Purification and Properties of Cytidine Deaminase from Normal and Leukemic Granulocytes

Ba, Chabner; Dg, Johns; Cn, Coleman; Jc, Drake; Wh, Evans

doi:10.1172/jci107633

Cited by 111 publications

(34 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Cytidine-deaminating activity present in these extracts had an elution volume similar to that of the nonimmunoreactive aminohydrolase. The two activities were differentiated with tetrahydrouridine, a potent inhibitor of cytidine deaminase (22). The adenosine-deaminating activity was not affected by 0.2 AM tetrahydrouridine, while cytidine deamination was reduced to an undectable level.…”

Section: Resultsmentioning

confidence: 99%

Characterization of the residual adenosine deaminating activity in the spleen of a patient with combined immunodeficiency disease and adenosine deaminase deficiency

Schrader

Pollara

Meuwissen

1978

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

A number of infants with an autosomal recessive form of combined immunodeficiency disease also lack adenosine deaminase (adenosine aminohydrolase; EC 3.5.4.4) activity in their erythrocytes. Other tissues from these infants contain only a few percent of the adenosine-deaminating activity present in corresponding normal tissue. The residual adenosine-deaminating activity in extracts from the spleen of a combined immunodeficient, adenosine deaminase-deficient patient was compared with adenosine deaminase from normal spleen. Affinity and immunoadsorbant column chromatography revealed distinct differences between the adenosine-deaminating activity in the patient's spleen and adenosine deaminase from normal spleen. The point of maximum activity and general configuration of the pH optimum curves were also different. erythro -9-(2-Hydroxyl-3-nonyl)adenine, a potent inhibitor of adenosine deaminase from normal spleen, had relatively little effect on the activity from the patient's spleen. In contrast, adenine was a better inhibitor of the activity in the patient's spleen than it was of the enzyme from normal tissue. An adenosine-deaminating activity with the same characteristics and specific activity as that in the patient's spleen was also isolated from normal spleen. These results suggest that the adenosine-deaminating activity in the spleen of this patient is not due to a mutant form of adenosine deaminase.

show abstract

Section: Resultsmentioning

confidence: 99%

Characterization of the residual adenosine deaminating activity in the spleen of a patient with combined immunodeficiency disease and adenosine deaminase deficiency

Schrader

Pollara

Meuwissen

1978

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…The enzyme activity of CDA was determined by the method of Chabner et al (27) with minor modifications. In brief, the supernatant obtained by the methods described above was resuspended in 50 Amol/L [ Messenger RNA analysis.…”

Section: Methodsmentioning

confidence: 99%

Sensitivity to Gemcitabine and Its Metabolizing Enzymes in Neuroblastoma

Ogawa

Hori

Ohta

et al. 2005

Clinical Cancer Research

View full text Add to dashboard Cite

Purpose: We examined the activity of gemcitabine against neuroblastoma in vitro and in vivo. In addition, we investigated the cellular mechanisms of high sensitivity to the agent in neuroblastoma cells. Experimental Design: We examined 11 neuroblastoma cell lines for sensitivity to gemcitabine and other chemotherapeutic agents used clinically for neuroblastoma. The in vivo sensitivity of neuroblastoma to gemcitabine was determined in xenograft models. Furthermore, the major metabolic enzymes of gemcitabine were assessed and compared in leukemia and carcinoma cells. Apoptosis and mitochondrial membrane potentials were also evaluated. Results: The IC 50 s for gemcitabine in 11 neuroblastoma lines ranged between 3 nmol/L and 4 Amol/L.The high activity of gemcitabine against neuroblastoma was confirmedin animal models. Interestingly, enzymes in neuroblastoma cells involved in the metabolism of deoxycytidine analogue have unique characteristics among solid tumors.The median of deoxycytidine kinase activity in neuroblastoma lines was similar to that in leukemia lines, which have low IC 50 s for cytarabine. Cytidine deaminase (CDA) activity in neuroblastoma was hardly detectable and significantly lower than that in carcinoma. The defect of CDA activity was associated with negative expression of mRNA. Furthermore, gemcitabine-induced apoptosis was observed irrespective of the caspase-8 status of neuroblastoma cells, which indicates that apoptosis depends on the mitochondrial pathway. Conclusions: Neuroblastoma is highly sensitive to gemcitabine. Although the cellular mechanism involved in sensitivity to gemcitabine is multifactorial, low CDA activity may contribute high sensitivity in neuroblastoma cells.These results suggest that clinical application of gemcitabine to the treatment of neuroblastoma is warranted.

show abstract

“…The putative mechanism of the dThd effect is that expansion of the intracellular dTTP pool by high extracellular concentrations of dThd simultaneously reduces the dCTP concentration (12,14,26) by inhibiting de novo formation via ribonucleotide reductase (18), and interferes with feedback inhibition of dCyd kinase by dCTP, thus enhancing the phosphorylation of Ara-C (54)(55)(56). dTTP can also inhibit dCMP deaminase (12,24).…”

Section: Resultsmentioning

confidence: 99%

Synergistic interaction between 1-beta-D-arabinofuranosylcytosine, thymidine, and hydroxyurea against human B cells and leukemic blasts in vitro.

Streifel¹,

Howell²

1981

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Isobologram analysis was used to examine the interaction between 1-fiD-arabinofuranosylcytosine (Ara-C), thymidine (dThd), and hydroxyurea. All three pairs of drugs, as well as the triple combination, were synergistic against a human B cell line in vitro across a broad range of concentrations. Synergy was associated with an increase in the Ara-C nucleotide pool and Ara-C triphosphate concentration. dThd increased, and hydroxyurea decreased, the incorporation ofAra-C into trichloroacetic acid-insoluble macromolecules per unit time. Hydroxyurea was more effective than dThd at equimolar concentrations in increasing the acid-soluble Ara-C pool. Maximal stimulation of Ara-C triphosphate formation by dThd occurred at 1 mM and was associated with reduction of the deoxycytidine triphosphate pool to 31% of control. At the same concentration, hydroxyurea increased Ara-C triphosphate formation to a greater extent but increased deoxycytidine triphosphate to 116% of control. When tested at clinically achievable concentrations on blasts from patients with acute leukemia, hydroxyurea increased the Ara-C nucleotide pool in all six cases studied, whereas dThd decreased the Ara-C nucleotide pool. These results indicate that in SB cells dThd and hydroxyurea work by different mechanisms to augment the Ara-C nucleotide pool and that hydroxyurea may be more effective than dThd as a modulator of Ara-C activity in patients with acute leukemia.1-3-D-Arabinofuranosylcytosine (Ara-C) is one of the most important drugs in the treatment of human acute leukemia (1-4). A significant increase in the selectivity of Ara-C may have farreaching consequences for the management ofthis disease. Ara-C behaves as an analog of deoxycytidine (dCyd) that, when phosphorylated to 1-,3-D-arabinofuranosylcytosine triphosphate (Ara-CTP), is a potent inhibitor of DNA polymerase (5-7) and is also incorporated into DNA (7-9). The activity of Ara-C is determined by the amount of Ara-CTP formed within the cell, and the concentration of the natural substrate deoxycytidine triphosphate (dCTP), with which Ara-CTP must compete for binding to DNA polymerase (5, 6, 10, 11).Phosphorylation of Ara-C is normally constrained by feedback inhibition ofdCTP on dCyd kinase, the enzyme catalyzing the rate-limiting step in the dCyd salvage pathway (12, 13). Thymidine (dThd) has been shown to increase the toxicity of Ara-C in vitro and in vivo against several murine (14-17) and human tumors (16). This is in part due to the ability ofthymidine triphosphate (dTTP) to inhibit ribonucleotide reductase (18), which catalyzes an obligatory step in the die novo synthesis of dCTP (19,20) and depletes the cellular dCTP pool (15,18,19,(21)(22)(23)(24)(25)(26). Hydroxyurea (HU) is also an inhibitor of mammalian ribonucleotide reductase (27), but one that binds at a different site than dTTP (28,29). HU has also been demonstrated to enhance the phosphorylation of Ara-C in murine cells (12,(30)(31)(32) and to markedly improve the therapeutic ratio ofAra-C against the murine L1210 leukemi...

show abstract

Purification and Properties of Cytidine Deaminase from Normal and Leukemic Granulocytes

Cited by 111 publications

References 34 publications

Characterization of the residual adenosine deaminating activity in the spleen of a patient with combined immunodeficiency disease and adenosine deaminase deficiency

Characterization of the residual adenosine deaminating activity in the spleen of a patient with combined immunodeficiency disease and adenosine deaminase deficiency

Sensitivity to Gemcitabine and Its Metabolizing Enzymes in Neuroblastoma

Synergistic interaction between 1-beta-D-arabinofuranosylcytosine, thymidine, and hydroxyurea against human B cells and leukemic blasts in vitro.

Contact Info

Product

Resources

About