Induction of ER-stress in cervical carcinoma cells (HeLa) by glucose deprivation showed early upregulation of ATF4 (Fig. 1e) and other target genes of this stress response pathway such as DDIT3, GADD34, ATF3, and EIF4EBP1 at 24 h. This evidence concerns the gene PPP1R15A and cervical carcinoma.