EGCG worked synergistically with the COX-2 inhibitor NS398 to: (a) arrest cell growth; (b) induce apoptosis by altering the Bax/Bcl-2 ratio and increasing pro-caspase-6 and -9 expression and PARP cleavage; (c) suppress expression of peroxisome proliferator activated receptor-γ (PPAR-γ); and (d) suppress activation of NF-κB in multiple human prostate cancer cell lines in vitro. The gene discussed is PTGS2; the disease is prostate cancer.