An Electrochemical Outlook on Tamoxifen Biotransformation: Current and Future Prospects

Jorge      M.P.J. Garrido; E.      Manuela P.J. Garrido; Ana      Maria Oliveira-Brett; Fernanda      Borges

doi:10.2174/138920011795202965

Abstract

Tamoxifen is a nonsteroidal antiestrogen that is currently and widely used in the treatment of breast cancer in all of its stages, in adjuvant therapy as a long-term suppressant of tumor recurrence and also as a chemopreventive agent in women that are in high risk of developing this type of estrogen-dependent cancer. From a toxicological and (bio)analytical point of view the knowledge of the metabolic pathways of a drug is found to be extremely important. So, in the present work the most important tamoxifen biotransformation steps were reviewed in the light of recent pharmacological data. This overview also includes the current controversy concerning tamoxifen DNA-damaging (genotoxic) versus non-genotoxic mechanisms. A special focus will be given to the putative application of electrochemical methods as a modern and reliable analytical tool for determination of tamoxifen and its metabolites. Moreover, the potential of DNA electrochemical sensors for detection of structural damage to DNA as a basis for toxicity screening is highlighted. Future prospects looking for the importance of developing new analytical methodologies are also discussed.

Keywords: Biotransformation, breast cancer, DNA, electrochemistry, sensor, Tamoxifen, chemopreventive agent, genotoxic, Selective estrogen receptor modulators (SERMs), UDP-glucuronosyltransferase