A complementary DNA (cDNA) copy of the aromatase P-450 has been isolated from a chicken ovary library using as probe a partial cDNA believed to encode the human placental aromatase. The predicted amino acid sequence of the chicken aromatase cDNA possesses regions of homology to that of its human counterpart, but only limited homology to other cytochrome P-450 enzymes. The introduction of the cD...

The aromatase inhibitors deplete oestrogen by inhibiting aromatase, the enzyme that synthesises oestrogen from androgens. They are effective as therapies for breast cancer only in postmenopausal women whose tumours express oestrogen or progesterone receptors. As adjuvant therapy, tamoxifen and the aromatase inhibitors have similar efficacy in the first 5 years of treatment. Aromatase inhibitors...

Use of steroid biosynthesis inhibitors to suppress estrogen production is a logical strategy in the treatment of women with hormone-dependent breast cancer. The clinical availability of aminoglutethimide as an inhibitor of cytochrome P-450-mediated steroid hydroxylations prompted study of the precise pharmacological and biochemical effects of this drug. Pharmacokinetic studies revealed that ami...

Aromatase is a key enzyme in intratumoral estrogen production required for the production of estrogens through the conversion of serum androgens in postmenopausal breast cancer patients. There have been, however, controversies regarding the intratumoral localization of aromatase in human breast carcinoma tissues. Therefore, we have first examined the intratumoral localization of aromatase mRNA/...

The pituitary gland is part of hypothalamic-pituitary-gonadal axis, which controls development, reproduction, and aging in humans and animals. In addition, the pituitary gland is regulated mainly by hormones and neurotransmitters released from the hypothalamus and by systemic hormones secreted by target glands. Aromatase P450, the enzyme responsible for the catabolization of aromatizable androg...

Biochemical and molecular genetic studies were made on a case of placental aromatase (P-450AROM) deficiency. Of the enzymes participating in the electron transport system of placental microsomes, only aromatase activity was decreased specifically in the patient, being less than 0.3% of the normal activity. Northern and Western blotting analyses showed that the transcription of the aromatase gen...

In the diamondback terrapin, Malaclemys terrapin, males hatch at incubation temperatures below 28 degrees C whereas females hatch at temperatures above 30 degrees C. When estrogen is applied to the eggs at male temperatures early in development, females are produced. These data suggest that the enzyme necessary for estrogen synthesis (CYP19, aromatase) in the developing gonad plays a critical r...