Estrogen sulfatase and sulfotransferase (EST) activities are present in bre
ast cancer tissues but there are no reports on EST in cancerous bone cells,
We incubated [H-3]estradiol-17 beta with cells from a canine osteosarcoma
D17 line for periods up to 24 h, Radioactive steroids were recovered from t
he media and separated into unconjugated and conjugated fractions using Sep
-Pak C18 cartridges. The conjugate fraction was solvolyzed and the resultin
g free steroids were obtained from a second C18 cartridge. Little metabolis
m was apparent in 4 h of incubation, but by 24 h as much as one half of the
radioactivity was seen in the conjugate fraction. Most of the conjugates w
ere recovered as sulfates in all three experiments. HPLC profiles showed a
limited metabolism of estradiol to other compounds except for estrone, whic
h was clearly present in both free and sulfate fractions. These results sug
gest that EST may have a role in the local metabolism Of estrogens in bone,
(C) 2000 Academic Press.