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)

Pyrazine diazohydroxide (sodium salt, NSC 361456; PZDH) is a new antitumor drug with relatively broad activity in initial evaluations against murine leukemias, solid tumors, and two human tumor xenografts in vivo. The present studies were designed to address questions about PZDH activity on different treatment schedules, its activity against metastases, and the extent of its cross-resistance with established drugs. Human LOX amelanotic melanoma xenografts in athymic mice were used to explore schedule dependence and activity against natural metastases, and a series of drug-resistant murine leukemias provided an in vivo cross-resistance profile. Single-dose treatment and prolonged treatment provided equivalent therapeutic responses to PZDH by both the i.p. and i.v. routes in the i.p. LOX model. A s.c. LOX model resulting in spontaneous pulmonary metastases was adapted for bioassay and quantitation of the numbers of LOX cells killed by PZDH among both primary and metastatic cell populations. It was demonstrated that PZDH afforded about 2-log10 orders of magnitude greater cell kill among pulmonary metastases than against primary s.c. LOX tumors in the same mouse. Murine leukemias resistant to doxorubicin (ADR), vincristine (VCR), cisplatin (DDPt), methotrexate (MTX), N,N'-bis(2-chloroethyl)-N-nitrosourea (BCNU), and cyclophosphamide (CPA) were not cross-resistant to PZDH. However, both P388 and L1210 leukemia sublines resistant to melphalan (L-PAM) were cross-resistant to PZDH, suggesting that patients previously treated with L-PAM might have less likelihood of response to PZDH than those who had had no opportunity to develop L-PAM resistance. Although these observations should not be applied to clinical studies without due caution, they support clinical evaluation of PZDH as well as continued investigation of its molecular pharmacology.
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PMID:Schedule dependence, activity against natural metastases, and cross-resistance of pyrazine diazohydroxide (sodium salt, NSC 361456) in preclinical models in vivo. 231 Nov 70

Three cases of pulmonary atypical mycobacteriosis (AM) were reported. Two cases were associated with lung cancer in which the diagnosis of malignancy was difficult and delayed by the coexistence of AM. The third was a case of adult T-cell leukemia (ATL) which manifested during the course of AM. In case 1 (73 years, male) and case 2 (86 years, male), chest roentgenogram abnormalities as well as clinical symptoms were considered to be caused by mycobacteriosis because of positive smear of acid-fast bacilli in sputa on admission. Therefore it took four months and three months respectively for final diagnosis of lung cancer. The autopsy of case 1 revealed a poorly differentiated adenocarcinoma with coexisting foci of squamous cell carcinoma in right lower lung, and granulomatous inflammations with caseating necroses in right mid and lower lungs. M. avium complex was cultured from sputum on admission, and also a high titer of HTLV-I antibody was demonstrated. In case 2 malignant cells were detected in sputa (class V), however his general condition did not allow an aggressive anticancer chemotherapy and he died of malignancy with complication of thromboangiitis obliterans on right lower leg. Case 3 was a 76-year-old male who had been diagnosed as lung AM for more than two years. His chest radiography showed bilateral infiltrative shadows with frequent positive cultures of M. avium complex (more than 100 colonies) from sputum. A generalized lymphadenopathy including right hilar lymph node on chest X-ray film was followed by the presence of atypical lymphocytes in peripheral blood and the elevation of HTLV-I antibody in serum. Four months later he died with hypercalcemia and renal failure in spite of chemotherapy (CPM + VCR + ADR + PLS). The above cases suggest that AM as well as tuberculosis should be considered when pulmonary infiltrates were observed in malignant patients, especially in patients with retrovirus infections.
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PMID:[Three cases of pulmonary atypical mycobacteriosis associated with lung cancer and adult T-cell leukemia]. 237 33

Pyrindamycins A(1) and B(2) exhibited stronger cytotoxic activities than doxorubicin towards murine and human tumor cell lines and especially towards doxorubicin-resistant cells. Pyrindamycins A and B were also active in vivo against P388/ADR, a multidrug-resistant tumor cell line. Intracellular accumulation of pyrindamycins A and B in P388/ADR was the same as in P388. These antibiotics strongly inhibited DNA synthesis compared with RNA or protein synthesis. They showed significant therapeutic effects towards murine leukemia, but not to solid tumors.
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PMID:Antitumor activity of pyrindamycins A and B. 253 Nov 36

Accumulation of the dye rhodamine 123 was characterized by fluorescence in murine leukemia P388 cells and the Adriamycin-resistant subline, P388/ADR. Dye uptake by P388 cells was a slow, temperature-sensitive process, and involved binding at relatively hydrophobic and heterogeneous loci. Dye uptake by P388/ADR cells was temperature-insensitive, a steady state was quickly achieved, and the fluorescence emission spectrum suggested a relatively hydrophilic dye-binding site. Treatment of P388/ADR cells with verapamil resulted in enhanced accumulation of dye at hydrophobic loci. The fluorescence studies suggest that this dye may not reach the cytoplasm of P388/ADR cells, a result which may have implications with regard to the mechanism of multidrug resistance.
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PMID:Exploring multidrug resistance using rhodamine 123. 263 27

To improve the ability of flow cytometry to detect multidrug-resistant cells, we studied the extent to which cell volume heterogeneity accounts for the variance of intracellular daunorubicin (DNR) content. For P388 murine or HL-60 human leukemia cells exposed to DNR (1 micrograms/ml, 60 min), log intracellular DNR content varied in direct proportion to log cell volume measured by flow cytometry, with a correlation coefficient of .9. This relationship was confirmed by cell sorting based on intracellular DNR content with subsequent volume determination of the sorted cells. Normalization of intracellular DNR content for cell volume (thus obtaining intracellular DNR concentration) was accomplished by subtracting log cell volume from log intracellular DNR content for each cell. This resulted in a 34% decrease (range 23-58%) in standard deviation compared to DNR content measurements without volume normalization for all cell types tested. Following exposure to DNR (as above), intracellular DNR content of drug-sensitive P388 or HL-60 cells measured by flow cytometry was 12- and 8-fold greater than that of the multidrug-resistant sublines P388/ADR and HL-60/AR, respectively. However, because of the variance of intracellular DNR content, the predictive value of flow-cytometric determination of intracellular DNR content as a discriminant assay for detecting the frequency of drug-resistant cells in a mixed population was acceptable only when the frequency of resistant cells in the population exceeded 10%. In contrast, volume normalization of intracellular DNR content enhanced the ability of the flow-cytometric assay to discriminate resistant cells by 10-fold for P388 cells and 100-fold for HL-60 cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Improvement of flow-cytometric detection of multidrug-resistant cells by cell-volume normalization of intracellular daunorubicin content. 271 7

The combined effect of cisplatin (CDDP) with various types of antitumor drugs was examined in P 388 leukemia in vivo. Three representative drugs were chosen from every group of alkylating agents, antitumor antibiotics, antimetabolites, and plant originated drugs. According to their dependency on administration schedules, the dose-dependent and time-dependent drugs were administered once, and daily 5 times, respectively, before and after the single administration of CDDP. In addition to these sequential combinations, simultaneous treatment with CDDP was examined for the drugs which were singly administered. The combined effect was assessed by comparing ILS (increase in life span) in a combined group with the sum of ILS's of each of the 2 single-treatment groups. Synergistic effect was observed in the combination of CDDP with all drugs except MMC. Among them CYC, CQ, ACNU, ADR, PEP, ET, VCR, and VDS produced synergistic effect in any treatment schedules, irrespective of the combination sequences. In the cases of the combination with antimetabolites, the combined effect was depended on the treatment sequences; prior treatment of 5-FU, and posterior treatment of Ara-C and MTX to CDDP administration exhibited a synergistic effect, but the combination in reverse sequence remained almost additive.
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PMID:[Combined effect of CDDP with various types of antitumor drugs against P 388 leukemia]. 273 70

A series of 2-aminoalkyl-5-nitropyrazolo [3,4,5-kl]acridines (pyrazoloacridines) were tested in vitro against a panel of multidrug-resistant cell lines comprising Adriamycin-resistant P388 leukemia, B16 melanoma, and mammary adenocarcinoma 16c. This new class of anticancer agents, particularly the 9-substituted methoxy derivatives, exhibited significant activity against all of the lines tested. The degree of cross-resistance to these compounds ranged from zero to 8-fold in the 138-fold Adriamycin-resistant P388/ADR line and was greatly diminished in the B16/ADR and 16c/ADR lines. Selected pyrazoloacridines were subsequently tested in vivo against B16 and B16/ADR cells established as solid tumors from the tissue culture line and shown to retain a significant degree of Adriamycin resistance. Whereas the B16/ADR line exhibited 2 logs less net tumor-cell kill than the B16 parent in response to Adriamycin treatment, the resistant tumor was completely sensitive to the pyrazoloacridines tested and proved in some experiments to be collaterally sensitive. The favorable activity of the pyrazoloacridines against these Adriamycin-resistant tumor lines points to the potential efficacy of these compounds against multidrug-resistant tumors encountered clinically.
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PMID:Activity of the pyrazoloacridines against multidrug-resistant tumor cells. 275 1

Cultured murine leukemia P388 cell populations were derived from P388 cells resistant to vincristine (P388/VCR), adriamycin (P388/ADR), and 1-beta-D-arabinofuranosylcytosine (P388/ARA-C) that were developed in vivo and to the parental drug-sensitive cells (P388/O) that were passaged in vivo. The doubling times of the cultured cell populations (mean +/- SD) between cell densities of 5 x 10(4) and 1 x 10(6) cells/ml were 14.2 +/- 2 h (P388/O), 16.5 +/- 1.9 h (P388/VCR), 16.9 +/- 1.2 h (P388/ADR), and 15.0 +/- 1.4 h (P388/ARA-C). Exponentially proliferating cultured cell populations were exposed to selected homoharringtonine (HHT) concentrations for 24 h and the surviving cell fractions were determined by colony formation in semisolid medium. The results, based on differential sensitivity of the cell populations to HHT, indicated that cultured P388/VCR cells were cross-resistant to 0.018-1.8 micrograms/ml HHT, P388/ADR cells were cross-resistant to 0.058-1.8 micrograms/ml HHT, and P388/ARA-C cells were collaterally sensitive to 0.09-0.36 micrograms/ml HHT. The results with the cultured P388/VCR, P388/ADR, P388/ARA-C, and P388/O cell populations were confirmed in animal experiments. CD2F1 mice bearing intraperitoneal (i.p.) implants of 1 x 10(6) P388/VCR, P388/ADR, P388/ARA-C, or P388/O leukemia cells were given HHT i.p. qd on days 1-9 postimplantation. Optimal treatment (less than or equal to LD10) produced in vivo cell kills of 2 to 3 log10 units in P388/O and about 7 log10 units in P388/ARA-C, whereas P388/VCR and P388/ADR cells actually increased by 1-2 log10 units during treatment. The results of this study indicate that cross-resistance (P388/VCR and P388/ADR) or collateral sensitivity to HHT (P388/ARA-C) is a function of the cellular properties of the target tumor cell populations that is independent of host factors.
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PMID:Effect of homoharringtonine on the viability of murine leukemia P388 cells resistant to either adriamycin, vincristine, or 1-beta-D-arabinofuranosylcytosine. 292 72

Mice bearing the P388/S or P388/ADR (doxorubicin-resistant) leukemia were treated with menogaril or mitoxantrone. Both drugs were highly effective against P388/S but were ineffective against the doxorubicin-resistant subline, indicating cross-resistance. These observations may be of use in the design of clinical trials with these drugs.
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PMID:Cross-resistance of menogaril and mitoxantrone in a subline of P388 leukemia resistant to doxorubicin. 294 40

The mechanisms of acquired resistance to MTX were studied in P388 murine leukemia cell lines that were sensitive or resistant to ADR. The rate of MTX accumulation in ADR-sensitive cells that have acquired resistance to MTX was found to be lower than that measured in cells that were sensitive to both drugs. Furthermore, in contrast to drug-sensitive cells, in the ADR-sensitive MTX-resistant cells, most of the intracellular MTX (86.2%) was bound and MTX polyglutamation was not detected. The initial rate of MTX accumulation in cells that were resistant to both drugs was comparable to that measured in cells that were sensitive to both drugs or that were resistant only to ADR. However, in the cells that were resistant to both drugs, the rate of MTX accumulation was maintained at its initial level for a period that was considerably longer than that found in the other cell lines. After 3 h of exposure to MTX, the accumulation of MTX in cells that were resistant to both drugs was fourfold higher than that measured in cells that were sensitive to both drugs. Furthermore, while 65 to 70% of the intracellular MTX was free, in cells sensitive to both drugs, or resistant only to ADR, the corresponding value in cells that were resistant to both drugs was less than 1.5%, and a much lower proportion of the MTX was polyglutamated. The sensitivity to TMQ of ADR-sensitive, MTX-resistant cells was similar to that found in cells that were sensitive to ADR and MTX. However, ADR-resistant cells, sensitive or resistant to MTX, were markedly resistant to TMQ. The sensitivity of ADR-resistant MTX-sensitive cells to TMQ was restored by the presence of 10 microM verapamil. Such an effect was not observed in cells resistant to both drugs. It is suggested that P388 cells that have previously acquired resistance to ADR, when now selected by MTX, retain the MTX-transport system (in contrast to ADR-sensitive, MTX-resistant cells) and become resistant to MTX by increasing the activity of DHFR. The results obtained in ADR-resistant cells also suggested that resistance to TMQ was part of the multidrug resistance phenomenon.
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PMID:Mechanism of acquired resistance to methotrexate in P388 murine leukemia cells and in their doxorubicin-resistant subline. 297 48


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