Measurement of 7,8-dihydro-8-oxo-2′-deoxyguanosine metabolism in MCF-7 cells at low concentrations using accelerator mass spectrometry

• DOI: 10.1073/pnas.0701733104
• Publication Date: 2007-06-26T01:05:26Z
• Authors: Sang Soo Hah; Janna M. Mundt; Hyung M. Kim; Rhoda A. Sumbad; Kenneth W. Turtel...; Paul T. Henderson
• Keywords: Deoxyguanosine; 8-Hydroxy-2'-deoxyguanosine; Adenosine triphosphate

Growing evidence suggests that oxidative damage to cells generates mutagenic 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-oxodG), which may initiate diseases related aging and carcinogenesis. Kinetic measurement of 8-oxodG metabolism repair in has been hampered by poor assay sensitivity difficulty characterizing the flux oxidized nucleotides through relevant metabolic pathways. We report here development a sensitive quantitative approach kinetics sources MCF-7 human breast cancer accelerator mass spectrometry. observed [(14)C]8-oxodG at medium concentrations up 2 pmol/ml was taken cells, phosphorylated mono-, di-, triphosphate derivatives, incorporated into DNA. Oxidative stress caused exposure 17beta-estradiol resulted reduction rate incorporation DNA an increase ratio monophosphate (8-oxodGMP) (8-oxodGTP) nucleotide pool. 17beta-Estradiol-induced up-regulated pool cleansing enzyme MTH1 possibly other Nudix-related pyrophosphohydrolases. These data support conclusion 8-oxodGTP is formed both endogenous reactive oxygen species. The 8-oxodGTP, followed mechanism cellular presence this nucleoside can lead mutations.