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Probing platinum-adenine-n3 adduct formation with DNA minor-groove binding agents.

ABSTRACT: Me-lex(py/py), an adenine-N3-selective alkylating agent, and the reversible minor-groove binder netropsin were used to probe the formation of unusual minor-groove adducts by the cytotoxic hybrid agent PT-ACRAMTU ([PtCl(en)(ACRAMTU)](NO(3))(2); en = ethane-1,2-diamine, ACRAMTU = 1-[2-(acridin-9-ylamino)ethyl]-1,3-dimethylthiourea). PT-ACRAMTU was found by chemical footprinting to inhibit specific Me-lex-mediated DNA cleavage at several adenine sites but not at nonspecific guanine, which is consistent with the platination of adenine-N3. In a cell proliferation assay, a significant decrease in cytotoxicity was observed for PT-ACRAMTU, when cancer cells were pretreated with netropsin, suggesting that minor-groove adducts in cellular DNA contribute to the biological activity of the hybrid agent.

SUBMITTER: Rao L

PROVIDER: S-EPMC2930193 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Probing platinum-adenine-n3 adduct formation with DNA minor-groove binding agents.

Rao Lu L West Tiffany K TK Saluta Gilda G Kucera Gregory L GL Bierbach Ulrich U

Chemical research in toxicology 20100701 7

Me-lex(py/py), an adenine-N3-selective alkylating agent, and the reversible minor-groove binder netropsin were used to probe the formation of unusual minor-groove adducts by the cytotoxic hybrid agent PT-ACRAMTU ([PtCl(en)(ACRAMTU)](NO(3))(2); en = ethane-1,2-diamine, ACRAMTU = 1-[2-(acridin-9-ylamino)ethyl]-1,3-dimethylthiourea). PT-ACRAMTU was found by chemical footprinting to inhibit specific Me-lex-mediated DNA cleavage at several adenine sites but not at nonspecific guanine, which is consis ...[more]

PMID: 20578739

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