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)

A total of 125 children, who were diagnosed as having high-risk acute lymphoblastic leukemia (ALL), were treated with two consecutive protocols designated as AL851 (1985-1988) and ALHR88 (1988-1990). All patients received induction therapy consisting of vincristine (VCR), prednisolone (PSL), daunorubicin (DNR), and I-asparaginase (I-Asp). In the ALHR88 protocol, the patients whose blasts in the bone marrow (BM) were > or = 25% on day 14 of induction therapy and who were classified into T-cell type received additional cytosine arabinoside (AraC). After consolidation with intermediate-dose methotrexate (MTX), reinduction therapy including VCR, dexamethasone, and adriamycin followed by high-dose AraC was done for all patients. Intrathecal MTX and 24Gy of cranial irradiation were used to prevent central nervous system leukemia. A maintenance therapy consisting of 6-mercaptopurine, cyclophosphamide, MTX, DNR, VCR, and AraC was administered for 3 years after achieving a complete remission (CR). CR was achieved in 51/55 (92.7%) for AL851 and 68/70 (97.1%) for ALHR88. The 5-year event-free survival rates were 49.1 +/- 6.7% in AL851 and 62.5 +/- 6.1% in ALHR88. The factors related to a poor prognosis were a high initial leukocyte count of greater than 50 x 10(9)/L (P < 0.001), an L2 morphology of leukemic cells by FAB classification (P = 0.009), the chromosomal abnormality (P = 0.004) and high residual leukemic cells in BM (> or = 25%) on day 14 of induction therapy (P < 0.001). Taking these factors into consideration, more intensive protocols were started in 1990 for the patients with high-risk ALL.
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PMID:Treatment of high-risk acute lymphoblastic leukemia in children using the AL851 and ALHR88 protocols: a report from the Kyushu-Yamaguchi Children's Cancer Study Group in Japan. 749 7

A 70-year-old male was admitted to our hospital because of leukocytosis. The laboratory examination revealed leukocytosis (44,500/microliters) with blasts (99%) in the peripheral blood. Myeloperoxidase staining of the leukemia cells was negative, but the surface phenotype was CD13- and CD33-positive, and negative for all lymphoid antigens. Peroxidase staining using the electron microscope was positive. Thus, the patient was diagnosed as acute myeloblastic leukemia (M0), according to the FAB classification. Although the therapy regimens commonly used for ANLL were effective for some cases with M0, the regimens mainly for ALL were more effective for the others. Thus we cannot determine what is the most effective regimen for M0. Since the patient had many complications, he was treated with low-dose AraC instead of combination chemotherapy. After the beginning of treatment, he became febrile and we added G-CSF to Ara-C. One month later, the patient achieved complete remission without severe infection. After four courses of consolidation therapy, the patient was discharged. He has been maintained in remission for more than 3 years and 8 months with only 5-day oral administration of cytarabine ocfosfate every four weeks.
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PMID:[Continuation of complete remission by oral administration of cytarabine ocfosfate in a patient with M0, who achieved remission by small doses of cytosine arabinoside with G-CSF]. 753 75

We have investigated whether cytarabine (AraC) or decitabine (DAC) induce deficiency of deoxycytidine kinase (DCK) through different mutations of the dck gene, related to their distinct interference with DNA replication. Also, it is not known whether mutations of the dck gene are the result of selection of mutants or de novo induction. To address these issues, three subclones of a rat leukemic cell line (RCL/O), sensitive to cytotoxicity mediated by AraC and DAC, were exposed to gradually increasing concentrations (from 0.1 to 10 microM) of either AraC or DAC over a 140 days vs a 180 days period. During the course of resistance induction DCK activity was monitored. We found that all clones acquired irreversible cross-resistance, at marginally cytotoxic AraC or DAC concentrations of 0.1 to 0.4 times the IC50 for the parental clones. Furthermore, all resistant cell lines were DCK deficient and harbored different mutations in the dck gene. AraC induced both rearrangements and point mutations in the dck gene when administered over 140 days and 180 days, respectively. 140 days DAC induction yielded point mutations only. All point mutations detected were nonrandomly distributed within the dck coding region. SSCP analysis showed that in the majority of resistant clones more than one bandshift was present. The data suggest the presence of multiple resistant clones, originating from one sensitive clone and thus arguing against selection of mutants as a mechanism for the development of AraC and DAC resistance.
Leukemia 1995 Jun
PMID:De novo induced mutations in the deoxycytidine kinase (dck) gene in rat leukemic clonal cell lines confer resistance to cytarabine (AraC) and 5-aza-2'-deoxycytidine (DAC). 754 Oct 96

Haemostatic parameters were studied in 12 adult patients with acute myeloid leukaemia and acute lymphoblastic leukaemia in complete remission using high-dose cytosine arabinoside regiments together with with other drugs. Increased tissue plasminogen activator (t-PA:Ag) antigen 4 hours after AraC application (p < 0.05) as well as increased levels of plasminogen activator inhibitor activity (PAI) (p < 0.05) and fibrinopeptide A (FPA) antigen (p < 0.05) were observed on day 2. All patients during bone marrow aplasia suffered from infectious complications (7 from sepsis and 5 from fever of undetermined origin). During that period of infection the increased levels of FPA on day 21 (p < 0.05), PAI on days 15 and 21 (p < 0.05) and fibrinogen on day 21 (p < 0.05) as well as decreased values of antithrombin III (p < 0.05) on day 21 and protein C on day 15 (p < 0.05) were measured. t-PA:Ag, plasminogen, alpha 2 antiplasmin and fibrin(ogen) degradation products were within normal throughout infectious complications. None of the patients experienced clinically manifest thrombotic complication. Though the results demonstrate that changes found were not clinically important (even if they were statistically significant), and that haemostasis was compensated as well as that thrombosis was not serious problem, authors recommend routine haemostasis monitoring in acute leukaemia patients, especially at diagnosis, in association with chemotherapy and during infectious complications.
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PMID:[Hemostasis in patients with acute leukemia treated with high doses of cytosine-arabinoside: the effect of chemotherapy and infectious complications on hemostasis]. 781 98

The kinetics of hematological recovery after autologous marrow transplantation have been studied in 70 patients with acute leukemia (38 acute nonlymphoblastic leukemia [ANNL] and 32 acute lymphoblastic leukemia [ALL]). The incidence of graft failure in this group was 3.2%, and a persistent severe thrombocytopenia was observed in 24% of the cases. Variables influencing engraftment have been studied using univariate and multivariate statistical analysis. Analysis of the entire group showed a correlation between graft colony-forming unit granulocyte-macrophage (CFU-GM) content and granulocyte recovery (p < 0.001). Marrow purging was associated with a delayed engraftment (p < 0.001). In ANLL patients, we found that high cummulated AraC doses before marrow cryopreservation correlated with poor granulocyte recovery after marrow infusion (p < 0.002). Platelet recovery was essentially affected by age, with shorter thrombocytopenia periods in younger patients (p < 0.001). Finally, excluding autotransplants with purged marrows, ALL patients showed better platelet recoveries than ANLL patients (p < 0.005). These findings will be useful to evaluate the risk of delayed engraftment after autologous bone marrow transplantation (ABMT) in patients with acute leukemia.
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PMID:Hematological recovery after autologous bone marrow transplantation in acute leukemia: predictive factors. 792 68

The semiautomated fluorometric microculture cytotoxicity assay (FMCA), based on the measurement of fluorescence generated from cellular hydrolysis of fluorescein diacetate (FDA) to fluorescein in microtiter plates, was used for in vitro evaluation of Cladribine (2-chlorodeoxyadenosine, CdA) interactions with five standard antileukemic drugs: amsacrine (Am), etoposide (VP16), daunorubicin (Dnr), cytosine arabinoside (AraC), and mitoxantrone (Mit). Samples from 31 patients with acute myelocytic leukemia (AML) were tested with continuous drug exposure. A large heterogeneity with respect to cell kill was observed for all combinations tested. An additive model provided a significantly better fit of the data compared to the effect of the most active single agent of the combination (Dmax) only for CdA+AraC. When the frequency of additive and synergistic interactions were calculated according to the multiplicative concept for drug interactions, the highest frequencies were observed for CdA+AraC and CdA+Dnr. This interaction pattern was confirmed by isobologram analysis. Cross-resistance analysis revealed high correlations between CdA and AraC whereas the correlations were weaker between CdA and the other drugs. The highest frequency of synergistic interactions was obtained for AraC+CdA, despite their cross-resistance. Of the non-cross-resistant drugs tested, Dnr appears to be the most effective adjunct to CdA in terms of interactions at the cellular level.
Leukemia 1994 Oct
PMID:Interactions between cladribine (2-chlorodeoxyadenosine) and standard antileukemic drugs in primary cultures of human tumor cells from patients with acute myelocytic leukemia. 793 68

2-Chlorodeoxyadenosine (CdA) is a deaminase-resistant purine analogue which has shown clinical activity against various haematological tumours, and is currently undergoing phase II trials. In the present study, the semiautomated fluorometric microculture cytotoxicity assay (FMCA) was used for in vitro evaluation of CdA activity in cell suspensions from both haematological and solid tumours. A total of 133 samples from various diagnoses were successfully tested with continuous drug exposure. CdA showed high in vitro activity against samples from chronic and acute lymphocytic leukaemia and acute myelocytic leukaemia, but little or no response was observed in the solid tumour groups. Cross-resistance analysis with standard drugs revealed the following rank order of correlation coefficients: cytosine arabinoside (AraC) > daunorubicin > doxorubicin > vincristine > prednisolone > 4-hydroperoxycyclophosphamide > etoposide > cisplatin. The high correlation between CdA and AraC was maintained even if the analysis was based only on the haematological tumours. The results indicate that CdA is differentially active against haematological tumours with little or no activity against solid tumours. CdA also appears highly cross resistant with AraC. If this disease-specific information is substantiated in further clinical trials and extended to other phase I-II drugs, non-clonogenic drug resistance assays such as the FMCA may become useful in new drug evaluation, and in targeting specific diagnoses and patients for phase II trials.
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PMID:In vitro activity of 2-chlorodeoxyadenosine (CdA) in primary cultures of human haematological and solid tumours. 794 67

We treated a 16-month-old girl with myelodysplastic syndrome (MDS; refractory anemia with excess of blasts subtype, RAEB by FAB classification) that developed into acute megakaryoblastic leukemia (ANLL-M7). The blast cells were positive for CD41 shown by flow cytometry and for platelet peroxidase by electron microscopy. Cytogenetically, five kinds of abnormal karyotypes were apparent at the initial visit and karyotypic progression (clonal evolution) was also evident. These karyotypes were considered to be derived from the putative original clone, 48,XX, +6, +21. The observed karyotypes were considered 50,XX, +4,add(4)(q31), +6,add(7)(p22),add(10)(q24),add(12)(q11), +20, +21, + mar[karyotype A];48,XX,add(4)(q31), +6,add(10)(q24),add(12)(q11), +21 [karyotype B];48,XX, +6,t(6;13)(p23;q14), +21 [karyotype C];51,XX, +X, t(6;13)(p23;q14), + der(6)t(6;13)(p23;q14), +21, +21, + mar [karyotype D]; and 49,XX, +X, -3,t(6;13)(p23;q14), +der(6)t(6;13)(p23;q14), -12, +21, +21, + mar [karyotype E]. It seems karyotypes B and C were derived from the putative clone; karyotype B developed into karyotype A; and karyotype C developed into karyotype E through karyotype D. After development of ANLL-M7, the cytogenetic study showed a karyotype with further karyotypic progression. The patient was treated with high-dose cytosine arabinoside (HD AraC) followed by allogeneic bone marrow transplantation. Despite intensive care, she died 3 months after the transplantation.
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PMID:Childhood myelodysplastic syndrome with clonal evolution progressing to acute megakaryoblastic leukemia (ANLL-M7). 822 7

Immunophenotype and age have prognostic value in childhood acute lymphoblastic leukemia (ALL) but how this operates is not understood. In 84 children with ALL at initial diagnosis we studied the correlation between these factors and the in vitro resistance to eight drugs, determined with the 3-(4,5-dimethylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide (MTT) assay. B-lineage ALL samples were classified into four differentiation stages: the CD10- proB ALL; cALL; preB ALL with cytoplasmic mu positive ALL cells; and B-ALL with surface immunoglobulin-positive (Ig+) cells. cALL and preB ALL cases have the best prognosis; proB and T-ALL cases show a worse prognosis and B-ALL the poorest prognosis. Patients aged < 18 months and > 10 years have a poor prognosis compared to patients in the intermediate age group. Our results show that cALL and preB ALL cells were the most drug-sensitive cells compared to the other phenotypes. No differences were found between cALL and preB ALL cases with the exception that preB cells were more sensitive to mustine and mafosfamide (Maf). Compared to cALL and preB ALL cases, T-ALL cases were significantly more resistant to prednisolone (Pred), daunorubicin (DNR), L-asparaginase (L-Asp), cytosine arabinoside (AraC), and Maf; proB ALL cases were more resistant to Pred, DNR, L-Asp, and 6-thioguanine. The three B-ALL cases were resistant to vincristine and DNR. Two out of three B-ALL were resistant to Pred. Compared to cells from patients aged 18 months to 10 years, cells from children < 18 months were more resistant to Pred and DNR; cells from children > 10 years were more resistant to Pred. We conclude that cellular drug-resistance patterns might at least partly explain the prognostic value of immunophenotype and age in childhood ALL.
Leukemia 1993 Mar
PMID:Cellular drug resistance profiles that might explain the prognostic value of immunophenotype and age in childhood acute lymphoblastic leukemia. 844 45

A new flow cytometric method is described to detect DNA strand breaks associated with apoptosis, by labeling the 3'-OH termini in the breaks with biotinylated dUTP in a reaction employing exogenous terminal deoxynucleotidyl transferase. The method has been applied in studies on leukemic HL-60 and MOLT-4 cell lines to reveal whether it is specific to apoptotic cells, and whether it can be used in the clinic to detect DNA breakage in leukemic cells during chemotherapy. There was labeling of mononuclear cells in peripheral blood of all 11 patients studied during chemotherapy for acute lymphoblastic, acute myelogenous, or chronic myelogenous leukemia (ALL, AML, or CML) in blastic crisis, indicating induced DNA damage; the number of labeled cells increased from 1-8% before treatment up to 80% during the course of treatment. The DNA topoisomerase inhibitors mitoxantrone, VP-16 (etoposide), and m-AMSA (amsacrine) were more effective in inducing DNA breaks than was hydroxyurea or cytosine arabinoside (AraC). Cells with DNA breaks were identified in peripheral blood for up to 5 days following administration of Mitoxantrone and VP-16. In the case of DNA aneuploid leukemias, the DNA breaks were predominant in the aneuploid cell subpopulations, whereas presumably non-neoplastic diploid cells were unlabeled. In one case of ALL there were two distinct subpopulations of aneuploid cells: one responded to the treatment (by DNA breakage) and the other was non-responding. Thus, cells undergoing apoptosis can be detected by this method of labeling DNA strand breaks and the technique is applicable for analysis of response of leukemic cells to chemotherapy. With this method it may be possible to identify tumor cell sensitivity or resistance to particular drugs early in the course of treatment.
Leukemia 1993 May
PMID:Induction of DNA strand breaks associated with apoptosis during treatment of leukemias. 848 18


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