TYMS and colorectal carcinoma: First, to elucidatethe relationship between 5-FU resistance and TYMS expression, we analyzed the anticancer activity of5-FU in the 5-FU-resistant HCT116RF10 cells and parentalHCT116 cells transfected with TYMS-targeted siRNA.HCT116 and HCT116RF10 cells were treated with the indicatedconcentration of 5-FU (EC20 values: 3 μM for HCT116cells; 15 μM for HCT116RF10 cells), respectively.Additionally, the knockdown of TYMS enhanced theanticancer activity of 5-FU in both types of CRC cells (Figure 2A–C).