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)

Multiple forms of RNA polymerases (I, II and III) from murine leukemia L1210 cells are solubilized, purified and characterized. Heterogeneity of RNA polymerases I and III is revealed by chromatography on DEAE-Sephadex and Phosphocellulose (P-11). The properties of these forms such as peculiarities of transcription of native and denaturated DNA, metal ion dependence (Mg2+, Mn2+ and (NH4)2SO4) and alpha-amanitin sensitivity resemble those reported for other mammalian RNA polymerases. The level of RNA polymerase I of leukemia L1210 cells increase approximately ten-fold relative to its level in some organs of healthy mice.
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PMID:[RNA-polymerase of murine leukemia L1210 cells]. 62 42

The amount of free purine and pyrimidine ribonucleotides in the spleens of mice (C57Bl and DBA/2) and in lympholeukemia cells (La and L1210), sensitive and with induced resistance to 5-fluorouracil, was determined by chromatography on a column with DEAE-cellulose. It was found that the cytidine ribonucleotide pool in the spleens of DBA/2 mice is 2 times lower as compared to C57Bl mice. The lympholeukemia cells (La and L1210) isolated from the animals also differed in their uridine nucleotide pools. The development of leukemia was accompanied by a decrease in ATP and GTP. No significant changes in the total amount of pyrimidine nucleotides under developing resistance to 5-fluororuacil were observed.
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PMID:[Comparison of free ribonucleotide pool in the spleens of C57BL and DBA/2 mice and in leukemia cells sensitive and resistant to 5-fluorouracil]. 62 43

The anti-tumour activity induced by glucans (lentinan, yeast cell walls, pseudonigeran, dextran, DEAE-dextran and dextran sulphate) and fructosans (levan and carboxymethyl-levan) was compared with the activity of C. parvum. The following effects on tumour systems in CBA mice were assayed: (a) adjuvant activity on the immune response against tumour-specific transplantation antigens (TSTA) with a methylcholanthrene-induced fibrosarcoma; (b) cytostatic activity of peritoneal macrophages against radiation-induced leukaemia cells; and (c) inhibition of tumour nodule formation in the lungs following i.v. injection of fibrosarcoma cells. All the polysaccharides induced cytostatic macrophages, but the dextrans and levans did so only after i.p. and not i.v. injection. Only lentinan, yeast cell walls and pseudonigeran were active in the lung-nodule inhibition test; and only lentinan and dextran sulphate showed slight adjuvant activity for TSTA. It is concluded that the anti-tumour activity induced by these polysaccharides is predominantly non-specific macrophage-mediated and much weaker than that found with C. parvum.
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PMID:Mechanism of the anti-tumour effect of glucans and fructosans: a comparison with C. parvum. 88 84

32P- and methyl-3H-labeled 70S Moloney murine leukemia virus RNA was purified from virions produced in Moloney murine leukemia virus-infected mouse embryo cells. Primer-free RNA subunits obtained by heat treatment and zonal centrifugation were digested with RNase T2, and methylated oligonucleotides were chromatographed on DEAE-Sephadex in 7 M urea. Approximately one molecule of RNase T2-stable oligonucleotide (-5 charge) was isolated per subunit. Structural analysis indicated that the sequence of the oligonucleotide is m7GpppGmpCp. Analysis of the mononucleotide fraction isolated by DEAE-Sephadex chromatography of the RNase T2 digest identified 15 to 23 internal N6-methyladenylic acid molecules per subunit.
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PMID:Methylation pattern of genomic RNA from Moloney murine leukemia virus. 97 37

Considerable skin-reactive and macrophage-disappearance-inducing activities were detected in cell-free fluids of 2 mouse ascites tumors (Ehrlich ascites tumor, leukemia L 1210). Fractionation of the supernatants by ammonium sulfate precipitation, gel filtration on Sephadex G-200, and DEAE-Sephadex A-50 column chromatography resulted in characterization of the proteinaceous substance which accounts for skin-reactive activity. The factor responsible bears a close physicochemical and biological resemblance to the skin-reactive factor of lymphocytic origin which is known to be generated by specific or nonspecific stimulation of lymphocytes in vitro, or to be produced spontaneously by lymphoblastoid cell lines. The biological significance of the findings is discussed.
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PMID:Presence and characterization of lymphokines in mouse ascites tumor fluids. 100 14

The RNA polymerase activities from the nuclei of the spleen of uninfected and Rauscher murine leukemia virus-infected NIH Swiss mice were resolved by DEAE-cellulose column chromatography, and their properties were compared. The RNA polymerase activities from infected and uninfected spleens were the same with respect to column elution profiles, optimum requirements for various salts, ratios of activities with Mn2+ and Mg2+, sedimentation values, and response to most templates. With the exception of minor differences in activities with certain DNA templates, the significance of which is not clear, no qualitative differences in the enzymes from these two sources were found, but an increase in the specific activity of the alpha-amanitin sensitive enzyme, RNA polymerase II, was found in the leukemic spleen. These preliminary results suggest that there may be no novel RNA polymerase induced by Rauscher murine luekemia virus-infection, and they are in keeping with the interpretation that the viral DNA genome is transcribed by a host RNA polymerase.
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PMID:Deoxyribonucleic acid-dependent ribonucleic acid polymerases from spleen of uninfected and Rauscher murine leukemia virus-infected NIH Swiss mice.? 112 31

1. The properties of ferritin in serum have been compared with those of ferritin from a number of tissues including blood cells. On anion-exchange chromatography with DEAE-Sephadex, the behaviour of human heart ferritin is different from that of liver, kidney or spleen ferritin. Reticulocyte ferritin appears to have similar characteristics to heart ferritin. 2. Serum ferritin from normal subjects and patients with various degrees of iron load, leukaemia or liver disease all have a much lower affinity for the anion-exchange column that any tissue ferritin, suggesting a difference in isoelectric point. The elution point of serum ferritin from patients with acute myeloblastic leukaemia is significantly different from normal. 3. Density gradient centrifugation in sucrose showed that ferritin in leucocyte extracts and partially purified ferritin from the serum of two patients with iron overload behaved as apoferritin rather than the iron-rich protein. 4. The results suggest that ferritin is modified during its entry into the plasma and that even in cases of iron overload the iron content of serum ferritin may be low. The findings are of importance in considering the origin of plasma ferritin, the clearance of ferritin from plasma and its role in iron metabolism.
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PMID:The characteristics of ferritin from human tissues, serum and blood cells. 116 59

A pyrimidine phosphoribosyltransferase, previously shown to utilize 5-fluorouracil and possibly also uracil and orotate (Reyes, P. (1969) Biochemistry 8, 2057-2062), has been purified about 100-fold from murine leukemia P1534J. Roughly 20% of the original activity was recovered to yield an enzyme preparation with a specific activity of 7.4 mumol of 5-fluorouracil utilized/hour/mg of protein. Disc gel electrophoresis of this preparation revealed the presence of a major band of protein accompanied by several trace contaminants. Emphasis was placed on a study of the substrate specificity of this enzyme. 5-Fluorouracil, uracil, and orotate phosphoribosyltransferase activities purified in parallel during fractionation with ammonium sulfate and protamine sulfate and eluted together from columns of Sephadex tG-150 and DEAE-cellulose. The three phosphoribosyltransferase activities eluted from the Sephadex columns with an apparent molecular weight of 55,000 to 60,000. In spite of this coordinate fractionation, preferential losses of orotate activity were experienced during DEAE-cellulose chromatography. Orotate activity continued to behave in a unique manner under other conditions, such as during proteolytic digestion. In the latter case, however, all three activities responded in parallel when digestion took place in the presence of 5mM UMP. The following results provided additional evidence to support the view that all three phosphoribosyltransferase activities may be catalyzed by the same enzyme: (a) the apparent Km for 5-phosphoribosyl 1-pyrophosphate (PP-ribose-P) did not change significantly when enzyme activity was measured with either 5-fluorouracil, uracil, or orotate; (b) 5-fluorouracil and uracil were found to be mutually competitive inhibitors; the effect of 5-fluorouracil on orotate activity was likewise competitive in nature; (c) in the absence of UMP, orotate was a noncompetitive inhibitor of 5-fluorouracil and uracil activities, but in the presence of 5mM UMP it became a competitive inhibitor of both of these activities; (d) 5-fluorouracil and orotate activities co-sedimented in 5 to 20% sucrose gradients (uracil activity was not examined); and (e) a wide variety of normal mouse tissues displayed virtually the same 5-fluorouracil to uracil to orotate activity ratio as found in P1534J enzyme preparations. The apparent Km and Ki values reported in this study indicate that the preferred pyrimidine substrate is orotate. It seems likely, therefore, that this enzyme functions in vivo as an orotate phosphoribosyltransferase. Orotate phosphoribosyltransferase and orotidine 5'-monophosphate (OMP) decarboxylase activities (a) eluted together during gel filtration on Sephadex G-150, (b) co-sedimented in 5 to 20% sucrose gradients, (c) remained associated during fractionation with ammonium sulfate and protamine sulfate, and (d) separated into a phosphoribosyltransferase and decarboxylase component when enzyme preparations previously subjected to limited proteolysis by elastase were sedimented in sucrose gradients...
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PMID:Studies on a pyrimidine phosphoribosyltransferase from murine leukemia P1534J. Partial purification, substrate specificity, and evidence for its existence as a bifunctional complex with orotidine 5-phosphate decarboxylase. 117 Oct 96

The murine thymus leukemia antigen (TL) has been solubilized from the tumor ASL1 and from an established cell line ASL1W, by papain digestion. When a 15-min digest was chromatographed on Sephadex G-200, two peaks of TL activity were eluted with apparent molecular weights of approximately 58,000 and 31,000. Chromatography of a 30-min digest under the same conditions resulted in elution of a single peak of activity with an apparent molecular weight of 58,000. Additional purification was carried out on the 58,000 molecular weight material by absorption to, and elution from DEAE-cellulose. The combination of gel filtration and ion exchange chromatography resulted in approximately a 150-fold purification.
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PMID:Purification of murine thymus leukemia antigen (TL). A quantitative assessment of limited proteolysis. 118 18

Biotin derivatives of methotrexate (biotin-SS-MTX) and folate (biotin-SS-folate), in which the functional components are joined by a dissociable disulfide-containing spacer, have been synthesized, purified by DEAE-Trisacryl chromatography, and characterized by HPLC, elemental analysis and mass spectrometry. These compounds provide a convenient means for the single-step purification of the folate transporters from L1210 cells. Parental L1210 murine leukemia cells, which contain only the microM transporter (the reduced folate/MTX transport protein) were treated with the N-hydroxysulfosuccinimide ester of biotin-SS-MTX, and a detergent extract of the plasma membranes was exposed to streptavidin-agarose beads to adsorb the labeled protein. Dithiothreitol cleavage of the disulfide linkage released the transporter, which migrated as a well-defined component (43 kDa) on SDS-PAGE gels; no other proteins were present. An L1210 subline (JF), obtained by adapting cells to grow on nanomolar concentrations of folate, contains both the microM transporter and the nM transporter (high-affinity folate binding protein). When these cells were treated with the N-hydroxysulfosuccimide ester of biotin-SS-folate and processed as described above, analysis on SDS-PAGE gels revealed the presence of two proteins, the microM transporter (43 kDa) and the nM transporter (39 kDa). Both transporters were characterized with respect to amino acid content; blocked N-termini precluded Edman sequencing. Treatment of the nM transporter with peptide:N-glycosidase F produced a smaller component (32 kDa); the microM transporter, conversely, was unchanged by this procedure. When the microM transporter in parental L1210 cells was labeled with fluorescein-MTX and then treated with phosphoinositol-specific phospholipase C (PI-PLC), no change in fluorescence was detected. Alternatively, when the nM transporter in the JF subline was labeled with fluorescein-folate and then treated with PI-PLC, complete loss of fluorescence was observed. These results indicate that the L1210 microM transporter is a non-glycosylated, integral membrane protein, while its nM counterpart is heavily glycosylated and anchored exofacially to the membrane by a glycosylphosphatidylinositol component.
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PMID:Multiple folate transport systems in L1210 cells. 132 5


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