Background: The modulatory effects and molecular mechanisms of curcumin (CCM) on the cytotoxicity of chemotherapeutic agents to prostate cancer cells were explored.
Methods: The combined effects of CCM and chemotherapeutic agents were examined by three different administration schedules (one concurrent and two sequential treatments) in two androgen-independent prostate cancer (AIPC) cells (PC-3 and DU145). Alteration of cell cycle progression, protein levels, and transcriptional activation in PC-3 cells were assayed by flow cytometry, Western blotting, and gel shift assay, respectively.
Results: The combined effects of CCM --> chemotherapeutic agent schedule showed the greatest synergistic cytotoxicity when compared to the other two schedules in both cells. CCM induced a significant G1 arrest in PC-3, which may be mediated by the induction of p21(WAF1/CIP1) and C/EBPbeta. Moreover, CCM was able to inhibit both the constitutional and TNF-alpha-induced NF-kappaB activation in a time-dependent manner.
Conclusions: The incorporation of CCM into cytotoxic therapies may be a promising strategy for the treatment of AIPC.
Copyright 2002 Wiley-Liss, Inc.