title: Inhibition of DNA glycosylases via small molecule purine analogs.
abstract: Following the formation of oxidatively-induced DNA damage, several DNA glycosylases are required to initiate repair of the base lesions that are formed. Recently, NEIL1 and other DNA glycosylases, including OGG1 and NTH1 were identified as potential targets in combination chemotherapeutic strategies. The potential therapeutic benefit for the inhibition of DNA glycosylases was validated by demonstrating synthetic lethality with drugs that are commonly used to limit DNA replication through dNTP pool depletion via inhibition of thymidylate synthetase and dihydrofolate reductase. Additionally, NEIL1-associated synthetic lethality has been achieved in combination with Fanconi anemia, group G. As a prelude to the development of strategies to exploit the potential benefits of DNA glycosylase inhibition, it was necessary to develop a reliable high-throughput screening protocol for this class of enzymes. Using NEIL1 as the proof-of-principle glycosylase, a fluorescence-based assay was developed that utilizes incision of site-specifically modified oligodeoxynucleotides to detect enzymatic activity. This assay was miniaturized to a 1536-well format and used to screen small molecule libraries for inhibitors of the combined glycosylase/AP lyase activities. Among the top hits of these screens were several purine analogs, whose postulated presence in the active site of NEIL1 was consistent with the paradigm of NEIL1 recognition and excision of damaged purines. Although a subset of these small molecules could inhibit other DNA glycosylases that excise oxidatively-induced DNA adducts, they could not inhibit a pyrimidine dimer-specific glycosylase.
authors.affiliation: Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, Oregon, United States of America.
authors.forename: Aaron C
authors.initials: AC
authors.lastname: Jacobs
authors.affiliation: Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, Oregon, United States of America.
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Calkins
authors.affiliation: National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America.
authors.forename: Ajit
authors.initials: A
authors.lastname: Jadhav
authors.affiliation: National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America.
authors.forename: Dorjbal
authors.initials: D
authors.lastname: Dorjsuren
authors.affiliation: National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America.
authors.forename: David
authors.initials: D
authors.lastname: Maloney
authors.affiliation: National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America.
authors.forename: Anton
authors.initials: A
authors.lastname: Simeonov
authors.affiliation: Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, United States of America.
authors.forename: Pawel
authors.initials: P
authors.lastname: Jaruga
authors.affiliation: Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, United States of America.
authors.forename: Miral
authors.initials: M
authors.lastname: Dizdaroglu
authors.affiliation: Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, Oregon, United States of America ; Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon, United States of America.
authors.forename: Amanda K
authors.initials: AK
authors.lastname: McCullough
authors.affiliation: Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, Oregon, United States of America ; Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon, United States of America.
authors.forename: R Stephen
authors.initials: RS
authors.lastname: Lloyd
mesh_terms: D000818:Animals; D045647:DNA Glycosylases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D043224:Deoxyribonuclease (Pyrimidine Dimer) / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D057075:Enzyme Assays; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D007700:Kinetics; D051379:Mice; D010084:Oxidation-Reduction; D011485:Protein Binding; D011687:Purines / Q000737:chemistry* / Q000494:pharmacology; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D054852:Small Molecule Libraries / Q000737:chemistry* / Q000494:pharmacology; D013379:Substrate Specificity
chemical_list: D004791:Enzyme Inhibitors; D011687:Purines; D011994:Recombinant Proteins; D054852:Small Molecule Libraries; D043224:Deoxyribonuclease (Pyrimidine Dimer); C468347:NTHL1 protein, human; D045647:DNA Glycosylases; C473634:NEIL1 protein, human; C479058:oxoguanine glycosylase 1, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase