[Curcumin-induced the expression of inhibitor kappaBalpha protein in human prostate cancer cells].

OBJECTIVE: To investigate the curcumin-induced the expression of IkappaBalpha in androgen-dependent (LNCaP) and androgen-independent (PC3) prostate cancer cells, and to study the mechanisms of curcumin on the proliferative inhibition of prostate cancer cells.
METHODS: After LNCaP and PC3 cells were affected by 10, 25, 50, 75, 100 micromol/L curcumin respectively, the cell activity was assayed with methyl thiazolyl tetrazolium (MTT) method at 5, 12 and 24 hours; Flow cytometry was adopted to observe the cell cycle of LNCaP and PC3 cells at 24 hours. After 5 hours, the expression of IkappaBalpha in LNCaP and PC3 cells was observed with Western blotting.
RESULTS: Curcumin obviously suppressed the proliferation of LNCaP and PC3 cells in does-dependent and time-dependent manners. Curcumin could arrest the cell cycle of LNCaP and PC3 cells at G(2), M phase and then induce cell apoptosis. The expression of IkappaBalpha in LNCaP cells had no significant difference after using curcumin (F = 0.129, P > 0.05). However, the expression of IkappaBalpha in PC3 cells increased gradually with the inducement of concentration-increased curcumin (F = 31.618, P < 0.05).
CONCLUSIONS: IkappaBalpha may play a role in the curcumin inducing apoptosis of PC3 cell, while the curcumin inducing apoptosis of LNCaP cells is by antioxidation and inhibiting metabolites formation in LNCaP cells.