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)

An antigen crossreacting with the 30,000-molecular-weight protein (p30) of the feline endogenous oncornavirus (RD114) was detected in a well-characterized human fibrosarcoma cell line, HT1080, by indirect immunofluorescence. Three antisera against RD114 p30 gave similar positive results, while two antisera prepared against simian sarcoma virus p30, one antiserum prepared against murine leukemia virus p30, and one antiserum prepared against feline leukemia virus p30 gave no immunofluorescence. The reactivity observed with the antiserum against RD114 p30 was detected in 10-40% of the cells at early passages and was no longer expressed by the forty-first subculture. The reactivity could be removed by adsorption of the antiserum with RD114-infected dog or human cells, but not by uninfected cells or by cells infected with an antigenically unrelated oncornavirus, feline leukemia virus. Neither complete virus particles nor reverse transcriptase (RNA-dependent DNA nucleotidyltransferase) activity was detected in the culture. These experiments suggest that the fibrosarcoma cell line is expressing an antigen related to the p30 protein of RD114 baboon endogenous virus group of oncornaviruses without producing complete virions.
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PMID:Expression of antigenic crossreactivity to RD114 p 30 protein in a human fibrosarcoma cell line. 6 79

Leukemic cells of AKR mice contain as constituents of their membranes the murine leukemia virus envelope protein gp70 and the precursor polyprotein of the viral internal (core) structural proteins. Both gp70 and the core polyprotein are represented on the cell surface as glycoproteins, as evidenced by incorporation of [3H]glucosamine into their structure and the binding of these proteins to lectins. The glycosylated core polyprotein exists in at least two serologically distinguishable forms: the 95,000-dalton polyprotein reacts with antisera prepared against the viral proteins p30, p12, and p10, whereas the 85,000-dalton polyprotein reacts with antisera prepared against the viral proteins p30 and p12, but not p10. Additional heterogeneity in these cell surface polyproteins has been observed wtih leukemias induced by exogenous leukemia viruses. Spontaneous leukemia cells of AKR mice invariably express gp70 and the core polyprotein on their cell surface; normal thymocytes of young AKR mice express gp70, but not the core polyprotein on their surface.
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PMID:Viral proteins expressed on the surface of murine leukemia cells. 6 23

The existence of oncornavirus genetic information in human prostatic tissue was studied by assaying tissue extracts for products of viral gene expression (ie, the p30 antigen). Tissue samples from patients with benign prostatic hyperplasia (BPH) or prostatic carcinoma (CaP) were assayed by the competetive radioimmunoassay. The competing antigens used were p30 proteins derived from the simian sarcoma virus type-1 (SSV-1) and the Rauscher murine leukemia virus (RLV). Of the 40 extracts tested, three of 20 extracts from BPH patients and one of 20 from CaP patients competed with the SSV-1 p30 antigen and only one of ten extracts from BPH patients competed with the RLV p30 antigen. The significance of these findings has yet to be established.
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PMID:Role of oncornaviruses in carcinoma of the prostate. 6 18

Electron microscopic, immunologic, and biochemical methods have been used in an attempt to detect and characterize oncornaviruses in human prostatic carcinoma (PCa) and benign prostatic hyperplasia (BPH), and in prostates of mice of high and low mammary cancer or leukemia strains. Ultrastructural examination of 37 PCa and nine BPH specimens has revealed the presence of particles resembling type C virus in five cases of PCa and one of BPH, and also two different types of intracisternal virus-like particles in seven other cases of PCa. Type B virus particles have been observed in prostate of old mice of high mammary cancer strains, while type C virus particles have been found in the prostates of most mice of all the ten strains examined. Immunofluorescence tests with sera from patients with PCa and BPH and with cells derived in vitro from PCa have shown that sera of patients with PCa contained antibodies directed mainly against Forssman-like and tumor-related antigens. In immunofluorescence tests of antisera to major proteins of oncornaviruses with cells of PCa and BPH tissues grown in vitro, positive reactions have been obtained with antisera to p30 protein of murine, feline, and simian type C viruses. Fixed immunofluorescence (FIF) tests of sera of PCa (38%) and BPH (25%) and of some normal donors (27%) gave positive cytoplasmic reaction with mouse prostate cells infected with Soehner-Dmochowski murine sarcoma virus (SD-MSV). Immunoferritin tests of 11 sera positive by FIF gave ferritin labeling of type C virus particles in the SD-MSV-infected mouse prostate cells...
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PMID:Search for oncogenic viruses in human prostate cancer. 6 17

The reverse transcriptase was purified to homogeneity from Rauscher leukemia virus by sequential column chromatography on phosphocellulose and DNA-cellulose. The purified enzyme, a single polypeptide chain with a molecular weight of approximately 70,000, interacts with major internal protein p30 of the same virus. The reverse transcriptase - p30 complex stimulated [3H]TMP incorporation into (dT)12 - (rA)n 2- to 3-fold compared to that observed with the purified enzyme alone. Monospecific antiserum made against either p30 or reverse transcriptase precipitated the entire complex. The sedimentation rate of the reverse transcriptase - p30 complex is approximately 12 S as estimated by glycerol gradient centrifugation, and the molecular weight is approximately 400,000 by chromatography on a Sepharose 6B column. The complex dissociates into its original components when treated with 0.8 M KCl.
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PMID:Effect of Rauscher leukemia virus-specific proteins on reverse transcriptase. Binding between reverse transcriptase and p30. 6 27

The pP60gag polyprotein of the feline leukemia virus pseudotype of m1 Moloney murine sarcoma virus [m1MSV(FeLV)] was previously shown to be MSV specific and to contain murine p30 and smaller structural polypeptides. This protein was detected in m1MSV-transformed cells, and in pulse-chase studies it was found to be stable. In this study virion P60 was shown to contain murine pp12, to be phosphorylated, and to bind to nucleic acids. 32P-labeled m1MSV[FeLV) was fractionated by guanidine agarose chromatography and analyzed by gel electrophoresis. Both P60 and pp12 were found to be the major phosphoproteins, phosphorylated in both serine and threonine residues. Virion P60 bound preferentially to single-stranded DNA and RNA in a competition filter binding assay, using 125I-labeled single-stranded calf thymus DNA and various unlabeled nucleic acids. Similar phosphorylation and DNA binding properties were demonstrated for cellular P60. Thus, immunoprecipitation of cellular extracts showed that P60 was phosphorylated in both producer and nonproducer transformed cells, indicating that phosphorylation occurs independently of virus assembly. Moreover, P60 from cytoplasmic extracts was retained on single-stranded DNA-Sepharose columns, demonstrating that cellular P60 binds to DNA.
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PMID:Phosphorylation and nucleic acid binding properties of m1 Moloney murine sarcoma virus-specific pP60gag. 6 21

The Gross cell surface antigen (GCSA), associated with expression of endogenous Gross-type murine leukemia virus (G-MuLV) in tissues of mice, is defined by the cytotoxic reaction of a C57BL/6 antiserum, anti-AKR spontaneous leukemia K36, with cells of the Gross virus-induced C57BL/6 leukemia, Emale symbolG2. Sequential lactoperoxidase-catalyzed radioiodination of Emale symbolG2 cells, Nonidet P-40 lysis, precipitation with anti-K36 serum, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis identified molecules with properties of polyproteins encoded by the gag region of the viral genome. These cell surface species could also be labeled by in vitro culturing of Emale symbolG2 with radioactive glucosamine. The viral specificity of these molecules and their participation in the GCSA typing system were established as follows. (i) Absorption of anti-K36 serum with GCSA(+), but not GCSA(-), leukemias led to a marked decrease in precipitation of these proteins. (ii) The same Emale symbolG2 cell surface proteins were also precipitated by antisera against the MuLV virion proteins p30 and p15. (iii) Anti-K36 was shown to possess antibodies against Gross virus p30 and p15. (iv) "Clearing" the Emale symbolG2 lysate of molecules reactive with anti-p30 or anti-p15 sera removed molecules reactive with anti-K36 serum. (v) Absorption of anti-K36 serum with disrupted G-MuLV virions or with Gross p30 or p15 removed GCSA cytotoxic antibodies; partial absorption was achieved with disrupted Rauscher-MuLV (R-MuLV) or with R-MuLV p30, and no absorption was found with R-MuLV p15. These data show that Emale symbolG2 cells express, on their surfaces, MuLV core polyproteins that apparently can be glycosylated and on which the determinants of GCSA are located.
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PMID:Characterization of molecular species carrying gross cell surface antigen. 6 25

Two species of glycosylated type C viral core polyprotein were identified on the surface of AKR spontaneous leukemia cells. One of these cell surface polyproteins was shown by immunoprecipitation to have antigenic determinants of murine leukemia virus p30, p15, p12, and p10; the other had murine leukemia virus p30, p15, and p12, but not p10, determinants. Both species were also expressed on thymocytes from 6-month-old, preleukemic AKR mice.
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PMID:Two species of type C viral core polyprotein on AKR mouse leukemia cells. 6 29

Embryos of the 12th-20th day of gestation, newborn and adult AKR and BALB/c mice were investigated for the presence of mouse C-type virus major structural p30 protein (gs-1) and Gross leukemia virus type-specific antigen AGLV) by means of radioimmunodiffusion with test systems. The p30 protein was distinctly determined from the 12th day of intrauterine development in both mouse lines; it persisted in the embryo tissues until birth and was detectable also in the AKR and BALB/c mouse tissues from the first days of postnatal development and during the whole life. AGLV was not revealed in BALB/c and AKR embryos and in adult BALB/c mice; however it was found in the AKR newborn mice since the 1st-2nd day after birth. Basing on these data a conclusion was drawn that p30 protein and AGLV were expressed independently according to the radioimmuno-diffusion method sensitivity.
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PMID:[Detection of antigens of endogenous viruses of the C-type during mouse development]. 7 Feb 47

The effect of interferon on the rate of synthesis and the cleavage processing of viral proteins in mouse cells, chronically infected with Rauscher murine leukemia virus, has been studied by immunoprecipitation of newly synthesized viral proteins from virus-infected cells pulse-labeled with [35S]methionine. Immuno-precipitated, labeled polypeptides were resolved by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and then examined by autoradiography. Cleavage processing was studied in the same manner with cells that had been pulse-labeled and then incubated with non-radioactive media for a sufficient time to allow normal cleavage processing to occur. At a concentration that strongly inhibited the release of virus particles, interferon had no effect on the synthesis of proteins carrying antigenic determinants of the major core protein p30 or of the envelope glycoprotein gp69/71. Nor did it affect the post-translational cleavage processing of the precursors to these proteins. Similarly, interferon did not affect labeling or chasing of precursor protein carrying the p15 determinants; labeling of p15 itself could not be studied because it does not contain methionine.
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PMID:Synthesis and cleavage processing of oncornavirus proteins during interferon inhibition of virus particle release. 7 Apr 6


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