PPP1R15A and colonic neoplasm: As Nrf2 involved in chemoresistance is promoted by PERK in HT29 colon cancer cells (Salaroglio et al., 2017), researchers attached the importance of PERK and CHOP to GADD34 dephosphorylating eIF2α, providing an insight that suppression of the CHOP-GADD34 axis may be a tumor survival mechanism (Clarke et al., 2014).