ISSN:
1573-7217
Keywords:
estrogen metabolism
;
breast cancer
;
catecholestrogen
;
estrone sulfatase
;
noncancerous tissue
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract In order to investigate the influence of estrogenmetabolism on human breast cancer, estradiol 2- and16α-hydroxylase (2- and 16α-OHase) activities were determined inthe microsomal fractions of cancer tissues by usingreverse phase HPLC. 2-OHase activity was detected inmost cancer tissues and noncancerous tissues, but theactivity was significantly lower in cancer tissues thanin the paired noncancerous tissues (0.01 〈 p〈 0.02). Interestingly the patients without lymph nodemetastasis had significantly higher 2-OHase activity in cancertissues than those with lymph node metastasis (0.02〈 p 〈 0.05). No correlation was observedbetween ER status and 2-OHase activity in cancertissues. On the other hand, 16α-OHase activity wasdetected only in one third of the breastcancer tissues examined. The activity was not significantlydifferent from that in noncancerous tissues, although itwas relatively higher in ER-positive cancer tissues whencompared with that in ER-negative ones (0.05 〈p 〈 0.1). Estrone sulfatase activity measured simultaneouslyin the cytosol fractions of some specimens wasmuch higher in cancer tissues than in noncanceroustissues (0.02 〈 p 〈 0.05). We found,however, no correlation between estrone sulfatase activity andestradiol hydroxylase activity. Taken together, our results suggestthat the increase in 2-OHase activity prevents theproliferation of breast cancer and that estradiol metabolismis regulated independently of the local biosynthesis ofestrogen.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/B:BREA.0000010495.08233.09
