To confirm the effects of ERCC1 expression on CCRT efficacy, we induced ERCC1 overexpression in colorectal cancer cells and in an ectopic carcinoma animal model prior to radiation exposure, and we found evidence that ERCC1 overexpression triggered resistance to radiotherapy (Figure 2, Figure 3, Figure 4 and Figure 5). The gene discussed is ERCC1; the disease is colorectal cancer.