Fig. 1

PREX2 acts as a radioresistant gene in CRC. A, B heat maps and volcanic maps showed significant differential genes after RNA-seq screening between IR-resistant cell line IR-SW480 and IR-sensitive cell line SW480. C, D qRT-PCR and Western blot analysis were conducted to determine the expression of PREX2 in IR-SW480 and SW480. E The analysis of PREX2 expression in radiotherapy-resistant CRCs compared with radiotherapy-sensitive CRCs in CRC microarray profile (GES145037 responder: 0.674 ± 0.109, non-responder: 0.784 ± 0.096, p = 0.0084; GSE1150082 responder: − 0.261 ± 0.125, non-responder: 0.180 ± 0.143, p = 0.0345). F RSI was calculated using the data from the TCGA database and the expression of PREX2 in the low RSI group and high RSI group was analyzed. G Kaplan–Meier analysis of progression-free interval in all patients with CRC according to PREX2 expression in TCGA dataset (log-rank test p < 0.001). H The expressions of PREX2 protein in specimens, including 54 CRC tissue specimens, were examined by IHC. Representative IHC images (left) and correlation analysis (right) were shown. Scale bar: 50 μm. *p < 0.05, **p < 0.01, ***p < 0.001