Resistance to cytosine arabinoside by retrovirally mediated gene transfer of human cytidine deaminase into murine fibroblast and hematopoietic cells

• Published in: Cancer gene therapy Vol. 3; no. 5; p. 331
• Main Authors: Momparler, R L, Eliopoulos, N, Bovenzi, V, Létourneau, S, Greenbaum, M, Cournoyer, D
• Format: Journal Article
• Language: English
• Published: England 01-09-1996
• Subjects: Animals; Blotting, Northern; Blotting, Southern; Cell Division - drug effects; Cells, Cultured; Clone Cells - drug effects; Cytarabine - pharmacology; Cytidine Deaminase - genetics; Cytidine Deaminase - metabolism; DNA - antagonists & inhibitors; DNA, Viral - analysis; Drug Resistance - genetics; Gene Expression Regulation - genetics; Gene Transfer Techniques; Genetic Vectors - genetics; Hematopoiesis - drug effects; Mice; Polymerase Chain Reaction; Retroviridae - genetics; Transduction, Genetic - genetics
• ISSN: 0929-1903

Dose-limiting hematopoietic toxicity produced by the cytosine nucleoside analogue cytosine arabinoside (ARA-C) is one of the major factors that limit its use in the treatment of neoplastic diseases. An interesting approach to overcome this problem would be to insert a gene for drug resistance to ARA-C in normal hematopoietic cells to protect them from drug toxicity. The deamination of ARA-C by cytidine deaminase results in a loss of its antineoplastic activity. The objective of this study was to determine if gene transfer of human cytidine deaminase into murine fibroblast and hematopoietic cells would confer drug resistance to ARA-C. Retrovirally mediated transfer of the human cytidine deaminase gene into 3T3 fibroblasts resulted in efficient expression of the proviral RNA for this gene and in increased cytidine deaminase activity in cytoplasmic extracts. These cells showed marked resistance to ARA-C as determined by the effects of this drug on colony formation, cell growth, and DNA synthesis. The transfer of the human cytidine deaminase gene into murine bone marrow cells by the retroviral vector conferred a high level of drug resistance to ARA-C in clonogenic assays. These studies indicate that the cytidine deaminase gene could be used in cancer gene therapy by protecting normal hematopoietic cells against the cytotoxic effects of ARA-C and related cytosine nucleoside analogues.