The present disclosure demonstrates the molecular effects of glyceollins on human prostate cancer cell LNCaP to further elucidate its potential effects on prostate cancer prevention. The glyceollins inhibited LNCaP cell growth similar to that of the soy isoflavone genistein. The growth inhibitory effects of the glyceollins appeared to be due to an inhibition on G1/S progression and correlated with an up-regulation of cyclin-dependent kinase inhibitor A1 and B1 mRNA and protein levels. By contrast, genistein only up-regulates cyclin-dependent kinase inhibitor A1. In addition, glyceollin treatments led to down-regulated mRNA levels for androgen responsive genes. In contrast to genistein, this effect of glyceollins on androgen responsive genes appeared to be mediated through modulation of an estrogen- but not androgen-mediated pathway. Hence, the glyceollins exerted multiple effects on LNCaP cells that may be considered cancer preventive and the mechanisms of action appeared to be different from other soy-derived phytochemicals.