Despite hormone therapy is widely used (as both adjuvant and neoadjuvant therapy) for the treatment of estrogen receptor-positive (ER+) breast cancer and patients receiving hormone therapy often show satisfactory initial response, resistance to selective estrogen modulators and aromatase inhibitors is frequently found in patients after prolonged treatment. In this chapter, we will discuss the molecular mechanisms of action of various hormone therapy agents and the biology behind the induction of hormone therapy resistance in ER+ breast cancer cells. Recent development of novel agents that can be used to treat ER+ hormone therapy-resistant breast cancer will also be discussed in this chapter.
Part of the book: Estrogen