ATF4 and glioblastoma: Upon transfecting miR-320a mimic in cells with low endogenous miR-320a, such as glioblastoma T98G cells, HeLa cells and mouse embryonic fibroblast (MEF) cells, Tg-induced ATF4 activation was further elevated (Figs 5D, S10B and S10C, compare lane 3s to lane 4s).