Toxicity and adverse effects of Tamoxifen and other anti-estrogen drugs

Abstract

Breast cancer is a heterogeneous disease affecting thousands of people every year. Multiple factors are responsible in causing breast cancer while a number of treatment options are also available for the disease. Tamoxifen is the most widely used anti-estrogen for the treatment of hormone-dependent breast cancer. The specific drug is used as a hormonal therapy for patients who exhibit estrogen receptor positive breast cancer. The pharmacological activity of Tamoxifen is dependent on its conversion to its active metabolite, endoxifen, by CYP2D6. Tamoxifen reduces the risk of recurrence and death from breast cancer when given as adjuvant therapy and provides effective palliation for patients with metastatic breast cancer. In this review we focus on the role of Tamoxifen in breast cancer treatment including mechanisms and side-effects. Finally, we discuss in detail the exciting prospects that lie ahead.

Keywords: AF-1; Activation function-1; Anti-estrogen therapy; BCPT; BMI; Body Mass Index; Breast Cancer Prevention Trial; Breast cancer; DBD; DNA damage; DNA-binding domain; EGF receptors; EGFR; ER; EREs; Estrogen receptor; Estrogen response elements; FDA; Food and Drug administration; HATs; HDACs; HER2; HR; Histone acetyltransferases; Histone deacetylases; Homologous recombination; Human epidermal growth factor receptor 2; ICI; Imperial Chemical Industries; LBD; Ligand-binding domain; NSABP; National Surgical Adjuvant Breast and Bowel Project; Oxidative stress; PR; Progesterone receptor; RNS; ROS; Reactive nitrogen species; Reactive oxygen species; SERM; Selective Estrogen Receptor Modulator; TAM; TOR; Tamoxifen; Torimefene.