Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

L-Asparaginase sensitivity and asparagin-deficiency of 5 tumor cell populations, i.e. mouse lymphoma L-1210, LI0-1, LTL, Berkitt lymphoma and human ovary cancer, line CaOv were studied. Radiometric estimation of 3H-thimidine incorporation into the cells of DNA served a criterion of cytotoxicity. "Krasnitin" (FDR) was used as L-asparaginase. The cells of leukemia L-1210, lymphosarcoma LIO-1 and line CaOv were asparagine-independent and non-sensitive to L-asparaginase. The cells of mouse lympholeukemia LTL and the cultures of Berkitt human lymphoma proved to be asparagin-dependent and highly sensitive to L-asparaginase. In concentration of 50 IU/ml the drug inhibited incorporation of 3H-thimidine in the cells of LTL and Berkitt lymphoma by 97-98 and 75-80 per cent respectively. Inhibition of 3H-thimidine incorporation in the cells of LTL and Berkitt lymphoma was more pronounced after incubation with the drug for 8 and 24 hours respectively. Two out of the 5 tumor cell populations were chosen as a result of the study. One of these 2 populations, i.e. the cells of Berkitt lymphoma was asparagin-dependent and highly sensitive to L-asparaginase, the other, i.e. the cells of line CaOv was asparagin-independent and resistant to the specific antitumor effect of the enzyme. The use of a system of these two cell lines provided estimation of the ratio of the specific cytostatic (antitumor activity) and non-specific cytostatic properties in the preparations with L-asparaginase activity.
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PMID:[Cellular test system for studying the biological properties of preparations with L-asparaginase activity]. 59 48

Depletion of glutamine with Acinetobacter glutaminase:asparaginase promotes melphalan uptake by and cytotoxicity to murine L1210 cells in vitro. Combined treatment of tumor bearing mice with these two agents increases the therapeutic response.
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PMID:Enhancement of melphalan therapy with glutaminase:asparaginase. 72 23

A number of chemotherapeutic agents, including L-asparaginase, actinomycin D, chloroethylcyclohexy-nitrosourea, 5-flourouracil, cyclophosphamide, hydroxyurea, cis-platinum, adriamycin and methotrexate, alone and in combination and at variable dose levels, were applied against the Dunning R3327 rat prostatic adenocarcinoma-subline G. We found a continuing parallel between responses of the human and rat tumors and conclude that the usefulness of this animal model as a screening system for agents against the human tumor is further supported.
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PMID:Further experience with chemotherapy in the Dunning prostatic adenocarcinoma. 75 23

22 patients received intravenously infused L-asparaginase (Escherichia coli) on a protocol for 5 weekly doses. 13 patients received 100 U/kg, 1 patient 500 U/kg, and 8 patients 1,500 U/kg. Only 3 of the 9 patients receiving 500 U/kg or more were able to complete the 5-week protocol. 11 of the 13 patients receiving 100 U/kg were able to complete the 5-week protocol. Significant tumor responses were not seen. CNS toxicity and allergic reactions were observed at high- and low-dose levels. There was no difference as to the degree of protein changes, BUN elevation, or liver function abnormalities at the different dose levels.
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PMID:Phase I study of L-asparaginase (NSC 109229). 76 51

Asparaginase [EC 3.5.1.1.] of Escherichia coli, an anti-tumor enzyme, was inactivated in a time-dependent fashion by mushroom tyrosinase [EC1.14.18.1.]. The inactivation did not proceed, however, when heat-inactivated tyrosinase was used. Exculusion of the atmospheric oxygen or addition of diethyldithiocarbamate, a copper selective chelating agent, prevented the inactivation. The difference absorption spectrum of tyrosinase-inactivated asparaginase versus intact asparaginase exhibited the appearance of marked absorption peaks at 300 and 350 nm. These results indicate that the tyrosyl residue(s) of asparaginase, which is essential for the activity is enzymatically modified by tyrosianes.
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PMID:Studies of enzyme-catalyzed modification of proteins. I. Tyrosinase-catalyzed modification of asparaginase. 81 77

An undifferentiated human pancreatic carcinoma has been established in continuous culture and is grown in Dulbecco's modified. Eagle's medium fortified with 10% fetal calf serum and 2.5% horse serum. The established cell line (MIA PaCa-2) has a doubling time of 40 h. The cells are large with abundant cytoplasm, exhibit a high degree of aneuploidy and have a tendency to grow on top of other cells. MIA PaCa-2 grows in soft agar with a colony-forming efficiency of 19%. Both MIA PaCa-2 cells and a cell line from another pancreatic carcinoma obtained from National Cancer Institute (NCI) are sensitive to asparaginase, a property not shared by several other human tumor cell lines tested.
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PMID:Human pancreatic carcinoma (MIA PaCa-2) in continuous culture: sensitivity to asparaginase. 83 18

A number of therapeutic agents including L-asparaginase, Actinomycin-D, CCNU, Hydroxyurea, 5-FU, Cis-platinum, Cyclophosphamide, orchiectomy, Adriamycin and DES alone and in various combinations has been applied against the Dunning R-3327 rat prostatic adenocarcinoma subline G. We have found a parallel between the results of this study and those of similar therapeutic application to the human tumor. We conclude that this animal model may prove to be a useful screening system for agents against human prostatic cancer.
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PMID:Chemotherapy of the transplantable adenocarcinoma (R-3327) of the Copenhagen rat. 91 40

L-Asparaginase (L-asparagine amidohydrolase, EC 3.5.1.1) B from Acinetobacter calcoaceticus has been purified by precipitation with streptomycin, chromatography on DEAE-cellulose and CM-cellulose, gel filtration on Agarose and chromatography on phosphocellulose. The molecular weight of the enzyme was found to be 130 000. The enzyme was rather insensitive to pH changes between 7 and 9. The Michaelis constant was 3-10(-3) M. Hg2+, Cu2+, and Ni2+ as well as high ionic strength inhibited the activity of the enzyme, whereas citrate seemed to stimulate the activity. The enzyme catalyzed the deamination of L-glutamine to about the same extent as L-asparagine. The temperature stability of the enzyme is also reported. The enzyme had a weak tumor inhibitory power.
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PMID:Purification and properties of L-asparaginase B from Acinetobacter calcoaceticus. 93 83

At least two chemotherapeutic agents, prednisone and L-asparaginase, have been demonstrated to produce pancreatic injury. Early diagnosis of pancreatitis is frequently not possible, as symptoms are vague, physical findings may be minimal, and laboratory studies are frequently inconclusive until the injury is severe. Abdominal echography, as a monitor of pancreatic size, has proven to be helpful in the diagnosis of subclinical and early pancreatic injury of 14 of 19 selected children receiving prednisone and/or L-asparaginase therapy for acute leukemia or non-Hodgkin's lymphoma at the M.D. Anderson Hospital and Tumor Institute. Employment of this new diagnostic method permits prompt withdrawal of the causative agent(s), thus preventing further insult.
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PMID:Early detection of chemotherapy-related pancreatic enlargement in children using abdominal sonography: a preliminary report. 99 Oct 74

A method potentially capable of enhancing the effectiveness of therapeutic enzymes such as L-asparaginase was investigated. The method was suggested by the following properties that have been observed for lectins injected into tissues: (1) six lectins with differing specificities were retained near the site of injection in the feet of mice 10 to 100 times longer than several non-lectin proteins. Prolonged retention of 125I-labelled concanavalin A was also observed in other normal and malignant mouse tissues. (2) The retention of 125I-labelled concanavalin A was not affected by prior immunization against concanavalin A. (3) Electrophoresis of tissue extracts on sodium dodecyl sulfate-poly-acrylamide gels followed by radioautography indicated that the 125I-labelled concanavalin A retained in the tissue remained as intact in form as prior to injection. Since the therapeutic efficacy of many enzymes may be enhanced by localization at the intended site of action, in principle it should be possible to enhance the effectiveness of therapeutic enzymes by combining the tissue-localizing properties of a lectin with therapeutic effectiveness of the enzyme. A conjugate of E. coli L-asparaginase and concanavalin A has been prepared by covalent cross-linking with glutaraldehyde and has been shown to be retained in mouse tissue 90 times longer than the free enzyme. However, it is completely ineffective in the treatment of the L-asparaginase-sensitive lymphosarcoma 6C3HED in C3H/HeJ mice. The ineffectiveness of the conjugated enzyme may be associated with the interiorization of the conjugate by the cells of the tumor.
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PMID:Effect of localization of L-asparaginase as the concanavalin A conjugate on anti-tumor activity. 103 89


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