Since tRNASer(AGA) upregulation increased levels of transcription factor ATF4 activation, it is likely that genes relevant for adaptation under stressful conditions like the ones imposed by tumor microenvironment (hypoxia, oxidative stress and nutrient deprivation) may be upregulated, besides GADD34 transcription, (Fels and Koumenis, 2006; Lewerenz and Maher, 2009; Ye et al., 2010). This evidence concerns the gene PPP1R15A and neoplasm.