Figure 3.

Oldhamianoside II functions as a negative regulator of Wnt/β-catenin signaling and promotes β-catenin degradation in prostate cancer cells. (A) Total protein or (B) nuclear fractions from VCaP cells were analyzed by western blotting. The mRNA and protein levels of β-catenin target genes, (C and D) cyclin D1 (CCND1) and (E and F) c-Jun, in VCaP cells are shown. (G) In the presence or absence of MG132 (30 µM), western blotting was performed to detect the expression of β-catenin and cyclin D1 in VCaP cells treated with or without oldhamianoside II (100 µg/l). (H) Following stimulation with CHX (50 µg/ml) for 6 h, VCaP cells were treated with oldhamianoside II (100 µg/l) or its vehicle control for an additional 24 h. Extracted total protein samples at the indicated time points were subjected to western blotting. Data are presented as the mean ± standard deviation of three independent experiments. *P<0.05 and **P<0.01 vs. vehicle control. CCND1, cyclin D1; CHX, cycloheximide.