The quantification of p-IKKα/β and PCNA-positive cells in PC-3 tumor sections showed that oral intake of apigenin at both doses (20 and 50 μg) results in 57% and 70% (P < 0.001) decrease in IKKα/β phosphorylation and 56% (P < 0.001) and 86% (P < 0.001) decrease in proliferation index compared with control group. This evidence concerns the gene PCNA and neoplasm.