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)

Ten patients with plasma cell leukaemia (PCL), out of 259 cases of multiple myeloma diagnosed in the Haematology Service of the University Hospital of Barcelona in the last 18 years, are presented. Of the 10 PCL cases, 5 were primary and 5 were secondary. Anaemia and thrombocytopenia, along with massive plasma cell infiltration of the bone marrow, were the most striking findings. Osteolytic lesions were present in 9 of the cases and liver involvement in two. Chemotherapy including vincristine and prednisone was administered to eight patients, associated to alkylating agents (melphalan and/or cyclophosphamide) in six of them. Four of these patients received also adriamycin and BCNU. Two objective responses were achieved, lasting for 10 and 3 months, the remaining six patients failed to respond. The median survival for all the PCL patients was less than one month (ranging between 0.2 and 14 months). None of the secondary PCL patients survived for 2 months after diagnosis. Infection (3 cases of septicaemia and 3 of pneumonia), renal failure (2 cases) and liver insufficiency (1 case) were the causes of death in the nine deceased patients. The therapeutic possibilities for this severe haemopathy are discussed.
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PMID:[Plasma cell leukemia. Study of 10 cases]. 265 43

Maloney murine leukemia virus-based, replication-defective retroviral vectors containing the neomycin resistance gene (neo) were developed to transfer the Escherichia coli ada gene coding for O6-alkylguanine-DNA alkyltransferase, into mammalian cells. To optimize gene transfer and expression, the following promoters were linked to ada: the Maloney murine leukemia virus promoter within the long-terminal repeat, the Rous sarcoma virus promoter, the thymidine kinase promoter, or the human phosphoglycerate kinase promoter. Sequences were transfected into the helper virus-free retroviral packaging psi-2 cell line. Recombinant retroviruses were tested in CCL-1 cells, which, like most murine tissues, have low levels of alkyltransferase and are sensitive to 1,3-bis(2-chloroethyl)nitrosourea (BCNU), and in NIH-3T3 cells, which are BCNU resistant and have high levels of alkyltransferase. Lines infected with each of the four retroviruses were selected for neo expression and found to have intact proviral integration and ada gene expression. Alkyltransferase activity was greatest with retrovirus containing the Rous sarcoma virus-ada gene; infected NIH-3T3 cells had up to 2300 units of alkyltransferase/mg of protein compared with 151 units/mg of protein in control cells, and infected CCL-1 cells had up to 1231 units/mg of protein compared with 33 units/mg of protein in control cells. CCL-1 cells expressing ada were more resistant to BCNU cytotoxicity than were controls. However, NIH-3T3 cells expressing ada were only slightly more resistant to BCNU than controls, possibly because most of the ada protein was cytoplasmic rather than nuclear as suggested by immunohistochemical stain. These studies establish a series of retroviruses containing the bacterial ada gene, which efficiently infect mammalian cells. ada expression increases nitrosourea resistance in cells with low mammalian alkyltransferase activity.
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PMID:Increase in nitrosourea resistance in mammalian cells by retrovirally mediated gene transfer of bacterial O6-alkylguanine-DNA alkyltransferase. 267 54

Seven nonsplenectomized patients with blastic CGL have received high dose BCNU chemotherapy followed by cryopreserved peripheral blood stem cells (PBSC). The PBSC obtained at diagnosis were stored in the vapor phase of liquid nitrogen in 10% dimethyl sulfoxide for 11-46 months prior to use. Patients received 2.9 X 10(8) (1.9-7.8) thawed washed mononuclear cells/kg over 30 minutes with minimal morbidity. One patient was not rendered pancytopenic and died with blastic leukemia at 4 months. One patient, previously treated with daily busulfan, died of progressive hepatic failure 2 months after high dose BCNU. Restoration of the chronic phase of CGL was observed in the remaining five patients. Peripheral blood counts returned to normal ranges after a median of 19 days. Median survival for all patients is 11 months. Cytogenetic studies revealed elimination of acquired aneuploid cell lines in four of seven patients with persistence of Ph1. We conclude that: 1) frozen PBSC retain their viability for up to 4 years after cryopreservation and 2) the use of autologous PBSC following ablative chemotherapy may be associated with both symptomatic and karyotypic improvement in patients with blastic CGL.
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PMID:Treatment of the blastic transformation of chronic granulocytic leukemia using high dose BCNU chemotherapy and cryopreserved autologous peripheral blood stem cells. 285 55

L1210 leukemia cells were treated in vitro with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and reovirus to determine their interactive effects on rejection of these tumor cells by mice. The cells were treated with BCNU at concentrations of 0, 3, or 10 microM, incubated for 48 h, then treated with reovirus at a multiplicity of infection of 0, 10, 30, or 100 for 2, 6, or 12 h. The survival of mice injected with cells treated with any amount of reovirus, regardless of BCNU treatment, was greater than that of mice injected with untreated cells. Exposure of the cells to reovirus for 6 or 12 h increased the survival of mice injected with these cells as compared with that of mice injected with cells exposed to reovirus for 2 h. Of the survivors, 76% were resistant to subsequent challenge with untreated L1210 cells. These results suggest that activities associated with reovirus replication may cause modifications of L1210 cells that enable them to induce an immune response, thus facilitating their rejection. A lack of correlation between differences in DNA synthesis (measured by 3H-thymidine uptake) by treated cells and the ability of those cells to kill recipient mice indicates that rejection of cells treated with reovirus or BCNU is not due to a decrease in their ability to proliferate or, presumably, to generate lethal tumors. The survival of mice injected with treated L1210 cell preparations containing as few as 2.9% reovirus-infected cells was enhanced to the same degree as that of mice injected with those containing as many as 14.6% infected cells, indicating that modification of only a minor component of the tumor cell population is sufficient to alter the ability of the cells to generate a lethal tumor.
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PMID:Rejection of reovirus-treated L1210 leukemia cells by mice. 294 8

Ten children who underwent allogeneic (n = 5) or autologous (n = 5) bone marrow transplantation (BMT) for chronic myelogenous leukaemia (n = 2), acute lymphoblastic leukaemia (n = 1), acute myelogenous leukaemia (n = 2), severe aplastic anaemia (n = 2), malignant histiocytosis (n = 1), neuroblastoma (n = 1) and teratoma (n = 1) were assessed for endocrinological function. Transplant preparative regimens consisted of high-dose cyclophosphamide, high-dose cyclophosphamide in combination with high-dose busulphan, high-dose melphalan as well as BACT (BCNU, cytarabine, cyclophosphamide and 6-thioguanine) chemotherapy. None of the patients received total body irradiation (TBI). Median survival following BMT was 37 months (range 7-115). Growth hormone deficiency was present in only one patient; none of the patients had abnormal thyroid or adrenocortical function. This is in contrast to previous reports in which growth hormone deficiency and abnormal thyroid and adrenocortical function occurred in a much higher percentage of patients after BMT conditioned with TBI.
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PMID:Endocrine function after bone marrow transplantation without the use of preparative total body irradiation. 304 94

Damages in secondary DNA structure and inactivation or activation of some repair enzymes such as DNA polymerases alpha and beta and poly(ADP-riboso)polymerase induced by 1-methyl-1-nitrosourea (MNU) and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) after administration of the drugs at therapeutic single doses to mice bearing parent L1210 leukemia cells (L1210/0) and MNU- and BCNU-resistant L1210 leukemia cells (L1210/MNU and L1210/BCNU) were studied. Damages in DNA structure of all three leukemia strains were investigated using centrifugation on alkaline or neutral sucrose gradients. More MNU-induced single-strand breaks (SSB) and alkali-labile lesions in L1210/0 and L1210/MNU cells were revealed in newly replicated DNA as compared with those in preexisting DNA. BCNU induced fewer SSB in newly replicated DNA of L1210/0 cells than MNU. The fastest repair of the damages in newly replicated DNA was detected in L1210/BCNU and especially in L1210/MNU cells as compared with L1210/0 cells. These results suggest that there are prone errors in the repair of DNA template as many SSB were revealed in the newly replicated DNA synthesized on the repaired DNA. Repair of DNA damages in L1210/BCNU and especially in L1210/MNU cells was accompanied by activation of DNA polymerases alpha and beta and poly(ADP-riboso)polymerase. It was shown that both DNA polymerases alpha and DNA polymerase beta were involved in the repair of damages induced by MNU and only DNA polymerase beta was involved in repair of damages induced by BCNU.
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PMID:In vivo DNA damage and resistance to 1-methyl-1-nitrosourea and 1,3-bis(2-chloroethyl)-1-nitrosourea in L1210 leukemia cells. 312 36

The etiology of alkylator-induced leukemia is obscure, but may be due in part to alternations in the bone marrow stromal microenvironment. Marrow extracellular matrix, including collagen, glycosaminoglycans/proteoglycans, and glycoproteins, may play a crucial role in the control of normal and abnormal hematopoiesis. Twenty-four hours after seeding, confluent human bone marrow stromal cell cultures were exposed for 3 h to 15 micrograms/ml of 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU), an alkylating agent with leukemogenic potential. On the eighth day of culture, [35S]sulfate was added and radiolabeled glycosaminoglycan(s) (GAGs) was harvested 24 h later. BCNU treatment resulted in a 104% increase of the radiolabel incorporation into cetylpyridinium chloride precipitable GAG. In addition, spectrophotometric measurement of total GAG in treated cells revealed a similar GAG increase. However, BCNU treatment did not alter compartmental GAG distribution or GAG species. Our results demonstrate a profound quantitative change in the production of important extracellular matrix components by bone marrow stromal cells after exposure to a nitrosourea. This increase may be a factor in microenvironmental alterations leading to bone marrow toxicity following alkylator exposure.
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PMID:BCNU-induced increase in sulfated glycosaminoglycan production by human bone marrow stromal cells. 313 51

A Mannich base namely 4-dimethylaminomethyl-1-phenyl-1-penten-3-one hydrochloride was shown to have far greater activity than 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) towards P388 leukemia cells in vitro. However, the compound was inactive in an in vivo P388 murine screen, and the object of this study was to discern molecular features which conferred in vivo activity. Mannich bases containing electron-attracting substituents in the aryl ring had in vivo potency in contrast to the analogs which had electron-donating groups in the ring. A number of hydrazones of the Mannich bases were prepared as potential prodrugs and did not enhance bioactivity. This observation was probably due to a lack of facile hydrolysis of the hydrazones to the corresponding Mannich bases in vivo since high resolution 1H NMR spectroscopy revealed that representative hydrazones either did not regenerate the ketones or produced them only in minute quantities at pH values normally encountered in living tissues.
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PMID:Evaluation of Mannich bases of styryl ketones and related hydrazones for activity against P388 leukemia. 322 38

The inactivation of the enzyme glutathione reductase by 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) was studied in exponentially growing murine leukemia cells. A 1-hr incubation with 1.6 +/- 0.2 microM BCNU resulted in a 50% inhibition of glutathione reductase, while 10 microM BCNU caused total inhibition of the enzyme. The time required for 50% inhibition of glutathione reductase by 10 microM BCNU was 7 min. The recovery of glutathione reductase activity was studied by incubating cells with 10 microM BCNU for 30 min to inhibit all glutathione reductase activity, washing the cells free of drug, and continuing the incubation in fresh medium. Fifty percent of the activity returned within 12 hr. Glutathione reductase activity recovered normally when cell growth and DNA synthesis were inhibited in the cells, but it failed to recover when protein synthesis was inhibited. Therefore, the inactivation of glutathione reductase appears irreversible, and the recovery of enzymatic activity is dependent on the synthesis of new protein. Continuous incubation with 19.8 +/- 0.4 microM BCNU resulted in a 50% inhibition of cell growth. A 1-hr incubation with 7.3 +/- 0.8 microM BCNU resulted in a 50% loss of viability as measured by a soft agar clonogenic assay. These experiments quantify the inhibition of glutathione reductase by BCNU and the recovery of enzyme activity in the context of the toxic effects of the compound. A clinically useful inhibitor of glutathione reductase will require a wider difference between the concentrations required for enzyme inhibition and cytotoxicity than BCNU provides.
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PMID:Characterization of the inhibition of glutathione reductase and the recovery of enzyme activity in exponentially growing murine leukemia (L1210) cells treated with 1,3-bis(2-chloroethyl)-1-nitrosourea. 340 Dec 59

A novel nitrosourea, 1-(2-chloroethyl)-3-[2-(dimethylaminosulfonyl) ethyl]-1-nitrosourea (TCNU) tauromustine, has been investigated in a broad anti-tumour screen and, in depth toxicology and initial pharmacokinetics carried out. TCNU and its two metabolites were found to exhibit equal or better oral efficacy than that of BCNU, CCNU, MeCCNU or chorozotocin against L1210 leukemia, Walker mammary carcinoma, Lewis Lung, Harding Passey melanoma and colon carcinoma C26. The toxicological profile of TCNU after acute and 3 months treatment was similar in mice and rats to that of CCNU, with the exception that, TCNU did not cause the chronic liver disturbances found for CCNU. In dogs treated for 6 weeks with TCNU leucopenia and thrombocytopenia were the major side effects. Parent TCNU was found in all dogs. The absorption was fast, the maximum level being reach after 25 mins and the mean absorption time was 22 mins. The mean half life was 16.1 mins after intravenous and 17.4 after oral administration. The combination of these factors make TCNU an interesting clinical candidate.
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PMID:Anti-tumour, toxicological and pharmacokinetic properties of a novel taurine-based nitrosourea (TCNU). 341 Jun 63


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