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Steroid sulfate-sulfatases in the human benign prostatic hyperplasia -BPH-

: Molwitz, T.; Bartsch, W.; Voigt, K.-D.

Journal of steroid biochemistry 25 (1986), No.25, Supplement
ISSN: 0022-4731
International Congress on Hormonal Steroids <7, 1986, Madrid>
Conference Paper
Fraunhofer ITA ( ITEM) ()
benign prostatic hyperplasia; Steroid sulfate-sulfatase

Estrone sulfate-sulfohydrolase (E1S) and dehydroepiandrosterone sulfate-sulfohydrolase (DHEAS-S) were studied in epithelial and stromal cells of 7 human BPHs. The epithelial cells were mechanically separated from the stroma by standard techniques using soft homogenization and filtration through 150 myM polyvenylgaze. Both tissue fractions were incubated with tritium labelled steroid sulfates in Tris-buffer, the formed free steroids were extracted with ether and than quantified by liquid scintillation. E1S-S and DHEAS-S assays were optimised with regard to pH, incubation time, substrate and enzyme concentrations and co-factor. We found a pH-optimum of 7.0+-0.5 (SEM) for both enzymes. Neither E1S-S nor DHEAS-S need NADH or NADPH as co-factor. Km and Vmax values were 6.3 myM+-3.2myM (SEM); n=7; and 377.9+-269 (SEM) myM/h x mg DNA for E1S-S and 3.9+-1.1 myM (SEM);n=5; and 55.3+-20.6 (SEM) myM/h x mg DNA; n=5; for DHEAS-S respectively. The highest enzyme activities were found in the nuclei of the epithelial cells, while the stroma did not show significant activities. DHEAS was found to be a competitive inhibitor of E1S-S (Ki=4.0+-0.82 myM (SEM) and DHEAS-S was competitively inhibited by E1S (Ki=2.7myM+-0.54myM (SEM); n=4;). The high sulfatase activities in the epithelial cells suggests their capacity of E1 and DHEAS mobilisation from the large plasma pools of both steroid sulfates. (ITA)