross reaction is also present between the A- and B-enzyme, but the immunologically cross reactive material can not be found in the blood group O individual. The absence of immunologically cross reactive material in the blood group O individual is supported by a fact that the cross reactive antibody similar to the antibody in rabbit serum was present in the serum of the chronic myeloid leukemia patient, who was belonged to blood group B and treated with blood group incompatible bone marrow transplantation from blood group O donor, because it is acceptable to speculate that the grafted lymphocytes react to the B-enzyme in the recipient and produce the anti-enzyme antibody. 4. The immunological profiles described above are compatible with the cDNA structures of human blood group ABO alleles presented by Yamamoto F. et al. Their gene model is that the cDNAs of blood group ABO alleles are highly homologous, but the cDNA of common O allele is non-functional due to a single nucleotide deletion close to the 5'end of the coding sequence, which causes a frame shift of the codon, and results in truncated peptide. 5. Transcription of the human blood group ABO gene can be enhanced by a CBF/NF-Y which binds the minisatellite on the 5'-upstream sequence of the gene.
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PMID:[Past and present studies on ABO blood group system]. 1007 71

To investigate whether ABL specific tyrosine kinase specific inhibitor STI571 can restore beta1 integrin mediated negative effect on Ph(+) chronic myeloid leukemia(CML), the inhibitory effect of beta 1 integrin activator (beta1 integrin activating antibody 8A2, cytokines such as GM-CSF, G-CSF and SCF) and/or FN on the granulocyte-macrophage colony forming unit (CFU-GM) from 16 patients with Ph(+)CML and 13 normal individuals were examined; the bone marrow mononuclear cells (BMMNC) before and after ABL kinase specific inhibitor STI571 pretreatment (0.1 micro mol/L for 30-60 minutes) were target cells in this study. The roles which VLA4 and VLA5 played in this process were evaluated through blocking assay. The results showed: (1) beta1 integrin activator(s) or FN alone have no effect on CFU-GM from CML or normal bone marrow mononuclear cells before or after STI571 pretreatment, nor STI571 pretreatment itself. (2) The inhibitory effect of beta1 integrin activator(s) plus FN on CML CFU-GM are significantly lower than that on normal CFU-GM. (3) The inhibitory effect of beta1 integrin activator(s) plus FN on CML CFU-GM after STI571 pretreatment is comparable to that on normal CFU-GM. (4) Monoclonal antibody to VLA4 and VLA5 or to total beta1 integrins almost completely abrogate the above effect of STI571. The results suggested enhancing beta1 integrin mediated negative effect on myeloid progenitors in Ph(+)CML is one of the therapeutic mechanisms of STI571 on Ph(+)CML.
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PMID:[Low Concentrations of STI571 Enhances beta1 Integrin Mediated Inhibitory Effect on Proliferation of Myeloid Progenitors in Ph(+)Chronic Myeloid Leukemia] 1257 90

According to our previous experiments, Ph(+) chronic myeloid leukemia (CML) cell line K562 cells have defects in beta 1 integrin activation. In order to search the same regularity in Ph(+) CML bone marrow cells, bone marrow mononuclear cells (BMMNC) from 12 cases of Ph(+) CML and 10 cases of normal individuals were studied. Their expression rate of 9EG7 epitope on beta1 integrin post treatment by 8A2 or GM- or G-CSF and cell adhesion ability with soluble fibronectin (FN) were evaluated by flow cytometry; in addition, the effects of CGP57148B, a highly specific ABL tyrosine kinase inhibitor, were observed. Our results showed that 9EG7 expression rate and FN binding rate were very low in all the inactivated cells. The parameter increased markedly post 8A2 activation in both NBMMNCs and CMLBMMNCs, but the degree of increase in CMLBMMNCs was significantly lower than that in NBMMNCs; GM-CSF or G-CSF could significantly increase the parameters in NBMMNCs while had no effects on that in CMLBMMNCs. CGP57148B could increase the beta1 integrin activation potential of CMLBMMNCs but had no effects on that of NBMMNCs. The results indicate that decreased activation potential of beta1 integrin in CMLBMMNCs is the major cause of adhesion defects of Ph(+) CML cells; beta1 integrin functional insufficiency in CMLBMMNCs could not be directly reversed by ABL tyrosine kinase inhibitor CGP57148B.
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PMID:[beta1 Integrin Dysfunction in Adult Chronic Myeloid Leukemia Bone Marrow Cells] 1257 92


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