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)

Apoptosis or programmed cell death is observed in a variety of organisms and tissues and is characterized by distinct morphologic changes to the cell. Although early indicators of this process have been described, their functional relevance remains unknown. We have used two-dimensional gel electrophoresis to look for characteristic and consistent changes in the phosphorylation state of proteins during apoptosis, induced by different agents, in the B cell lymphoma line, BM13674, and the T cell leukemia line, CEM-C7. We report that apoptosis induced by either heat treatment or by ionizing radiation exposure is accompanied by dephosphorylation of a limited number of specific proteins. The pattern of dephosphorylation was similar after both treatments in BM13674 cells. In CEM-C7 cells, dephosphorylation was also observed after heat and irradiation. One of these proteins corresponded to one dephosphorylated in BM13674 cells. Okadaic acid, an inhibitor of phosphatases 1, 2A, and, to a lesser extent, 2B, prevented apoptosis in all cases and inhibited dephosphorylation of this common protein as well as some of the others. It seems likely that activation of a phosphatase(s) or loss of activity of a kinase is of central importance in apoptosis in these systems.
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PMID:Specific protein dephosphorylation in apoptosis induced by ionizing radiation and heat shock in human lymphoid tumor lines. 154 32

The BCL-2 (B-cell lymphoma/leukemia-2) gene is frequently involved in t(14;18) translocations in non-Hodgkin's lymphomas and encodes a 26-kDa intracellular, membrane-associated protein. Expression of the BCL-2 gene has previously been correlated with cellular proliferation in normal and neoplastic lymphoid cells under a variety of experimental conditions. To examine the regulation of p26-BCL-2 protein levels during the cell cycle, we utilized the method of counterflow centrifugal elutriation to enrich for cells in various phases of the cell cycle. Relative levels of p26-BCL-2 protein were measured by immunoblotting, and comparisons were made with a cell cycle-regulated protein, p62-CYCLIN-A, and a protein whose levels are constant throughout the cell cycle, p36-PCNA (DNA polymerase-delta auxiliary factor). Relative levels of p26-BCL-2 and p36-PCNA did not vary among cell fractions enriched for specific phases of the cell cycle, whereas p62-CYCLIN-A was elevated in late S- and G2/M-phase cells. Similar results were obtained with lymphoma and leukemia cell lines that have either normal or translocated BCL-2 genes. These results obtained by elutriation were confirmed by pharmacologically inducing cell cycle arrest in proliferating lymphoid cell lines with hydroxyurea, quercetin, and nocodazole which blocked cells at S, G2, and M phases, respectively. Taken together, the data indicate that p26-BCL-2 is not a true cell cycle-regulated protein, although its levels can fluctuate in connection with changes in rates of cellular proliferation under some circumstances.
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PMID:Cell cycle analysis of p26-BCL-2 protein levels in proliferating lymphoma and leukemia cell lines. 158 93

The use of bone marrow transplantation is increasing in the management of advanced cancers. In autologous bone marrow transplantation (ABMT), many investigators have attempted to purge the graft of residual tumor cells because of concern that reinfused tumor cells might contribute to relapse. The feasibility of various methods (exposure to chemical agents, monoclonal antibodies (MoAbs), toxins, dye, magnetic microparticles ... ) has been confirmed. In allogeneic bone marrow transplantation, clinical studies have related the prevention of graft-versus-host disease reaction through the partial depletion of T lymphocytes in the donor graft limited to 1 log to maintain a graft-versus-leukemia (GVL) effect. Similarly, the feasibility of different assays (soybean agglutinin, Moabs and magnetic microparticles) have been shown. However, the clinical benefit of BM purging remains to be demonstrated. For ABMT, only recent data on B-cell lymphoma and leukemia strongly support the clinical usefulness of an ex-vivo purging. For allogeneic BMT, one question remains controversial: is T lymphocytes depletion the best method for GVHD prevention?
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PMID:[Ex-vivo treatment of a bone marrow graft]. 160 93

Clinical data have suggested that graft-versus-host disease (GVHD) plays a crucial role in the antileukemic effects of bone marrow grafts. We investigated (a) whether bone marrow cells unable to induce GVHD can effect graft-versus-leukemia (GVL) activity and (b) whether such antileukemic capacity depends on the presence of T lymphocytes in the graft. Balb/c mice were inoculated with A20 cells, a B-cell lymphoma/leukemia of Balb/c origin. Four weeks after tumor inoculation the animals were lethally irradiated and received a bone marrow graft. Cells from (Balb/c x C57) F1 or (C3H x Balb/c) F1 hybrids were transplanted into parental-strain Balb/c mice. Since lymphocytes from F1 hybrids are unable to cause graft-versus-host reactivity against a parental-strain animal, we used this experimental setting to explore GVL effects in a GVHD-free system. In vitro incubation with monoclonal anti-Thy-1.2 antibody plus complement was used to eliminate Thy-1+ cells. After syngeneic transplantation, the death rate due to leukemia remained unchanged (91%) compared with that among untreated animals (86%). Following transplantation of F1 marrow cells of either (C57 x Balb/c) F1 or (C3H x Balb/c) F1 origin, death rates of 40% and 50% were observed; these were significantly lower. Depletion of Thy 1+ cells from bone marrow graft caused only a slight increase in the leukemic death rate after transplantation of bone marrow of (C57 x Balb/c) F1 hybrid origin (50%), but a high leukemic death rate was seen after transplantation of (C3H x Balb/c) F1 bone marrow (100%). Additional experiments with fully allogeneic, T-cell-depleted C57 bone marrow transplantation suggest an antileukemic effect that is comparable to that seen after transplantation of unmanipulated F1 bone marrow. Taken together, our results indicate that GVL activity can be dissociated from graft-versus-host reaction.
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PMID:Graft-versus-leukemia activity after bone marrow transplantation does not require graft-versus-host disease. 163 77

A Japanese patient with adult T-cell leukemia-lymphoma (ATL) showed a disease progression from the smoldering type to the chronic type and finally to the acute type. The patient was variously treated, including 2'-deoxycoformycin, with some beneficial effects. During the chronic type he developed a composite lymphoma consisting of T-cell lymphoma (ATL) of medium-sized cells and B-cell lymphoma of diffuse large cell type. At that time, he also suffered from miliary tuberculosis and adenovirus type 11-induced hemorrhagic cystitis, indicating that he was in a marked immunodeficient state. Southern-blot analysis revealed that the two malignancies have distinct clonal origin on the basis of the following results: (1) clonally rearranged T-cell receptor beta-chain gene (TcR-beta gene) and germline configuration of immunoglobulin heavy chain gene (IgH gene) in ATL leukemic cells, (2) clonal rearrangement of IgH gene in lymphoma cells, indicating a monoclonal B-cell lymphoma, (3) monoclonal integration of HTLV-I provirus in ATL leukemic cells, (4) definite presence and monoclonal origin of EBV genome in lymphoma cells. This is the first report of secondary EBV genome carrying monoclonal B-cell lymphoma in an ATL patient. It is suggested that the immunodeficient state in the patient with ATL allows the emergence of EBV-related B-cell lymphoma.
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PMID:Epstein-Barr virus (EBV) genome carrying monoclonal B-cell lymphoma in a patient with adult T-cell leukemia-lymphoma. 165 51

A gene-transfer approach was used to explore the function of the BCL2 (B-cell lymphoma/leukemia 2) gene in a human T-cell line, Jurkat. Though stable introduction of a BCL2 expression plasmid into Jurkat T cells was by itself insufficient, the combined transfer of BCL2 and MYC genes markedly enhanced the tumorigenicity of these cells in athymic mice. Moreover, a BCL2 antisense expression plasmid ablated tumor formation by Jurkat cells, providing further evidence that this oncogene contributes to the regulation of the in vivo growth of these human T lymphocytes. In addition to their influence on tumor formation, BCL2 sense and antisense expression plasmids increased and decreased, respectively, the in vitro survival of Jurkat T cells in serum-free medium. These observations extend to T cells the finding of synergy of BCL2 with MYC previously reported for B cells and provide evidence that BCL2 can regulate the growth of human T cells.
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PMID:BCL2-mediated tumorigenicity of a human T-lymphoid cell line: synergy with MYC and inhibition by BCL2 antisense. 169 20

A pathogenetic relationship is postulated for the development of membranoproliferative glomerulonephritis type I in non-Hodgkin's lymphoma (B-cell lymphoma of low-grade malignancy) and myeloproliferative syndrome, which we have observed in eight patients. This hypothesis is supported by the fact that chronic lymphatic leukaemia and immunocytoma are often associated with immunodysregulative phenomena, and by the immunohistological and ultrastructural findings in the kidney, especially the frequent electron-microscopic finding of cryoglobulins, which results in the membranoproliferative type of immune-complex glomerulonephritis, an expression of a disturbance in immune balance. The pathogenetic mechanism may involve cryoglobulins themselves as immune complexes; it is also possible that monoclonal cryoglobulins combine with an antigen to form immune complexes or lead to in situ formation of immune complexes. In addition, other immune complexes, for example with endogenous tumour-associated antigens and exogenous antigens (e.g. hepatitis antigens), may be involved in the pathogenesis.
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PMID:[Membranoproliferative glomerulonephritis in non-Hodgkin's lymphoma nad myeloproliferative syndrome--a causal relationship?]. 172 39

Three predominantly CD8+ CTL lines, TIL 501, TIL 620, and TIL 660, were generated from three HLA-A2+ melanoma patients by culturing tumor-infiltrating lymphocytes in 1000 U/ml IL-2. These tumor-infiltrating lymphocytes lysed 12 of 18 HLA-A2+ autologous and allogeneic melanomas, but none of 20 HLA-A2-negative melanomas. They also did not lyse the MHC class I negative lymphoma-leukemia cell lines, Daudi, K562, or HLA-A2+ non-melanoma cell lines including PHA or Con A-induced lymphoblast, fibroblast, EBV-transformed B cell, Burkitt's B cell lymphoma, and colon cancer cell lines. Autologous and allogeneic melanoma lysis was inhibited by anti-CD3, by anti-MHC class I, and by anti-HLA-A2 mAb, indicating recognition of shared tumor Ag among melanoma cell lines in a TCR-dependent, HLA-A2-restricted manner. Six HLA-A2-negative melanoma cell lines obtained from five HLA-A2-negative patients were co-transfected with the HLA-A2.1 gene and pSV2neo. All 17 cloned transfectants expressing cell surface HLA-A2 molecules, but none of 12 transfectants lacking HLA-A2 expression, were lysed by these three HLA-A2-restricted, melanoma-specific CTL. Lysis of the HLA-A2+ transfectants was inhibited by anti-CD3, by anti-MHC class I, and by anti-HLA-A2 mAb, indicating recognition of shared tumor Ag on transfectants in a TCR-dependent, HLA-A2-restricted manner. These results identify the HLA-A2.1 molecule as an Ag-presenting molecule for melanoma Ag. They also suggest that common melanoma Ag are expressed among melanoma patients regardless of HLA type. These findings have implications for the development of melanoma vaccines that would induce antitumor T cell responses.
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PMID:Shared human melanoma antigens. Recognition by tumor-infiltrating lymphocytes in HLA-A2.1-transfected melanomas. 172 79

We previously demonstrated that the breakpoint of t(11;14)(q23;q32) in the RC-K8 B cell lymphoma cell line lies between CD3 and THY1/ETS1 on chromosome 11q23, and we cloned this region and named it the rck locus. Pulsed-field gel electrophoresis showed that the rck probe B (distal to the breakpoint) and the porphobilinogen deaminase (PBGD) probe detect the same germ line band and also the same rearranged band when DNA from RC-K8 cells was digested with NotI enzyme. Furthermore, Southern blot analysis with somatic cell hybrids showed that the PBGD gene moved to the 14q+chromosome, which confirmed PBGD to be more distal to the centromere than the rck locus. These data allowed us to construct the following order of genes: 11 cen-q23-CD3-rck-PBGD-THY1/ETS1. In this study, three infantile leukemia cell lines with t(11;19)(q23;p13) translocation were also analyzed by pulsed-field gel electrophoresis. CD3D probe detected the rearranged bands in DNA from two of them after digestion with NotI and SacII enzymes, demonstrating that the breakpoints of both cell lines were estimated to be within 360 kilobases of CD3D.
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PMID:Rearrangements on chromosome 11q23 in hematopoietic tumor-associated t(11;14) and t(11;19) translocations. 174 46

Various samples from lymphoproliferative diseases in the skin were analyzed by Southern blotting technique with probes from the T cell receptor gene, immunoglobulin genes, and human T cell leukemia virus-I genome. Samples were taken from 10 mycosis fungoides (MF) patients, 1 parapsoriasis en plaque patient, 10 Adult T cell leukemia/lymphoma (ATL) patients, 1 cutaneous T cell lymphoma (CTCL) patient, 4 lymphomatoid papulosis (LP) patients, 4 B cell lymphoma patients, and 2 actinic reticuloid (AR) patients. In MF, the monoclonality of the T cells became detectable first in the skin when plaques develop to tumors then in lymph nodes, and finally in the blood lymphocytes, indicating this disease develops from local (skin) malignancy to systemic malignancy. In parapsoriasis en plaque, no monoclonality was detected in any sample. We could distinguish cutaneous ATL from the carrier state by detecting the T cell monoclonality and HTLV-I integration with these probes. One patient with CTCL showed detectable T cell monoclonality; 1 out of 4 patients with LP did the same. Four samples from patients with B cell lymphoma revealed detectable monoclonal rearrangement of immunoglobulin heavy and light chain genes. In AR, no monoclonality was detected in any sample. From these data, we conclude that DNA analysis is useful in determining the monoclonality, cell origin, and distribution of monoclonal cells from skin samples.
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PMID:Characterization of the lymphoproliferative diseases in the skin by DNA analysis. 180 May 28


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