PKD1 and prostate cancer: In order to determine if curcumin can modulate the expression or activity of PKD1, androgen-independent prostate cancer C4-2 cells were treated with curcumin for varying time points, and the expression of total PKD1 (Figure 2A) and active PKD1 (Figure 2B) was determined using PKD1 and phospho PKD1 antibody antibodies.