Expression of p21, Bcl-2, Bclx, and c-Myc mRNAs in tumor-adjacent tissue of colon in PXR-humanized (hPXR), wild-type (WT), and Pxr-null mice with or without rifaximin (RIFax) treatment in AOM/DSS-induced colon carcinogenesis [n = 5 for AOM/DSS and AOM/DSS-rifaximin group, n = 4 for normal control (Con) group]. #P < 0.05 compared with control (normal tissue); *P < 0.05 compared with AOM/DSS-treated group.