Although ARF can suppress tumor growth by activating p53 function, the mechanisms by which it suppresses tumor growth independently of p53 are not well understood. Here, we identified ARF as a key regulator of nuclear factor E2-related factor 2 (NRF2) through complex purification. ARF inhibits the ability of NRF2 to transcriptionally activate its target genes, including SLC7A11, a component of the cystine/glutamate antiporter that regulates reactive oxygen species (ROS)-induced ferroptosis. As a consequence, ARF expression sensitizes cells to ferroptosis in a p53-independent manner while ARF depletion induces NRF2 activation and promotes cancer cell survival in response to oxidative stress. Moreover, the ability of ARF to induce p53-independent tumor growth suppression in mouse xenograft models is significantly abrogated upon NRF2 overexpression. These results demonstrate that NRF2 is a major target of p53-independent tumor suppression by ARF and also suggest that the ARF-NRF2 interaction acts as a new checkpoint for oxidative stress responses. Chen et al. identified ARF as a key regulator of NRF2-mediated activation of SLC7A11, a component of the cystine/glutamate antiporter that regulates reactive oxygen species (ROS)-induced ferroptosis. They showed that the ARF-NRF2 interaction is critical for p53-independent ferroptosis and tumor suppression induced by ARF.
Bibliographical noteFunding Information:
We thank Dr. Donna Zhang and Dr. Jason Weber for providing critical reagents for this study. This work was supported by the National Cancer Institute of the NIH under awards 5R01CA169246 , 5RO1CA190477 , 5RO1CA085533 , and 5RO1CA216884 to W.G, and 5R01-CA172272 to R.B. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
- oxidative stress
- transcriptional regulation