In the present study, we focused on KRT13 as a candidate radioresistance gene because certain keratins (KRTs) are reportedly shown to have cancer stem-like properties, including KRT19 in hepatocellular carcinoma and colorectal cancer, KRT6 in lung cancer and KRT17 in cervical cancer [26–28, 34]. This evidence concerns the gene KRT17 and colorectal cancer.