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)

5-Fluorouracil (5-FU) is an effective antitumor agent used in treating various cancers. Because of its metabolism by intestinal and other cells, 5-FU has an inconsistent bioavailability that limits its oral use. 5-Fluoro-2-pyrimidione (5-FP), a 5-FU prodrug, was synthesized and found to be converted to 5-FU by aldehyde oxidase, an enzyme present in high concentrations in the livers of mice and humans but not in the gastrointestinal tract. Using BDF1 mice, the pharmacokinetics of 5-FP were studied and compared with those of 5-FU. The bioavailability of 5-FP given orally was 100% at a dosage of 25 mg/kg and 78% at a dosage of 50 mg/kg. The half-lives of both doses of 5-FP were at least 2-fold longer than the half-lives of the same doses of 5-FU, and the clearance rates of 5-FP were 3-fold slower. 5-FP was converted rapidly to 5-FU, in vivo. The resulting 5-FU was measured at a steady-state level of 40-70 microM in plasma, at a dosage of 25 mg/kg, that was sustained for at least 4 hr. Also, when given orally, 5-FP was shown to have potent activity against Colon 38 tumor cells and P388 leukemia cells in mice. The therapeutic index of 5-FP was similar to that of 5-FU in these mouse tumor models. The potential clinical use of 5-FP as a prodrug of 5-FU should be considered.
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PMID:5-Fluoro-2-pyrimidinone, a liver aldehyde oxidase-activated prodrug of 5-fluorouracil. 774 92

Stroma-dependent long-term bone marrow cultures (LTBMC) assay the ability of primitive haematopoietic stem cells (HSC) for long-term production of clonable progenitors. We have developed a limiting dilution type LTBMC assay allowing frequency analysis of transiently repopulating HSC and long-term culture initiating cells (LTC-IC) without the necessity to replate large numbers of wells. Normal or 5-FU-treated Ficoll bone marrow cells (BMC), or BMCs sorted on CD34 or HLA-DR expression, or Rh123 retention, (input range 40-70,000 CFU-GM/BFU-E/10(5) cells) were plated at limiting dilution on unirradiated adherent layers formed by a novel murine preadipose cell line (FBMD-1). The percentage of wells with at least one phase-dark haematopoietic clone (cobblestone area, CA) beneath the stromal layer was weekly determined for at least 8 weeks, and CA-forming cell (CAFC) frequencies were calculated using Poisson statistics. Parallel LTBMCs of the same samples were weekly assessed for supernate CFU-GM/BFU-E production. Weekly addition of rhIL-3 with rhG-CSF supported a high average clonogenic output per CA and dramatically increased CA size, but did not significantly alter the apparent CAFC frequency. The generation of CFU-GM per CA was constant over a period of 6 weeks with weekly means of eight normal BM samples, ranging between 5-16. At week 6 the mean CAFC frequency was 29 (1 SEM, 8.8)/10(5). Early appearing CAFC were highly sensitive to 5-FU, and were contained over the full Rh123 and HLA-DR fluorescence profile of CD34pos cells, whereas CAFC week 5-8 were predominantly contained in the CD34pos Rh123dull HLA-DRlow fraction in agreement with previously reported LTC-IC characteristics. In conclusion, the CAFC assay enumerates LTC-IC using a direct visual endpoint and allows study of LTC-IC heterogeneity with respect to progenitor cell generation per stem cell clone in various haematologic diseases.
Leukemia 1994 Jul
PMID:Frequency analysis of human primitive haematopoietic stem cell subsets using a cobblestone area forming cell assay. 803 1

Since radiotherapy or chemotherapy alone may be ineffective, they are more and more often combined. In this in vitro studies the effects of the chronology of the treatments and of the time interval between them are evaluated. In murine leukaemia L1210 cells and in murine mammary adenocarcinoma Ca755 cells the highest efficacy, i.e. the lowest survival fraction, was observed when radiotherapy was administered 6 h before Fluorouracil (FU). To mimic treatment in man, a daily combined treatment was also tested. Under these circumstances, the chronology of the treatments and the time interval between them had different consequences, the highest efficacy being noticed when both treatments were given at the same time.
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PMID:Chronology of combined chemotherapy (5FU) and radiotherapy. I. In vitro study. 829 31

The present investigation reports on the efficacy of 5-FU encapsulated in liposomes for the treatment of leukemia using a murine model of gamma radiation-induced transplantable leukemia in ICRC strain of mice. Multi-lamellar vesicles (MLVs) or large unilamellar vesicles (REVs) prepared using phosphatidyl choline and cholesterol in a molar ratio of 8:2 for neutral and 7:2:1 for charged vesicles were administered as a single i.p. dose in mice. 5-FU encapsulated in MLVs at a concentration of 0.6-2.5 mg/kg had no effect, whereas REVs at a single i.p. dose of 9 mg/kg increased survival of leukemic mice with T/C = 138%, decreased peripheral blood count and considerably reduced infiltration of leukemic cells in different tissues (supported by histopathology) as compared to 60 mg/kg of free drug (LD10 = 70 mg/kg).
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PMID:Treatment of gamma radiation-induced transplanted leukemia in ICRC mice by liposomally encapsulated 5-fluoro uracil. 832 42

We have examined the use of the LDH (lactate dehydrogenase) assay for chemosensitivity testing in established and primary cultures of sarcoma, leukaemia and ovarian cancer in parallel with the MTT assay. The method we describe is rapid, sensitive and ideal for 96-well plate assays using adherent or suspension cultures. Excellent agreement between the two methods was observed (r = 0.936) using a variety of antitumour agents, with some notable exceptions. In the Bax (human synovial sarcoma) cell line MTT colour production by control cells was very low, thus MTT-->formazan production could not be relied upon as a definitive end point equating with cell number. In contrast, colour production of control cells using the LDH assay was significantly greater and all cultures tested were suitable for titration of chemosensitivity. There was a discrepancy between IC50 values obtained either by cell counting or MTT in the HTB88 (human leiomyosarcoma) line treated with 5-FU (59.9 microM vs > 200 microM, respectively). However, cell counting agreed well with the LDH assay (IC50 47.3 microM). Whilst the MTT assay remains a reliable method for chemosensitivity testing, the LDH assay may prove more appropriate in certain experimental settings.
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PMID:Chemosensitivity testing of fresh and continuous tumor cell cultures using lactate dehydrogenase. 906 57

Vesnarinone (3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2(1H)- quinolinone), a quinolinone derivative, is an orally active inotropic agent used in Japan for the treatment of chronic heart failure. Recently, it has been reported that vesnarinone induces differentiation and apoptosis in certain types of leukaemia and solid tumour cells, and exhibits antitumour effect on several tumours xenografted in nude mice. In the present study, we examined the antitumour effect of vesnarinone in combination with radiation and conventional anticancer agents in nude mice xenografted with human gastric carcinoma, a poorly-differentiated adenocarcinoma, MKN-45 cell line which has a wild-type p53 gene. Vesnarinone treatment combined with radiation resulted in a higher antitumour activity compared with a single treatment with either vesnarinone or radiation alone. Further, vesnarinone treatment together with radiation and conventional anticancer agents including 5-FU and picibanil (an immunopotentiator) produced the highest antitumour effect compared with any other treatment. Additionally, the combination treatment induced marked differentiation and apoptosis of the tumour cells and an increase in the expression of p53 gene in the treated tumour cells. The results suggest that vesnarinone, in combination with radiation and the conventional antitumour agents, may be of clinical interest for treatment of certain types of gastric tumours.
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PMID:Enhancement of anticancer effects of radiation and conventional anticancer agents by a quinolinone derivative, vesnarinone: studies on human gastric cancer tissue xenografts in nude mice. 956 10

The current standard of care for patients with stage T3 rectal cancer is adjuvant combined-modality treatment with radiation and fluorouracil (5-FU)-based chemotherapy. Although data from randomized phase III trials comparing preoperative and postoperative combined-modality therapy are lacking, preoperative therapy is an option in T3 disease and can be considered the standard of care for T4 disease. Given its effects in reducing systemic disease in stage IV rectal cancer and its potential for radiosensitization of target tumors, oxaliplatin (Eloxatin), a new cytotoxic agent from the diaminocyclohexane platinum family, is being evaluated in preoperative combined-modality regimens in a Cancer and Leukemia Group B (CALGB) phase I/II study (protocol 89901) in T4 disease and an Eastern Cooperative Group (ECOG) phase I study (E-1297) in locally advanced T3 or T4 disease.
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PMID:Rectal cancer: integrating oxaliplatin into chemoradiation studies. 1120 62

In this study we investigated the efficacy of a combination of IL-12 and 5-FU, a chemotherapeutic exerting several immunomodulatory effects, in murine L1210 leukemia. Mice inoculated with 1 x 10(5) leukemia cells were treated with a single dose of 5-FU (50 mg/kg) and seven daily doses of IL-12 (100 ng/dose), and were observed for survival. Treatment with IL-12 or 5-FU given alone produced moderate anti-leukemic effects. However, combination of both drugs resulted in a significant prolongation of mouse survival time. Importantly, there were 70% of long-term (>60 days) survivors among mice treated with both agents simultaneously. Moreover, we observed 100% of long-term survivors when mice were treated with a minimally increased dose of IL-12 (170 ng) in combination with 5-FU (50 mg/kg). The antileukemic effects were completely abrogated in scid/scid mice and in mice depleted of peritoneal macrophages and significantly decreased after administration of anti-CD3+, anti-CD4+ or anti-CD8+ monoclonal antibodies. Administration of anti-NK1.1 antibodies did not decrease the antileukemic effects indicating that NK cells are not important effectors of this treatment regimen. Collectively, these results indicate that the combination of IL-12 and 5-FU is inducing strong antileukemic responses that are dependent on the presence and activity of macrophages and T lymphocytes and warrant further studies of combined chemo-immunotherapy with IL-12.
Leukemia 2001 Apr
PMID:Potentiatied antitumor effectiveness of combined chemo-immunotherapy with interleukin-12 and 5-fluorouracil of L1210 leukemia in vivo. 1136 64

E7070 (N-(3-Chloro-7-indolyl)-1,4-benzenedisulphonamide) was selected from our sulphonamide compound collections via antitumour screening and flow cytometric analysis. Following treatment with E7070, the cell cycle progression of P388 murine leukaemia cells was disturbed in the G1 phase. The cell-killing effect on human colon cancer HCT116 cells was found to be time-dependent. In the panel of 42 human tumour cell lines, E7070 showed an antitumour spectrum that was distinct from those of other anticancer drugs used in clinic. Animal tests using human tumour xenograft models demonstrated that E7070 could cause not only tumour growth suppression, but also tumour regression in three of five colorectal and two of two lung cancers. In the HCT116 xenograft model, E7070 was shown to be superior to 5-FU, MMC and CPT-11 (irinotecan). Furthermore, complete regression of advanced LX-1 tumours was observed in 80% of E7070-treated mice. All of these observations have promoted this drug to clinical evaluation.
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PMID:E7070, a novel sulphonamide agent with potent antitumour activity in vitro and in vivo. 1167 18

XK-469 is advancing to Phase I clinical trials. Preclinical studies were carried out to assist in clinical applications. DOSE-SCHEDULE ROUTE TESTING: Single dose i.v. treatment with XK-469 produced lethality (LD20 to LD100) above 142 mg/kg. Optimum treatment required total dosages of 350 to 600 mg/kg. Furthermore, high individual i.v. dosages (100 to 142 mg/kg) were poorly tolerated, producing substantial weight loss (8 to 18% of body weight), poor appearance, and slow recovery (8 to 12 days). A 1-hour infusion of dosages more than 140 mg/kg, or BID injections 6 hrs apart, did not reduce lethality. However, lower individual dosages of 40 to 50 mg/kg/injection i.v. were well tolerated and could be given daily to reach an optimum total dose with minimal toxicities. Likewise, 75 mg/kg/injection i.v. could be used every other day to reach optimal treatment. The necropsy profiles of deaths from toxic dosages were essentially identical regardless of schedule (deaths 4 to 7 days post treatment). The profiles were: paralytic ileus or gastroparesis; GI epithelial damage; and marrow toxicity. Interestingly, the key lethal events were rapidly reversible and simple to overcome with lower dosages given daily or every other day. Based on these results, the high dose, Q21 day schedule should be avoided in clinical applications. Instead, a split dose regimen is recommended (e.g., daily, every other day, or twice weekly). XK-469 was also well tolerated by the oral route, requiring 35% higher dosages p.o. to reach the same efficacy and toxicity as produced i.v.. CROSS-RESISTANCE STUDIES: XK-469 resistance was produced by optimum treatments of i.v. implanted L1210 leukemia over seven passage generations. This leukemia subline (L1210/XK469) had reduced sensitivity to VP-16 (with a 4.0 log kill in i.v. implanted L1210/XK469 compared to an 8.0 log kill against i.v. implanted L1210/0). It also had a reduction in the sensitivity to 5-FU (with a 2.0 log kill in the implanted L1210/XK469 compared to a 4.0 log kill against i.v. implanted L1210/0). Other agents were approximately as active against the resistant tumor, including: Ara-C, Gemzar, Cytoxan, BCNU, DTIC, and CisDDPT. No case of collateral sensitivity was observed; i.e., no agent was markedly more active against the resistant subline L1210/XK-469 than against the parent tumor in mice.
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PMID:Preclinical efficacy evaluations of XK-469: dose schedule, route and cross-resistance behavior in tumor bearing mice. 1200 90


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