Estradiol inhibits the estrone sulfatase activity in normal and cancerous human breast tissues

Recent insight on the control of enzymes involved in estrogen formation and transformation in human breast cancer

“…Using total breast cancer tissues from postmenopausal patients, it was demonstrated that nomegestrol acetate [110] or medrogestone could block the sulfatase activity. The effect was significantly more active in breast carcinoma than in the area of the breast considered as normal (Table 1).…”

Inhibition of aromatase activity in MCF-7aro human breast cancer cells by the natural androgens testosterone and androstenedione

“…In previous studies, we demonstrated that E 2 can control its metabolic formation by regulating the sulfatase and aromatase enzymes in breast cancer cells and tissues (10,39,40). The IC 50 values were 8.77=10 -10 and 8.55=10 -8 mol/ L, respectively.…”

Nomegestrol acetate is an anti-aromatase agent in human MCF-7aro breast cancer cells

“…In previous studies, we demonstrated that nomegestrol acetate possesses a global beneficial effect on the enzymes involved in estrogen biosynthesis and metabolism; NOMAC can inhibit estrone sulfatase (19,46), 17b-HSD type 1 (19), or stimulate sulfotransferase (47,48) activities using hormone-dependent breast cancer cells or total breast cancer tissue. But, data on the regulation of aromatase activity by progestogens are very sparse.…”

“…However, aromatase cytochrome P450 is a multi-enzymatic complex with many potential regulation sites at genomic and/or enzymatic activity levels. In previous studies, we demonstrated that the estrogen E 2 can regulate its own bioformation (product inhibition) by blocking the sulfatase and aromatase pathways (58)(59)(60), whereas the natural androgens androstenedione and testosterone act not only as substrate but also as inhibitors of the aromatase in MCF-7aro cells (61). Moreover, the 20a-dihydroprogesterone, a progesterone metabolite, can be selectively implicated in the control of aromatase activity (51,62).…”