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The Impact of CYP2D6 Genotyping on Tamoxifen Treatment

Roberta Ferraldeschi1,2, William G Newman3

  • 1Department of Medical Oncology, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 4BX, UK. roberta.ferraldeschi@christie.nhs.uk.

Pharmaceuticals (Basel, Switzerland)
|October 8, 2016
PubMed

Insights

Tamoxifen treatment effectiveness for estrogen-receptor-positive breast cancer relies on its conversion to endoxifen by CYP2D6 enzymes. Genetic variations in CYP2D6 can impact treatment outcomes, influencing endoxifen levels and patient response.

Area of Science:

  • Pharmacogenomics
  • Oncology
  • Drug Metabolism

Background:

  • Tamoxifen is a vital treatment for estrogen-receptor-positive breast cancer.
  • Treatment efficacy hinges on its metabolism to the active endoxifen metabolite.
  • Cytochrome P450 2D6 (CYP2D6) is the primary enzyme responsible for this biotransformation.

Approach:

  • This review synthesizes existing research on the relationship between CYP2D6 genetic variants and tamoxifen efficacy.
  • It examines how germline genetic variations influence CYP2D6 enzyme activity.
  • The impact of altered enzyme activity on endoxifen concentrations and clinical outcomes is discussed.

Key Points:

  • CYP2D6 genetic polymorphisms can significantly affect tamoxifen's clinical effectiveness.
  • Environmental factors can also modulate CYP2D6 activity, impacting metabolite levels.
  • Understanding these genetic influences is crucial for personalized tamoxifen therapy.

Conclusions:

  • Germline variants in CYP2D6 are linked to variable patient responses to tamoxifen.
  • Further research into CYP2D6 pharmacogenetics can optimize breast cancer treatment strategies.
  • Personalized medicine approaches considering CYP2D6 genotype may improve tamoxifen therapy outcomes.
Keywords:
CYP2D6 genotypingbreast cancertamoxifen

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