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)

Insulin and the insulin-like growth factors (IGF-I, IGF-II) constitute a family of peptides capable of stimulating diverse cellular responses, including cell proliferation. In order to determine the effects of these peptides on malignant cells, we analyzed the expression and function of insulin, IGF-I, and IGF-II receptors on B-cell precursor acute lymphoblastic leukemia (BCP ALL) cell lines, utilizing competitive binding, affinity crosslinking, and cell proliferation assays. The BCP ALL cells bound to each peptide with mean specific binding for 125I-insulin, 125I-IGF-I, and 125I-IGF-II of 19.6%, 7.1%, and 4.3% of radioligand added, respectively. Competitive binding to intact cells demonstrated that 125I-IGF-I was displaced by IGF-I = IGF-II >> insulin, 125I-IGF-II was displaced by IGF-II > insulin = IGF-I, and 125I-insulin was displaced by insulin >> IGF-II > IGF-I. These data were remarkable for the potency of IGF-II displacement of 125I-IGF-I and 125I-insulin. Affinity crosslinking of radioligands to SUP-B2 cell membranes demonstrated the high affinity insulin and IGF-I (type 1 IGF) receptors. IGF binding proteins were also present in BCP ALL cell membrane preparations. In the cell proliferation studies, insulin stimulated a 50-130% increase in leukemic cell growth with a half-maximal concentration of 0.1-3.0 ng/ml in three BCP ALL cell lines. The proliferative response to insulin was blocked by the addition of an insulin receptor antibody. However, no response was observed with IGF-I, and IGF-II was only weakly mitogenic with a proliferative response noted at 100 ng/ml. Thus, while BCP ALL cells possess receptors for insulin and IGF-I, only the insulin receptor mediated a proliferative response.
Leukemia 1992 Nov
PMID:Mitogenic effects of human recombinant insulin on B-cell precursor acute lymphoblastic leukemia cells. 143 95

Rhesus peripheral blood mononuclear cells (PBMC) fail to demonstrate natural killer (NK) activity against the human T-cell lines CEM, CEM x 174, or SUP-T1. However, these cell lines could act as NK-sensitive target cells if they were pulsed with heat-inactivated, whole simian immunodeficiency virus (SIV). The ability of these SIV-pulsed T-cell lines to act as NK-sensitive target cells was directly related to the relative density of CD4 on their surface. Target cell generation was inhibited by preincubation of cell lines with CD4 monoclonal antibody (MAb) with specificity for the SIV binding site. In addition, NK activity was seen against target cells that had been prepared with human immunodeficiency virus type 1 (HIV-1) gp120, nonglycosylated gp120, env A of feline leukemia virus (FeLV), and simian type D retrovirus (SRV). Addition of leupeptin to target cells prior to SIV pulsing did not result in a significant decrease in cytotoxic activity, suggesting that processing is not required for the generation of target cells. The cells that mediate NK activity are nonadherent, do not form rosettes with AET-treated sheep red blood cells (SRBC), and are phenotypically CD16+ and CD8+. NK activity of SIV-infected macaques was significantly decreased against both K562 cells and SIV-pulsed target cells as compared with uninfected animals. However, treatment of PBMC with interleukin-2 (IL-2) resulted in a partial restoration of NK activity.
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PMID:Natural killer cell activity of rhesus macaques against retrovirus-pulsed CD4+ target cells. 197 94

Non-random translocation involving the short arm of chromosome 19 are frequently observed in acute leukemias. Recent studies have shown that the 19p13 genes E2A and LYLl, both of which encode helix-loop-helix proteins, lie at two different translocation breakpoints in acute lymphoblastic leukemias (ALL). The E2A gene is involved by the t(1;19)(q23;p13) in acute pre-B-cell leukemias and the LYL1 gene is structurally altered by a t(7;19)(q34;p13) in T-cell ALL. To assess the role of these genes in other leukemia-associated translocations we mapped their locations with respect to the t(11;19)(q23;p13) and t(4;19)(q21;p13) translocation breakpoints carried by T-ALL cell lines SUP-T13 and SUP-T8a, respectively. In situ hybridization studies indicated that the E2A and LYL1 genes are physically distinct from the t(4;19) and t(11;19) breakpoints. Using these and other 19p13 translocation breakpoints as landmarks, we established a partial physical map of 19p: 19pter-E2A-INSR-LYL1-[t(4;19)]-19cen. These data should help guide molecular studies to further characterize 19p13 breakpoints and mapping of genes in this chromosomal region.
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PMID:Mapping of translocation breakpoints on the short arm of chromosome 19 in acute leukemias by in situ hybridization. 226 76

The cytokine secreted by a human hybrid B cell line (STS 25) obtained by fusion of the B lymphoblastoid cell line WI-L2-729-HF2 with neoplastic B cells from a patient with B cell non-Hodgkin's lymphoma (B-NHL) was characterized as IL-1 alpha. STS 25 cells express the idiotypic (Id+) immunoglobulin (Ig) specific for the neoplastic B cells of the B-NHL patient. STS 25 cells are weakly positive for surface mu delta kappa and in addition express the surface markers CD19, CD20, CD23, HLA class I and II, and the 4F2 activation antigen. STS 25 cells are also Epstein-Barr nuclear antigen positive but do not secrete viral particles. Serum-free culture supernatant from STS 25 cells (STS 25 SUP) does not show activity in assays for interleukin-2 (IL-2), -4 (IL-4), -6 (IL-6), interferon or tumor necrosis factor, but is active in the thymocyte costimulation assay and the D10.G4.1 T helper clone proliferation assay for interleukin-1 (IL-1). The IL-1 character of the STS 25 SUP activity was confirmed in inhibition studies with three different poly- or monoclonal anti-IL-1 antibodies (31, 88, and 94% inhibition in thymocyte costimulation assay, respectively). Furthermore, complete blocking of D10.G4.1 cell proliferation mediated by STS 25 SUP was observed by including anti-IL-1 alpha specific antibody in the assay, whereas anti-IL-1 beta antibody had no effect. These results indicate that this STS 25 SUP activity can be attributed to the presence of IL-1 alpha in the supernatant. Northern blot analysis of total STS 25 cellular RNA using IL-1 alpha or IL-1 beta specific probes revealed the constitutive expression of IL-1 alpha messenger RNA by STS 25 cells. In contrast, no IL-1 beta message was detectable, not even after treatment of the cells with phorbol ester or cycloheximide, which resulted in approximately 5-fold enhancement of IL-1 alpha mRNA expression. Binding studies with radiolabeled recombinant (r) IL-1 alpha indicated the presence of high numbers of IL-1 receptors on STS 25 cells (1,170 per cell, Kd = 392 pM). Although both IL-1 alpha and IL-1 beta bound to these IL-1 receptors, no indication was found for IL-1 mediated regulation of STS 25 cell growth.(ABSTRACT TRUNCATED AT 400 WORDS)
Leukemia 1989 Aug
PMID:Functional and molecular characterization of B cell line derived interleukin-1 alpha. 278 53

Serum thiobarbituric acid (TBA) reactivity for lipoperoxidation products was assessed at diagnosis in children with T-cell and common acute lymphocytic leukemia (ALL) and T-lymphoblastic lymphoma. Comparisons were made among these groups and with healthy controls. Mean TBA reactivity (mumol malondialdehyde/L serum) was increased (P less than 0.01) in the T-cell leukemia group versus common ALL and T-lymphoblastic lymphoma patients and controls, respectively. The increase in lipoperoxidation products in T-cell ALL appeared to bear a positive relation to peripheral leukocyte counts, and was accompanied by increased serum prostaglandin E2 (PGE2) levels in most representative cases. Indomethacin added to a childhood T-cell ALL line (SUP-T3), at a concentration known to inhibit prostaglandin synthesis in vitro (i.e., 3 micrograms/mL), effected significant increases in the numbers of natural killer (NK; Leu-11+ and Leu-19+) cells (P less than 0.01) and B-lymphocytes (P less than 0.05), and significant decreases in cell viability (P less than 0.01). Indomethacin may be a useful agent for enhancing the antileukemic immune response in T-cell ALL.
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PMID:Lipoperoxidation and T-cell leukemia of childhood. Effects of indomethacin. 280 98

A translocation between chromosomes 7 and 9, t(7;9), has been described in cell lines derived from the malignant cells of children with acute T-cell lymphoblastic leukemia or lymphoma. Our cytogenetic analysis of one such cell line, SUP-T3, demonstrates that the breakpoints on chromosomes 7 and 9 lie within bands q36 and q34, respectively, corresponding to the location of the gene encoding the beta chain of the T-cell receptor, TCRB, and the gene homologous to the transforming gene of the Abelson murine leukemia virus, ABL. We investigated the role of these genes in the t(7;9). In situ chromosomal hybridization of TCRB and ABL probes to metaphase cells from SUP-T3 demonstrated that ABL is translocated from chromosome 9 to 7 and that all or part of TCRB is translocated from chromosome 7 to 9. Southern blot analysis revealed that both TCRB alleles were rearranged; however, it could not be determined whether the translocation breakpoint lies within this gene. Pulsed-field gel electrophoresis and Southern blot analysis were used to examine more than 500 kilobases of the ABL locus; we concluded that there are no rearrangements within 250 kb in either direction of the sequences homologous to v-abl. Additionally, no abnormal ABL protein was detected in an in vitro phosphorylation assay. These results indicate that, in SUP-T3, the breakpoint on chromosome 9 lies proximal to ABL and that the break results in no apparent alteration of the ABL protein. We therefore hypothesize that another gene on chromosome 9, at band q34, plays a role in this translocation. This study also demonstrates that pulsed-field gel electrophoresis is a powerful new tool for the analysis of human chromosomal translocations.
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PMID:Molecular analysis of TCRB and ABL in a t(7;9)-containing cell line (SUP-T3) from a human T-cell leukemia. 302 59

DNA spanning a t(7;19) chromosomal translocation breakpoint was isolated from the human T cell line SUP-T7 established from an acute lymphoblastic leukemia. Nucleotide sequence analysis showed that the point of crossover on chromosome 7 occurred immediately adjacent to joining segment J beta 1.1 within the TCR-beta gene, suggesting that this translocation resulted from an error in TCR gene rearrangement. On chromosome 19, the translocation occurred within a previously uncharacterized transcriptional unit for which we propose the name lyl-1. An approximately 1.5-kb RNA is transcribed from this gene in a wide variety of hematolymphoid cell lines. The t(7;19) results in truncation of the lyl-1 gene and production of abnormal-sized RNAs, suggesting a role for lyl-1 in the pathogenesis of this leukemia.
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PMID:Chromosomal translocation involving the beta T cell receptor gene in acute leukemia. 316 54

A monoclonal antibody (mAb), 2D1(IgM), was identified for its anti-proliferative effect on human T leukemia cell line, SUP-T13. The cells bound with 2D1 showed DNA ladder patterns of oligonucleosomes, demonstrating apoptosis. Peripheral mononuclear cells activated by phytohemagglutinin or OKT3 induced expression of 2D1 antigen and were growth-inhibited by the antibodies. Among the cell lines tested, T cell lines tended to be growth-inhibited by the antibodies. Epstein-Barr virus-transformed B cells were reactive with 2D1, but were not growth-inhibited by the antibodies. We established stable 2D1-resistant variants LAC2D1R and JKT2D1R from the original SUP-T13 and Jurkat T cell lines, respectively. These variant cells demonstrated phenotypes identical to the original cells, including reactivity to 2D1 and expression of cytoplasmic Bc1-2 protein. The 2D1-resistant cells were as sensitive as the original cells to the other apoptosis-inducing stimuli, such as gamma-irradiation or calcium ionophore A23187. However, the 2D1-resistant variants were also insensitive to anti-Fas, another apoptosis-inducing mAb. Binding of 2D1 was blocked by anti-Fas mAb, suggesting that 2D1 reacts with an epitope of human Fas molecules. The present results demonstrate that a 2D1-reactive, but not 2D1-sensitive, population may exist in highly 2D1-sensitive human leukemia T cells and that pairs of 2D1-sensitive and 2D1-resistant cells are useful in the biochemical analysis of Fas-mediated apoptosis in human T cells.
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PMID:Establishment of apoptosis-inducing monoclonal antibody 2D1 and 2D1-resistant variants of human T cell lines. 768 10

The complement receptor type 1 (CR1) is a membrane glycoprotein expressed on a variety of cells including some, but not all, human T lymphocytes. The present study was designed to investigate CR1 expression on human leukemia-derived CD4+ T cell lines. The expression of CR1, as well as the complement receptor type 2 (CR2) and membrane cofactor protein (MCP), were analyzed on cells from the SUP-T1, CEM-SS, HUT-78, and MOLT-3 cell lines by flow cytometry. All four cell lines expressed CR2 and MCP, but only the SUP-T1 cell line contained CR1+ cells. Within the SUP-T1 cell line, a mean of 8.5% of the cells were CR1+. Scatchard analysis indicated that approximately 2700 CR1 molecules were expressed per CR1+ SUP-T1 cell, a value that corresponds to the quantitative expression of CR1 on normal peripheral blood T lymphocytes. Separation of CR1+ and CR1- cells within the SUP-T1 cell line by flow cytometry and subsequent reculture of the sorted cells showed that both the enriched CR1+ and the enriched CR1- cell populations returned to a mixed CR1 phenotype over time. These data suggest that SUP-T1 cells can express CR1, but only transiently. Two-color flow cytometric analysis indicated that the expression of CR1 by SUP-T1 cells did not fluctuate with the cell cycle. SUP-T1 cells were also cultured in the presence of agents known to activate T cells. Phytohemagglutinin and phorbol 12-myristate 13-acetate induced a transient increase in the percentage of SUP-T1 cells expressing CR1, compared to cells cultured in media alone. These results suggest that CR1 expression is up-regulated during T cell activation. The CR1+ SUP-T1 cell line, as well as the CR1- cell lines, may provide useful models for investigating how CR1 expression is regulated and for exploring a possible role for CR1 in the pathogenesis of AIDS.
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PMID:Expression of the CR1 receptor on human leukemia-derived CD4+ T cell lines. 775 24

The SUP-T13 cell line, a human T leukemia, is susceptible to apoptosis by various inducers, including anti-TCR mAb, calcium ionophores, and anti-fas mAb. Induction of apoptosis by these three agents was investigated, and several differences were found. All three agents induced DNA fragmentation with a similar time course, but the kinetics of cell death were different for the three agents. Anti-TCR mAb-induced apoptosis, but not A23187- or anti-fas-induced apoptosis, was rescued by anti-CD3 mAb treatment. In contrast, only anti-fas mAb-mediated apoptosis was rescued by PKC activators such as PMA. These differences suggest that each of these three agents mediate apoptosis by unique signaling pathways. Nevertheless, two variant subclones of SUP-T13 were found to be resistant to all three apoptosis-inducing agents, suggesting a point(s) of common regulation between the different pathways. To determine whether this regulation occurred through bcl-2, p53, or c-myc, their expression in the parental and variant cells was determined. The three clones expressed approximately equal amounts of these proteins, and their levels did not change significantly upon treatment with anti-TCR or anti-TCR plus anti-CD3 mAb. Thus, although the proximal signaling by various apoptosis inducers were quite different, a common mediator(s) (as yet unknown) may still regulate apoptosis induced by these multiple agents.
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PMID:Comparison of apoptosis signaling through T cell receptor, fas, and calcium ionophore. 854 78


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