anastrozole brands

Molecular formula: C17H19N5

Anastrazole exerts its anti-estrogenic effects via selective and competitive inhibition of the aromatase enzyme found predominantly in the adrenal glands, liver, and fatty tissues. Many breast cancers are hormone receptor-positive, meaning their growth is stimulated and/or maintained by the presence of hormones such as estrogen or progesterone. In postmenopausal women, estrogen is primarily derived from the conversion of adrenally-produced androgens into estrogens by the aromatase enzyme - by competitively inhibiting the biosynthesis of estrogen at these enzymes, anastrozole effectively suppresses circulating estrogen levels and, subsequently, the growth of hormone receptor-positive tumours. Anastrozole is a nonsteroidal aromatase inhibitor that interferes with estradiol production in peripheral tissues. Adrenally generated androstenedione, the chief source of circulating estrogen in postmenopausal women, is converted by aromatase to estrone, which is further converted to estradiol. Growth of many breast cancer tumors containing estrogen receptors and aromatase can be promoted by estrogen. Anastrozole is a potent and selective non-steroidal aromatase inhibitor. It significantly lowers serum estradiol concentrations and has no detectable effect on formation of adrenal corticosteroids or aldosterone. Because estrogen acts as a growth factor for hormone-dependent breast cancer cells, anastrozole-induced reduction of serum and tumor concentrations of estrogen inhibits tumor growth and delays disease progression. Anastrozole selectively inhibits the conversion of androgens to estrogens. In postmenopausal women, ovarian secretion of estrogen declines and conversion of adrenal androgens (mainly androstenedione and testosterone) to estrone and estradiol in peripheral tissues (adipose, muscle, and liver), catalyzed by the aromatase enzyme, is the principal source of estrogens. Anastrozole inhibits the aromatase enzyme by competitively binding to the heme of the cytochrome P-450 unit of the enzyme; suppression of estrogen biosynthesis in all tissues reduces serum concentrations of circulating estrogens, including estrone, estradiol, and estrone sulfate. Anastrozole selectively inhibits synthesis of estrogens and does not affect synthesis of adrenal corticosteroid, aldosterone, or thyroid hormone. In animals, anastrozole has not been shown to possess direct progestogenic, androgenic, or estrogenic activity, but alterations in the circulating concentrations of progesterone, androgens, and estrogens have been observed.

Source: PubChem (NCBI) · compound 2187