To further investigate whether p53 plays an important role on BV-induced cell growth inhibition and up-regulation of DR4 and DR5, we pretreated HCT116 and SW480 colon cancer cells with 20 μM pifithrin-α, a p53 inhibitor for 1 h, and then these cells were treated with BV (2 μg/ml) for 24 h to assess cell viability and DR4 and DR5 expression. This evidence concerns the gene TP53 and malignant colon neoplasm.