Aromatase and Aromatase Inhibitors in Breast Cancer Treatment

Breast cancer is the most common cancer diagnosed in women, remains the second most common causes of death in women in the Western world. With advances in screening, diagnosis and treatment, the death rate for breast cancer patients has declined. Estrogens are responsible for the growth of hormone-dependant breast cancer. Regulation of estrogen biosynthesis is considered as a potential therapeutic strategy for the control of breast cancer. The enzyme aromatase catalyzes conversion of androgens into estrogens in the last step of estrogen biosynthesis. Inhibition of aromatase is adopted as an efficient approach for the prevention and treatment of breast cancer. Many steroidal and non steroidal aromatase inhibitors have been developed and are used clinically for breast cancer therapy. At present, two types of aromatase inhibitors, irreversible steroidal inhibitor and reversible nonsteroidal inhibitors are used in the treatment. Mostly, third-generation aromatase inhibitors are used as potent inhibitors of the aromatase enzyme, which catalyzes the conversion of androgen to estrogen which is the last step in estrogen biosynthesis. This review article aims to highlight about aromatase enzyme, its mechanism and aromatase inhibitors used in the treatment of breast cancer.

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