Intratumoral androgen biosynthesis has been recognized as an essential factor of castration resistant prostate cancer. The present study investigated the effects of curcumin on the inhibition of intracrine androgen synthesis in prostate cancer. Human prostate cancer cell lines, LNCaP and 22Rv1 cells were incubated with or without curcumin after which cell proliferation was measured at 0 h, 24 h, 48 h, and 72 h, respectively. Prostate tissues from the transgenic adenocarcinoma of the mouse prostate (TRAMP) model were obtained after 1-month oral administration of 200 mg/kg/day curcumin. Testosterone and dihydrotestosterone concentrations in LNCaP prostate cancer cells were determined through LC-MS/MS assay. Curcumin inhibited cell proliferation and induced apoptosis of prostate cancer cells in a dose-dependent manner. Curcumin decreased the expression of steroidogenic acute regulatory proteins, CYP11A1 and HSD3B2 in prostate cancer cell lines, supporting the decrease of testosterone production. After one-month oral administration of curcumin, Aldo-Keto reductase 1C2 (AKR1C2) expression was elevated. Simultaneously, decreased testosterone levels in the prostate tissues were observed in the TRAMP mice. Meanwhile, curcumin treatments considerably increased the expression of AKR1C2 in prostate cancer cell lines, supporting the decrease of dihydrotestosterone. Taken together, these results suggest that curcumin's natural bioactive compounds could have potent anticancer properties due to suppression of androgen production, and this could have therapeutic effects on prostate cancer. This article is protected by copyright. All rights reserved.
Cancer science. 2018 Jan 25 [Epub ahead of print]
Hisamitsu Ide, Yan Lu, Takahiro Noguchi, Satoru Muto, Hiroshi Okada, Suguru Kawato, Shigeo Horie
Department of Urology, Dokkyo Medical University Saitama Medical Center, Saitama, Japan., Department of Urology, Juntendo University Graduate School of Medicine, Tokyo, Japan.