Oestrogen production in adipose tissue from normal women and women with endometrial cancer in vitro.

The in vitro conversion of androstenedione to oestrone and oestrone to oestradiol was investigated in human adipose tissue. Higher rates of oestrone (range 1.2-44.0 pg/mg protein/3h) and oestradiol (range 0.6-15.2 ng/mg protein/h) production were observed in tissue samples obtained from women aged 40-50 years compared with the rates measured using adipose tissue from younger women (range 0.7-7.7 pg oestrone/mg protein/3 h and 0.4-1.8 ng oestradiol/mg protein/h). Five subjects studied with endometrial cancer did not show a market increase in conversion of androstenedione to oestrone or oestrone to oestradiol in subcutaneous adipose tissue compared with normal women of similar age and weight. A sample of omental adipose tissue from one subject with endometrial cancer did show a high conversion rate of androstenedione to oestrone (104.0 pg oestrone/mg protein/3 h), although the rate of conversion of oestrone to oestradiol was lower than that observed in subcutaneous adipose tissue, indicating that steroid metabolism is not uniform in adipose tissue throughout the body.