ATF4 and lung cancer: 6G suppressed the growth of lung cancer cells by inhibiting USP14 expression, leading to a significant increase in the number of autophagosomes, ROS levels, and iron concentration, as well as regulating downstream autophagy-dependent ferroptosis-related proteins including nuclear receptor coactivator 4 (NCOA4), FTH1, TfR1, GPX4, and activating transcription factor 4 (ATF4) (120).