Since the expression of the DC maturation markers CD80 and CD86 mRNA was higher in ARID1A-silenced CRC cells following RT treatment, and the combination of RT with a CHK1 inhibitor further increased type I IFN-related gene expression in ARID1A-silenced CRC cells, we next evaluated whether targeting CHK1 can improve antitumor immune responses in vivo. Here, ARID1A is linked to colorectal carcinoma.