Hormone Therapy for Prostate Cancer (Fact Sheet)
Androgens are required for normal growth and function of the prostate.
What are male sex hormones?
Hormones are substances made by glands in the body that function as chemical signals. They affect the actions of cells and tissues at various locations in the body, often reaching their targets by traveling through the bloodstream.
Androgens (male sex hormones) are a class of hormones that control the development and maintenance of male characteristics. Testosterone and dihydrotestosterone (DHT) are the most abundant androgens in men. Almost all testosterone is produced in the testicles; a small amount is produced by the adrenal glands. Prostate cancer cells may also have the ability to produce testosterone.
How do hormones stimulate the growth of prostate cancer?
Androgens are required for normal growth and function of the prostate, a gland in the male reproductive system that helps make semen. Androgens are also necessary for prostate cancers to grow. Androgens promote the growth of both normal and cancerous prostate cells by binding to and activating the androgen receptor, a protein that is expressed in prostate cells.1 Once activated, the androgen receptor stimulates the expression of specific genes that cause prostate cells to grow.2
Early in their development, prostate cancers need relatively high levels of androgens to grow. Such prostate cancers are referred to as androgen dependent or androgen sensitive because treatments that decrease androgen levels or block androgen activity can inhibit their growth.
Most prostate cancers eventually become "castration resistant," which means that they can continue to grow even when androgen levels in the body are extremely low or undetectable.