The 30% EtOH extracts of Ganoderma lucidum Fr. Karst (Ganodermateceae) showed weak 5alpha-reductase inhibitory activity and binding ability to androgen receptor. When LNCaP (lymph-node carcinoma of the prostate) cells were treated with the EtOH extracts, cell proliferation was inhibited. Treatment with the extracts significantly inhibited the testosterone-induced growth of the ventral prostate in castrated rats. These results showed that G. lucidum might be a useful ingredient in the treatment of androgen-induced diseases, such as benign prostatic hyperplasia or prostate cancer. From the 30% EtOH extracts, we isolated ganoderiol F, which showed binding activity to androgen receptor and inhibited LNCaP cell proliferation, as one of the active compounds in the 30% EtOH extracts 

The anti-androgenic activity of the ethanol extract of the fruiting body of Ganoderma lucidum has been previously reported. Ganoderol B with 5alpha-reductase inhibitory activity and the ability to bind to androgen receptor (AR) can inhibit androgen-induced LNCaP cell growth and suppress regrowth of the ventral prostate induced by testosterone in rats. The down-regulation of AR signaling by ganoderol B provides an important mechanism for its anti-androgenic activity. In view of the fact that PSA (prostatic specific antigen, a well-accepted prognostic indicator of prostate cancer) is down-regulated, an important implication of this study is that ganoderol B intervention strategy aimed at toning down the amplitude of androgen signaling could be helpful in controlling morbidity of prostate cancer. In conclusion, our result suggests that ganoderol B might be useful in prostate cancer and benign prostatic hyperplasia (BPH) therapy through suppressing the function of androgen and its receptor.