Abstract
Cytidine triphosphate (CTP) synthetase is a key enzyme in the anabolic pathways of
cytosine and uracil ribonucleotide metabolism. The enzyme catalyses the conversion
of uridine triphosphate (UTP) into CTP, and has a high activity in various malignancies,
which has led to the development of inhibitors of CTP synthetase for therapeutic purposes.
We studied both CTP synthetase activity and ribonucleotide concentrations in leukaemic
cells of 12 children suffering from acute non-lymphocytic leukaemia (ANLL), and performed
incubation experiments with cyclopentenyl cytosine (CPEC), a nucleoside analogue that
is capable of inhibiting CTP synthetase.The CTP synthetase activity in ANLL cells
(5.1±2.3 nmol CTP/mg/h) was significantly higher compared with granulocytes of healthy
controls (0.6±0.4 nmol CTP/mg/h, P=0.0002), but was not different from the CTP synthetase activity in non-malignant
CD34+ bone marrow cells (5.6±2.4 nmol CTP/mg/h). Major shifts were observed in the
various ribonucleotide concentrations in ANLL cells compared with granulocytes: the
absolute amount of ribonucleotides was increased with a substantial rise of the CTP
(2.4 versus 0.4 pmol/μg protein, P=0.0007) and UTP (8.7 versus 1.6 pmol/μg protein, P=0.0007) concentrations in ANLL cells compared with granulocytes. Treatment of ANLL
cells in vitro with CPEC induced a major depletion (77% with 2.5 μM of CPEC) in the concentration
of CTP, whilst the concentrations of the other ribonucleotides remained unchanged.
Therefore, the high activity of CTP synthetase in acute non-lymphocytic leukaemic
cells can be inhibited by CPEC, which provides a key to a new approach for the treatment
of ANLL.
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to European Journal of CancerAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Increased CTP synthetase activity in cancer cells.Nature. 1978; 271: 71-72
- Biochemical strategy of cancer cells and the design of chemotherapy.Cancer Res. 1983; 43: 3466-3492
- Increased cytidine 5′-triphosphate synthetase activity in rat and human tumors.Cancer Res. 1980; 40: 3921-3927
- Cytidine triphosphate synthetase activity in lymphoproliferative disorders.Cancer Res. 1983; 43: 1432-1435
- The roles of uridine-cytidine kinase and CTP synthetase in the synthesis of CTP in malignant human T-lymphocytic cells.Leukemia. 1994; 8: 1375-1378
- Increased activity of cytidine triphosphate synthetase in pediatric acute lymphoblastic leukemia.Adv. Exp. Med. Biol. 1998; 431: 667-671
- Imbalance in the nucleotide pools of myeloid leukemia cells and HL-60.Cancer Res. 1987; 47: 1841-1847
- Autologous bone marrow transplantation versus intensive consolidation chemotherapy for acute myeloid leukemia in childhood.N. Engl. J. Med. 1996; 334: 1428-1434
- Phase I clinical trial of continuous infusion cyclopentenyl cytosine.Cancer Chemother. Pharmacol. 1995; 36: 513-523
- Induction of differentiation in the human promyelocytic leukemia cell-line HL-60 by the cyclopentenyl analogue of cytidine.Biochem. Pharmacol. 1986; 35: 1841-1848
- Antitumor activity and biochemical effects of cyclopentenylcytosine in mice.Cancer Res. 1986; 46: 3325-3329
- Cellular pharmacology of cyclopentenyl cytosine in Molt-4 lymphoblasts.Cancer Res. 1991; 51: 3733-3740
- Enhancement of the toxicity and DNA incorporation of arabinosyl-5-azacytosine and 1-β-d arabinofuranosylcytosine by cyclopentenyl cytosine.Cancer Res. 1990; 50: 7279-7284
- Synergistic interaction between 3-deazauridine and arabinosylcytosine in mice bearing L1210 leukemia.Proc Am Assoc Cancer Res. 1980; 21: 277-281
- Modulation of cytosine arabinoside toxicity by 3-deazauridine in a murine leukemia model.Leukemia Res. 1991; 15: 229-236
- Purine and pyrimidine enzymic programs and nucleotide pattern in sarcoma.Cancer Res. 1983; 43: 1019-1023
- Imbalance between the pyrimidine ribonucleotide pools of rat pheochromocytoma PC-12 cells.Clin. Chem. Enzym. Comms. 1993; 5: 315-319
- Purine and pyrimidine nucleotide patterns of normal, differentiating and regenerating liver and of hepatomas in rats.Cancer Res. 1980; 40: 1286-1291
- Imbalance in the ribonucleotide pools of lymphoid cells from acute lymphoblastic leukemia patients.Leukemia Res. 1986; 10: 389-396
- Cytidine triphosphate synthase activity and mRNA expresssion in normal human blood cells.Biol. Chem. 1999; 380: 41-46
- High gradient magnetic cell separation with MACS.Cytometry. 1990; 11: 231-238
- Magnetic activated cell sorting (MACS) — a new immunomagnetic method for megakaryocytic cell isolation.Eur. J. Haematol. 1994; 52: 267-275
- PCR-positivity in harvested bone marrow predicts relapse after transplantation with autologous purged bone marrow in children in second remission of precursor B-cell acute leukaemia.Br. J. Haematol. 1997; 96: 395-402
Ruiz ME. Tissue culture techniques. In Schrader WT, O'Malley BW, eds. Laboratory Methods Manual for Hormone Action and Molecules in Endocrinology, 12th edn. Houston, Houston Biological Association 1988, 14:3–14:38.
- Nucleotide profiles of normal human blood cells determined by high-performance liquid chromatography.Anal. Biochem. 1985; 147: 197-209
- Measurement of protein content using bicinchonic acid.Anal. Biochem. 1985; 150: 76-85
- Determination of CTP synthetase in a crude cell homogenate by a fast and sensitive non-radiochemical assay using anion-exchange high performance liquid chromatography.J. Chromatogr. 1997; 693: 287-295
- A simplification of the protein assay method of Lowry et al. which is more generally applicable.Anal. Biochem. 1977; 83: 346-356
- Enzymology of pyrimidine and carbohydrate metabolism in human colon carcinomas.Cancer Res. 1982; 42: 1176-1183
- Inhibition of CTP synthetase induces differentiation of HL-60 and down-regulation of the c-myc oncogene.Adv. Exp. Med. Biol. 1995; 370: 761-764
- Studies on the antitumor and biochemical actions of cyclopentenyl cytosine against human colon carcinoma HT-29 in vitro and in vivo.Life Sci. 1999; 64: 103-112
- In vitro characterization of the myelotoxicity of cyclopenetenyl cytosine.Cancer Chemother. Pharmacol. 1994; 34: 103-108
- The molecular basis of mutations induced by deoxyribonucleoside triphosphate pool imbalances in mammalian cells.Exp. Cell Res. 1989; 181: 305-316
- Regulation of 1-β-d arabinofuranosylcytosine 5-triphosphate accumulation in human leukemia cells by deoxycytidine 5-triphosphate.Cancer Res. 1986; 46: 1079-1083
- Optimizing therapy for acute myeloid leukemia based on differences in intracellular metabolism of cytosine arabinoside between leukemic blasts and normal blood cells.Ther. Drug Monit. 1996; 18: 341-349
Article info
Publication history
Accepted:
January 20,
2000
Received in revised form:
January 19,
2000
Received:
September 1,
1999
Identification
Copyright
© 2000 Elsevier Science Ltd. Published by Elsevier Inc. All rights reserved.
