GPX4 and cancer: Fe3O4@aC caused a decrease in reactive oxygen species(ROS) production and an increase in the levels of antioxidant proteinsFOXO3a, SOD1, and GPX4 that was accompanied by elevated levels ofcell cycle inhibitors (p21, p27, and p57), proinflammatory (NFκB,IL-6, and IL-8) and autophagic (BECN1, LC3B) markers, nucleolar stress,and subsequent apoptotic cell death in etoposide-stimulated senescentbreast cancer cells.