ATF3 and neoplasm: Ginsenoside Rh4 induces ferroptosis by inhibiting the <i>KEAP1</i>/<i>NRF2</i>/<i>HO-1</i> pathway and remodeling the gut microbiota to increase butyrate levels, which synergistically enhance tumor cell ferroptosis sensitivity through <i>ATF3</i> activation and suppression of <i>GPX4</i>.