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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To test the feasibility of using the human epidermal growth factor receptor (EGFR) as a model for growth factor receptor action in human hematopoietic cells, we infected Burkitt lymphoma cells (Namalwa) with a recombinant amphotrophic retrovirus containing a thymidine kinase promoter-driven human EGFR complementary DNA and the neomycin resistance gene. Neomycin-resistant cells expressing surface EGFR were selected by cell sorting using anti-EGFR monoclonal antibody 225. The selected cells expressed a Mr 170,000 protein immunoprecipitated by monoclonal antibody 225 and apparently identical to EGFR from A431 carcinoma cells. Infected Namalwa cells expressed 42,000 epidermal growth factor (EGF) binding sites/cell, and Scatchard analysis showed two affinities (Kd approximately 5 nM and approximately 0.5 nM). EGFR autophosphorylation was detected using antiphosphotyrosine antibodies after 5 min exposure to EGF. EGF binding induced rapid EGFR internalization (t1/2 = 9 min) and mobilization of transferrin receptors to the cell surface within 1 min. In fetal bovine serum-containing and serum-free cultures, EGF did not stimulate Namalwa cell proliferation. However, in the presence of 1.25% dimethyl sulfoxide (DMSO), EGF caused a dose-dependent increase in DNA synthesis. DMSO induced a cell cycle block in G1, which was partially reversed by EGF. DMSO induced changes in some B-cell markers suggesting cellular differentiation and increased surface EGF receptor number. Cells grown in DMSO and EGF were established as an EGF-dependent cell line for greater than 12 weeks, whereas cells grown in DMSO without EGF died within 1-2 weeks. Namalwa cells expressing EGFR demonstrated more rapid tumor growth in athymic mice. These studies demonstrate expression of functional EGFR mediating early biochemical and growth responses in a human hematopoietic cell, and indicate that EGFR can be used as an effective model in human hematopoietic cells. Results using DMSO are consistent with studies in other human leukemia cells indicating that agents inducing differentiation can restore growth factor dependence in previously factor-independent leukemia cells.
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PMID:Expression of functional epidermal growth factor receptors in a human hematopoietic cell line. 170 31

Directly growing Epstein-Barr virus (EBV)-carrying cell lines were established from a chronic lymphocytic leukemia (CLL) patient (PG) on repeated occasions. The lines carried the same ring chromosome 15 as the leukemia cells in vivo and were similarly trisomic for chromosome 12. They all showed the same JH rearrangement, indicating that they had arisen from the same B-cell progenitor. They also had the same single EBV-terminal repeat (TR), indicating that they had been generated by a single EBV infection event. It may be surmised that a single CLL cell had been infected by EBV in vivo and established itself subsequently as a subclone within the CLL population. This subpopulation persists in vivo but does not appear to expand with time. After explantation, it transforms into lymphoblastoid cells and proliferates selectively as immortalized lines. The leukemia-representative CLL lines were phenotypically indistinguishable from the B95-8 virus-transformed normal diploid cells of the patient, established in parallel by in vitro infection. They grew as typical LCL clusters and expressed the same B-cell activation markers. The methylation status of EBV-DNA was different in the CLL lines and the B95-8-virus-transformed LCLs. When Hpall- and Mspl- digested DNA was probed with BamHI C, E, H and W fragments, the CLL lines showed a mixture of methylated and unmethylated restriction fragments as in certain EBV-carrying Burkitt lymphoma (BL) lines. In contrast, the EBV-DNA of B95-8 virus-transformed normal diploid cells was completely unmethylated, as in other LCLs.
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PMID:Clonality and methylation status of the Epstein-Barr virus (EBV) genomes in in vivo-infected EBV-carrying chronic lymphocytic leukemia (CLL) cell lines. 185 Mar 84

Tumour cell karyotypes from patients with Burkitt lymphoma (BL) or Burkitt's type leukemia (ALL3) were studied for correlation with survival, bone marrow and cerebral spinal fluid involvement (CSF), human immunodeficiency virus (HIV) serology, and for recurrent cytogenetic abnormalities. The records of 22 patients with BL from our institution and of 148 cases of BL and ALL3 reported in the literature with karyotypes were evaluated for clinical and cytological features. Overall survival was only 28 per cent and 88 per cent of deaths occurred within the first nine months after diagnosis. Those who survived at least 18 months were unlikely to relapse. Age and gender did not significantly affect survival. Patients presenting with advanced Ann Arbor stage, bone marrow or CSF involvement had lower survival rates. The association of translocations involving chromosome band 8q24 with this disease is confirmed. Sixty-two per cent of karyotypes had t(8;14)(q24;q32) translocations; the recognized variant translocations t(8;22)(q24;q11) and t(2;8)(p12;q24) affected 12 per cent and 9 per cent respectively. Seventeen per cent had abnormal karyotypes but no classic translocation. Patients with variant translocations had the poorest survival rates, and those with the classic t(8;14)(q24;q32) did the best. Despite a small sample size, the variant translocation t(8;22)(q24;q11) appeared to occur at an increased frequency in the patients with AIDS. In the entire group, recurrent involvement of chromosome regions 1q2, 6q11-14 and 17p1 suggests that alteration of genes at these loci, B Cell Growth Factor (BCGF) at 1q2 and p53 on 17p, may contribute to the development and progression of this tumour. Similarly, the frequent trisomies of chromosomes 7, 8, 12 and 18 may indicate an effect on tumour cell growth due to increased gene dosage. Trisomy 12 was found in eight tumours, five from patients with AIDS, suggesting that chromosome 12 has a site or gene whose allelic dosage is selected for in AIDS related lymphoma cells. Cytogenetic studies of adult Burkitt lymphoma and leukemia suggest several likely loci for gene alterations that in conjunction with myc translocations can lead to tumorigenesis.
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PMID:Chromosomal abnormalities in adult non-endemic Burkitt's lymphoma and leukemia: 22 new reports and a review of 148 cases from the literature. 186 43

An antigen with a molecular weight of 150 kilodaltons expressed on certain leukemia and lymphoma cells was recognized by a human monoclonal antibody (3H12), which had been established by the fusion of lymphocytes from a small cell lung cancer patient with a mouse myeloma cell line (P3U1). Peripheral blood mononuclear cells from 3 out of 4 cases with lymphoid crisis of chronic myelogenous leukemia (CML) were positively stained by 3H12, while cells from 5 cases with myeloid crisis of CML did not react to this antibody. The antibody did not show any reactivity to cells from the chronic phase of CML, other types of leukemias or normal hematopoietic cells. We further examined 29 cell lines of hematopoietic origin and found that 2 undifferentiated cells (BV-173 and K-562) reacted to the 3H12 antibody. In addition, we found that 3 out of 6 Burkitt lymphoma cells (DAUDI, RAJI and HR1K) reacted to 3H12. Taken together, these results suggest that the antigen recognized by 3H12 is a differentiation-associated antigen expressed on immature lymphoid cells, and could potentially be a reliable cell lineage marker.
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PMID:Human monoclonal antibody detects a cell surface antigen expressed on hematopoietic malignant cells of lymphoid lineage. 190 Aug 25

Usefulness of DNA analysis in diagnosis of hematopoietic malignancy was discussed. Examination on the presence of rearrangement in immunoglobulin (Ig) and T cell receptor (TCR) was the first DNA analysis used for clinical diagnosis of lymphoid malignancy to determine the cell-lineage and clonality of proliferating lymphoid cells. One point mutation in ras oncogene has also been used to detect residual leukemic cells as well as diagnosis of the early relapse of leukemia, although not all leukemic cells have this mutation. Presence of BCR-abl fused gene is a genetic marker for Ph1 chromosome. Analysis of BCR-abl gene has made it possible to diagnose the Ph1 ALL and masked Ph1 CML. Development of PCR technique markedly increased the possibility for the use of DNA analysis in clinical medicine. In addition to Ph1 chromosome, various chromosomal abnormalities resulted in a reciprocal translocation between Ig or TCR gene and other genes in various lymphoid malignancies, such as Burkitt lymphoma and follicular lymphoma. These translocations can be analyzed by Southern hybridization and used for clinical diagnosis.
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PMID:[DNA diagnosis of human cancers: lymphoid malignancies and leukemia]. 198

Interleukin 1 (IL-1) has been obtained from the Epstein-Barr virus-infected B-lymphoblastoid cell line 3B6 and shown to be involved in autocrine growth of 3B6 B cells. Independently, adult T-cell leukemia-derived factor (ADF) was purified from human T-lymphotropic virus I-infected leukemic T-cell line (ATL-2) and reported as an interleukin 2 (IL-2) receptor-inducing factor. We have previously reported the same molecular mass, pI, and NH2-terminal amino acid sequence for both 3B6-derived IL-1 and ADF. cDNA cloning of ADF demonstrated high homology with the prokaryotic disulfide reducing enzyme thioredoxin. We show here that ADF and 3B6-derived IL-1 are identical. By RNA blot, 3B6 and ATL-2 cells were shown to contain high levels of 0.6-kilobase mRNA corresponding to ADF. Such message was not detected in resting peripheral blood lymphocytes but could be weakly induced by lymphocyte activation. Antibodies have been raised against synthetic peptides corresponding to the NH2 terminus and the COOH terminus of ADF. Immunoblotting and sequential immunoprecipitation with these antibodies revealed the same 13-kDa protein in 3B6 and ATL-2 cells. Recombinant ADF could sustain growth of 3B6 and ATL-2 cells at low cellular concentration without fetal calf serum; ADF, thus, appears involved in their autocrine growth. Similarly, recombinant ADF could enhance growth of other B-cell lines, including the Epstein-Barr virus-negative Burkitt lymphoma line BL41 and the lymphoblastoid cell lines CRAG8, CRB95, and 1G8. Finally, recombinant ADF exhibits marked synergism with other cytokines, such as IL-1 and IL-2, allowing virally infected lymphocytes to respond to suboptimal amounts of a variety of growth factors.
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PMID:Adult T-cell leukemia-derived factor/thioredoxin, produced by both human T-lymphotropic virus type I- and Epstein-Barr virus-transformed lymphocytes, acts as an autocrine growth factor and synergizes with interleukin 1 and interleukin 2. 217 79

Although determination of chromosomal abnormalities may be of limited usefulness for the diagnosis of leukemia, the recent advances in the molecular mechanism associated with chromosome aberration has been rapid. Chromosome translocation in Burkitt lymphoma and chronic myeloid leukemia was the most striking evidence for the oncogene activation. Other specific chromosome abnormalities for FAB-classified leukemias are also known. Translocated type of chromosome abnormalities between immunoglobulin or T-cell receptor genes and oncogenes may also affect the T and B-cell leukemogenesis. However, the role of trisomies found in human and experimental leukemias and the gene dosages had been thought to be most important until 1982, has not been unclear. Many types of phenotypically heterogeneous leukemias have been reported. t(4 ; 11) acute leukemia is one such leukemia which shows early B-cell and myelomonocytic nature. Heterogeneous leukemias have been called biphenotypic, hybrid and acute mixed leukemias. The terminology must be used the unified. Recent trials to use paraffin-fixed tissues and bone marrow smear for molecular analysis has been successfully reported. Basic analysis on the DNA degradation mechanism revealed the enzymatic activity might play an important role before the complete fixation.
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PMID:[Chromosome aberrations and genes in human and experimental leukemias]. 219 1

Persisting DNA of parvovirus H-1 could be demonstrated in cells of two human lymphoma cell lines, the Burkitt lymphoma cell line BL2 and the T-cell leukemia cell line Jurkat which survived infection with parvovirus H-1. Persistence of H-1 DNA rendered the cells resistant to a second H-1 infection. This resistance to H-1 superinfection persisted even after loss of H-1 DNA occurring after approximately 150-200 cell generations. Resistance to H-1 superinfection was accompanied by reduced uptake of infectious particles and by a block of H-1 DNA replication. This suggests that persistent H-1 infection leads to modifications of cellular functions involved in the permissivity for H-1.
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PMID:Persistence of parvovirus H-1 DNA in human B- and T-lymphoma cells. 238 60

Several monoclonal antibodies (MAbs) directed to blood group P1 (Gal alpha 1-4Gal beta 1-4GlcNAc beta-O) and Pk (Gal alpha 1-4Gal beta 1-4Glc beta-O) determinants were produced with high efficiency by using synthetic neoglycoproteins as immunogens. The specificity of IgM and IgG1 MAbs was characterized by binding to defined oligosaccharides and glycoconjugates. Antibodies that bound equally well to P1 and Pk determinants and to Gal alpha 1-4Gal beta 1-O-derivatives were obtained, together with others that showed selective recognition of the entire trisaccharide chain. Selected antibodies were shown to be useful as reagents for detection of the blood group P antigens in glycolipid extracts of erythrocytes and on the surface of erythrocytes of different P phenotypes, demonstrated both by radioimmune assays and hemagglutination. Six IgM MAbs directed to the Pk determinant bound selectively to Burkitt lymphoma cells and 2 of these antibodies (424/3D9 and 424/6A2) could be used as auxiliary reagents in immunofluorescence for diagnosis and classification of B-cell lymphomas and leukemias using flow cytometric analysis. Eight normal individuals and 37 patients with lymphoma or leukemia were studied. Tumor cells of 2/2 patients with "Burkitt-like" lymphoma, 1 patient with centroblastic lymphoma and 2 patients with acute leukemia were strongly stained for the Pk antigen. The staining patterns for differentiation markers classified the tumor cells to a developmental stage closely related to the Burkitt cell type.
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PMID:Monoclonal antibodies produced by immunization with neoglycoproteins containing Gal alpha 1-4Gal beta 1-4Glc beta-O and Gal alpha 1-4Gal beta 1-4GlcNAc beta-O residues: useful immunochemical and cytochemical reagents for blood group P antigens and a differentiation marker in Burkitt lymphoma and other B-cell malignancies. 245 94

A novel dye exclusion assay based on differential staining of fixed cells has been evaluated using the MOLT4 (T-lymphoblastic leukaemia) and DAUDI (Burkitt lymphoma) cell lines. Reproducible differential staining was found with fixed samples kept for up to 2 months. A small increase (less than 13%) in the proportion of stained cells was observed over the first 30 days in fixative. Reproducible dose-response data were obtained with cells treated with radiation or drugs and assayed after 4 days in culture. This ability to fix cells prior to measurement of viability is of general use particularly where time constraints prevent haemocytometer counting. More specifically, it may have potential use in the field of chemosensitivity testing particularly where large sample numbers require rapid processing.
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PMID:A novel dye exclusion assay for measurement of cell response following in vitro exposure to radiation or drugs. 247 98


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