Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.1 (asparaginase)
 2,695 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cancer and Leukemia Group B undertook a randomized trial of intensification treatment in adults aged 15 to 79 years with acute lymphocytic leukemia (ALL) in complete remission (CR). Daunorubicin (DNR), prednisone, vincristine (VCR), intrathecal (IT) methotrexate (MTX), and asparaginase produced 177 CRs in 277 patients. One hundred fifty-one patients were randomly assigned to receive treatment as follows: 74 received intensive cytarabine and DNR, and 77 received cycles of mercaptopurine (6-MP) and MTX, followed by 6MP, MTX, VCR, and prednisone for 3 years in all. One hundred twelve patients received CNS prophylaxis. Intensification produced major myelosuppression but did not improve remission duration (median, 21 months). Of the 151 patients with CRs who entered the intensification phase, 29% remain in continuous CR (43 to 117 months); in 19 patients, CRs have lasted for longer than 7 years. No relapses occurred after 60 months. Median survival from the time of randomization was 30 months. Those under 30 years of age responded more frequently, with longer CR and survival. While 53% of those aged 15 to 19 years remain in continuous CR, 92% of patients over 59 years have relapsed. The presence of a myeloid antigen on the leukemic cells was adversely prognostic for CR achievement and for survival. Pretreatment WBC and platelet levels independently affected CR duration and survival. Early M1 marrow development presaged longer remissions. CNS relapse occurred in 47 of 256 patients with normal CSF before treatment, in 29 before CNS prophylaxis. CNS disease occurred after CNS prophylaxis in 18 patients: 13 of 61 who had received standard premaintenance and five of 51 who received intensification. No advantage in CR duration or survival resulted from intensive treatment with DNR and cytarabine following induction of CR.
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PMID:The effects of postinduction intensification treatment with cytarabine and daunorubicin in adult acute lymphocytic leukemia: a prospective randomized clinical trial by Cancer and Leukemia Group B. 194 Oct 59

Plasma homocysteine was determined in 12 children with acute lymphoblastic leukemia. The patients were investigated prior to chemotherapy (stage I), during seven weeks of induction chemotherapy (stage II), and thereafter during intermittent high-dose methotrexate (HD-MTX) therapy (stage III). The patients were followed for a period of three to 15 months, and the study included a total of 80 HD-MTX courses. Before start of chemotherapy (stage I), the average plasma homocysteine level in the children with leukemia was 13.18 +/- 6.23 (SD) mumol/liter, which is significantly (P less than 0.001) higher than the level in control children (6.52 +/- 1.21 mumol/liter). The plasma homocysteine level in the patients was positively correlated with the peripheral white blood cell count (P less than 0.01) and negatively correlated with serum folate (P less than 0.02). The serum folate was normal or subnormal in these patients. During induction therapy with cytotoxic drugs such as vincristine, asparaginase, and intrathecal MTX (stage II), there was a drastic change in plasma homocysteine as a function of time. A reciprocal alteration in serum folate was observed, suggesting fluctuating intracellular folate status at this stage of therapy. At the end of stage II (about seven weeks), there was a significant (P less than 0.01) reduction in total homocysteine (to 7.08 +/- 3.84 mumol/liter). HD-MTX (8 g/m2) therapy with 5-formyltetrahydrofolate "rescue" (stage III) was usually begun about seven weeks after start of chemotherapy, and the patients were followed for two to eight courses separated by three to eight weeks. Plasma homocysteine showed a transient increase (26-64%) following each MTX infusion. After three MTX infusions, basal total plasma homocysteine was reduced to 5.56 +/- 1.12 mumol/liter. During most MTX infusions, there was a variable reduction (17-56%) in plasma methionine followed by a rebound increase. It is concluded that plasma homocysteine in children with acute lymphoblastic leukemia is elevated prior to therapy, probably because of occasional folate deficiency and increased burden of proliferating cells. During induction therapy, monitoring plasma homocysteine and serum folate both suggest a labile folate homeostasis, usually a deficiency state. HD-MTX induced a temporary intracellular folate depletion before 5-formyl-tetrahydrofolate was administered, as judged by a transient homocysteinemia. The methionine depletion may interfere with the antileukemic effect of MTX.
Cancer Res 1991 Feb 01
PMID:Plasma homocysteine in children with acute lymphoblastic leukemia: changes during a chemotherapeutic regimen including methotrexate. 198 22

Boys with acute lymphoblastic leukemia (ALL) who have overt testicular relapse (OTR) during initial continuation chemotherapy or within 6 months thereafter have poor outcomes, with long-term survival similar to patients with marrow relapse during treatment. In April 1983, the Pediatric Oncology Group (POG) adopted for these patients an intensive treatment protocol (POG 8303) consisting of a four-drug systemic reinduction (prednisone, vincristine, daunorubicin, and asparaginase), a brief intensive consolidation phase with teniposide and cytarabine, and a 2-year program of continuation chemotherapy with weekly rotating drug pairs (vincristine/cyclophosphamide and teniposide/cytarabine) with or without (by randomization) four-drug reinforcement pulses every 16 weeks. Bilateral testicular radiation (2600 cGy) was administered during reinduction, and intrathecal chemoprophylaxis was given every 4 to 6 weeks. Among 38 eligible study patients with OTR, 5 had prior or concominant extramedullary relapse in other sites. The median duration of complete remission before OTR was 27 months (range, 10 to 42 months). All 38 patients achieved clinical remission after reinduction. Three patients withdrew while in remission, 22 had another relapse (12 marrow, 5 central nervous system (CNS), 2 testicular, 1 retroperitoneal, 1 prostate, and 1 eye), and 13 (34%) remain in complete remission from 32+ to 74+ months after OTR (median, 53+ months). Eighteen patients had their therapy electively discontinued, and five relapses occurred thereafter. These results are superior to those observed in patients with first marrow relapse treated with the same protocol. Approximately one third of patients with OTR treated with POG protocol 8303 exhibit prolonged second remissions with the potential for cure.
Cancer 1991 Jul 01
PMID:Improved treatment results in boys with overt testicular relapse during or shortly after initial therapy for acute lymphoblastic leukemia. A Pediatric Oncology group study. 204 52

Dose and dose intensity are believed critical for attaining a maximal therapeutic effect in drug-responsive tumor systems. Childhood acute lymphoblastic leukemia may be an example of such a drug-responsive system as it is cured with current chemotherapy in a majority of cases. Between August 1981 and May 1983, the Childrens Cancer Study Group enrolled 209 children with ALL and unfavorable presenting features in CCG-193P, a trial based on the Berlin Frankfurt Munster 76/79 regimen. The cumulative delivered dose of each medication was recorded prospectively. Patients who completed the intensive portion of therapy in continuous complete remission were ranked by the percentage of protocol required drug delivered from the initiation of therapy to that date. No association was found between delivery of any single drug and subsequent disease-free survival. However, when patients were ranked by the sum of the percentages of protocol vincristine, l-asparaginase, and anthracycline delivered, children in the approximate middle and lower tertiles were 3 and 5 times more likely to have had a subsequent relapse than were those in the upper tertile (P = 0.025, test for trend). Delivery of the full protocol prescribed dose of these agents may have been critical, but corroboration is certainly needed. Only prospective trials can determine if children with acute lymphoblastic leukemia and unfavorable presenting features might benefit from greater use of vincristine, l-asparaginase, and/or anthracycline.
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PMID:Association of delivered drug dose and outcome for children with acute lymphoblastic leukemia and unfavorable presenting features. 205 67

42 dogs with non-Hodgkin's lymphoma (NHL) were randomized for treatment with either PEG-L-asparaginase 10 IU/kg intramuscularly (n = 22) or L-asparaginase 400 IU/kg intraperitoneally (n = 20). Another 20 dogs were treated with either PEG-L-asparaginase 30 IU/kg (n = 10) or L-asparaginase 400 IU/kg (n = 10). Each treatment protocol consisted of two asparaginase treatments followed by a 10-week period of induction chemotherapy and then maintenance on asparaginase until progression occurred. No significant differences were found between treatments in the response rates after 2 weeks of asparaginase therapy or in the time to relapse, the time to treatment failure or the remission period. The reaction to asparaginase after the initial 2 weeks was a prognostic factor for the total duration of remission under asparaginase maintenance therapy. No side-effects were noted in the dogs treated with PEG-L-asparaginase, whereas 14 (48%) of the L-asparaginase treated dogs had side-effects related to this drug, including anaphylactic shock (9), anorexia or vomiting (4), hypersensitivity-related oedema (3), seizures (1) and acute pancreatitis (1). No abnormalities in clotting times, fibrinogen levels or antithrombin-III levels were found in any of the 62 dogs. PEG-L-asparaginase has the same anti-tumour activity as native L-asparaginase in dogs with NHL, but lacks side-effects.
Eur J Cancer 1990
PMID:Polyethylene glycol-L-asparaginase versus native L-asparaginase in canine non-Hodgkin's lymphoma. 214 33

Between 1973 and 1985, 553 children with childhood acute lymphoblastic leukemia were treated on Dana-Farber Cancer Institute/Children's Hospital, Boston, protocols. The programs featured intensive remission induction therapy, CNS treatment with cranial irradiation and intrathecal drugs, doxorubicin intensification with or without asparaginase, and 2-21/2 years of conventional continuation therapy. There has been progressive improvement in event-free survival for each successive program. Leukemia control concerns pertain to: 1. late relapses (at greater than 5 years) in "standard-risk" patients; 2. an increased incidence of CNS relapses, especially in "standard-risk" patients, as preventative treatment is reduced in intensity; and 3. bone marrow relapses in "high-risk"patients. Comparisons of patients receiving the more intensive arm of each protocol with those receiving the less intensive arm support the hypothesis that more intensive chemotherapy results in improved event-free survival.
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PMID:More is better! Update of Dana-Farber Cancer Institute/Children's Hospital childhood acute lymphoblastic leukemia trials. 218 37

The drugs used to treat cancer today are a confusing array of compounds with differing origins, mechanisms of action, antitumour spectra, and toxicities. There are 5 chemically distinct types of alkylating agents; the prototypical agent is chlormethine (mustine) and the most recent addition is ifosfamide. Generally these drugs all work in the same fashion and their activity is cell cycle proliferation-dependent but phase-nonspecific. The antimetabolites consist of methotrexate, the pyrimidine and purine analogues, and pentostatin, an adenosine deaminase inhibitor and relative newcomer to the class. The individual mechanisms of action of these agents differ but cytotoxicity is generally cell cycle phase-specific. Naturally occurring antineoplastic agents include the vinca alkaloids, the antitumour antibiotics, 1-asparaginase, the epipodophyllotoxins, and homoharringtonine; it is the most diverse collection of compounds. For these drugs as well as the antimetabolites, the therapeutic and toxic effects often depend heavily on duration of exposure to the drug, an effect known as schedule dependency. Finally, the agents that do not fit one of the above categories are cisplatin (cis-platinum II) and its analogue carboplatin (which is being actively investigated), hydroxycarbamide (hydroxyurea), procarbazine, hexamethylmelamine, amsacrine, and mitoxantrone (mitozantrone). In the future we can expect not only the emergence of new antineoplastic drugs, but also further refinements in the use of existing drugs. We are beginning to understand the various types of resistance manifested by tumour cells. Our ability to use these potent and highly toxic agents safely should continue to improve.
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PMID:Antineoplastic drugs in 1990. A review (Part I). 219 Jul 92

The Children's Cancer Study Group instituted a pilot study to investigate the use of high doses of cytosine arabinoside (AraC) in the intensification phase of treatment for acute nonlymphocytic leukemia (ANLL). Patients achieving remission and not eligible for allogeneic bone marrow transplantation were treated with four doses of high-dose AraC and L-asparaginase. These drugs were repeated either on or after 28 days (q28 days), after recovery of hematologic parameters (for the first 49 patients entered onto this trial); or after 7 days (q7 days), despite dropping blood counts (for the last 53 patients enrolled). After completing an additional 3 months of intensification therapy, patients were then allocated by physician choice to either discontinue therapy or receive 18 28-day cycles of maintenance therapy, including the daily administration of 6-thioguanine. Despite three deaths associated with the toxicity of the aggressive (q7 days) AraC timing, patients receiving this approach demonstrated equal or better disease-free survival from the end of induction (55% versus 42% actuarially at 3 years [P = 0.52]). Maintenance therapy appeared to play no role in improving outcome for people who received the aggressive timing of AraC cycles. Fifty-nine percent were alive disease free actuarially at 3 years from the decision to not give maintenance therapy (n = 27) compared with 62% for those receiving maintenance therapy (n = 16; P = 0.49). On the other hand, patients who received the less aggressive AraC intensification timing (q28 days) had an improved survival rate if maintenance therapy was administered (n = 17) (65% versus 39% for patients not receiving maintenance therapy [n = 24] at 3 years [P = 0.07]). Maintenance therapy therefore may not improve outcome in patients receiving aggressive timing of high-dose AraC but may be important in less intensive postremission regimens in childhood ANLL.
Cancer 1990 Sep 15
PMID:The role of timing of high-dose cytosine arabinoside intensification and of maintenance therapy in the treatment of children with acute nonlymphocytic leukemia. 220 52

A 10-year-old boy with leukaemia-associated hypercalcaemia was treated with aminohydroxypropylidene biphosphonate (AHPrBP previously APD) in a total dosage of 60 mg over 5 days, when the condition failed to respond to rehydration and frusemide and no sustained effect was produced by haemodialysis with a calcium (Ca)-free dialysate. Bone films showed no lytic lesions, and AHPrBP, which is a potent inhibitor of osteoclast-mediated bone resorption was well tolerated and induced a rapid and sustained fall in plasma Ca (from 3.42 to 2.07 mM in 5 days). Plasma magnesium and alkaline phosphatase remained normal. The results could have been affected by other drugs [vincristine, cyclophosphamide, zorubicin (Rubidazone) L-asparaginase and prednisone] which were simultaneously administered. However, the observation that: (1) the response curve of plasma Ca was similar to that reported when AHPrBP was used alone, (2) there was complete inhibition of urinary Ca excretion and (3) hypocalcaemia occurred suggests that AHPrBP was the major cause of the reduction in plasma Ca. AHPrBP should be considered a potential therapy for hypercalcaemia in childhood malignancy.
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PMID:Leukaemia-associated hypercalcaemia in a 10-year-old boy: effectiveness of aminohydroxypropylidene biphosphonate. 224 18

Twenty-seven evaluable children with early first bone marrow relapse of acute lymphoblastic leukemia were treated with an intensive induction/consolidation and ongoing maintenance therapy. Induction therapy consisted of a 35-day course of daunomycin, vincristine, and prednisone, immediately followed by teniposide, cytosine arabinoside (Ara-C), and L-asparaginase. Intrathecal methotrexate, hydrocortisone, and Ara-C were given through the induction/consolidation phase. Twenty-three of 27 patients achieved remission by the end of induction/consolidation. Maintenance with the same drugs in a modified dosage schedule continued for approximately 2 years. A small subgroup of patients who were M3 at day 35 but M1 at day 56 (end of induction/consolidation) and had a cumulative event-free survival (EFS) of only 0.40 at 6 months, all had relapsed by 15 months. However, the EFS for M1 patients by day 35 and maintained on chemotherapy was 0.64 at 12 months and 0.32 at 30, 36, and 48 months, respectively. Although good reinduction and remission duration rates at 12 to 24 months were achieved and an apparent plateau in survival occurs at 30 months, fall-off in survival would not be unexpected with probably less than 20% alive after 5 years.
Cancer 1990 Dec 15
PMID:Multiagent chemotherapy in relapsed acute lymphoblastic leukemia in children. 224 89


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