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)

Ribonucleotide reductase consists of two non-identical protein subunits that are required for enzyme activity. These subunits are encoded by different genes and are not expressed coordinately as the cells pass through the cell cycle. Using specific cDNAs for the non-heme iron (NHI) and the effector-binding (EB) subunits the levels of the mRNAs for these two subunits were determined in leukemia L1210 cells during the transition from the G0/G1 phase to the S and G2/M phases of the cell cycle. Synchronized populations of L1210 cells were obtained either by ethylene glycol-bis(beta-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA) treatment or by enrichment by elutriation centrifugation. The changes in the levels of the mRNAs for NHI and EB subunits were compared with the changes in the levels of the mRNAs for actin, p53, c-myc, thymidine incorporation into DNA, and DNA content by flow cytometric measurements. Synchronization of the cells by the two methods resulted in quantitative differences in the responses. The EGTA synchronized L1210 cells showed maximal increases of 9.3- and 5.7-fold in the mRNAs for the NHI and EB subunits, respectively. The peak level of the NHI mRNA was observed at 12 hr after the addition of calcium ions. The peak increase in the level of the mRNA for the EB subunit was observed between 12 and 15 hr after the addition of calcium ions. The rate of increase for the mRNA for c-myc was greater than the increase in the mRNA for the NHI subunit.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Changes in messenger RNA levels for the subunits of ribonucleotide reductase during the cell cycle of leukemia L1210 cells. 270 Sep 14

The Friend virus-transformed erythroleukemic cell line DP16-9B4 has undergone a complex rearrangement of the p53 oncogene and lacks any detectable expression of the p53 protein. We report here characterization of both p53 alleles in this cell line and identify independent integrations of Friend murine leukemia virus sequences into the coding region of both alleles.
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PMID:Integration of Friend murine leukemia virus into both alleles of the p53 oncogene in an erythroleukemic cell line. 284 84

A common site of ecotropic murine leukemia virus integration designated Evi-2 (ecotropic viral integration site-2) has been identified in BXH-2 myeloid tumors. As part of experiments to determine whether Evi-2 identified a new proto-oncogene locus involved in myeloid disease, we determined its chromosomal location. We mapped Evi-2 to mouse Chromosome 11 using standard recombinant inbred strain and genetic backcross analysis. We then determined the location of Evi-2 relative to other proto-oncogene and growth factor loci located on Chromosome 11 by interspecific backcross analysis. The loci included in this study were the proto-oncogene loci, Erbb, Erba, and Rel, as well as, Il-3 (interleukin-3), Csfgm (granulocyte-macrophage colony stimulating factor), and Trp53-1 (transforming protein p53). All loci except Erbb had been previously mapped to Chromosome 11 with the use of somatic cell hybrids and consequently their positions on Chromosome 11 were not known. One proto-oncogene, Erbb-2 (analogous to the neu proto-oncogene), and one growth factor locus, Csfg (granulocyte colony-stimulating factor), which had not been mapped in the mouse were also localized on Chromosome 11 using the interspecific backcross mice. Recombination between Evi-2 and all proto-oncogene and growth factor loci was demonstrated, suggesting that Evi-2 may ultimately identify a new proto-oncogene involved in myeloid disease. This study revealed a number of interesting conserved linkage groups common to mouse and man.
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PMID:Localization of Evi-2 to chromosome 11: linkage to other proto-oncogene and growth factor loci using interspecific backcross mice. 285 Nov 24

Sera and cerebrospinal fluid (CSF) from patients with human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy (HAM) were analyzed by Western blotting, and normal human leukocytes were transformed by co-cultivation with HAM patients' leukocytes. The sera and CSF from all HAM patients formed specific bands with HTLV-1 viral proteins, including p19, p24, p28, p32, p40 and p53. After 2-3 weeks of co-cultivation, scattered foci of cell aggregates were noted on macrophage sheets. Surface markers of the transformed cells were OKT3(+), OKT4(+), OKT8(-), IL-2 receptor(+) and EBNA(-). Chromosome analysis showed a normal karyotype. HTLV-1 viral genome was integrated into DNA isolated from transformed cell lines. Electron microscopy revealed type C virus particles in transformed T-cell lines. These results indicate that peripheral leukocytes from HAM patients can transform HTLV-1-negative leukocytes and HAM patients have the potential to acquire adult T-cell leukemia in the future.
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PMID:Transformation of human leukocytes by co-cultivation with HTLV-1-associated myelopathy patients' leukocytes. 288 13

Southern blot analysis of various genes was used to compare the human promyelocytic leukemia cell line HL-60 and the BII cell line, which reportedly arose as a spontaneous differentiation inducer-resistant variant from an HL-60 culture. Granulocyte-macrophage colony stimulating factor gene restriction fragment polymorphism, due to a partial deletion of one of the alleles of this gene in HL-60, was not observed in the BII cells. Furthermore, the p53 oncogene, most of which is deleted in the HL-60 cell line, was found to be intact in the BII cell line. Human leukocyte antigen typing revealed that the two cell lines shared the A locus but differed at the B locus. Several unique restriction fragments hybridizing to human leukocyte antigen class I and DR beta gene probes were observed in the DNA digests of each cell line. Altogether these data provide definitive evidence that BII represents a human cell line of different origin than HL-60. Further lineage determination of this cell line could add a useful member to the group of leukemic cell lines.
Leukemia 1987 Feb
PMID:Southern blot analysis of BII cell line--a putative variant of HL-60. 288 53

A comparative study on the expression of nuclear and cytoplasmic oncogenes was carried out using the Northern blotting technique, in Rauscher virus induced primary leukemias and the more malignant transformed cell lines derived from them. The latter grow permanently in vitro. Hyperplastic spleens obtained from mice recovering from anemia were analysed as controls. In addition to the detection of mRNAs, Southern blotting was carried out to observe whether rearrangement or amplification of oncogenes had occurred. The results show that the nuclear oncogenes c-myc, c-myb and p53 are strongly expressed in leukemic tissue, whereas c-fos transcripts show a much weaker hybridization. The expression of two of these oncogenes, c-myc and c-myb was followed during differentiation in myeloid leukemic cells and showed a gradual decrease when compared with the actin gene, which is constitutively transcribed. A large number of cytoplasmic oncogenes is expressed in the leukemic cells lines, i.e. c-abl, c-fms, c-fes, c-src, c-ros, c-H-ras, c-K-ras and N-ras. Of these, transcripts coding for c-abl and c-src were absent in blast cells of acute erythroid leukemias. Transcripts coding for c-erb, c-mos and c-sis could also not be detected. A number of putative oncogenes which are reported to play a role in Moloney and Friend virus induced leukemias for instance pim-1, fis-1, fim-1 and fim-2 were also used for screening. Only expression of pim-1 in Rauscher virus induced myeloid leukemic cells and in primary acute erythroid leukemias could be observed. At the DNA level no rearrangement or amplification of any of the oncogenes investigated could be detected. The results show that a number of oncogenes are expressed simultaneously in the same leukemic tissue or cell lines. It therefore seems likely that the presence of transcripts of different oncogenes is associated with the progression of leukemia, but is not the primary cause of leukemogenesis or of the transformation of these cells into established cell lines.
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PMID:Oncogene expression in Rauscher murine leukemia virus induced erythroid, myeloid and lymphoid cell lines. 291 75

Three distinct monoclonal antibodies (MAbs) specific for human T-cell leukemia virus type-I (HTLV-I) core proteins with molecular weights of 24 kDa (p24), p19 or p15 were produced, characterized and compared. These antibodies were named NOR-1 (anti-p24, IgG2a), GIN-7 (anti-p19, IgG2b) and FR-45 (anti-p15, IgG2a). Immunofluorescence assay showed that they reacted specifically with methanol-fixed cells of virus-bearing cell lines, and that only GIN-7 bound, albeit weakly, to the surface of a small percentage of viable cells. Like natural antibodies to HTLV-I in human serum, GIN-7 stained the fixed cells brightly and diffusely, and gave more intense fluorescence than NOR-1 and FR-45, which stained restricted areas of the cells. NOR-1, GIN-7 and FR-45 specifically precipitated core proteins p24, p19 and p15, respectively, from a lysate of HTLV-IMT-2 labelled with 35S-cysteine. NOR-1 precipitated p53, p36, and p24, GIN-7 precipitated p53, p32, p28 and p19, and FR-45 precipitated p53, p36, and p15 from a lysate of 35S-cysteine-labelled MT-2 cells. GIN-7 also precipitated p32, p28 and p19 from a lysate of MT-2 cells, labelled by surface iodination, but NOR-1 and FR-45 did not detect any proteins in this lysate. GIN-7 also detected p28 in 3H-glucosamine-labelled MT-2 cells. Antibody binding competition assay showed that the sera of ATL patients significantly interfered with the binding of NOR-1 and GIN-7 but not with that of FR-45, to antigens of disrupted virus of MT-2 cells. This complete set of MAbs against the HTLV-I gag gene products is useful for biological and functional studies of the HTLV-I core proteins.
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PMID:Antigens related to three core proteins of HTLV-I (p24, p19 and p15) and their intracellular localizations, as defined by monoclonal antibodies. 300 Sep 53

We examined synthesis of the cellular phosphoprotein p53 in fresh bone marrow or peripheral blood cells from normal donors and from patients with leukemia, preleukemia, or other hematopoietic disorders. Lysates of cells labeled with [35S]methionine were immunoprecipitated with monoclonal antibodies to p53, and the immunoprecipitates were analyzed by NaDodSO4/polyacrylamide gel electrophoresis and autoradiography. Bone marrow or peripheral blood cells from 8 of 33 patients with hematopoietic disorders showed increased p53, seven of the eight occurring in cells of patients with preleukemia or acute myelogenous leukemia. Increased p53 synthesis was not associated with p53 gene amplification, as shown by Southern blot analysis. Synthesis of p53 was not increased in any of nine normal human bone marrow samples or eight normal human peripheral blood granulocyte, macrophage, and lymphocyte samples. The hematopoietic cells of patients in remission or with chronic forms of leukemia did not generally synthesize elevated levels of p53. In addition, we found negligible p53 mRNA and protein expression in a variety of human myeloid leukemia lines blocked at different stages of differentiation. Southern blot analysis showed that, except for the HL-60 cells, the p53 gene of the myeloid cell lines was intact. In view of recent evidence implicating p53 in transformation of cultured cells, our results using fresh leukemia cells suggest that p53 may contribute to the phenotype of certain leukemias in vivo.
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PMID:Increased expression of p53 protein in human leukemia cells. 301 45

The erythroleukemia induced by the Friend spleen focus-forming virus (SFFV) in mice exemplifies a multistep oncogenic process. Its sequential steps include a rapid polyclonal hyperplastic stage and a more slowly developing malignant stage characterized by autonomous erythroid cells. We report here that the helper virus normally present in mice infected by SFFV is not required for development of the second stage of transformation. In this study, mice were infected with a polycythemia-inducing variant of SFFV which was prepared as a helper-free stock (L. Wolff and S. Ruscetti, 1985, Science 228, 1549). Highly malignant cells could be detected in helper-free SFFV-infected mice by their transplantability into the omentum of sublethally irradiated mice, and erythroleukemia cell lines, typical of previously isolated Friend murine erythroleukemia cell lines, could be established from diseased spleens. Like their helper virus-containing counterparts, the lines established with helper-free SFFV are inducible for hemoglobin synthesis with a variety of chemicals, but not erythropoietin, and express p53, a marker of malignant transformation. Although the cells expressed SFFV encoded proteins, none expressed gene products of replication competent murine leukemia viruses.
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PMID:Induction of the autonomous stage of transformation in erythroid cells infected with SFFV: helper virus is not required. 301 73

Expression of the gene encoding the nuclear phosphoprotein p53 (a proto-oncogene classified in the same functional family as c-myc and E1a adenovirus gene) was examined in a human T-cell leukemia (KE-37R cell line). No p53 (or a modified product) could be detected by immunoprecipitation with monoclonal antibodies P Ab 421 and P Ab 122 in KE-37R cell extracts, and no p53-specific RNA was characterized by Northern blot analysis. Southern blot using a murine p53 cDNA clone as a probe, did not reveal any gross rearrangement in the structure of the gene. However, this molecular probe was not suited for investigating the 5' end of the gene which contains the promoter and the non coding exon 1. It is interesting to notice that in KE-37R cells, c-myc has been activated by a t(8; 14) (q24; q11) translocation, suggesting that the c-myc product might substitute to some functions normally requiring p53.
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PMID:[Lack of expression of the protein p53 gene in a human T-cell leukemia line]. 312 85


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