Cannell et al. found that the phosphorylated HNRNP A0 at Ser84 activated by MAPKAPK-2 showed more apparent cytoplasmic localization compared to the non-phosphorylated HNRNP A0 in lung cancer, and increased the stability of mRNA p27/growth arrest and DNA damage-inducible α (p27/Gadd45α) when DNA was impaired. Here, HNRNPA0 is linked to lung carcinoma.