BACKGROUND The optimal ways of using aromatase inhibitors or tamoxifen as endocrine treatment for early breast cancer remains uncertain. METHODS We undertook meta-analyses of individual data on 31,920 postmenopausal women with oestrogen-receptor-positive early breast cancer in the randomised trials of 5 years of aromatase inhibitor versus 5 years of tamoxifen; of 5 years of aromatase inhibito...

The mammalian testis serves two main functions: production of spermatozoa and synthesis of steroids; among them, estrogens are the end products obtained from the irreversible transformation of androgens by aromatase. The aromatase is encoded by a single gene (cyp19) in humans which contains 18 exons, 9 of them being translated. In rat the aromatase activity is mainly located in Sertoli cells of...

Most breast cancers at diagnosis are estrogen receptor-positive (ERþ) and depend on estrogen for growth and survival. Blocking estrogen biosynthesis by aromatase inhibitors has therefore become a first-line endocrine therapy for postmenopausal women with ERþ breast cancers. Despite providing substantial improvements in patient outcome, aromatase inhibitor resistance remains amajor clinical chal...

Aromatase, a key steroidogenic enzyme that catalyses the conversion of androgens to estrogens, represent a target for endocrine disrupting chemicals. However, little is known about the effect of pollutants on aromatase enzymes in fish. In this study, we first optimized a rainbow trout (Oncorhynchus mykiss) microsomal aromatase assay to measure the effects of 43 substances belonging to diverse c...

Epidemiologic studies have implicated estrogenic exposure as well as human papilloma virus (HPV) infection in cervical carcinogenesis, and some studies have suggested that estrogen and HPV may play synergistic roles in cervical tumorigenesis. In this study, we report a novel finding that approximately 35% of cervical carcinomas tested (n = 19) express aromatase, the enzyme responsible for conve...

Inhibition of aromatase (CYTP450) as a key enzyme in the estrogen biosynthesis could result in regression of estrogen-dependent tumors and even preventing the promotion of breast cancer. Although today potent steroid and non-steroid inhibitors of aromatase are available, isoflavanone derivatives as natural compounds with least side effects have been described as the candidate for a new generati...

orally active aromatase inhibitors (ais) have gained attention for treatment of infertile women with endometriosis in whom aromatase p450 is aberrantly expressed. this review aimed to critically appraise and summarize the available evidence concerning the use of ais for management of endometriosis-associated infertility. pubmed was searched to may 2015 with the following key words: endometriosi...

n engl j med 360;18 nejm.org april 30, 2009 1912 sions,2 and we also did not detect aromatase protein in the glandular and stromal compartments of ectopic endometrial tissue. We recently found that what was believed to be aromatase protein was mainly endogenous biotin labeling or iron deposits.3 Using three different protocols, we found only barely detectable amounts of aromatase messenger RNA ...

Sex determination in egg-laying amniotes may be fundamentally different from that of placental mammals. The mammalian ovary differentiates normally in the absence of estrogen, whereas estrogen seems to be crucial for proper ovarian development in birds, reptiles, and lower vertebrates. Estrogens are produced normally by the biosynthetic conversion of androgens by the enzyme aromatase (CYP19), w...

Endocrine disruptors are hormone mimics that modify hormonal action in humans and animals. It is thought that some endocrine disruptors modify estrogen and androgen action in humans and animals by suppressing aromatase activity. Aromatase cytochrome P450 is the key enzyme that converts C19 androgens to aromatic C18 estrogenic steroids. We have developed a novel aromatase inhibitor screening met...