Consistently, the mRNA levels of LGR5 were also increased by treatment with 5-FU in both PDCs and PDTOs with wild-type p53 (Fig. 6c); however, 5-FU-induced activation of the WNT/β-catenin signaling pathway followed by CSC enrichment did not occur in the PDC harboring mutant p53 (Supplementary Fig. 6a, b) confirming the p53-dependent activation of CSCs by 5-FU treatment in CRC patient. This evidence concerns the gene LGR5 and colorectal carcinoma.