Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Disulfiram (DSF) and its metabolites, diethyldithiocarbamic acid (DDC) and diethylamine (DEA), were studied as pretreatments in combination with the alkylating agent nitrogen mustard (HN2) on the cytotoxicity of HN2 against both leukemia cells and normal hematopoietic stem cells. Both time intervals and dose relationships were examined. DSF showed a substantial potentiation of HN2 cytotoxicity against murine AKR leukemia cell spleen colony-forming units (LCFU) when given i.p. between 15 to 30 min prior to HN2 i.v. treatment. For 3 mg DSF/mouse pretreatment, leukemia LCFU survival was about 10(-6) whereas it was about 10(-2) for HN2 alone. The extent of this potentiation decreased as the time between treatments increased. Significant potentiation was noted even when a low dose of DSF (0.25 mg/mouse) was administered 15 min before HN2. However, DSF had little if any effect on the modulation of HN2 cytotoxicity to normal hematopoietic cell spleen colony-forming units (NCFU). DDC showed an increasing potentiation of HN2 cytotoxicity against LCFU when given i.p. prior to HN2 i.v. treatment. The maximum effect was noted between 2 and 4 h with a surviving fraction for LCFU between 10(-5) and 10(-6) for 20 mg/mouse DDC pretreatment. The extent of this effect then decreased as the time interval increased beyond 4 h, but it was still significant for the 24-h interval. This pronounced potentiation effect was dose dependent for DDC. The compound exhibited a protective effect against HN2 cytotoxicity to NCFU when given 15 min before HN2. This protection decreased with increased time interval. DEA (20 mg/mouse) did not show a significant potentiation of HN2 cytotoxicity against LCFU when administered i.p. prior to HN2. Also, DEA did not show any significant protection of NCFU.
 ...
PMID:Potentiation of nitrogen mustard cytotoxicity by disulfiram, diethyldithiocarbamic acid, and diethylamine in mice. 255 50

The v-myc oncogenes of chicken retroviruses (including MC29) bear point mutations relative to chicken c-myc. These mutations result in several amino acid differences in the encoded proteins. We have used recombinant murine retroviruses containing various myc alleles to analyse the myelomonocytic transforming potential of the myc oncogene. The myc alleles used were MC29 v-myc, chicken c-myc, chimeric genes combining 5' sections of v- or c-myc with 3' sections of c- or v-myc, and mouse c-myc. The same retroviral vector (based on the genome of Moloney leukemia virus) was used for each allele and the genes were translated from genomic message. By infecting the primary mouse tissues, bone marrow, peritoneal-derived macrophages and mixed embryonic tissue with the recombinant viruses, variation was found in the transforming efficacy of these alleles: v-myc was most effective, followed by the two chimeric genes, whereas c-myc (chicken or mouse) was least effective in eliciting myelomonocytic transformation. Viral gag sequences were not necessary for this transformation. In each case, the transformed monocytes were growth factor-dependent and non-immortal. However, v-myc transformed monocytes (though not monocytes transformed by other myc alleles) were able to progress to an immortal, growth factor-independent phenotype. Our results indicate that v-myc is far more effective than c-myc in eliciting myelomonocytic transformation; that this is due to combinatorial effects of 5' and 3' mutations in the v-myc gene; and that secondary events in addition to these mutations are required for transformation of myelomonocytic cells to an immortal, tumorigenic phenotype.
 ...
PMID:Transformation of murine myelomonocytic cells by myc: point mutations in v-myc contribute synergistically to transforming potential. 264 46

Alkaline elution was done on a variety of cells following cyclophosphamide (CY) treatment in vivo. Cells used were L1210 leukemia, normal mouse bone marrow, and peripheral blood cells obtained from a patient with chronic lymphatic leukemia (CLL). Endpoints used were determination of single strand breaks, DNA-DNA interstrand and DNA-protein cross-links. After treatment of mice with CY (4 mg/mouse), low levels of single strand breaks were observed in both L1210 leukemia and CDF1 normal bone marrow. When a patient with CLL was treated with CY (750 mg/m2), no evidence of single strand breaks could be demonstrated. Maximum levels of DNA-DNA interstrand cross-links were observed in mice 2 h after injection of CY for the L1210 leukemia cells [175 +/- 25 rad-equivalents (req)] and at 4 h for the CDF1 normal bone marrow cells (47 +/- 9 req). In human CLL, maximum levels were observed 12 h after injection of CY. Peak levels of DNA-DNA interstrand cross-links were approximately 4-fold lower in CDF1 normal bone marrow cells than in L1210 leukemia. The frequencies measured in human CLL cells were relatively low at any timepoint (mean at 12 h = 36 req). Maximum levels of DNA-protein cross-links were observed 4 h after injection of CY (4 mg/mouse) for both L1210 leukemia [123 req (mean)] and normal bone marrow cells [50 req (mean)]. DNA-protein cross-links were measurable in CLL at timepoints later than 4 h after the start of injection of CY. In order to obtain equitoxicity between L1210 leukemia and CDF1 normal bone marrow cells, about 18-fold higher doses of CY had to be given than in the case of the normal bone marrow cells. In contrast, only 4-fold higher doses had to be given to the normal bone marrow to obtain equivalent peak levels of DNA-DNA interstrand cross-links.
 ...
PMID:In vivo DNA cross-linking by cyclophosphamide: comparison of human chronic lymphatic leukemia cells with mouse L1210 leukemia and normal bone marrow cells. 273 Nov 67

When a murine leukemia L1210-specific Lyt-2+ T cell clone, K7L, was injected i.p. into CD2F1 mice together with L1210, the normal growth of L1210 in the peritoneal cavity of the mice at the early stage (days 0 to 5) was strongly inhibited, but L1210 grew progressively at the middle-stage (days 5 to 10), and then was rejected at the late stage (days 10 to 20). The mice thus survived for long times (more than 60 days), whereas the normal control injected with L1210 alone died within 14 days. The L1210 that grew at the middle stage in mice initially inoculated with L1210 together with K7L was a K7L-insensitive (K7L-) variant. All of eight tumor clones established from L1210-K7L- by limiting dilution was insensitive to the antitumor activity of K7L, and this property of tumor clones was stable after repeated in vitro passage. The initial depression of the L1210 growth by K7L followed by growth and rejection of the variant L1210-K7L- by the host T cell activity was then found to prepare a strong, long-lasting (more than 3 mo) immunity to protect mice against the high-dose (10(7) cells per mouse) challenge of original L1210. Corresponding to this result, definite tumor (L1210)-specific cytotoxic T lymphocyte (CTL) activity against both variant and original L1210 targets was developed by antigen (L1210) restimulation in the culture of spleen cells from these mice, but was not increased to a detectable level before L1210-K7L- variant started to grow. It was suggested that the 1210-K7L- variant and the original L1210 should have the common tumor-specific antigen that was independent of the K7L-reactive antigen, and that original L1210, whose growth was retarded by K7L, primed the host with the common antigen to be enormously boosted by the subsequently growing L1210-K7L- variant.
 ...
PMID:Development of host-dependent high-grade tumor-specific immunity through a novel mechanism triggered by the Lyt-2+ tumor-specific T cell clone (K7L) that induces temporal growth of L1210 leukemia-K7L-variant. 295 38

An immunological focus assay using monoclonal antibodies on live adherent in vitro cell lines was employed to detect and isolate different types of murine leukemia viruses (MuLVs) from spleen and thymus cells of young (less than 1 month of age) AKR/J mice. In agreement with earlier studies, ecotropic viruses were detected from cells of both tissues in all mice tested, although only trace levels of ecotropic MuLV infectious centers were found with thymus cells from mice of this age. Polytropic MuLVs were not detected in mice less than 3 weeks of age; however, between the ages of 3 and 4 weeks, polytropic viruses were detectable in assays of spleen cells from 50% of the mice. No polytropic MuLVs were detected in assays of thymocytes from any mice of this age. Several polytropic MuLVs obtained from spleens of young mice were further characterized. All of the isolates were infectious for both mink and SC-1 (feral mouse) cells, and exhibited interference properties typical of polytropic MuLVs. However, none of the viruses induced obvious cytopathic effects (CPE) on mink cells. All of the viruses appeared antigenically similar with regard to their reactivities to a panel of 12 monoclonal antibodies directed at envelope antigens of polytropic MuLVs. RNase T1-resistant oligonucleotide analysis of a polytropic MuLV from a 26-day-old mouse indicated that its entire env gene was derived from nonecotropic sequences while the remainder of its genome was indistinguishable from the ecotropic parent. The isolate thus exhibited a genome structure typical of Class II polytropic MuLVs and is the first example of this type of MuLV isolated from AKR/J mice. Examination of polytropic MuLVs derived from the spleens and thymuses of 5- to 6-month-old mice indicated that only 2 of 10 isolates examined induced CPE on mink cells. Furthermore, most of the CPE-negative viruses isolated from spleen and thymus cells of these mice exhibited in vitro host ranges and antigenic reactivities similar to isolates from young mice, suggesting that this type of polytropic MuLV may originate in the spleen, subsequently spread to other tissues, and persist throughout the preleukemic period. The detection of polytropic viruses in a large proportion of very young mice is in contrast to previous studies which have not detected polytropic virus production in AKR mice less than 5 to 6 months of age.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Characterization of polytropic MuLVs from three-week-old AKR/J mice. 301 82

The effects of recombinant, macrophage-derived, murine tumor necrosis factor-alpha (TNF-alpha) on hematopoiesis in vivo has been examined in normal mice and in Friend virus (FV)-induced erythroleukemic mice. Intravenous (IV) administration of a single dose of recombinant murine TNF-alpha (10(5) U per mouse) significantly suppressed normal and leukemic late-stage erythropoiesis as measured by numbers of mature erythroid colony forming cells (CFU-E) in the bone marrow and spleen and by peripheral blood reticulocyte counts. In normal animals, the immature erythroid (BFU-E), macrophage (CFU-M), and granulocyte-macrophage (CFU-GM) compartments were significantly stimulated by TNF-alpha in both the bone marrow and the spleen. In the bone marrow of leukemic mice, the BFU-E, CFU-GM, and CFU-M progenitor cell compartments were also stimulated by treatment with the monokine. In the spleens of leukemic mice (the primary site of FV leukemia cell accumulation), relative numbers of BFU-E and CFU-GM were increased by TNF-alpha, while those of CFU-M were suppressed. TNF-alpha caused a rapid decrease in the markedly elevated spleen weights of progressively leukemic mice, and in multiple doses it caused complete clinical disease regression in a significant percentage of leukemic animals. The combination of TNF-alpha with interferon-gamma (IFN-gamma) increased the incidence of leukemia regression, compared with TNF-alpha alone. These results show that TNF-alpha exerts a suppressive influence on late-stage erythropoiesis in vivo and suggest that this effect might be exploited in the treatment of acute erythroleukemia, erythroid hyperplasias, and related diseases.
 ...
PMID:In vivo hematopoietic effects of tumor necrosis factor-alpha in normal and erythroleukemic mice: characterization and therapeutic applications. 319 71

The sensitivity of leukemia cells of AKR/J mice to subsequent lomustine [1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU)] exposure was found to vary with time following the ip administration of a single dose or multiple doses of amphotericin B (AmB) (0.5 mg/mouse/dose). Following 1 dose of AmB, leukemia cell sensitivity to CCNU, as measured by a spleen colony assay, reached a maximum by 24 hours with a tenfold increase in cell killing noted over cell killing with CCNU alone (0.15 mg/mouse). Two pretreatments with AmB separated by 24 hours led to a hundredfold increase in cell killing, whereas 4 pretreatments, each separated by 24 hours, gave more than a thousandfold increase in cytotoxicity by 8 hours, gave more than a thousandfold increase in cytotoxicity by 8 hours. Increasing the AmB dose, given as a single injection 24 hours before CCNU, resulted in increased potentiation of CCNU cytotoxicity, which reached a maximum at 0.5 mg/mouse. The kinetics of cell killing following either CCNU alone or the combination of AmB and CCNU were similar, although the extent of cell killing was greater with the combination. The AmB plasma pharmacokinetics for single doses showed a dose-dependent serum peak level and a half-life of about 24 hours for doses up to 1 mg/mouse. Nonlinearity was noted at the dose level of 2 mg/mouse because of saturation of absorption from the peritoneal cavity. These data are of importance for the optimal sequencing and dosing of these drugs for future clinical trials.
 ...
PMID:Schedule-dependent potentiation of lomustine cytotoxicity by amphotericin B in mice. 345 66

Encapsulation in liposomes of the antitumoral drug 2-methyl 9-hydroxyellipticinium and the consequences of its cytotoxicity in vitro on L1210 leukemia cells and on its antitumoral activity in vivo on leukemic mice inoculated with L1210 cells are described. Provided the drugs is dissolved in the buffer below its critical micelle concentration (10(-4) M), it can be encapsulated in lipid vesicles with a very good yield in the form of a very stable combination with the lipids. The in vitro experiments show that 2-CH3 9-OH-ellipticinium is less cytotoxic against L1210 cells when entrapped than when free in solution. The in vivo experiments on tumor-bearing mice show that encapsulation of the drug reduces its toxicity. Encapsulation maintains the antitumoral activity of the drug or increases it if the leukemia is delayed (10(4) cells injected per mouse instead of 10(5) cells per mouse).
 ...
PMID:Inhibition of tumor cell growth in vitro and in vivo by 2-methyl 9-hydroxyellipticinium entrapped within phospholipid vesicles. 376 91

The in vitro effect of adriamycin (ADR) and lonidamine alone and in combination, at 37 degrees C and 43 degrees C, was investigated on murine leukemia P388 sensitive (P388/S) and resistant (P388/ADR) to adriamycin. The sensitive and the resistant cells were exposed in vitro with and without the drugs for 1 h at 37 degrees C and 43 degrees C. These cells were inoculated ip (10(6) cells/mouse) into groups of BDF1 mice. Cytotoxic effect of the treatment was assessed on the basis of percentage increase in life span (% ILS) of these animals, compared to the animals receiving cells which did not receive any treatment but exposed only to 37 degrees C for 1 h. It was observed that exposure of P388/ADR cells to lonidamine or adriamycin alone at 43 degrees C for 1 h resulted in greater cell kill, thus enhancing the % ILS of the experimental animals receiving those cells, compared to that of mice receiving the cells exposed to the same drugs for 1 h at 37 degrees C. However, the combination of lonidamine (0.02 mM) and adriamycin (10 micrograms/ml) at 43 degrees C for 1 h showed more than a synergistic effect, resulting in a % ILS of 120. Similar results were seen in the case of P388/S; however, the observations pertaining to P388/ADR are encouraging, since the mode of treatment has reversed the acquired resistance of P388 leukemia cells to adriamycin.
 ...
PMID:Potentiation of adriamycin cytotoxicity in P388 murine leukemia sensitive and resistant to adriamycin by use of lonidamine and hyperthermia. 379 66

Antiviral and antileukaemic effects of the synthetic (2'-5')-oligoadenylate trimer [(2'-5')-ApApA] were demonstrated in BALB/c mice infected with Rauscher murine leukaemia virus (RMLV) by intraperitoneal (i.p.) treatment for 5-20 days (100 micrograms--1 mg daily doses) as evidenced by 72% suppression of viraemia and by decreased activity of serum reverse transcriptase levels. Electron microscopy revealed more than 95% inhibition of RMLV replication as compared to controls in transformed spleen cells from mice treated 5 times with 1 mg dose of (2'-5') ApApA. A significant and dose-dependent reduction of spleen weights of the RMLV-infected mice treated with (2'-5') ApApA was also observed. The antileukaemic effect of (2'-5-') ApApA was enhanced by simultaneous i.p. injection of amphotericin B (20 micrograms/mouse). In comparison to the effect of interferon (IFN) on RNA tumour viruses, our results suggest a higher antiviral activity of the synthetic (2'-5') ApApA oligonucleotide in suppressing RMLV replication in vivo.
 ...
PMID:Antiviral and anticellular effects of synthetic (2'-5')-oligoadenylate (A 2' p 5' A 2' p 5' A) in Rauscher murine leukaemia. 614 Aug 32


<< Previous 1 2 3 4 5 6 Next >>