H1299 lung cancer cells with exogenous R175H mutant TP53 had a lower basal concentration of total GSH + GSSG as compared to parental p53 null H1299 cells or doxycycline‐treated H1299 tet‐off R175H cells (Fig 5C, and Appendix Fig S5A and B). Here, TP53 is linked to lung cancer.