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

Nine children with mediastinal non-Hodgkin's lymphoma (NHL) were treated according to our new regimen which is characterized by intensified therapy with high-dose cytosine arabinoside (HDCA). After induction therapy with a combination of five drugs, such as vincristine, doxorubicin, cyclophosphamide, 1-asparaginase, and prednisolone, intermediate dosages of methotrexate (MTX) (1 g/m2) and HDCA (1.5 g/m2 x 12 doses) were administered. All but one patient (88.9%) achieved complete remission and then received this intensified therapy. With a median follow-up period of 25.5 months, five patients are still in complete remission, but three patients have relapsed. From the phenotypic point of view, these relapsed patients showed only very immature T-cell differentiation antigens such as CD2 and CD7 (or CD5). These results suggest that HDCA as intensified therapy for children with mediastinal NHL seems to be effective. However, for patients with an immature phenotype of T-lineage cells, more sophisticated regimens should be prepared.
Cancer 1989 Feb 15
PMID:Poor prognosis of mediastinal non-Hodgkin's lymphoma with an immature phenotype of CD2+, CD7 (or CD5)+, CD3-, CD4-, and CD8-. 278 59

There is ample evidence of the value of intensive therapeutic strategies in the management of acute lymphoblastic leukemia (ALL), the commonest form of malignant disease in children. Such a program, devised at the Dana-Farber Cancer Institute (DFCI), Boston, and incorporating high-dose L-asparaginase, was adopted in 1984 by the Children's Hospital at Chedoke-McMaster, Hamilton, Ont., and the Children's Hospital of Western Ontario, London. We describe the experience of these institutions in the treatment of 82 children with ALL, 19 of whom were switched to the DFCI protocols while in continuing first remission with other treatment programs to complete a minimum of 2 years of maintenance therapy; the remaining 63 children, who had recently diagnosed disease, were consecutively enrolled in the DFCI protocols. Each child was assigned at diagnosis to a category of risk for relapse and treated accordingly. There were no remission induction failures or deaths due to induction therapy among the patients with newly diagnosed disease. There were no differences in total or event-free survival rates between the patients in Hamilton and those in London or between those whose protocols were switched and those who were treated from the beginning with the DFCI protocols. With a median follow-up interval of 144 weeks the total survival rate was 95% and the event-free survival rate 88%. For patients at standard risk of relapse the event-free survival rate was 100%, for those at high risk the rate was 82%, and for those at very high risk the rate was 67%. If infants (all of whom suffered a relapse) are excluded from the last category the rate was 89%. These results were achieved with moderate toxic effects (except for two deaths, one of which was due to a therapeutic misadventure) and suggest that the prospect for cure in children with ALL. may now approximate 80%, a degree of success that demands that consideration be given to reducing total therapy, at least for children with standard-risk disease. Further follow-up will determine whether these high event-free survival rates will stabilize and meet the criteria for cure.
 ...
PMID:Management of Ontario children with acute lymphoblastic leukemia by the Dana-Farber Cancer Institute protocols. 279 Jun 5

To evaluate gonadal function and pregnancy outcome after treatment for acute lymphoblastic leukemia during childhood or adolescence, 44 former patients who were less than 20 years of age at diagnosis, 5 or more years from diagnosis, and 18 or more years of age were contacted. Thirty-nine (88%) provided information regarding pregnancy outcome. Gonadal function as estimated by the ability to conceive or sire a pregnancy, was not impaired despite treatment with substantial cumulative doses of methotrexate, 6-mercaptopurine, vincristine, and 1-asparaginase. Twelve patients reported a total of 27 pregnancies. There were four spontaneous abortions, one stillborn, and 22 liveborn infants. The birthweights were 1928 to 4536 g (median, 3430 g). Two infants had congenital anomalies. The childrens' ages ranged from 1 month to 10 years, 2 months (median, 6 years, 1 month). None has been diagnosed with any type of childhood cancer. The results of this study suggest that pregnancy outcome is not affected adversely by treatment received during childhood or adolescence for acute lymphoblastic leukemia.
Cancer 1989 Dec 01
PMID:Pregnancy outcome after treatment for acute lymphoblastic leukemia during childhood or adolescence. 280 24

A human renal carcinoma cell line (Caki-1) was examined for asparagine (Asn) dependence and susceptibility to Escherichia coli asparaginase. Because this enzyme hydrolyzes glutamine (Gln) as well as Asn, even though at only 2-3% the rate, Asn- Gln+ and Asn- Gln- media were prepared. Only the former supported Caki growth. The Asn- Gln- medium was then repleted with Asn, Gln, or both. Although Asn repletion failed to promote growth, addition of Gln alone or the combination supported growth as well as complete medium. With [3H]leucine and [3H]mannose incorporation to indicate protein and glycoprotein synthesis, respectively, the Gln repleted medium supported these processes as well as complete medium. Asparaginase added to complete medium was highly toxic to the Caki cells, but this is a reflection of Gln depletion rather than Asn depletion.
Cancer Lett 1988 Dec 15
PMID:Human renal carcinoma: asparagine independence with asparaginase susceptibility in culture. 290 36

Four hundred thirty patients with high-risk acute lymphoid leukemia were entered on the acute leukemia in childhood protocol (AlinC 12) of the Pediatric Division of the Southwest Oncology Group (now the Pediatric Oncology Group) between 1976 and 1979. This study was a prospective randomized comparison of two regimens that had as their primary differences: (1) an intensification period with Cytoxan (cyclophosphamide) and asparaginase after induction; (2) a period of intravenous methotrexate before initiating maintenance; and (3) in the regimen that had those two additions, triple-drug chemoprophylaxis of the central nervous system (CNS) using methotrexate, hydrocortisone, and cytosine arabinoside as compared to cranial irradiation and intrathecal methotrexate. All patients received vincristine and prednisone induction, 6-mercaptopurine and methotrexate maintenance, and vincristine and prednisone pulse intensification. There was no significant difference in the rate of bone marrow relapse. However, overall disease-free survival favored the arm with intensification and chemoprophylaxis because of a lesser incidence of extramedullary relapse. Thus, for treatment 1 versus treatment 3 the two-sided P values were for overall disease-free survival 0.16; bone marrow relapses 0.13; all CNS relapses 0.04; and all extramedullary disease relapses 0.013. It is concluded that intensification as delivered in this protocol protects against testicular relapse and that chemoprophylaxis is adequate prophylaxis against isolated CNS relapse.
Cancer 1989 Jan 01
PMID:A comparison of two regimens for high-risk acute lymphocytic leukemia in childhood. A Pediatric Oncology Group Study. 291 Apr 21

Four hundred thirty-four children, with good-risk acute lymphocytic leukemia (ALL), were assigned randomly to receive intensive or less intensive maintenance therapy with 6-mercaptopurine and methotrexate, plus vincristine and prednisone pulses in such a way that patients on treatment 1 had their leukocyte counts maintained between 1500 and 3000/mm3. Patients on treatment 2 had leukocyte counts maintained between 3000 and 4500/mm3. Absolute granulocyte counts were maintained above 500/mm3 on both groups. All children received induction treatment with vincristine, prednisone and L-asparaginase and had central nervous system (CNS) prophylaxis with cranial irradiation and intrathecal methotrexate. The overall remission rate was 94%. Event-free survival at 8 years was 44% (SE, 5.6%). There was no significant difference in outcome between treatments 1 and 2 (P = 0.83). The incidence of infection was similar overall and not significantly different between treatment arms.
Cancer 1989 Apr 15
PMID:Treatment intensity and outcome for children with acute lymphocytic leukemia of standard risk. A Pediatric Oncology Group Study. 292 55

We reviewed the English-language literature pertaining to drug-induced pancreatitis and attempted to determine whether the reported association between each drug and pancreatitis was valid. The following drugs seem to cause pancreatitis: azathioprine, chlorothiazide and hydrochlorothiazide, oestrogens, frusemide, 6-mercaptopurine, methyldopa, sulphonamides, sulindac, tetracycline and valproic acid. Less convincing but suggestive evidence exists for colaspase, chlorthalidone, combination cancer chemotherapy, cimetidine, cisplatin, corticosteroids, cytosine arabinoside, diphenoxylate, ethacrynic acid, iatrogenic hypercalcaemia, methandienone, metronidazole, nitrofurantoin, pentamidine, phenformin, piroxicam and procainamide. In general, pancreatitis is a very rare complication of treatment with these drugs. The pathogenesis of the pancreatitis is usually obscure, but is probably mediated by an immune response. Certain drugs such as oestrogens cause hypertriglyceridaemia, which in turn may lead to pancreatitis.
 ...
PMID:Drug-induced pancreatitis. 304 64

For the purpose of clinical application to the therapy of human leukemia and lymphosarcoma, L-asparaginase from Escherichia coli was modified with 2,4-bis(O-methoxypolyethylene glycol)-6-chloro-s-triazine (activated PEG2) by an improved method, which involves a purification step of activated PEG2 by gel filtration. The PEG2-modified asparaginase retained approximately 30% (73 IU/mg of protein) of the enzymic activity of the native enzyme, while it had almost wholly lost the immunoreactivity towards anti-asparaginase antibodies. The modified enzyme retained the characteristics of the native enzyme in terms of the pH- and temperature-dependencies of activity and stability, and the Km value for L-asparagine. Administration of the modified enzyme to a dog with spontaneous lymphosarcoma induced complete remission without any toxic side effects. Seven children with multiple relapses of acute leukemia were treated with a regimen of cycles of methotrexate and native asparaginase. Three of these children developed anaphylactic shock. In contrast to the native enzyme, the successive administration of PEG2-modified asparaginase to those three patients was therapeutically effective without causing any allergic reaction.
Jpn J Cancer Res 1986 Dec
PMID:Characterization of polyethylene glycol-modified L-asparaginase from Escherichia coli and its application to therapy of leukemia. 310 31

Human DNA ligase was purified from different kinds of immunocompetent cells: thymocytes, normal and stimulated lymphocytes, blasts from ALL (Burkitt and non-T, non-B) and ANLL (M1, M2, and M5). Based upon the protocol for the treatment of these leukemias, the purified enzymes were assayed in the presence of routinely used combinations of antileukemic drugs. At the range of concentration tested (between 0.1 and 5 microM) some drugs taken separately were totally inactive on the enzyme from the different sources. For those being inhibitory, when used in combination their effect was always different from what was observed when the compound was tested alone. Some combinations were more effective in inhibiting the enzyme from leukemic than from normal cells (vincristine + cyclophosphamide + prednisone in ALL and rubidazone + Ara-C, Ara-C + m-AMSA, in ANLL). However, some combinations of drugs are without effect on ligase from leukemic cells at this dose range (vincristine + rubidazone + Ara-C + prednisone and adriamycin + asparaginase + Ara-C in ALL or etoposide + Ara-C, adriamycin + cyclophosphamide in ANLL). This is the first direct observation of the effect of cytostatic drugs on DNA ligase, a key enzyme of the DNA replication and repair process. The clinical consequences of these observations are discussed in an attempt to selectively inhibit replication, thereby division, of cancer cells.
 ...
PMID:Effects of clinical combinations of antileukemic drugs on DNA ligase from human thymocytes and normal, stimulated, or leukemic lymphocytes. 325 60

After examining the in vitro cell-kill kinetics of various anticancer drugs by using cultured human cell lines, Shimoyama et al. classified the drugs into two groups according to the types of action: 1) type-I drugs (cytocidal and concentration-dependent action) such as alkylating agents and anticancer antibiotics; 2) type-II drugs (cytostatic and time-dependent action) such as antimetabolites, Vinca alkaloids and L-asparaginase. In the present paper, we will present a rational basis for such a classification by using cell-kill pharmacodynamic models, and consider the optimal dosage regimen depending on the type of drugs by combining the cell-kill kinetic and pharmacokinetic models. In these models, classification of the drugs depends on whether the cell population is kinetically homogenous or not. It is assumed that cell population is homogenous for type-I drugs and there exist both drug sensitive and insensitive cell populations for type-II drugs. The concentration (or dose)-time-cell survival curves in both in vitro and in vivo, which are simulated based on the kinetic models, are consistent with the experimental data found in the literature. Further analysis on the optimal dose regimen according to these kinetic models clarified that the type-I drugs showed a similar cell-kill effect irrespective of the mode of administration as long as the area under the plasma unbound concentration curves (AUCp, free) is kept constant, while the type-II drugs are more effective by multiple dosing or infusion regimen than single administration of a large dose of drugs. In other words, the extents of AUCp, free and the residence time in the plasma (above certain concentrations of drugs) are determinants of the in vivo cell-kill effects of type-I drugs and type-II drugs, respectively. If the pharmacokinetics of newly developed anticancer drugs in human are predicted from the animal data according to the so-called "animal scale-up" technique and combined with the in vitro cell-kill kinetic data by the use of proposed kinetic models, one may obtain not only the optimal dosage regimen but also good screening systems for truly active drugs for the treatment of human cancer.
 ...
PMID:[Quantitative analysis of cell-kill effects of anticancer drugs: consideration of both in vitro and in vivo experimental systems]. 331 99


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>