A report on Estrogen receptor and Aromatase

A dimer of the ligand-binding region of ERβ (PDB rendering based on ).
The domain structures of ERα and ERβ, including some of the known phosphorylation sites involved in ligand-independent regulation.
A dimer of the ligand-binding region of ERα (PDB rendering based on ).
Nolvadex (tamoxifen) 20 mg
Arimidex (anastrozole) 1 mg

Aromatase inhibitors, which stop the production of estrogen in postmenopausal women, have become useful in the management of patients with breast cancer whose lesion was found to be estrogen receptor positive.

- Aromatase

A dramatic demonstration of the importance of estrogens in the regulation of fat deposition comes from transgenic mice that were genetically engineered to lack a functional aromatase gene.

- Estrogen receptor
A dimer of the ligand-binding region of ERβ (PDB rendering based on ).

5 related topics with Alpha

Overall
Estradiol, the major estrogen sex hormone in humans and a widely used medication.

Estrogen

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Category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics.

Category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics.

Estradiol, the major estrogen sex hormone in humans and a widely used medication.
Reference ranges for the blood content of estradiol, the primary type of estrogen, during the menstrual cycle.
Steroidogenesis, showing estrogens at bottom right as in pink triangle.

Once inside the cell, they bind to and activate estrogen receptors (ERs) which in turn modulate the expression of many genes.

All of the different forms of estrogen are synthesized from androgens, specifically testosterone and androstenedione, by the enzyme aromatase.

Human steroidogenesis, showing estradiol at bottom right.

Estradiol

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Estrogen steroid hormone and the major female sex hormone.

Estrogen steroid hormone and the major female sex hormone.

Human steroidogenesis, showing estradiol at bottom right.
Estradiol levels across the menstrual cycle in 36 normally cycling, ovulatory women, based on 956 specimens. The horizontal dashed lines are the mean integrated levels for each curve. The vertical dashed line in the center is mid-cycle.

The major pathway involves the formation of androstenedione, which is then converted by aromatase into estrone and is subsequently converted into estradiol.

The estrogen receptor, as well as the progesterone receptor, have been detected in the skin, including in keratinocytes and fibroblasts.

Comprehensive overview of steroidogenesis, showing estrone on the lower right among the estrogens.

Estrone

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Steroid, a weak estrogen, and a minor female sex hormone.

Steroid, a weak estrogen, and a minor female sex hormone.

Comprehensive overview of steroidogenesis, showing estrone on the lower right among the estrogens.

Estrone is an estrogen, specifically an agonist of the estrogen receptors ERα and ERβ.

The principal pathway involves androstenedione as an intermediate, with androstenedione being transformed into estrone by the enzyme aromatase.

Anastrozole, a non steroidal aromatase inhibitor and a widely used drug in the treatment of breast cancer.

Aromatase inhibitor

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Aromatase inhibitors (AIs) are a class of drugs used in the treatment of breast cancer in postmenopausal women and in men, and gynecomastia in men.

Aromatase inhibitors (AIs) are a class of drugs used in the treatment of breast cancer in postmenopausal women and in men, and gynecomastia in men.

Anastrozole, a non steroidal aromatase inhibitor and a widely used drug in the treatment of breast cancer.
Often used as a cancer treatment in postmenopausal women, AIs work by blocking the conversion of androstenedione and testosterone into estrone and estradiol, respectively, which are both crucial to the growth of developing breast cancers (AIs are also effective at treating ovarian cancer, but less commonly so). In the diagram, the adrenal gland (1) releases androstenedione (3) while the ovaries (2) secrete testosterone (4). Both hormones travel to peripheral tissues or a breast cell (5), where they would be converted into estrone (8) or estradiol (9) if not for AIs (7), which prevent the enzyme CYP19A1 (also known as aromatase or estrogen synthase) (6) from catalyzing the reaction that turns androstenedione and testosterone into estrone and estradiol. In the diagram, Part A represents the successful conversion of androstenedione and testosterone into estrone and estradiol in the liver. Part B represents the blockage of this conversion by aromatase inhibitors both in peripheral tissues and in the breast tumor itself.
Arimidex (anastrozole) 1 mg tablets

Aromatase is the enzyme that catalyzes a key aromatization step in the synthesis of estrogen.

Tamoxifen (a SERM) traditionally was the drug treatment of choice, but the ATAC trial (Arimidex, Tamoxifen, Alone or in Combination) showed that in women with localized estrogen receptor-positive breast cancer, women receiving the AI anastrozole had better results than the tamoxifen group.

Anastrozole

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Medication used in addition to other treatments for breast cancer.

Medication used in addition to other treatments for breast cancer.

The trial suggested that anastrozole is the preferred medical therapy for postmenopausal women with localized estrogen receptor-positive breast cancer.

Anastrozole works by reversibly binding to the aromatase enzyme, and through competitive inhibition blocks the conversion of androgens to estrogens in peripheral (extragonadal) tissues.