To assess the involvement of p53 in the 5-FU-induced activation of the WNT/β-catenin signaling pathway, we determined the effect of 5-FU on the WNT/β-catenin signaling pathway in HCT116 p53 wild-type (p53+/+), null (p53−/−), and mutant (p53R248W/−) isogenic human CRC cell lines. Here, TP53 is linked to colorectal carcinoma.