Figure 1From: Progesterone metabolites regulate induction, growth, and suppression of estrogen- and progesterone receptor-negative human breast cell tumorsConversion of progesterone to 3α-dihydroprogesterone (3αHP) and 5α-dihydroprogesterone (5αP). In vitro studies have shown that both ER/PR-positive and -negative human breast tissues and cell lines are able to convert progesterone to 3αHP and 5αP by the actions of 3α-hydroxysteroid oxidoreductase (3α-HSO) and 5α-reductase, respectively.Back to article page