Limits to estrogen production by early and late preovulatory porcine follicles were assessed by comparing enzymatic capacities for androgen (17,20-lyase) and estrogen (aromatase) synthesis in theca interna and granulosa, support of enzyme activities by the redox partner proteins NADPH-cytochrome P450 oxidoreductase (reductase) and cytochrome b5, and tissue-specific expression and regulation of ...

Abstract: Aim: Breast cancer is one of the most common cancers among women, consistently elevated estrogen level in blood associated with persistently breast found many studies. The mechanisms carcinogenesis whereby involved conversion androgen to presence enzyme aromatase. Materials and Methods: Aromatase a (CYP19), cytochrome P450, which that synthesizes estrogen. expressed higher concentrati...

It is very important to examine the influence of inhibition of in situ estrogen production on the pathobiology of human sex steroid-dependent tumors in order to understand the clinical effects of aromatase inhibitors. We have examined the biological changes before and after aromatase inhibitor treatment in vitro (endometrial and ovarian cancer) and in vivo (breast cancer). First, we analyzed th...

Endocrine disrupting chemicals (EDCs) interfere with the biosynthesis, metabolism, and functions of steroid hormones, including estrogens and androgens. Aromatase enzyme converts androgen to estrogen. Thus, EDCs against aromatase significantly impact estrogen- and/or androgen-dependent functions, including the development of breast cancer. The current study aimed to develop a biologically relev...

The CYP19 gene encodes the enzyme aromatase, which plays a key role in the conversion of androgen to estrogen. The prostate is influenced by estrogen from peripheral sources as well as through aromatase activity in its stroma (1). There is evidence of elevated levels of aromatase activity and mRNA expression in stromal cells in prostate cancer as well as increasing evidence of cross-talk betwee...

OBJECTIVE Adipose tissue is an important extragonadal site for steroid hormone biosynthesis. After menopause, estrogens are synthesized exclusively in peripheral tissues from circulating steroid precursors, of which the most abundant is dehydroepiandrosterone sulfate (DHEAS). Our aim was to study activity of steroid sulfatase, an enzyme hydrolyzing DHEAS, and expression of steroid-converting en...

In humans, aromatase (CYP19) gene expression is regulated via alternative promoters. Activation of each promoter gives rise to a CYP19 mRNA species with a unique 5'-untranslated region. Inhibition of aromatase has been reported to downregulate lung tumor growth. The genetic basis for CYP19 gene expression and aromatase activity in lung cancer remains poorly understood. We analyzed tissues from ...

A finely tuned balance between estrogens and androgens controls reproductive functions, and the last step of steroidogenesis plays a key role in maintaining that balance. Environmental toxicants are a serious health concern, and numerous studies have been devoted to studying the effects of endocrine disrupting chemicals (EDCs). The effects of EDCs on steroidogenic enzymes may influence steroid ...

Over the last ten years, interpretation of presence vertebrate sex steroids in molluscs has changed dramatically. Evidence been accumulating that CYP11A and CYP19A genes (encoding cholesterol side-chain cleavage enzyme aromatase), are crucial for biosynthesis vertebrates, as well key functional steroid receptors, missing molluscan genomes. To provide further evidence, we sequenced whole transcr...