The trial designs were generally similar. Arimidex-Nolvadex (ARNO) 95 trial included 979 women who were randomly assigned after 2 years of tamoxifen to either 3 additional years of tamoxifen or 3 years of anastrozole. The Italian Tamoxifen Arimidex (ITA) trial included 448 women who were randomly assigned after 2 – 3 years on tamoxifen to either tamoxifen or anastrozole for 2 – 3 years. In the ...

The extragonadal synthesis of biological active steroid hormones from their inactive precursors in target tissues is named "intracrinology." Of particular importance for the progression of estrogen-dependent cancers is the in situ formation of the biological most active estrogen, 17beta-estradiol (E2). In cancer cells, conversion of inactive steroid hormone precursors to E2 is accomplished from...

7or-(4'-Amino)phenylthio-l,4-androstadiene-3,17-dione(7a-APTADD), a potent enzyme-activated irreversible inhibitor, was examined in two different human cell culture lines, MCF-7 human mammary carcinoma cells and JAr choriocarcinoma cells. Both the MCF-7 and JAr cell culture systems exhibit aromatase activity, and 7a-APTADD was evaluated for its aromatase-inhibitory activity, for its ability to ...

The article presents a clinical case illustrating the effectiveness of abemaciclib in combination with anastrozole metastatic estrogen receptor-positive HER2/neu-negative breast cancer (BC). CDK4/6 inhibitors have changed paradigm treatment patients hormone-positive HER2 BC. Thanks to ability palbociclib, ribociclib and delay overcome resistance endocrine therapy, not only newly diagnosed disea...

letrozole is a synthetic aromatase inhibitor and interfere in the committed step in the synthesis of endogenous estrogens from androgens. also estrogens regulate the immune system in teleost. changes of 17- β- esrtradiol (e 2 ), serum immunoglobulin and lysozyme levels were measured using a method based on the ability of lysozyme to lyse the bacterium micrococcus lysodeikticus , enzyme-linked i...

Aromatase is the enzyme synthesizing estrogens from androgens. In estrogen-dependent breast tumors, estrogens induce the expression of growth factors responsible for cancer cell proliferation. In situ estrogen synthesis by aromatase "is thought to play a key role in the promotion of breast cancer growth. Aromatase inhibitors (AIs) provide new approaches for the prevention and treatment of breas...

Cyclooxygenase-2 (COX-2) inhibitor nimesulide derivatives compounds A and B decreased aromatase activity in breast cancer cells via a novel mechanism different to aromatase inhibitors (AIs), and were defined as "aromatase suppressors". Breast carcinoma cells (MCF-7aro and T47Daro) transfected with aromatase full gene were used to explore the mechanisms of the two compounds. They dose and time-d...

The local regulation of ovarian aromatase enzyme in polycystic ovary syndrome (PCOS) was studied with aromatase conversion and [11C]vorozole-binding assays to analyze aromatase activity, substrate-enzyme affinity and number of aromatase binding sites in non-cultured human granulosa cells (GC) incubated with different sources and preparations of follicular fluid (FF). Incubation with FF from wom...

Breast cancer is the most common global malignancy and leading cause of deaths for women. Aromatase inhibitors are clinically recommended therapy disorders. However, resistance to aromatase therapies still occurs underlined molecular mechanisms poorly understood. The tumour specimens consisted inhibitor-sensitive inhibitor-resistant breast patients, who were compared differentially expressed ge...

Androgens are transformed into aromatic estrogens by CYP450 aromatase in a three-step reaction consuming three equivalents of oxygen and three equivalents of NADPH. Estrogens are substrates for nuclear estrogen receptors (ERs) and play a key role in estrogen-dependent tumour cell formation and proliferation. Natural phytoestrogens are proved to be competitive inhibitors of aromatase enzyme at I...