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)

During the course of serial passage of 50 human xenografts in the athymic mouse over a period of 5 years we have observed two cases of induction of sarcomas in the murine stromal tissue associated with the human xenografts. Both times the growth of the murine sarcomas overtook that of the human xenograft. This change was monitored by analysis of the lactate dehydrogenase isozyme profile and histology of each passage of the human xenografts in the athymic mice. The two murine sarcomas were subsequently established in tissue culture. The sarcoma cell lines were found to be malignant by morphological and growth characteristics and were tumorigenic. They contained large amounts of murine leukemia virus when assayed for reverse transcriptase activity by infection of mouse SC-1 cells and BALB/c and NIH Swiss fibroblasts with filtered supernates, and some type C virus particles were observed by electron microscopy in tumor tissues. However, we were unable to demonstrate the presence of murine sarcoma virus by in vitro transformation of fibroblasts or sarcoma formation in vivo will cell free filtrates. Preliminary biochemical data indicate that the sarcomas are extremely high in plasma membrane ATP phosphohydrolase.
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PMID:Induction of sarcomas in athymic mice. 628 53

A culture product of Streptomyces pseudovenezuelae MF722-02, with a molecular formula of C29H32N2O7, was isolated as yellow needles from culture broths and mycelia of the organism by means of a series of solvent extraction, column chromatography and crystallization. The antibiotic is active against some Gram-positive bacteria, inhibits growth in vitro of cells of mouse leukemia L-1210, prolongs the life span of mice inoculated with the leukemia cells, enhances deoxycholate-induced hemolysis in vitro and inhibits (Na+, K+)-ATPase in vitro.
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PMID:An inhibitor of (Na+, K+)-ATPase produced by Streptomyces pseudovenezuelae MF722-02; purification and properties. 629 65

The anthraquinone mycotoxins emodin and skyrin were examined for the inhibitory effects on murine leukemia L1210 culture cells, oxidative phosphorylation of rat liver mitochondria, and Na+, K+-activated ATPase activity of rat brain microsomes to find the differences between their modes of toxic action. Skyrin exhibited a stronger inhibitory effect than emodin on the growth of L1210 culture cells. Emodin showed a stronger uncoupling effect than skyrin on mitochondrial respiration. Skyrin inhibited Na+, K+-activated ATPase activity of rat brain microsomes but emodin did not inhibit.
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PMID:A comparative study on cytotoxicities and biochemical properties of anthraquinone mycotoxins emodin and skyrin from Penicillium islandicum Sopp. 632 Apr 99

Magnesium-dependent adenosine triphosphatase (Mg2+-ATPase) activities wee studied in human neutrophilic polymorphonuclear leucocytes. Kinetic studies on whole leucocyte homogenates produced curvilinear kinetics suggesting the presence of at least two forms of Mg2+-ATPase. Neutrophils were homogenized in isotonic sucrose and, after low-speed centrifugation, the supernatant was subjected to analytical subcellular fractionation. Gradient fractions were assayed for Mg2+-ATPase and for principal organelle marker enzymes. Mg2+-ATPase was distributed between the plasma membrane, mitochondrial and cytosol fractions. Kinetic and inhibitor studies on Mg2+-ATPase from each localization indicated the presence of three forms of the enzyme. The plasma membrane and mitochondrial activities had a Km value of 0.2 mmol/l for ATP, whilst the Km for the cytosolic enzyme was 1.8 mmol/l. Inhibitor studies showed further differences between the three enzymes. Neutrophils were isolated from control subjects, patients with chronic granulocytic leukaemia and patients in the third trimester of pregnancy. The specific activities (mUnits/mg protein) of Mg2+-ATPase, in contrast to those of alkaline phosphatase, were similar in all three patient groups. This result, together with the fractionation experiments and inhibitor studies, strongly suggest that the ATPase is not attributable to neutrophil alkaline phosphatase.
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PMID:Subcellular localization and properties of adenosine triphosphatase in human polymorphonuclear leucocytes. 645 79

Seven transplantable leukemias and lymphomas which occurred in NZB mice were characterized immunologically and cytologically as B-cell type of L66-, 2709-, 2769- find S77-lines, and T-cell type of TH17-, TH90- and S29-lines. These were also studied with enzyme histochemistry in tissue sections. All B-cell tumors revealed strong activities of ATPase and 5'-nucleotidase and one expressed A1Pase activity on the cell surface. Two thymic lymphomas (TH17- and TH90-lines) and one T-cell leukemia (S29-line) showed negative reactions of ATPase and 5'-nucleotidase but positive activities of AcPase and non-specific esterase localized in their cytoplasms. A1Pase activity was expressed in TH90-lymphoma but not in TH17- and S29-lymphomas. A1Pase recognized in L66- and TH90-lymphomas showed similar reaction to those of Nagao's isoenzyme. The splenic follicles of normal NZB mice reacted to ATPase and 5'-nucleotidase in B-cell area (primary follicles) and to AcPase and non-specific esterase in T-cell area (PALS) with the localized reaction. Data suggest that four enzymes of ATPase, 5'-nucleotidase, AcPase and non-specific esterase are useful for the differentiation of B- and T-cells and their malignant counterparts.
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PMID:Cytochemical markers of murine leukemias and lymphomas. 645 3

A recently developed procedure, that has been shown to be suitable for detailed immunohistological analysis, has been used to prepare cryostat sections of bone marrow to investigate whether enzyme-histochemical techniques are also feasible on such material. A selected group of enzymes, some of which are inhibited or destroyed in paraffin- or plastic-embedded samples, have been demonstrated. The morphological details obtained were satisfactory in the preparations. The enzymes were dipeptidyl(amino)peptidase IV (for T lymphocytes); tartrate-resistant acid phosphatase (for hairy cell leukaemia); acid phosphatase and non-specific esterase (for macrophages and monocytes); ATPase and 5'nucleotidase (for B lymphocytes); and peroxidase or chloroacetate esterase (for granulocytic cells). In these preparations strong enzyme activities were shown. In adjacent sections the immunological analysis of membrane markers could also be performed contributing to a comprehensive study of the normal and malignant bone marrow cells.
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PMID:Enzyme histochemical analysis on cryostat sections of human bone marrow. 714 30

Cytogeneticists recognize that karyotypic abnormalities are associated with specific malignancies. In 1960, Nowell described the Philadelphia chromosome (Ph) and its relationship to chronic myelogenous leukemia (CML). Subsequent work in molecular genetics and biology has revealed that the Ph is a translocation that causes fusion of gene sites that code for the break cluster region (BCR) and the avian blastic leukemia (ABL) proteins. This so-called fusion protein is present in a large percentage of the patients who have CML. A related fusion protein is seen in about one third of patients with acute lymphoblastic leukemia. The BCR-ABL fusion protein results in increased tyrosine kinase activity. The mechanism of action is thought to be via signal transduction related to guanosine triphosphatase activating protein which interacts with a ras-p21 binding protein. Acute promyelocytic leukemia (APL) is associated with the cytogenetic abnormality of t(15;17). This alters the promyelocytic leukemia (PML) and the retinoic acid receptor alpha (RARA) gene sites. Two fusion proteins are the result of this cytogenetic abnormality. They are termed PML-RARA and RARA-PML. Only one, the PML-RARA, is associated with APL. The PML-RARA chimeric protein has two zinc finger-like regions. It retains the ligand binding domain of RARA. The protein called PML has some similarities with a family of proteins which are thought to fuse to proto-oncogenes and to act as transforming proteins. The role of classical cytogenetics and the added capability of molecular biology has helped to elucidate some of the potential mechanisms for the development of cancer and provided additional understanding of neoplasia. (ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cytogenetics, gene fusions, and cancer. 748 13

In recent years, epidemiological studies have shown an increased risk of leukemia in children living near electric power distribution lines. Also, medical studies have shown that low frequency electromagnetic (EM) fields accelerate the healing of bone fractures. The stimulation of biosynthesis suggested by both epidemiological and clinical studies is observed in vitro, and indicates that EM fields stimulate the biosynthetic 'stress response' in cells. Studies of EM field effects on enzyme (Na,K-ATPase) function suggest that these effects should be considered in the design of molecular electronic devices.
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PMID:Biological effects of environmental electromagnetic fields: molecular mechanisms. 748 11

The p12I protein, a small hydrophobic protein encoded by the human T cell leukaemia/lymphotropic virus type I pX region, contains a proline-rich region located between two putative transmembrane (TM) domains. The p12I protein is associated with cellular endomembranes, and physically binds to the 16 kDa subunit of the vacuolar H+-ATPase proton pump. To investigate the nature of the 16 kDa and p12I interaction and to determine the oncogenic domain of p12I, we constructed p12I mutant proteins in which various portions of the TM domains were deleted, as well as p12I mutant containing a single amino acid substitution. These mutants were tested for binding to the 16 kDa subunit of the vacuolar H+-ATPase in HeLa/Tat cells and for the capability to potentiate transformation by bovine papillomavirus type 1 E5 oncoprotein in mouse C127 cells. The results indicated that both TM domains of the p12I protein were dispensable for its interaction with the 16 kDa protein, whereas partial or complete deletion of the proline-rich region resulted in decreased or no binding of the p12I protein to the 16 kDa subunit. Immunofluorescence analysis of HeLa/Tat cells transfected with the p12I mutants showed that deletion of the proline-rich region did not alter the subcellular localization of these mutant p12I proteins, suggesting direct involvement of the proline-rich domain in binding rather than the failure of these p12I mutants to reach the appropriate cellular compartment. Mapping of 16 kDa subunit mutants in binding with p12I protein suggested that molecular determinants located between the second and third TM domain of the 16 kDa protein might be involved in this interaction. Finally, most of the p12I mutants lost the ability to potentiate transformation of C127 cells indicating that binding of p12I to the 16 kDa subunit does not directly correlate with oncogenicity.
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PMID:Mapping of the intermolecular association of human T cell leukaemia/lymphotropic virus type I p12I and the vacuolar H+-ATPase 16 kDa subunit protein. 763 72

Cyclopiazonic acid has been reported to inhibit the Ca(2+)-ATPase of intracellular calcium stores in some nonexcitable cell types, such as myeloid cells and lymphocytes. The present study examines the effects of cyclopiazonic acid on rat basophilic leukemia (RBL) cells, a mucosal mast cell line. Addition of cyclopiazonic acid to fura-2-loaded RBL cells evoked a biphasic increase in free ionized intracellular calcium. Release of stored calcium accounted for the first phase of this response. The second phase was determined to be calcium entering through an influx pathway activated by cyclopiazonic acid. The influx pathway was selective for calcium, but was somewhat permeable to manganese. However, in a Ca(2+)-free solution containing EGTA, sodium ions permeated freely. This influx pathway appears to be identical to that which is activated by antigen, the physiological stimulus to the cells. Cyclopiazonic acid also induced secretion when combined with the phorbol ester 12-O-tetradecanoyl phorbol 13-acetate, which activates protein kinase C.
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PMID:Ca(2+)-ATPase inhibitor, cyclopiazonic acid, releases Ca2+ from intracellular stores in RBL-2H3 mast cells and activates a Ca2+ influx pathway that is permeable to sodium and manganese. 779 Mar 92


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