Our present study showed that the activation of Akt by hPEBP4 in rectal cancer cells on irradiation was abolished after antioxidant was given to inhibit the production of ROS, but hPEBP4 had no effect on the intracellular level of ROS, suggesting that hPEBP4 specifically promotes the activation of Akt by ROS after irradiation in rectal cancer cells. Here, PEBP4 is linked to rectal cancer.