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)

The ability to accumulate and retain the active metabolite of Ara-C varies widely among patients. Our studies demonstrate a significant correlation between clinical response and the pharmacokinetics of Ara-CTP in leukemia cells during therapy. Knowledge of the cellular pharmacology of Ara-CTP has been used to optimize dose rates and to design combination treatment schedules. An understanding of the cellular pharmacodynamics of other drugs is likely to be a useful parameter for planning treatment protocols.
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PMID:Pharmacologically directed design of leukemia therapy. 218 51

We gave 4 days of high-dose Ara-C followed 2 days later by rHUGM-CSF (which continued until the neutrophil count was greater than 1000/microliters) to 12 patients with newly diagnosed AML and a relatively poor prognosis. Six CRs occurred, there were four deaths during induction, and in only one case was there an rHUGM-CSF-associated growth of leukemia. The pattern of hematologic recovery was variable but in some patients rHUGM-CSF seemed to accelerate normal myelopoiesis following chemotherapy. Continued investigation of rHUGM-CSF and chemotherapy in AML is warranted.
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PMID:Treatment of poor-prognosis, newly diagnosed acute myelogenous leukemia with high-dose cytosine arabinoside (Ara-C) and rHUGM-CSF. 218 63

A study of treated murine acute myeloid leukemia (AML) with an emphasis on the bone marrow stromal function is reported. Leukemia was induced in C57Bl mice through intraperitoneal (i.p.) inoculation of C-1498 myelogenous leukemic cells. The leukemic mice were administered: (1) total body lethal X-irradiation (t.b.i.); (2) two i.p. cytosine-arabinoside (Ara-C) injections followed by X-irradiation. Control mice received similar regimens. Bone marrow of experimental and control mice was processed for stromal cell cultures (SCC) and in vitro engraftment of hematopoietic cells onto the cultures. The results of this study indicate that the bone marrow stromal deficiency which occurs in leukemia is aggravated by Ara-C and irradiation treatments. Moreover, SCC of treated leukemic mice sustain in vitro hematopoiesis only to a limited degree. Stromal deficiency, as possible cause for graft failure in bone marrow transplanted leukemic patients, is discussed.
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PMID:Cumulative bone marrow stromal damage caused by X-irradiation and cytosine-arabinoside in leukemic mice. 218 23

Differentiation therapies try to change the malignant cell in order to acquire a more mature or normal phenotype. Various ways were tested in leukemia: suppression the proliferative pressure by low dose Ara-C, enhancement of the differentiation by retinoic acid derivatives or by differentiation factors, and modulation of the cell metabolism interrupting an autocrine loop (a growth factor and its receptor). The treatment is given continuously at small doses, during a long period of time. In all these cases it seems necessary to tailor the differentiation therapy to each category of leukemia.
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PMID:Differentiating agents in the treatment of leukemia and myelodysplastic syndromes. 220 24

Based on in vitro evidence of time-dependent synergistic kill of HL-60 leukemia cells exposed to Ara-C and mitoxantrone, 44 patients with relapsed or refractory AML and 3 with blastic CML were treated with a timed sequence of both drugs. There were 25 females and 22 males, with a median age of 53 (range 21-75). Of 31 patients with relapsed AML, 24 had one prior remission, 6 had two and 1 had three. Of these, 15 had failed a second reinduction attempt. Thirteen patients were primarily refractory to induction with Ara-C plus daunorubicin. Each dose of Ara-C, 500 mg/m2, was followed after 6 hr by mitoxantrone, 5 mg/m2, and the sequence was repeated four to six times (44-68 hr) in different cohorts of patients. All but two patients (one with blastic CML and one in relapse and refractory) are evaluable for response and toxicity. Of 16 patients in relapse without prior reinduction 7 achieved CR and 3 PR (62% response rate); there were 3 CR in the 14 patients who were in relapse and refractory (21% response rate) and 4 CR and 1 PR (35% response rate) in the 14 patients with primary anthracycline resistance. Five of seven patients previously exposed to mitoxantrone achieved CR. Response lasted from 2 to 42 months, with two patients alive and in continuing remission at 34 and 42 months. Average marrow recovery was seen after 25 days and time to remission was 30 days. Six patients died in induction (four from sepsis and two from the tumor lysis syndrome) and 21 had progressive disease. Chemotherapy was well tolerated with minor nausea and vomiting in 13 patients, moderate in 20, and severe in 2. Most patients did not have evidence of drug-induced mucositis: it was minor in 9 and moderate in 2. Renal dysfunction was attributable to the use of nephrotoxic antibiotics. Hepatic dysfunction was reversible and was minor in 10 patients, moderate in 13, and severe in 3. Sequential, timed administration of intermediate-dose Ara-C and mitoxantrone is an active and well-tolerated antileukemic regimen.
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PMID:Sequential intermediate-dose cytosine arabinoside and mitoxantrone for patients with relapsed and refractory acute myelocytic leukemia. 220 4

In this study we investigated glucose tolerance in relation to autologous bone marrow transplantation (ABMT). In 13 adult patients with acute myeloblastic (AML) or lymphoblastic (ALL) leukaemia in complete remission (CR), intravenous glucose tolerance test (IVGTT) was performed 1 month before and 6 months after ABMT. Patients with AML in CR received, as myeloablative therapy, cyclophosphamide combined with busulphan or total body irradiation (TBI). ALL patients received total body irradiation in combination with vincristine, daunorubicin, Ara-C, cyclophosphamide and prednisone. Before ABMT all patients, in spite of the intensive chemotherapy given for remission induction and consolidation, had a normal glucose tolerance. However, 6 months after the transplantation the k-value (rate of glucose elimination) for this group of patients had decreased (p less than 0.01). The trend towards impaired glucose tolerance was correlated with lower peak insulin values during IVGTT (p less than 0.05). Thus, the myeloablative therapy in connection with ABMT caused an impairment of pancreatic beta-cell function. No patient has hitherto developed clinical diabetes mellitus.
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PMID:Impaired glucose tolerance after autologous bone marrow transplantation. 220 56

We previously administered ara-C at a dose rate of 250 mg/m2/hr for 36-72 hr to patients with leukemia. Gastrointestinal toxicity was dose-limiting. This regimen was modified to an every other day schedule, administering 24-hr periods of high dose continuous infusion ara-C, each followed by a 24-hr rest period. Sixteen patients with relapsed/refractory acute myeloid leukemia (AML) (N = 4), secondary AML (N = 2), relapsed/refractory acute lymphoblastic leukemia (N = 7), or CML in blast crisis (N = 3) received this regimen of three 24-hr infusions with two intercurrent 24-hr rest periods. Grade 3 gastrointestinal toxicity was encountered in 57% of the courses, and hypoplasia was achieved in all patients. Three of the patients died while hypoplastic, two with septicemia and another with intracranial hemorrhage. There were five responding patients (2 CRs, 3 PRs). Median steady-state plasma ara-C levels were 24 microM, 22 microM, and 20 microM during the first, second, and third 24-hr infusions, respectively. Ara-C levels ranged from 4-118 microM during the infusions and were always below 4.5 microM during the rest periods. A significant level of ara-C incorporation into DNA was detected in each of the five patients studied, thus demonstrating that (ara-C)DNA formation is detectable in blasts from patients receiving high dose continuous infusion ara-C therapy. These findings suggest that alternate day continuous infusion ara-C may be useful in the treatment of acute leukemia and CML in blast crisis.
Leukemia 1990 Dec
PMID:A phase I study of intermittent continuous infusion high dose cytosine arabinoside for acute leukemia. 224 7

The assays for the detection of unlabeled 1-beta-D-arabinofuranosylcytosine (cytosine arabinoside, Ara-C) incorporation into DNA was simplified. The procedure includes DNA isolation from leukemic cells, quantification of DNA concentrations, breakdown by enzymatic digestion of DNA to nucleosides and a radioimmunoassay (RIA) using an antibody against Ara-C. Different techniques for quantification of DNA concentrations are compared. A fluorimetric technique using Hoechst 33258 is preferred because it is the most specific method. Comparison of this RIA assay with measurement of [3H]-Ara-C/DNA formation under similar conditions in HL-60 cells showed a correlation of 0.99. Ara-C incorporation into DNA of leukemic cells was studied using two rat-leukemia cell lines, one of which is sensitive to Ara-C and the other is an Ara-C-resistant wild type: BNML-Cl/0 and BNML-Cl/Ara-C, respectively. The results showed that Ara-C is incorporated when the cells are incubated at concentrations equal to or higher than the Ara-C concentration that induces 50% growth inhibition after 48 h incubation (IC50). This implies that at lower Ara-C concentration, i.e. levels that do not induce cytotoxicity, Ara-C is not incorporated into DNA. Similar results were obtained with human HL-60 myeloid leukemia cells. The detection limit of this assay is 2 pmol/ml Ara-C; therefore, the assay is more sensitive than measurement of Ara-C triphosphate (Ara-CTP), the only metabolite that can be measured in leukemic cells from patients after in vivo Ara-C administration. On the basis of in vitro studies, the finding of detectable Ara-C/DNA levels in vivo is expected to correlate with cytotoxicity; whether or not the Ara-C/DNA level itself is informative remains to be evaluated.
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PMID:A simplified assay for measurement of cytosine arabinoside incorporation into DNA in Ara-C-sensitive and -resistant leukemic cells. 224 32

The knowledge about drug resistance in childhood leukemias and acute lymphoblastic leukemia (ALL) in general is limited. This is because of the lack of a suitable in vitro drug sensitivity assay, which is in part due to low in vitro ALL cell survival. We recently adapted the highly efficient 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay to test cells from ALL patients and showed that its results were comparable with those of the DiSC assay, up to now the most valid but laborious assay. In this study, in vitro drug sensitivity was assessed in cells from 82 children with leukemia, 79 of whom had ALL, with the MTT assay. Dose response curves were obtained for 6-mercaptopurine, 6-thioguanine (6-TG), prednisolone (Pred), daunorubicin (DNR), vincristine (VCR), cytosine arabinoside (Ara-C), L-asparaginase (L-Asp), mafosfamide, and mustine. A cytotoxic effect of methotrexate could be detected in only a few cases. Large interindividual differences in drug sensitivity were detected. Compared with leukemia cells from newly diagnosed patients, leukemia cells from relapsed patients were significantly more in vitro resistant to 6-TG, Pred, Ara-C, mafosfamide and mustine but not to DNR, VCR, and L-Asp. Improvements of culture medium and methods to increase MTT reduction were studied. From 10 components tested, addition of insulin and bovine serum albumin to serum-containing medium improved ALL cell survival. Addition of succinate did not increase the amount of MTT reduction. We conclude that the in vitro MTT assay highly facilitates large-scale studies on drug resistance of ALL patients that can lead to rational improvements in existing treatment protocols.
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PMID:In vitro drug sensitivity of cells from children with leukemia using the MTT assay with improved culture conditions. 225 5

A 36-year-old man with acute myelogenous leukemia, refractory to the combination chemotherapy, developed fungal infection and acute respiratory distress. Simultaneously, rapid proliferation of leukemic cells was observed in the blood. He was given continuous drip infusion of etoposide (50 mg/day) and Ara-C (20 mg/day) for 18 days. The leukemic cells disappeared from both the blood and the marrow, and complete remission was achieved. There was no adverse effect related to this therapy. The low dose combination chemotherapy with etoposide and Ara-C is safe to be carried out, and could be effective for the patients with refractory leukemia.
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PMID:[Low dose continuous infusion therapy with etoposide (VP-16) and cytosine arabinoside (Ara-C) for a patient with refractory acute myelogenous leukemia]. 228 79


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