Minireview: 16alpha-hydroxylated metabolites of dehydroepiandrosterone and their biological significance.

16alpha-Hydroxydehydroepiandrosterone is the precursor of fetal 16alpha-hydroxylated estrogens, the main phenolic steroids in pregnancy. For years their serum levels have been used as biochemical markers of well being of the fetus. In adults, however, increased levels of 16-hydroxylated estrogens were put in relation to the risk of cancer and, more recently, to some systemic autoimmune diseases. With respect to immunomodulatory effect of dehydroepiandrosterone and its metabolites, of which 7-hydroxysteroids formed by a concurrent reaction to 16-hydroxylation, are believed to be even the more immunoprotective species, it may be of interest, what is the true role of 16alpha-hydroxydehydroepiandrosterone and other 16-hydroxysteroids of 3beta-hydroxy-5-ene series. The present knowledge on the latter metabolite was summarized and discussed.