Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clear metabolic differences between T- and B-cells were demonstrated. Both adenosine deaminase (ADA) and nucleoside phosphorylase (NP) activities increased during logarithmic growth and then decreased in T-cells, but remained essentially constant during the growth cycle of B-cells. When these enzyme activities were examined in a number of T-cell, B-cell, and null cell lines, ADA activity was clearly higher in T-cells as compared to all others. With NP, the opposite appeared to be true, although the differences were much smaller and not statistically significant in all instances. No clear differences were found in the isoenzyme distributions of both enzymes in the various cell types.
J Natl Cancer Inst 1978 Jun
PMID:Differences in purine metabolizing enzyme activities in human leukemia T-cell, B-cell and null cell lines. 41 84

The antibiotic 2'-deoxycoformycin, a potent inhibitor of adenosine deaminase, has potential as a chemotherapeutic agent. Injection of 2'-deoxycoformycin i.v. (0.2 mg/kg) to mice bearing ascites L1210 leukemia cells completely inhibits adenosine deaminase in both erythrocytes and L1210 cells. The recovery of the enzymic activity is markedly different in the two tissues. The recovery is very slow in erythrocytes (13% in 48 hr), whereas 80% recovery occurs during the same time interval in L1210 cells. This marked difference in the recovery of the enzyme in different tissues may play a role in the pharmacological and chemotherapeutic behavior of this drug.
Cancer Res 1979 Apr
PMID:Recovery of 2'-deoxycoformycin-inhibited adenosine deaminase of mouse erythrocytes and leukemia L1210 in vivo. 42 Dec 26

The intracellular adenosine deaminase activities (ADA) in 12 different experimental animal tumours were measured. Unlike the leukaemic lymphoblasts of man, those of two spontaneous rat leukaemias did not have elevated levels of the enzyme. Very high levels were found in a rat plasma-cell tumour (IR 461) and an attempt was made to treat such tumours with the specific enzyme inhibitor, 2-deoxy-coformycin. The shortage of this drug prevented a systematic study, but a daily dose of 8 mg/kg had a significant inhibitory effect on the growth of tumours.
Br J Cancer 1979 Nov
PMID:Levels of adenosine deaminase in some experimental animal tumours and the possible therapeutic effect of the ADA inhibitor 2-deoxy-coformycin. 50 78

N6-Benzyladenosine is a competitive inhibitor of adenosine deaminase from L-1210 cells in axenic culture as well as a potent antiproliferative agent in vitro and in vivo. Potentiation of the growth inhibitory activity of 9-beta-D-arabinosyladenine (ara-A) was observed in the L-1210 system with maximum synergism with a mixture of 16 micron ara-A and 10 micron benzyladenosine. Kinetic studies with L-1210 cell lysates showed values for Km of 0.25 mM ara-A and Ki of 0.23 mM benzyladenosine. It is suggested that ara-A and benzyladenosine in suitable combination may be expected to demonstrate enhanced clinical chemotherapeutic effectiveness.
Cancer Biochem Biophys 1977
PMID:Synergism between the antiproliferative activities of arabinosyladenine and N6-benzyladenosine. 56 24

The metabolic and growth inhibitory effects of adenosine toward the human lymphoblast line WI-L2 were potentiated by the adenosine deaminase inhibitors erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA) and coformycin. EHNA, 5 micron, or coformycin, 3.5 micron, at concentrations that inhibited adenosine deaminase activity more than 90% had little effect on cell growth or the metabolic parameters studied. Adenosine, 50 micron, plus EHNA, 5 micron, arrested cell growth in both parent and adenosine kinase-deficient lymphoblasts, implicating the nucleoside as the mediator of the cytostatic effect. Adenosine, 50 micron, in combination with the adenosine deaminase inhibitors reduced 14CO2 generation from [1-14C]glucose by 38%, depleted 5-phosphoribosyl-1-pyrophosphate by more than 90%, and reduced pyrimidine ribonucleotide concentrations. Uridine, 10 or 100 micron, reversed adenosine plus EHNA growth inhibition in WI-L2 but not in adenosine kinase mutants. Adenine, 500 micron, which may be converted to the same intracellular nucleotides as adenosine, reduced the growth rate by 50% in both parent and adenine phosphoribosyltransferase-deficient lymphoblasts. Although adenine also depleted cells of 5-phosphoribosyl-1-pyrophosphate and reduced pyrimidine ribonucleotide by 50%, the mechanisms of adenine and adenosine toxicity differ. In contrast to the ability of uridine to reverse adenosine cytostasis, growth inhibition by adenine was not reversed by uridine, indicating that pyrimidine ribonucleotide depletion is not the primary mechanisms of adenine toxicity.
Cancer Res 1978 Aug
PMID:Cytotoxic and metabolic effects of adenosine and adenine on human lymphoblasts. 66 33

The enzyme adenosine deaminase has an essential role in lymphocyte metabolism. To examine the in vivo effects of inhibition of this enzyme healthy BDF1 mice were injected intraperitoneally with 2'-deoxycoformycin, a stoichiometric tight-binding inhibitor of adenosine deaminase. Of the treated animals, 20% died of overwhelming infection, and histopathological examination of these, and surviving animals sacrificed 10 days following treatment indicated a selective toxicity to lymphoid cells. No toxicity to tissues other than the lymphoid system was observed, which is consistent with the hypothesis that 2'-deoxycoformycin offers a new and selective approach to the treatment of lymphoid malignancies.
Cancer Chemother Pharmacol 1978
PMID:In vivo toxicity to lymphoid tissue by 2'-deoxycoformycin. 75 Jan 4

Drug combinations of 9-beta-D-arabinofuranosyladenine and 2'-deoxycoformycin were active in the therapy of mice with intracerebral implants of the L1210 tumor. In in vivo mouse brain adenosine deaminase studies, inhibition of 9-beta-D-arabinofuranosyladenine deamination for periods of up to 24 hr was found after a single i.p. dose of 0.002 mmole/kg.
Cancer Res 1977 Jul
PMID:Therapeutic effects of 9-beta-D-arabinofuranosyladenine and 2'-deoxycoformycin combinations on intracerebral leukemia. 86 31

The triple combination of 2'-deoxycoformycin (2'-dCF), 9-beta-D-arabinofuranosyladenine 5'-phosphate, and 9-beta-D-arabinofuranosylcytosine was found to be very effective in the therapy of C57BL X DBA/2 F1 mice with intracerebral L1210. At the dosages and dosage scheduling used, the double combination of 2'-dCF and 9-beta-D-arabinofuranosyladenine 5'-phosphate gave minimal but significant increases in life-span. When 9-beta-D-arabinofuranosylcytosine was given at suboptimal dosage to mice with intracerebral L1210, the host toxicity caused by 2'-dCF and 9-beta-D-arabinofuranosyladenine 5'-phosphate in combination was decreased by a factor of 2, allowing a more prolonged therapy. "Cures" were obtained with the triple combination at dosages of 9-beta-D-arabinofuranosylcytosine that did not "cure". The supernatant adenosine deaminase from C57BL X DBA/2 F1 mouse brains was purified and the Ki for 2'-dCF using 9-beta-D-arabinofuranosyladenine as substrate was determined to be not more than 2 X 10(-11) M.
Cancer Res 1977 Sep
PMID:Effects of 2'-deoxycoformycin, 9-beta-D-arabinofuranosyladenine 5'-phosphate, and 1-beta-D-arabinofuranosylcytosine triple combination therapy on intracerebral leukemia 1210. 88 74

Erythrocyte and lymphocyte adenosine deaminase (ADA) levels were studied in 31 patients with renal cell carcinoma (RCC). Decreased lymphocyte ADA levels occurred in patients with RCC. Erythrocyte ADA levels were reduced only in blood type B and O patients. Nephrectomy resulted in a rise in lymphocyte and erythrocyte ADA levels. Progression of clinical disease was associated with a fall in lymphocyte ADA values in all patients and with a rise in erythrocyte levels only in blood type A patients. Our results suggest that changes in erythrocyte and lymphocyte ADA levels in RCC patients are acquired and may offer insight into host-tumor interactions.
Cancer 1977 Aug
PMID:Adenosine deaminase activity in patients with renal adenocarcinoma. 89 Jun 59

2'-Deoxycoformycin (2'-dCF), a potent inhibitor of adenosine deaminase, was tested in combination with 9-beta-D-arabinofuranosyladenine (ara-A) and 9-beta-D-arabinofuranosyladenine 5'-formate for cytotoxic activity against mouse leukemia L1210 in culture. 2'-dCF, which alone had no activity, significantly enhanced cytostatic and cytotoxic activities of ara-A and its more soluble derivative, 9-beta-D-arabinofuranosyladenine 5'-formate; the latter 2 agents, when tested at equimolar concentrations, were equivalent in their effects on proliferation and viability. The therapeutic response of mice bearing the in vitro line of L1210 cells (L1210/C2) to combination therapy with 2'-dCF and 9-beta-D-arabinofuranosyladenine 5'-phosphate was comparable to that reported elsewhere for therapy of mice bearing the parent in vivo line. Continuous exposure of cultured L1210 cells to ara-A and 2'-dCF induced a prolonged period of unbalanced growth, characterized by inhibition of proliferation and DNA synthesis while RNA and protein synthesis continued; exposure periods in excess of a single population doubling were required to achieve significant cell kill. Potentiation of ara-A activity against the relatively insensitive mouse leukemia L1210 was attributed to increased stability of ara-A resulting from 2'-dCF inhibition of adenosine deaminase.
Cancer Res 1976 Apr
PMID:Enhancement of 9-beta-d-arabinofuranosyladenine cytotoxicity to mouse leukemia L1210 in vitro by 2'-deoxycoformycin. 94 95


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