These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Steroid sulphotransferase and 17beta-hydroxysteroid dehydrogenase activities in Ishikawa human endometrial adenocarcinoma cells.
    Author: Chetrite G, Pasqualini JR.
    Journal: J Steroid Biochem Mol Biol; 1997 Apr; 61(1-2):27-34. PubMed ID: 9328207.
    Abstract:
    The present studies concern sulphotransferase activities for estrogens and other steroids, and 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activities for estrogens in Ishikawa endometrial adenocarcinoma cells. When physiological concentrations of various estrogens (estrone, estradiol, estriol) are incubated, most of the transformation product is the respective sulphate. The sulphotransferase activity is very rapid, and 2 h after incubation 70-95% are converted to the sulphated form. Sulphates are found exclusively in the culture medium, which suggests that as soon as the sulphate is biosynthesized it is secreted to the medium. Comparative data using neutral steroids (dehydroepiandrosterone, testosterone, and pregnenolone) show that sulphotransferase activity for these compounds is very limited. In another series of studies, 17beta-HSD activity was explored for the interconversion estrone estradiol. At low concentrations (5 x 10(-9)-5 x 10(-8) M), when estradiol (E2) is incubated, most of the unconjugated material remains as E2 in the cellular compartment, but at high concentrations (5 x 10(-7)-5 x 10(-6) M) a great proportion (70-80%) of the E2 is converted to estrone (E1). On the other hand, after incubation of E1 at all concentrations most remained as unchanged E1. It is suggested that, in Ishikawa cells, at very low concentrations of E1 or E2, sulphotransferases are predominant, but when this enzyme is saturated 17beta-HSD activity is orientated to the oxidative form.
    [Abstract] [Full Text] [Related] [New Search]