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)

A recently developed flow cytometric assay method using patient tumor cells allows the determination not only of their sensitivity to cytostatic drugs but also of biochemical and biophysical parameters after treatment, such as esterase concentration and intracellular pH of the living cells. DNA-content of the dead cells and cell volume of living and dead cells. The T-cell lines CEM, Molt4, Jurkat, the B-cell lines RPMI1788, Daudi, Raji and the promyelocytic line HL60 were incubated with: cytosine arabinoside (ara-C), L-asparaginase, daunorubicin, vincristine and prednisone for 48 h. Living cells then stained with esterase and pH-dye 1,4-diacetoxy-2,3-dicyanobenzene (ADB) and dead cells with DNA-dye propidium-iodide (PI). The esterase concentration, an index of metabolic activity, decreased in the T-cell lines under the influence of ara-C, daunorubicin and vincristine, whereas in the B-cell lines smaller changes in esterase concentration were observed (P less than 0.001). A decrease in intracellular pH was seen in the ara-C and daunorubicin-incubated cells Molt4, CEM and HL60, whereas in the B-cell lines no significant change in intracellular pH was found. In all lines except Jurkat the cell volume of the surviving cells increased under the influence of certain drugs (primarily ara-C and daunorubicin); B-cell lines showed a greater swelling than T-cell lines (P = 0.001).
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PMID:Flow-cytometric determination of intracellular pH, esterase activity and cell volume in human leukemic cell lines following in vitro incubation with cytostatic drugs. 248 10

Human bone marrow cells from 20 patients as well as the permanent human B-cell lines RPMI 1788, Raji, Daudi, T-cell lines Molt, CEM, Jurkat and the promyelocytic line HL 60 were assayed by means of a newly developed in vitro flow cytometric cytostatic drug assay. The cells were exposed to cytosine-arabinoside, L-asparaginase, daunorubicin, prednisone or vincristine. Surviving cells were stained after an incubation period of 2 to 7 days with esterase and pH-indicator dye ADB (1,4-diacetoxy-2,3-dicyanobenzene), dead cells with DNA-dye PI (propidium iodide). Dose-response curves were established using percent surviving cells. It was possible to evaluate bone marrow samples from 16 out of 20 patients. Seven samples were leukemic (acute myeloid leukemia (AML) n = 6, Non-Hodgkin's Lymphoma (NHL) n = 1). Nine samples were from patients either in complete remission or with benign diseases. Daunorubicin and cytosine-arabinoside were cytotoxic in both groups, whereas vincristine was effective mainly in the leukemic group (p less than 0.05). There was significant heterogeneity in the reactivity of AML-marrow cells from different patients to different drugs. The cell lines exhibited different patterns of sensitivity. Vincristine arrested cells in G2/M-phase, cytosine-arabinoside caused an increase of cells in the S-phase.
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PMID:Cytostatic drug testing in human leukemias by means of multiparametric flow cytometry. 367 21

L-asparaginase (EC 3.5.1.1) was purified to homogeneity from Thermus thermophilus. The apparent molecular mass of L-asparaginase was found to be 33 kDa by SDS-PAGE, whereas by Sephacryl S-300 superfine column it was found to be 200 kDa, indicating that the enzyme in the native stage acts as hexamer. It is a thermostable enzyme and keeps all of its activity at 80 degrees C for 10 min. The antiproliferative activity of the purified L-asparaginase from T. thermiphilus was tested against the following human cell lines: K-562 (chronic myelogenous leukemia), Raji (Burkitt's lymphoma), SK-N-MC (primitive neuroectodermal tumor), HeLa (cervical cancer), BT20 and MCF7 (breast cancers), HT-29 (human colon cancer), and OAW-42 (ovarian cancer). The antiproliferative activity of T. thermophilus enzyme was compared with Erwinase, the commercially available L-asparaginase from Erwinia corotovora. The potency difference between the two L-asparaginases was greater in HeLa and SK-N-MC than in other cell lines. The fact that L-asparaginase from T. thermophilus does not hydrolyse L-glutamine makes it advantageous for future clinical trials.
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PMID:Antitumor activity of L-asparaginase from Thermus thermophilus. 1126 87