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)

Aplastic anemia is the most severe hematologic side-effect. All chemotherapeutic agents, with the exception of bleomycin and L-asparaginase, may induce aplasia, but the degree of hematotoxicity varies according to the drug. With the exception of acute leukemia in which drug-induced aplasia is part of the treatment, aplasia must be prevented through perfect knowledge of the posology and injection schedules for each drug, as well as by adjusting doses to the patient's hematological status. If aplasia develops, intensive hematological care is requisite. The most common cardiac side-effect is toxic cardiomyopathy caused by anthracyclines, which must be diagnosed early by EKG recordings before each injection and repeated ultrasonography or dynamic cardiac scintigraphy. The risk of toxic cardiomyopathy makes it requisite not to exceed the maximal doses set for each drug. Pulmonary side-effects include acute hypersensitivity pneumopathy and chronic diffuse interstitial fibrosis, the latter being more common and mainly caused by bleomycin. The risk of chronic fibrosis demands that patients be closely monitored and that the total dose be kept under 300 mg. Renal toxicity usually results in acute transient renal failure, as with cisplatinum, and requires a thorough biological study before each injection. Vesical hemorrhage, which is threatening in some instances, may occur with cyclophosphamide. VM26 and VP16 may induce anaphylactic shock. Allergic symptoms are possible with L-asparaginase and bleomycin.
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PMID:[Adverse effects of antitumor and antileukemic chemotherapy. 2]. 629 58

Between June 1977 and December 1979, 72 evaluable patients with childhood non-T-cell acute lymphoblastic leukemia were induced into complete remission using vincristine, prednisone, and doxorubicin. All received asparaginase consolidation and central nervous system prophylaxis with cranial irradiation and intrathecal methotrexate. All patients then received prolonged intensification with vincristine, prednisone, and doxorubicin, and half of them were randomized to receive weekly high-dose asparaginase. Continuation therapy was with vincristine, prednisone, methotrexate, and 6-mercaptopurine. After a median follow-up of 57 months, there were four remission deaths and 25 relapses. Central nervous system relapse was the first event in 4% of patients. There were fewer treatment failures in the asparaginase-treated group [2-sided, p = 0.04 (0.07 controlling for standard and high-risk groups)]. Asparaginase toxicity occurred in six patients (8%) and was self-limited, but it precluded further use of the drug in those patients. The major toxicity of this treatment program was drug-induced cardiomyopathy which occurred in 10 patients (14%) and was fatal in three of them. In summary, we conclude that the intensive use of high-dose asparaginase has an important role in the treatment of children with acute lymphoblastic leukemia. The morbidity of multiple doses of doxorubicin outweighed its antileukemic advantage in standard-risk patients.
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PMID:Influence of intensive asparaginase in the treatment of childhood non-T-cell acute lymphoblastic leukemia. 635 20

Cytostatic antibiotics of the anthracycline class are the best known of the chemotherapeutic agents that cause cardiotoxicity. Alkylating agents such as cyclophosphamide, ifosfamide, cisplatin, carmustine, busulfan, chlormethine and mitomycin have also been associated with cardiotoxicity. Other agents that may induce a cardiac event include paclitaxel, etoposide, teniposide, the vinca alkaloids, fluorouracil, cytarabine, amsacrine, cladribine, asparaginase, tretinoin and pentostatin. Cardiotoxicity is rare with some agents, but may occur in >20% of patients treated with doxorubicin, daunorubicin or fluorouracil. Cardiac events may include mild blood pressure changes, thrombosis, electrocardiographic changes, arrhythmias, myocarditis, pericarditis, myocardial infarction, cardiomyopathy, cardiac failure (left ventricular failure) and congestive heart failure. These may occur during or shortly after treatment, within days or weeks after treatment, or may not be apparent until months, and sometimes years, after completion of chemotherapy. A number of risk factors may predispose a patient to cardiotoxicity. These are: cumulative dose (anthracyclines, mitomycin); total dose administered during a day or a course (cyclophosphamide, ifosfamide, carmustine, fluorouracil, cytarabine); rate of administration (anthracyclines, fluorouracil); schedule of administration (anthracyclines); mediastinal radiation; age; female gender; concurrent administration of cardiotoxic agents; prior anthracycline chemotherapy; history of or pre-existing cardiovascular disorders; and electrolyte imbalances such as hypokalaemia and hypomagnesaemia. The potential for cardiotoxicity should be recognised before therapy is initiated. Patients should be screened for risk factors, and an attempt to modify them should be made. Monitoring for cardiac events and their treatment will usually depend on the signs and symptoms anticipated and exhibited. Patients may be asymptomatic, with the only manifestation being electrocardiographic changes. Continuous cardiac monitoring, baseline and regular electrocardiographic and echocardiographic studies, radionuclide angiography and measurement of serum electrolytes and cardiac enzymes may be considered in patients with risk factors or those with a history of cardiotoxicity. Treatment of most cardiac events induced by chemotherapy is symptomatic. Agents that can be used prophylactically are few, although dexrazoxane, a cardioprotective agent specific for anthracycline chemotherapy, has been approved by the US Food and Drug Administration. Cardiotoxicity can be prevented by screening and modifying risk factors, aggressively monitoring for signs and symptoms as chemotherapy is administered, and continuing follow-up after completion of a course or the entire treatment. Prompt measures such as discontinuation or modification of chemotherapy or use of appropriate drug therapy should be initiated on the basis of changes in monitoring parameters before the patient exhibits signs and symptoms of cardiotoxicity.
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PMID:Cardiotoxicity of chemotherapeutic agents: incidence, treatment and prevention. 1078 23

Although patients with cancer may derive much benefit from treatment, they are at risk for developing life-threatening complications. Hypersensitivity reactions can be severe, as in the case of anaphylaxis with L-asparaginase. Cardiac toxicities consist of arrhythmias with various drugs, hemorrhagic myocarditis with cyclophosphamide and ifosfamide, cardiomyopathy with anthracyclines, and pericardial disease. Acute respiratory failure may occur as a result of ARDS caused by ATRA or cytarabine, from interstitial fibrosis, or from pulmonary veno-occlusive disease. Hemorrhagic cystitis caused by cyclophosphamide and ifosfamide can be severe and result in exsanguination if unresponsive to treatment. Disseminated intravascular coagulation and thrombotic microangiopathy can produce thrombotic or hemorrhagic complications. Gastrointestinal toxicities include significant hepatotoxicity with a variety of drugs and development of acute surgical abdomen.
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PMID:Acute life-threatening toxicity of cancer treatment. 1152 52

Many children and adolescents with cancer receive chemotherapeutic agents that are cardiotoxic. Thus, while survival rates in this population have improved for some cancers, many survivors may experience acute or chronic cardiovascular complications that can impair their quality of life years after treatment. In addition, cardiac complications of treatment lead to reductions in dose and duration of chemotherapy regimens, potentially compromising clinical efficacy. Anthracyclines are well known for their cardiotoxicity, and alkylating agents, such as cyclophosphamide, ifosfamide, cisplatin, busulfan, and mitomycin, have also been associated with cardiotoxicity. Other agents with cardiac effects include vinca alkaloids, fluorouracil, cytarabine, amsacrine, and asparaginase and the newer agents, paclitaxel, trastuzumab, etoposide, and teniposide. The heart is relatively vulnerable to oxidative injuries from oxygen radicals generated by chemotherapy. The cardiac effects of these drugs include asymptomatic electrocardiographic abnormalities, blood pressure changes, arrhythmias, myocarditis, pericarditis, cardiac tamponade, acute myocardial infarction, cardiac failure, shock, and long-term cardiomyopathy. These effects may occur during or immediately after treatment or may not be apparent until months or years after treatment. Mild myocardiocyte injury from chemotherapy may be of more concern in children than in adults because of the need for subsequent cardiac growth to match somatic growth and because survival is longer in children. Primary prevention is therefore important. Patients should be educated about the cardiotoxic risks of treatment and the need for long-term cardiac monitoring before chemotherapy is begun. Cardiotoxicity may be prevented by screening for risk factors, monitoring for signs and symptoms during chemotherapy, and continuing follow-up that may include electrocardiographic and echocardiographic studies, angiography, and measurements of biochemical markers of myocardial injury. Secondary prevention should aim to minimize progression of left ventricular dysfunction to overt heart failure. Approaches include altering the dose, schedule, or approach to drug delivery; using analogs or new formulations with fewer or milder cardiotoxic effects; using cardioprotectants and agents that reduce oxidative stress during chemotherapy; correcting for metabolic derangements caused by chemotherapy that can potentiate the cardiotoxic effects of the drug; and cardiac monitoring during and after cancer therapy. Avoiding additional cardiotoxic regimens is also important in managing these patients. Treating the adverse cardiac effects of chemotherapy will usually be dependent on symptoms or will depend on the anticipated cardiovascular effects of each regimen. Treatments include diuresis, afterload reduction, beta-adrenoceptor antagonists, and improving myocardial contractility.
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PMID:Cardiotoxicity of cancer chemotherapy: implications for children. 1597 64