The expression of bacterial nitroreductase in transgenic mice results in specific cell killing by the prodrug CB1954.
The enzyme nitroreductase, isolated from Escherichia coli B, converts CB1954 ((5-aziridin-1-yl)-2,4-dinitro-benzamide) into a cytotoxic DNA interstrand cross-linking agent. The E. coli B gene (nfnB, NTR) encoding nitroreductase (NTR) was cloned into eukaryotic expression vectors. When driven by a CMV promoter, 5-10% of the stably transfected mouse fibroblasts expressed the NTR enzyme. These cells were killed at a concentration of 20 microM CB1954 in comparison to nonexpressing cells which were killed at a much higher concentration (500 microM). We subsequently generated transgenic mice to test the prodrug system in vivo. Nitroreductase was expressed specifically in T cells driven by the control elements of the human CD2 locus. Upon CB1954 treatment, transgenic mice show extensive cell depletion in thymus and spleen (14-16% of normal cell numbers), whereas all other tissues are unaffected by prodrug administration. These results raise the possibility of using the NTR gene in anticancer therapy.
Drabek
D
D
Department of Cell Biology and Genetics, Institute of Cell Biology, Rotterdam, The Netherlands.
Guy
J
J
Craig
R
R
Grosveld
F
F
D000818:Animals; D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001388:Aziridines / Q000378:metabolism / Q000494:pharmacology*; D018929:Cell Culture Techniques; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015870:Gene Expression; D015316:Genetic Therapy / Q000379:methods*; D051379:Mice; D008822:Mice, Transgenic; D009601:Nitroreductases / Q000235:genetics* / Q000378:metabolism; D011355:Prodrugs / Q000378:metabolism / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000201:enzymology; D014162:Transfection
D000970:Antineoplastic Agents; D001388:Aziridines; D011355:Prodrugs; C100099:tretazicar; D009601:Nitroreductases