Isosilybin B, a flavonolignan isolated from silymarin, has anti-prostate cancer (PCA) activity via inhibiting proliferation and inducing G1 phase arrest and apoptosis. Isosilybin B causes androgen receptor (AR) degradation[1][2].
[1]. Deep G, et al. Isosilybin B and isosilybin A inhibit growth, induce G1 arrest and cause apoptosis in human prostatecancer LNCaP and 22Rv1 cells. Carcinogenesis. 2007 Jul;28(7):1533-42. [2]. Deep G, et al. Isosilybin B causes androgen receptor degradation in human prostate carcinoma cells via PI3K-Akt-Mdm2-mediated pathway. Oncogene. 2008 Jun 26;27(28):3986-98.