Steroid sulfation Current concepts.

Formation of steroid sulfates is catalyzed by sulfotransferase enzymes that are widely distributed and frequently of high specificity. Steroid sulfates cannot be described as being active hormones, but some serve in tissue sites as precursors of active steroids formed by enzymic cleavage of the sulfate group by sulfatase enzymes. There is increasing evidence that intracellular sulfation and desulfation can play a role in regulating the availability of active steroid hormones near target sites. There are strong indications for this regulation in the uterine compartment, in the liver, and in mammary cancer cells.