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)

Tumor-associated surface antigens (TASA) on a Moloney leukemia virus (M-MuLV)-induced lymphoma, MBL-2, in C57BL/6 mice (B6) were characterized. The surface proteins of MBL-2 cells were selectively radioiodinated and then extracted by Nonidet P40. The solubilized materials were then reacted with a variety of antisera: monospecific antisera to murine leukemia viral proteins (anti-gp69/71, anti-p30, anti-p15, anti-p12 and anti-p10), sera from B6 which regressed murine sarcoma tumors induced by murine sarcoma virus (anti-MSV) and a rabbit anti-MBL-2 antiserum. The resulting radioimmune precipitates were analyzed and compared in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The following results were obtained. (1) Among all anti-viral protein antisera tested only anti-gp69/71 was active and detected a protein doublet of gp69/71 and its degradation fragments of 42,000 and 35,000 daltons. (2) Radioimmune precipitates prepared with anti-MSV showed a SDS-PAGE pattern similar to that seen with anti-gp69/71. This result indicated that the surface antigen detected by the anti-MSV serum on MBL-2 tumor cell was probably a viral envelope antigen. (3) The rabbit anti-MBL-2 serum detected on the cell membrane an antigen of approximately 95,000 daltons which was tumor-associated and did not appear to be related to virion components. The anti-MBL-2-serum still reacted with the 95,000 dalton antigen after absorption with disrupted M-MuLV virus and with gp69/71 and p30 purified from the virus.
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PMID:Immunochemical characterization of tumor-associated surface antigens on a Moloney leukemia virus-lymphoma, MBL-2. 52 73

Preparations of Rauscher leukemia virus (RLV) that had relatively low, intermediate, or high levels of P70 (the gag gene product) on sodium dodecyl sulfatepolyacrylamide gel electrophoresis were examined by thin-section electron microscopy. A direct correlation was found between the number of immature virions in the RLV preparation and the amount of P70. The immature core subparticles isolated from these RLV preparations could themselves be further subdivided into two categories, based on their P70 content and negative stain morphology. Those immature cores containing a high P70/p30 ratio predominantly (85%) exhibited a highly coiled internal structure; those with a relatively low level of P70 exhibited less of an internal coiled structure.
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PMID:Rauscher leukemia virus populations enriched for "immature" virions contain increased amounts of P70, the gag gene product. 62 82

The synthesis and processing of virus-specific precursor polypeptides in NIH/3T3 cells infected at the permissive temperature (31 degrees C) with temperature-sensitive (ts) mutants of Rauscher murine leukemia virus was studied in pulse-chase experiments at the permissive and nonpermissive (39 degrees C) temperatures. The newly synthesized virus-specific polypeptides were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis after immunoprecipitation with polyvalent and monospecific antisera against Rauscher murine leukemia virus proteins. In cells infected with ts mutants defective in early replication steps (the early mutants ts17 and ts29), and ts mutants defective in postintegration steps (the late mutants ts25 and ts26), the processing of the primary gag gene product was impaired at the nonpermissive temperature. gag-pr75 of all four mutants was converted into gag-pr65; however, gag-pr65 accumulated at the nonpermissive temperature, and the main internal virion polypeptide p30 was not formed. Therefore, the proteolytic cleavage is blocked beyond gag-pr65. Concomitantly, the formation of the env gene-related polypeptide p12(E) of all four mutants was blocked at the restrictive temperature. In contrast, cells infected with the late mutant ts28, which produced noninfectious virions at 39 degrees C, showed a normal turnover of the gag and env precursor polypeptides.
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PMID:Impaired processing of precursor polypeptides of temperature-sensitive mutants of Rauscher murine leukemia virus. 62 83

Dietary administration of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide to mice for 14 weeks followed by 16 weeks of control diet resulted in a high incidence of lymphocytic leukemia and a low incidence of forestomach squamous cell papillomas. The coadministration of p-hydroxyacetanilide at a dose of 1.0% with either 250 or 500 ppm of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide resulted in inhibition of leukemogenesis, whereas when p-hydroxyacetanilide was coadministered with 1000 ppm of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide the leukemia incidence was not significantly reduced, but the latent period was prolonged. When sodium sulfate was administered with p-hydroxyacetanilide and N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide, leukemogenesis was partially restored. L-Methionine, fed in place of sodium sulfate, unblocked leukemogenicity inhibition by p-hydroxyacetanilide. None of these chemicals, p-hydroxyacetanilide, sodium sulfate, or L-methionine, significantly affected the incidence of forestomach papillomas induced by N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide, although tumor incidences in all groups were low. p-Hydroxyacetanilide and sodium sulfate had no significant effect on the high incidence of stomach tumors induced by formic acid 2-[4-(5-nitro-2-furyl)-2-thiazolyl]hydrazide or bladder tumors induced by N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide.
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PMID:Effect of p-hydroxyacetanilide, sodium sulfate, and L-methionine on the leukemogenicity of N-[4-(5-nitro-2-furyl)-2-thiazolyl]acetamide. 63 67

A preparative method for isolating pure viral envelopes from a type-C RNA tumor virus, Rauscher murine leukemia virus, is described. Fractionation of virions of Rauscher murine leukemia virus was studied after disruption of the virions with the detergents sodium dodecyl sulfate of Nonidet P-40 in combination with ether. Fractionation was performed through flotation in a discontinuous sucrose gradient and, as appeared from electron microscopic examination, a pure viral envelope fraction was obtained in this way. By use of sensitive competition radioimmunoassays or sodium dodecyl sulfate-polyacrylamide gel electrophoresis after immunoprecipitation with polyvalent and monospecific antisera directed against Rauscher murine leukemia virus proteins, the amount of the gag and env gene-encoded structural polypeptides in the virions and the isolated envelope fraction was compared. The predominant viral structural polypeptides in the purified envelope fraction were the env gene-encoded polypeptides gp70, p15(E), and p12(E), whereas, except for p15, there was only a relatively small amount of the gag gene-encoded structural polypeptides in this fraction.
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PMID:Structural studies on Rauscher murine leukemia virus: isolation and characterization of viral envelopes. 70 39

Compound 21 (N10-methyl-4-thiofolic acid) and related compounds were prepared as potential inhibitors of the cofactor forms of tetrahydrofolate. The preparation of 2-acetylamino-4-(benzylthio)-6-chloro-5-nitropyrimidine (4) provided an intermediate that was allowed to react with methyl p-[(3-aminoacetonyl)methylamino]benzoate oxime (16). The oxime function of the resulting 6-substituted aminopyrimidine 6 was hydrolyzed to give the corresponding acetonylaminopyrimidine 7, which on reductive cyclization gave methyl p-[[[2-amino-4-(benzylthio)-7,8-dihydro-6-pteridinyl]methyl]methylamino]benzoate (9). This dihydropteridine was oxidized with potassium permanganate, and the product was treated successively with sodium hydrosulfide to replace the benzylthio group and with aqueous sodium hydroxide to hydrolyze the ester function to give p-[[(2-amino-3,4-dihydro-4-thioxo-6-pteridinyl)methyl]methylamino]benzoic acid (N10-methyl-4-thiopteroic acid, 12). Another route to 12 involved the interaction of 2,5-diamino-4,6-dichloropyrimidine (15) with 16 to give methyl p-[[(2-amino-4-chloro-7,8-dihydro-6-pteridinyl)methyl]methylamino]benzoate (13). Displacement of the chloro group of 13 with sodium hydrosulfide followed by the simultaneous air oxidation of the dihydropteridine ring and saponification of the ester group gave 12. After protection of the 2-amino and 4-thioxo moieties of 12, the resulting intermediate benzoic acid was coupled with diethyl L-glutamate. The product of this reaction was deblocked to give 21. Methylation of 21 gave the corresponding 4-(methylthio) derivative 22, which on reaction with hydrazine gave the 4-hydrazino analog 23 of methotrexate. Reduction of 12 and 21 with sodium hydrosulfite gave the dihydropteridines 24 and 25, respectively. The title compound was an excellent inhibitor of the growth of Streptococcus faecium ATCC 8043. However, this and related compounds were ineffective inhibitors of dihydrofolic reductase and showed no significant activity in either the KB cell culture screen or against L1210 leukemia cells in mice.
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PMID:Synthesis of N-10-methyl-4-thiofolic acid and related compounds. 80 32

Rat basophilic leukemia cells were labeled either enzymically with 125I or biosynthetically by culture in the presence of 14C-glucosamine or 3H-amino-acids and then extracted with NP-40. IgE-anti-IgE precipitates insolubilized a radiolabeled macromolecule from these extracts largely or entirely absent in control IgG-anti-IgG percipitates. When specific precipitates were boiled in sodium dodecyl sulfate (SDS) and analyzed by polyacrylamide gel electrophoresis in the presence of SDS, most of the 14C or 125I radioactivity was in the area corresponding to an apparent m.w of 60,000 to 70,000 in 5.9% gels. In 10% and 12% gels, faster mobility was demonstrated indicating an atypical electrophoretic behavior often associated with glycoproteins and a presumptive m.w. of 50,000 or less. Since only IgE-containing precipitates localized label in this region and since such precipitates from cells saturated with IgE prior to surface iodination failed to show this band, the labeled macromolecule appears to be the IgE receptor itself. Analysis of the acid hydrolysates of precipitated 14C radioactivity demonstrated that label was entirely in hexosamines and sialic acid. 125I and 14C labels in the recepotr region were eliminated almost completely with pepsin and pronase and to a lesser extent with trypsin.
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PMID:The rat basophilic leukemia cell receptor for IgE. I. Characterization as a glycoprotein. 82 Aug 4

Either inhibition or enhancement of the spontaneous lymphoma exhibited by AKR mice was observed after treatment with different dosages of the sulfhydryl inhibitor, sodium iodoacetate. Treatment of the mice at 3 or 6 months of age with five ip injections of 0.10 mg of iodoacetate at 5-day intervals significnatly extended the survival of the animals. A single administration of this dosage elevated the responses of splenic lymphocytes to the T-cell mitogens phytohemagglutinin (PHA) and concanavalin A (Con A), and resulted in higher PHA and Con A response ratios than were noted for age-matched controls. Conversely, groups of 3- or 6-month-old AKR mice, subjected to the same regimen but with 0.01-mg dosages, exhibited an apparent accelerated development of the leukemia and survived for significantly shorter periods. In general, splenic lymphocytes harvested from mice given a single 0.01-mg treatment of iodoacetate were not as reactive as were control cell cultures when exposed to the T-cell mitogens.
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PMID:Iodoacetate-induced inhibition and enhancement of spontaneous leukemia in AKR mice. 85 29

A method is described for radioiodination to high specific activity of fixed and stained proteins within sodium dodecyl sulfate-polyacrylamide gels, without elution of the proteins from the gel. Following radioiodination, the proteins can be removed from the gel by trypsin treatment and the peptides analyzed. This procedure offers a means to structurally compare the proteins of multicomponent systems when purification of each component to homogeneity is unfeasible. Using this technique, we have compared the tryptic peptides of all the major protein components of Moloney and Rauscher leukemia viruses using only 50 to 100 microgram of total protein from each virus. Additionally, we have analyzed the membrane proteins of Dictyostelium discoideum at various stages in development. The validity of the technique and its value as a tool for comparative studies and identification of precursor-product relationships is discussed.
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PMID:Radioiodination of proteins in single polyacrylamide gel slices. Tryptic peptide analysis of all the major members of complex multicomponent systems using microgram quantities of total protein. 89 22

Rauscher murine leukemia virus glycoprotein gp69/71 and non-glycosylated p15(E) are synthesized by way of a 90,000-dalton precursor glycoprotein, termed Pr2a+b. Peptide mapping experiments showed that Pr2a+b contains all the tyrosine-containing tryptic peptides of gp69/71. Two additional tyrosine-containing tryptic peptides in Pr2a+b that are not detected in gp69/71 are found in p15(E). Thus, gp69/71 and p15(E) peptide sequences account for all the tyrosine tryptic peptides of Pr2a+b. The gene order of the two proteins was determined by pulse-labeling infected cells in the presence and absence of pactamycin at concentrations of the inhibitor that prevent initiation of translation, but not elongation. The gene order was found to be: (2)HN-gp69/71-p15(E)-COOH. A newly identified major viral protein, termed p12(E), migrates in sodium dodecyl sulfate-polyacrylamide gels in the "p12" region. It is related to p15(E) as determined by tryptic mapping experiments. p15(E) and p12(E) are not phosphorylated, and both can be separated from phosphoprotein p12 by guanidine hydrochloride-agarose chromatography. p12(E) and p15(E) elute in the void volume fraction, whereas phosphoprotein p12 elutes between p15 and p10. The two p12 proteins can also be separated from each other by two-dimensional gel electrophoresis involving isoelectric focusing in the first dimension and sodium dodecyl sulfate-gel electrophoresis in the second dimension.
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PMID:Common precursor for Rauscher leukemia virus gp69/71, p15(E), and p12(E). 89 95


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