For example, in several cancer cell lines susceptible to ferroptosis and lacking significant expression of LOXs, genetic POR depletion prevented ferroptosis triggered by class 1 (xCT inhibitors) and class 2 (GPX4 inhibitors) inducers, probably by preventing the cycling between Fe(II) and Fe(III) in the heme component of P450s (Zou et al. 2020). Here, GPX4 is linked to cancer.