WARS1 and glioblastoma: LN229 and G55 cells utilize the ATF4 pro-survival function upon hypoxia and ER stress induction, as well as TMZ treatment, through inducing gene expression of exportin-T (XPOT), tryptophanyl-tRNA synthetase 1 (WARS1), and tribbles homolog 3 (TRIB3), providing resistant properties to GBM tumors [136].