Raeside J I, Christie H L, Forster L, Renaud R L
Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Biochem Biophys Res Commun. 2000 Jul 5;273(2):505-8. doi: 10.1006/bbrc.2000.2984.
Estrogen sulfatase and sulfotransferase (EST) activities are present in breast cancer tissues but there are no reports on EST in cancerous bone cells. We incubated [(3)H]estradiol-17beta with cells from a canine osteosarcoma D17 line for periods up to 24 h. Radioactive steroids were recovered from the media and separated into unconjugated and conjugated fractions using Sep-Pak C18 cartridges. The conjugate fraction was solvolyzed and the resulting free steroids were obtained from a second C18 cartridge. Little metabolism 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 were recovered as sulfates in all three experiments. HPLC profiles showed a limited metabolism of estradiol to other compounds except for estrone, which was clearly present in both free and sulfate fractions. These results suggest that EST may have a role in the local metabolism of estrogens in bone.
雌激素硫酸酯酶和磺基转移酶（EST）活性存在于乳腺癌组织中，但尚无关于癌性骨细胞中EST的报道。我们将[³H]雌二醇-17β与犬骨肉瘤D17细胞系的细胞孵育长达24小时。从培养基中回收放射性类固醇，并使用Sep-Pak C18柱将其分离为未结合和结合部分。结合部分进行溶剂解，从第二个C18柱中获得产生的游离类固醇。孵育4小时时几乎没有明显的代谢，但到24小时时，结合部分中可见多达一半的放射性。在所有三个实验中，大多数结合物以硫酸盐形式回收。高效液相色谱图显示，除雌酮外，雌二醇向其他化合物的代谢有限，雌酮在游离和硫酸盐部分均明显存在。这些结果表明，EST可能在骨中雌激素的局部代谢中起作用。
