Corpus ID: 9820596

8-Hydroxylation of guanine bases in kidney and liver DNA of hamsters treated with estradiol: role of free radicals in estrogen-induced carcinogenesis.

  title={8-Hydroxylation of guanine bases in kidney and liver DNA of hamsters treated with estradiol: role of free radicals in estrogen-induced carcinogenesis.},
  author={X Han and Joachim G. Liehr},
  journal={Cancer research},
  volume={54 21},
The chronic administration of estradiol induces a high incidence (80-100%) of renal tumors in male Syrian hamsters. As part of our examination of a mechanism of carcinogenesis by free radicals generated during redox cycling of catecholestrogen metabolites, we assayed levels of 8-hydroxy-2'-deoxyguanosine (8-OHdGua), a marker product of hydroxy radical interaction with DNA, in livers and kidneys of hamsters treated with estradiol. Injections of 50 and 100 mg/kg estradiol doubled renal 8-OHdGua… Expand
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  • Medicine, Biology
  • Endocrine reviews
  • 2000
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  • Mutation research
  • 1997
The increase of the 8-OH-dG level in the cellular DNA, detected by HPLC-ECD method, was supported by its immunochemical detection and its enhanced repair activity, and the validity of the general use of 8-Hydroxy-2'-deoxyguanosine as a marker of cellular oxidative stress is discussed. Expand
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Inhibition of Catechol O-Methyltransferase-catalyzed O-Methylation of 2- and 4-Hydroxyestradiol by Quercetin
  • B. Zhu, J. Liehr
  • Chemistry, Biology
  • The Journal of Biological Chemistry
  • 1996
The results suggest that the in vivo O-methylation of catecholestrogens is inhibited more by S-adenosyl-L-homocysteine than by quercetin, and the accumulation of 2- and 4-hydroxyestradiol during co-administration of estradiol and quERCetin may enhance metabolic redox cycling of ctcholestrogen and thusEstradiol-induced kidney tumorigenesis. Expand