In order to investigate the effect of 5-FU on the expression of TLR4 in colorectal cancer cells and to address the differences between TLR4 variants, HCT116 cell line transfected with different TLR4 genotypes were treated at different concentrations of 5-FU (0, 125, 625 μg/mL) in the presence and absence of LPS (1 μg/mL for 24 h). The gene discussed is TLR4; the disease is colorectal cancer.