title: Tyrosyl-DNA phosphodiesterase as a target for anticancer therapy.
abstract: Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is a recently discovered enzyme that catalyzes the hydrolysis of 3'-phosphotyrosyl bonds. Such linkages form in vivo following the DNA processing activity of topoisomerase I (Top1). For this reason, Tdp1 has been implicated in the repair of irreversible Top1-DNA covalent complexes, which can be generated by either exogenous or endogenous factors. Tdp1 has been regarded as a potential therapeutic co-target of Top1 in that it seemingly counteracts the effects of Top1 inhibitors, such as camptothecin and its clinically used derivatives. Thus, by reducing the repair of Top1-DNA lesions, Tdp1 inhibitors have the potential to augment the anticancer activity of Top1 inhibitors provided there is a presence of genetic abnormalities related to DNA checkpoint and repair pathways. Human Tdp1 can also hydrolyze other 3'-end DNA alterations including 3'-phosphoglycolates and 3'-abasic sites indicating it may function as a general 3'-DNA phosphodiesterase and repair enzyme. The importance of Tdp1 in humans is highlighted by the observation that a recessive mutation in the human TDP1 gene is responsible for the inherited disorder, spinocerebellar ataxia with axonal neuropathy (SCAN1). This review provides a summary of the biochemical and cellular processes performed by Tdp1 as well as the rationale behind the development of Tdp1 inhibitors for anticancer therapy.
authors.affiliation: Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Bethesda, MD 20892-4255, USA.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Dexheimer
authors.forename: Smitha
authors.initials: S
authors.lastname: Antony
authors.forename: Christophe
authors.initials: C
authors.lastname: Marchand
authors.forename: Yves
authors.initials: Y
authors.lastname: Pommier
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D004249:DNA Damage; D004260:DNA Repair; D006801:Humans; D008958:Models, Molecular; D015394:Molecular Structure; D009369:Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D010726:Phosphodiesterase Inhibitors / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D011485:Protein Binding; D013379:Substrate Specificity
chemical_list: D000970:Antineoplastic Agents; D010726:Phosphodiesterase Inhibitors; D010727:Phosphoric Diester Hydrolases; C122147:tyrosyl-DNA phosphodiesterase