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)

2',3'-dideoxycytidine (ddC) inhibits replication of the immunodeficiency inducing strain of feline leukemia virus (FeLV-FAIDS) in vitro at concentrations ranging from 1-10 micrograms/ml. Additive antiviral effect is achieved when ddC is combined with either human recombinant alpha interferon (IFN alpha) or tumor necrosis factor (TNF) plus IFN alpha. Initial in vivo pharmacokinetic studies in cats, utilizing bolus intravenous administration of ddC (20 mg/kg), resulted in peak plasma concentrations of 15 micrograms/ml 1 min after administration and a half-life of approximately 1 h. These values could not be augmented with high levels of the deaminase blocker tetrahydrouridine administered prior to or concurrently with ddC. In vivo trials utilizing multiple, daily intravenous injections of ddC could not prevent the development of persistent viremia in cats infected with FeLV-FAIDS. To enhance ddC pharmacokinetics and antiviral activity, controlled release capsular implants were developed by blending ddC with a copolymer consisting of DL-lactide glycolide and hydroxypropyl cellulose, which was melt-spun into fibers and encapsulated in a sheath of polyethylene glycol for subcutaneous implantation. Pharmacokinetic studies, conducted in cats receiving an average dose of 600 mg of ddC, indicated an average peak plasma concentration of 17 micrograms/ml achieved at 6 h post implantation with 3.5 micrograms/ml noted at 48 h; and an extension of plasma half-life from 1.5 (bolus subcutaneous injection) to 20 h. sustained plasma concentrations of 1.5 to 10 micrograms/ml, equivalent to ddC levels previously shown to have anti-FeLV activity in vitro, were maintained throughout a 72 h period. Implantation devices could be replenished every 48 h and elevated plasma levels were sustained for four weeks without signs of clinical toxicity, sepsis or significant alterations in the hemogram. Initial clinical trials employing controlled release capsular ddC implants in vivo indicate significant retardation of FeLV-FAIDS replication throughout a four week treatment period.
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PMID:Treatment of FeLV-induced immunodeficiency syndrome (FeLV-FAIDS) with controlled release capsular implantation of 2',3'-dideoxycytidine. 254 37

5-Ethynyl-1-beta-D-arabinofuranosylcytosine (EAC) was prepared from 1-(2,3,5-tri-O-acetyl-beta-D-arabinofuranosyl)cytosine by iodination followed by coupling with (trimethylsilyl)acetylene and deblocking. At 50 microM, EAC was found to inhibit the in vitro replication of herpes simplex virus type 1 and type 2 by greater than 99%. EAC also showed activity against a strain of HSV-1 resistant to (E)-5-(2-bromovinyl)-2'-deoxyuridine which has an alteration of the virus-induced thymidine kinase (TK). At 100 microM, EAC did not inhibit the in vitro growth of leukemia L1210 and HeLa cells. EAC was resistant to the action of dCR-CR deaminase, its rate of deamination being approximately 2% that of dCR. The compound was a poor substrate for dCR kinase, but it was phosphorylated by HSV-1- and HSV-2-induced TKs at 50% and 30%, respectively, the rate of thymidine.
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PMID:Acetylenic nucleosides. 4. 1-beta-D-arabinofuranosyl-5-ethynylcytosine. Improved synthesis and evaluation of biochemical and antiviral properties. 282 32

Mice--BDF, hybrides, males aged 3 months were injected intraperitoneally with 10(4) lymphatic leukemia cells P 388. The mice were killed by bleeding after 2.5 and 10 days after the injection. Gamma-glutamyltransferase (GGT), leucylaminopeptidase (LAP) and cobalt activated acylase activity were determined in the serum of the mice. The inner organs of the animals were verified histopathologically. A statistically significant increase in the activity of the examined enzymes was observed together with the development of transplantable leukemia. These enzymes can be helpful in early monitoring of lymphatic leukemia P 388 in mice--as markers of cancer growth.
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PMID:Activity of some hydrolases in mice with transplantable lymphatic leukemia P 388. 288 60

The activity of cobalt-activated acylase was determined in the serum of mice with transplantable leukemia (P 388, L 1210 standard, L 1210/ara-C, L 1210/CH3-G, plasmocytoma ADJPC-5, lymphoma AKSL-4 and natural leukemia in mice NZB). A statistically significant increase in enzyme activity in all leukemias except lymphatic leukemia has been demonstrated. The results suggest possibility of using the enzymatic measurement as a marker of transplantable leukemia in mice.
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PMID:Serum cobalt-activated acylase as a marker of transplantable leukemia in mice. 327 96

The in vivo development of an ara-C-resistant leukemic cell line is reported in a rat leukemia model (BNML) that is generally accepted as a relevant model for human acute myelocytic leukemia. It took 32 continuous leukemia transplant generations, performed over 20 months, and a total dose of 28.5 g ara-C/kg to induce complete resistance. Preliminary data indicate that the development of ara-C resistance is related with decreased intracellular levels of deoxycytidine kinase. Deoxycytidine deaminase levels were not increased. Thus this enzyme does not seem to be involved with induction of resistance. This preclinical rat model for human AML provides a solid basis for studies in depth on the mechanism(s) and possible prevention and effective treatment of resistance to ara-C.
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PMID:In vivo development of cytosine arabinoside resistance in the BN acute myelocytic leukemia. 347 77

AKR mice highly susceptible to leukemia were fed orally for 9 months every days with a water solution of peat-liking preparation PF-290/II/2 at a dose 0.2 cm3 (70 g/cm3 water). After bleeding body and internal organs weight were measured and their ratio were calculated. Anatomo-pathological lesions, histopathological and ultrastructural examinations with the use of transmission and scanning microscope, serum cobalt-activated acylase (AA-Co) activity and urine arylsulphatase (ASA) activity were performed. It was found used preparation had some anti-tumors effect of mice with lymphatic leukemia. Serum cobalt-activated acylase and urine arylsulphatase of AKR mice for observation on disease development and dynamics of this process. In the ultrastructural picture changes of lymphatic cells after outside removal of degradated complexes of intracell membranes was observed.
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PMID:[Morphological and biochemical studies of the effect of the peat-derived preparation PF-290/II/2 on the development of natural lymphatic leukemia in mice]. 348 32

1-beta-D-Arabinofuranosyl-2-amino-1,4(2H)-4-iminopyrimidine (ara-AIPy), a new deaminase-resistant analog of cytarabine, exhibited extremely potent antitumor activity against P388 leukemia [400 mg/kg on Days 1-5; increase in life span (ILS), 211%] and significant inhibition against Lewis lung carcinoma (inhibition of tumor weight, 68%) and mammary adenocarcinoma 755 (inhibition of tumor weight, 82%). Schedule-dependency studies indicate that this drug, unlike cytarabine, was effective irrespective of its treatment schedules. The drug exhibited therapeutic efficacy against established P388 tumor transplants (400 mg/kg on Days 3-7; ILS, 131%) and inhibited the tumor growth effectively even when administered as a single dose on Day 1 by both ip (2000 mg/kg; ILS, 150%) and iv (500 mg/kg; ILS, 68%) routes. Ara-AIPy was most effective when administered on Days 1, 3, 5, 7, and 9 after tumor transplantation (400 mg/kg; ILS, 210%, with 50% of animals 60-day survivors). Ara-AIPy inhibited the growth of L1210 leukemia when both the tumor transplantation and the drug treatment were administered by iv route (500 mg/kg on Days 1, 5, and 9; ILS, 181%). The routes of administration of ara-AIPy experiments showed that the drug was effective by both ip and iv routes of administration; however, better therapeutic values were obtained by ip schedules. These studies demonstrate that ara-AIPy exhibits highly significant and broad-spectrum antitumor activity against a variety of experimental animal tumor models and suggest a possible future role for this drug in the treatment of human neoplasia.
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PMID:Evaluation of antitumor activity of 1-beta-D-arabinofuranosyl-2-amino-1,4(2H)-4-iminopyrimidine in murine tumors. 356 67

Two patients with relapsed acute lymphoblastic leukaemia of thymic phenotype (Thy-ALL) resistant to all conventional chemotherapy achieved complete remission when treated with 2'-deoxycoformycin, a selectively lymphocytotoxic compound that acts by inhibition of the enzyme adenosine deaminase. These observations show that malignant thymocytes are dependent on adenosine-deaminase activity and suggest that it may be possible to use deoxycoformycin in other patients with Thy-ALL to induce remission or to kill Thy-ALL blasts in bone marrow harvested before autologous bone-marrow transplantation, leaving normal haemopoietic stem cells intact.
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PMID:Remission induction with adenosine-deaminase inhibitor 2'-deoxycoformycin in Thy-lymphoblastic leukaemia. 610 39

2-Chlorodeoxyadenosine (CdA), an adenosine-deaminase-resistant purine deoxynucleoside, is markedly toxic toward human T-lymphoblastoid cell lines in vitro and is an effective agent against L1210 leukemia in vivo. The present studies have examined the toxicity, and in some cases, metabolism, of CdA in (1) multiple established human cell lines of varying phenotype, (2) leukemia and lymphoma cells taken directly from patients, (3) normal bone marrow cells, and (4) normal peripheral blood lymphocytes. Nanomolar concentrations of CdA blocked the proliferation of lymphoblastoid cell lines with a high ratio of deoxycytidine kinase to deoxynucleotidase. The drug had virtually no effect on the growth of cell lines derived from solid tissues. The CdA inhibited the spontaneous uptake of tritiated thymidine by many T and non-T, non-B acute lymphoblastic leukemia cell specimens at concentrations less than or equal to 5 nM. The same concentrations did not impair either thymidine uptake or granulocyte-monocyte colony formation by normal bone marrow cells. In common with deoxyadenosine, but unlike several other agents affecting purine and purine metabolism, CdA was lethal to resting normal T lymphocytes and to slowly dividing malignant T cells. In both resting and proliferating lymphocytes, the CdA was phosphorylated by deoxycytidine kinase and entered a rapidly turning over nucleotide pool. Dividing lymphocytes also incorporated abundant CdA into DNA. The selective toxicity of CdA toward both dividing and resting lymphocytes may render the drug useful as an immunosuppressive or antileukemic agent.
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PMID:Specific toxicity of 2-chlorodeoxyadenosine toward resting and proliferating human lymphocytes. 613 5

Various 2'-azido- and 2'-aminoarabinofuranosyl purine and pyrimidine nucleosides have been synthesized. Among these, the derivatives of cytosine and of adenine inhibit the growth of some tumor cell lines in vitro and in vivo. 2'-Azidoarabinofuranosyl cytosine also interferes with the replication of herpes simplex virus types I and II. Whereas 2'-azidoara-C is resistant to deamination by a partially purified CdR deaminase from KB cells, the adenine derivatives are substrates for aminohydrolases partially purified from calf and mouse intestines. Both azido- and aminoara-C are phosphorylated by partially purified CdR kinases from leukemia L1210 and from human AML blast cells. The accumulated data encourage exploration of the clinical utility of the more potent of these analogues.
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PMID:Synthesis, biologic effects, and biochemical properties of some 2'-azido- and 2'-amino-2'-deoxyarabinofuranosyl pyrimidines and purines. 744 52


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