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)

Soluble extracts from Moloney virus-induced leukemia cells were shown to contain immunogenic and immunosuppressive components. Immunogenic components were divided into two classes based on their ability to :(1) combine with humoral antibody to inhibit cytotoxic activity; or (2) stimulate blastogenesis in normal syngeneic lymphocytes. Immunosuppressive components were demonstrated by the inhibition of DNA synthesis in normal syngeneic lymphocytes and suppression of a mixed lymphocyte reaction. Stimulating components in many soluble preparations were completely masked by immunosuppressive components. However, all three components could be resolved by Sephadex G200 chromatography.
Int J Cancer 1976 May 15
PMID:Immunogenic and immunosuppressive components in soluble preparations from Moloney murine leukemia virus-induced tumor cells. 5 37

In accordance with a memorandum of understanding in cancer research between scientists in the USSR and the USA, virological studies were performed on two baboons from the Russian colony at the Institute of Experimental Pathology and Therapy at Sukhumi where several cases of leukemia have been observed over the past few years. Foamyvirus isolations were made from lymphoid cells of both of these monkeys, one of which had a confirmed case of lymphoma. The isolates were similar to each other serologically and morphologically, possessed characteristics typical of foamyviruses, and cross-reacted to a low level with antibody to simian foamyvirus type 1.
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PMID:Virological studies of baboon (Papio hamadryas) lymphoma: isolation and characterization of foamyviruses. 5 63

Somatic cells of vertebrates contain gene sequences which are an integral part of chromosomal DNA and which code for the production of complete type C RNA viruses. These virogenes are genetically transmitted from parent to progeny along with other cellular genes (virogene-oncogene hypothesis). Activation of this endogenous virogene information from a normally repressed state, rather than infection by exogenous oncogenic viruses, has been proposed as the most common mechanism of cancer causation in animals, including man. Recent isolates of baboon type C RNA viruses, while related morphologically and biochemically to other mammalian type C RNA viruses, can be distinguished by nucleic acid hybridization and immunologic criteria. Within primates, type C virogenes have evolved as the species have evolved; virogenes from closely related genera and families have the closest gene sequence homology. Endogenous viruses from one species may infect animals of a distantly related species and become incorporated into their germ line. Genomes of exogenous viruses, such as the murine leukemia viruses, which are infectious from animal to animal within the same species, evolve more rapidly than the endogenous virogenes which replicate solely as cellular genes. A major viral structural protein of baboon type C RNA viruses, p30 was detected by radioimmunoassay in normal primate tissues. Radioimmunoassays have also detected p30 antigen in human tissues which appear to be immunologically related to primate viral p30. Hybridization experiments have confirmed that type C viral sequences are also present in the human genome.
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PMID:Type C virogenes: genetic transfer and interspecies transfer. 5 81

A new antigan has been revealed by means of antisera against Rauscher virus in mice with Rauscher virus-induced leukemia. This antigen appears to be different from both Rauscher type-specific antigen and MULV-gs-1 (p-30), as shown by studies of electrophoretic mobility and immunochemical specificity. Except in leukemic mice it was also found in low levels in both serum and spleen extracts of healthy mice of a number of strains. Furthermore, this antigen was regularly demonstrated by immunofluorescence on the surface of erythroblasts, but not on the surface of erythrocytes, lymphocytes, polymorphonuclear cells and thymocytes, and was shown to be different from fetal hemoglobin. Therefore, it is referred to as antigen of erythroblasts (Ag-Eb), which seems to represent a surface marker for a certain differentiation stage of erythroid cells.
Int J Cancer 1976 Jun 15
PMID:Specific antigen of murine erythroblasts. 5 10

Numerical and structural chromosome aberrations are frequently found in neoplastic cells. As demonstrated by the new chromosome banding techniques these aberrations are not random, but tend to show a specific occurrence. A model example is the leukemias where many cytogenetical investigations have been done to date. In leukemia chromosome analysis serves the following purposes: to identify a neoplastic process, to confirm and strengthen the hematological diagnosis, for the early diagnosis of transformation from a chronic leukemia into its blastic phase and for following up the clonal evolution of a leukemic cell line. In the discussion of chromosomes and neoplasms it must be mentioned that individuals demonstrating chromosomal instability and some trisomic patients show a greater tendency toward the development of a malignancy. Malignancy is primarily a cellular phenomenon caused by a disturbance in cellular regulation, whose fine events are not known. Therefore the exact role of the chromosomes in neoplastic processes cannot be stated. From experimental investigations it appears that the affected chromosomes carry cell growth regulating factors and also that a specific aberration is the result of the action of a specific agent.
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PMID:Editorial: Chromosomes and human neoplasms. Achievements using new staining techniques. 6 Feb 37

Lymphoid tissues of mice infected with murine leukemia virus (Friend) (MuLV-F) were examined for the presence of cellular markers of MuLV-F infection. The Friend virus-associated cell membrane antigen (FVMA) and the virus group-specific antigen (GSA) were detectable on cells from the spleen and, to a lesser degree, on cells from the bone-marrow. In contrast, neither FVMA nor GSA was found in cells from the thymus. Alterations in the B-cell and T-cell spleen populations of MuLV-F-infected mice were then studied. The proportion of Ig-positive cells declined from the initial 45% (in non-infected controls) to about 10% after 2 weeks of infection. A similar decline of theta-positive cells was noted. However, complement-bearing cells (EAC rosettes) declined even more rapidly and became undetectable in the second week after infection. The treatment of spleen cells from MuLV-F-infected mice with anti-FVMA serum plus complement in vitro reduced the number of detectable Ig-positive cells, specifically, whereas the number of theta-positive cells remained unchanged. Furthermore, B and T cells from spleens of infected mice were separated on an affinity column with anti-Ig antibody-coated beads. The initial cell suspension contained about 45% FVMA-positive cells, about 40% Ig-positive cells and about 40% theta-positive cells. Ig+ cells were retained on the column. The theta-positive cell fraction was collected in the eluate and contained very few FVMA-positive cells with some "null" cells. Most of the FVMA-positive cells were retained on the column, which strongly suggested that they were B cells. These results confirm the previous experiments which showed the selective infections of purified splenic B cells by MuLV-F in cultures.
Int J Cancer 1976 Aug 15
PMID:Interactions of murine leukemia virus (MuLV) with isolated lymphocytes. III. Alterations of splenic B and T cells in Friend virus-infected mice. 6 Feb 87

Three cases of acute myeloid leukaemia developing after treatment of renal disease with cyclophosphamide have been studied. None of the cases was complicated by additional treatment with irradiation or other cytotoxic agents, or by a pre-existing malignancy. Marrow aplasia as a cause of the leukaemia was ruled out. It is suggested that the immunosuppressive action of cyclophosphamide could predispose to the development of malignancy in two ways: malignant clones of cells could emerge and multiply or oncogenic viruses could invade the cells or escape from immunological control and cause induction and development of malignancy.
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PMID:Acute leukaemia after immunosuppressive therapy. 6 43

Polyguanylate- and poly(2'-O-methyl)uridylate-Sepharose have been prepared for affinity chromatography of DNA polymerases of viral origin (reverse transcriptase). Both cellular DNA polymerases and reverse transcriptase bind to polyguanylate-Sepharose. The cellular polymerases can be eluted from the column between 0.32 and 0.42 M NaCl while reverse transcriptase eluted between 0.56 and 0.78 M NaCl. However, only reverse transcriptase adheres to poly(2'-O-methyl)uridylate-Sepharose and can be eluted at approximately 0.35 M NaCl. The columns were used to partially purify RNA-dependent DNA polymerase from spleens of mice infected with Rauscher leukemia virus. The enzyme preparation is about 1300-fold purified and is inhibited by antiserum prepared against purified reverse transcriptase from Rauscher leukemia virus to the same extent as the virion enzyme.
Cancer Biochem Biophys 1976 Aug
PMID:Separation of cellular and viral DNA polymerases by affinity chromatography on polynucleotide-Sepharose. 6 98

Adriamycin inhibited the endogenous RNA-, poly (A)-d(T)12-, and calf thymus DNA-catalyzed reaction of reverse transcriptase from AKR mouse murine leukemia virus (AKR-MLV). This inhibition was found at the reaction levels of endogenous RNA-directed and subsequent DNA-directed DNA synthesis. Although adriamycin and actinomycin D significantly reduced the growth of AKR mouse cells (K3b), the treatment with adriamycin could bot inhibit the AKR-MLV production in these cells. Actinomycin D inhibited AKR-MLV production completely in the same experimental condition. In adriamycin-resistant K3b/Am cells, which were isolated by intermittent treatment of K3b cells with adriamycin, persistence of AKR-MLV was demonstrated. K3b/Am cells showed some altered characteristics such as reduced growth rate and tumorigenicity.
Cancer Res 1976 Sep
PMID:Effects of adriamycin on the reverse transcriptase and the production of murine leukemia virus. 6 7

When cells are infected by C-type viruses such as Moloney sarcoma/leukaemia virus, new antigens appear on the cell membrane. Mice and rats will respond immunologically to the antigen(s). It was uncertain whether the antigens were related to the viral structural proteins or to non-virion, tumour-specific surface antigens (TSSA) or both. In an 125I-antiglobulin binding assay, Moloney virus completely blocked the binding of mouse and rat sera to virus shedding target cells, thus suggesting that mice and rats recognise only viral proteins. Mice responded to type-specific and rats mainly to group-specific determinants on the virus. Individual Moloney viral proteins were prepared using the guanidine HCl method and were used to block the binding of the rat anti-Moloney immune serum to Moloney virus shedding target cells. By this method, it was demonstrated that the rat serum contains specificities for the viral proteins gp70 and p30, but it was not possible to detect any antibodies directed towards non-virion or TSSA-like molecules.
Int J Cancer 1976 Oct 15
PMID:Specificity of serum from rodents immune to Moloney C-type virus-induced tumours. 6 44


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