Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Gardner-Rasheed strain of feline sarcoma virus (GR-FeSV), is a recent isolate of a naturally occurring cat sarcoma. The primary translational product of GR-FeSV (GR P70) was shown to be a phosphoprotein with associated tyrosine-specific protein kinase activity. The relationship between the GR-FeSV provirus and once genes of other transforming retroviruses known to code for tyrosine kinases was examined by molecular hybridization. Probes repesenting onc genes of Snyder-Theilen and McDonough strains of feline sarcoma virus, Rous sarcoma virus, and Abelson murine leukemia virus did not detectably hybridize integrated GR-FeSV. These findings suggest that GR-FeSV contains a distinct tyrosine kinase-coding onc gene.
 ...
PMID:Analysis of the primary translational product and integrated DNA of a new feline sarcoma virus, GR-FeSV. 660 28

Examination of syngeneic tumor regressor sera prepared by immunization of mice with several different lymphomas revealed a common pattern of reactivity to proteins expressed in these tumors. Antibodies present in these sera immunoprecipitate a triplet of proteins of 115,000 mol wt (p115), 80,000 mol wt (p80), and 32,000 mol wt (p32) from many but not all T cell lymphomas of mice. P80, the predominant molecular species immunoprecipitated with these sera, is a nonglycosylated, phosphoprotein that does not appear to be expressed at the cell surface. Comparison of the tryptic peptides of p32 and p80 indicated that the peptides found in p32 are a subset of those found in p80. Comparison of the tryptic peptides of p80 with those of the p120 gag-fusion protein of Abelson murine leukemia virus demonstrated that p80 and p120 did not share tryptic peptides. Comparison of the partial proteolytic products generated by treatment of p80 molecules from different tumors with V8 protease did not reveal heterogeneity in p80 among tumors of different strains of mice. Direct labeling and competition blocking experiments with lysates from normal cells failed to provide evidence of p80 synthesis in normal thymus, spleen, or bone marrow. Thus, p80 is a biochemically identified tumor-related antigen of mouse lymphomas.
 ...
PMID:P80: a tumor-related protein found in many lymphomas of mice. 698 62

The putative transforming proteins of the four acute leukaemia viruses belonging to the MC29 subgroup were shown to be phosphorylated in vivo. Comparison of the MC29 and CM11 encoded phosphoproteins revealed identical tryptic phosphopeptide maps, with both the gag and myc domains being phosphorylated. In contrast, the MH2 phosphoprotein was only phosphorylated on the gag domain. Analysis of partial transformation-defective MC29 deletion mutants revealed that the deletions had removed the v-myc specific phosphopeptides. Phosphoamino acid analysis showed that these deleted phosphopeptides were phosphorylated on threonine. Moreover, a back mutant that had regained transforming ability had regained these phosphopeptides. These studies correlate the phosphorylation of the gag-myc protein with the transformation capability of the virus.
 ...
PMID:Phosphorylation of specific sites in the gag-myc polyproteins encoded by MC29-type viruses correlates with their transforming ability. 698 57

The complete amino acid sequence of the group-specific antigen gene-encoded RNA binding phosphoprotein p12 has been determined for both Rauscher and Moloney leukemia viruses. Large fragments generated by acid, and cyanogen bromide and hydroxylamine cleavage, and Staphylococcus aureus V8 protease digestion were subjected to automated sequencing. Both Rauscher and Moloney p12 are composed of 84 amino acids arranged in alternating variable and conserved regions. The homology between the conserved internal and COOH-terminal regions is greater than 95%, but the NH2-terminal and internal variable regions show 59 and 51% homology, respectively. The role of such regions in the type-specific biological activities of these molecules is discussed.
 ...
PMID:Complete amino acid sequence of the group-specific antigen gene-encoded phosphorylated proteins of mouse leukemia viruses. 703 75

CD34 is expressed on human hematopoietic stem and progenitor cells, and its clinical usefulness for the purification of stem cells has been well established. However, a similar pattern of expression for murine CD34 (mCD34) has not yet been determined. Two polyclonal anti-mCD34 antibodies that specifically recognize both endogenous and recombinant murine CD34 were developed to characterize the mCD34 protein and to determine its pattern of expression on murine cell lines and hematopoietic progenitor cells. Fluorescence-activated cell sorter analysis showed that mCD34 is expressed on NIH/3T3 embryonic fibroblasts, PA6 stromal cells, embryonic stem cells, M1 leukemia cells, and a subpopulation of normal bone marrow cells. Murine CD34 was found to be a glycoprotein expressed on the cell surface as either a full-length (approximately 100 kD) or truncated (approximately 90 kD) protein in NIH/3T3 and PA6 cells. Recombinant full-length CD34, when expressed in the CHO-K1 cell line, had a molecular weight of approximately 105 kD. Full-length CD34 expressed on M1 leukemia cells, had a higher apparent molecular weight (110 kD). These results suggest that there are glycosylation differences between CD34 expressed by different cell types. The full-length form, but not the truncated form, is a phosphoprotein that is hyperphosphorylated in response to 12-0-Tetradecanoyl phorbol 13-acetate treatment, suggesting potential functional differences between the two forms. Selection of the 3% highest-expressing CD34+ bone marrow cells enriched for the hematopoietic precursors that form colony-forming unit-spleen (CFU-S), CFU-granulocyte-macrophage, and burst-forming unit-erythroid. Transplantation of lethally irradiated mice with these cells demonstrated both short- and long-term repopulating ability, indicating that this population contains both functional hematopoietic progenitors and the putative stem cell. These antibodies should be useful to select for murine hematopoietic stem cells.
 ...
PMID:Characterization of murine CD34, a marker for hematopoietic progenitor and stem cells. 751 70

The role of the lyn product (p53/p56lyn), a membrane-associated protein tyrosine kinase in the signaling pathway used by granulocyte macrophage-CSFR (GM-CSFR) was investigated by using the GM-CSF-dependent human megakaryoblastic leukemia cell line M-07e. M-07e cells express GM-CSFR and are dependent on GM-CSF for survival and proliferation in vitro. Treatment with anti-lyn Abs coimmunoprecipitated, along with lyn product, the beta subunit of GM-CSFR and a phosphoprotein with a molecular mass of 120 kDa (p120) in the lysates of M-07e cells but not in the lysates of human monocyte-derived macrophages (HMDM) or human lymphoid leukemia cells. That the 120-kDa phosphoprotein coimmunoprecipitated by anti-lyn Abs is the beta subunit of GM-CSFR was confirmed in the immunoprecipitates (IP) of M-07e cells with the use of an agarose-conjugated anti-p-tyr mAb. The formation of GM-CSF/GM-CSFR/lyn signaling complexes was verified in an autoradiographic study with anti-lyn IP of M-07e cells that had been bound with 125I-labeled recombinant human (rh)GM-CSF. The p120 protein (beta subunit) was not detected in the IP of M-07e cells with anti-fyn or anti-PI3 Abs. A direct association of Lyn kinase with the beta subunit of GM-CSFR was illustrated with a reversed approach showing the recovery of Lyn protein in anti-beta (CRS1) but not anti-alpha IP of M-07e cells that had been starved for a prolonged period. Finally, the interaction of Lyn kinase with the GM-CSFR complexes was further corroborated using anti-GM-CSF (G133) mAb, which coimmunoprecipitated both the p120 beta subunit and lyn product in the lysates of M-07e cells that had been bound with rhGM-CSF before cell lysis. Removal of rhGM-CSF from culture medium for 10 to 12 h resulted in a marked decrease in lyn-associated kinase activity but not the beta subunit/lyn kinase complex formation. Taken together, our results showed that, in M-07e cells, Lyn protein tyrosine kinase (p53/p56lyn) is stably associated with a constitutively phosphorylated beta subunit of the GM-CSFR in a manner that seems to be independent of lyn kinase activity.
 ...
PMID:Association between Lyn protein tyrosine kinase (p53/56lyn) and the beta subunit of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors in a GM-CSF-dependent human megakaryocytic leukemia cell line (M-07e). 763 65

A basic helix-loop-helix phosphoprotein gene, G0S8, was recently isolated by differential screening of cDNA from human blood mononuclear cells stimulated with a T cell mitogen and cycloheximide. In this study, G0S8 expression was examined in normal and malignant hematopoietic cells by Northern blot analysis and reverse transcription-polymerase chain reaction (RT-PCR). G0S8 expression was observed in most fresh samples of acute myelogenous leukemia (AML) (28/30) and most cases of adult acute lymphoblastic leukemia (ALL) (9/11) regardless of clinical classification. G0S8 mRNA was also detected in all cases tested of chronic myelogenous leukemia (CML) in blast crisis. However, G0S8 expression was not detected in CML patients in chronic phase, nor in normal bone marrow or other hematopoietic cells. G0S8 has been mapped using fluorescence in situ hybridization (FISH) to human chromosome 1q31, the same site reported for the B cell homolog BL34/1R20 and within a region implicated in the development of hematological malignancies. The consistent observation of G0S8 mRNA in patient samples of acute leukemia suggests that G0S8 expression may either play a role in leukemogenesis or represent a common consequence of dysregulated growth.
Leukemia 1995 Aug
PMID:Differential expression of a basic helix-loop-helix phosphoprotein gene, G0S8, in acute leukemia and localization to human chromosome 1q31. 764 15

The c-src proto-oncogene encodes a M(r) 60,000 phosphoprotein, pp60c-src, with tyrosine-specific protein kinase activity. We have used an immune complex protein kinase assay for pp60c-src to analyze a spectrum of B-cell neoplasms. pp60c-src activity was elevated in all five hairy cell leukemia specimens and in a number of the large cell and immunoblastic lymphomas; neoplasms representing later stages in B-cell development. pp60c-src activity was low in neoplastic cells which correspond to early and intermediate stages in B-cell development (acute and chronic lymphatic leukemia, lymphoblastic lymphoma, small lymphocytic lymphoma). The enhanced pp60c-src activity was associated with high levels of pp60c-src protein. However, increased expression of c-src was not associated with amplification or gross structural rearrangement of the c-src gene. This preliminary study demonstrates elevated levels of pp60c-src protein and tyrosine protein kinase activity in neoplasms corresponding to the later stages of B-cell ontogeny.
Leukemia 1993 Sep
PMID:Increased expression of the src proto-oncogene in hairy cell leukemia and a subgroup of B-cell lymphomas. 769 Apr 41

The UCRBP (YY1, delta, NF-E1) protein has been isolated for its ability to bind to the UCR (upstream conserved region) site present in the conserved murine leukemia virus long terminal repeat. UCRBP carries a highly charged N-terminal domain and four C2-H2-type zinc fingers at its C-terminal end. The present study reveals the following results: (i) The UCR site is present in the upstream and/or regulatory regions of numerous mammalian cellular and viral genes to which both recombinant and cellular UCRBP bind. UCR sites are also found in the regulatory regions of repetitive sequences including human LINE-1 elements and mouse intracisternal-A particle sequences. (ii) By immunological and UV cross-linking experiments, we found that two proteins, of approx. 68 kDa and an antigenically related protein of approx. 40 kDa, account for much of the UCR-binding activity in T-lymphocytes. (iii) There is evidence that UCRBP acts as a phosphoprotein. Eight consensus phosphorylation sites are found in the deduced amino-acid sequence of human UCRBP. The cellular UCR-binding activity was abolished by phosphatase treatment, and there is an incremental increase in apparent molecular mass between the cytoplasmic and nuclear forms of the protein, suggesting phosphorylation. (iv) Although UCRBP has been previously shown to act as a transcriptional repressor, we show here that UCRBP can also act as a positive transactivator of a reporter driven by UCR elements when used in co-transfection assays. This transactivation occurred in a dose-restricted manner and was absent at high concentrations of a UCRBP expression plasmid, indicating a complex mode of function.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Characterization of hUCRBP (YY1, NF-E1, delta): a transcription factor that binds the regulatory regions of many viral and cellular genes. 782 90

Leukemias induced with the v-abl or BCR/ABL oncogene undergo a process of tumor progression which suggests that the ABL oncogene is required but not sufficient for full transformation. In order to identify cellular changes that correlate with progression to full transformation in v-abl transformed lymphoblasts Abelson virus (A-MuLV)-infected murine bone marrow was plated over a pre-established stromal feeder layer. Shortly after A-MuLV infection, transformed lymphoblasts were poorly oncogenic, but over time, progressed in a stepwide manner to a more oncogenic state. The transformants first acquired the ability to grow efficiently in agar, but only over the feeder layer. They next progressed to efficient feeder-independent growth in liquid culture, and then to efficient feeder-independent growth in soft agar. Cell lines that reached the advanced stage of feeder-independent agar growth showed increased detection by antiphosphotyrosine Western blot of the GAP-associated p62 phosphoprotein as well as of a 55 kDa phosphoprotein while detection of the P160 v-abl phosphoprotein remained constant throughout all stages of progression. Although the identity of the p55 phosphoprotein and the mechanism by which detection of p55 and p62 phosphoproteins change on the Western blots during tumor progression are unknown, the data demonstrate that these changes strongly correlate with the stage of progression of v-abl-transformed cells and raise the possibility that these changes may play a role in tumor progression in this model.
Leukemia 1995 Jan
PMID:Increased detection of specific tyrosine phosphoproteins correlates with tumor progression of Abelson virus-infected lymphocytes. 784 13


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>