[HTML][HTML] Fin56-induced ferroptosis is supported by autophagy-mediated GPX4 degradation and functions synergistically with mTOR inhibition to kill bladder cancer …

Y Sun, N Berleth, W Wu, D Schlütermann… - Cell death & …, 2021 - nature.com
Y Sun, N Berleth, W Wu, D Schlütermann, J Deitersen, F Stuhldreier, L Berning, A Friedrich…
Cell death & disease, 2021nature.com
Ferroptosis is a form of regulated cell death that emerges to be relevant for therapy-resistant
and dedifferentiating cancers. Although several lines of evidence suggest that ferroptosis is
a type of autophagy-dependent cell death, the underlying molecular mechanisms remain
unclear. Fin56, a type 3 ferroptosis inducer, triggers ferroptosis by promoting glutathione
peroxidase 4 (GPX4) protein degradation via a not fully understood pathway. Here, we
determined that Fin56 induces ferroptosis and autophagy in bladder cancer cells and that …
Abstract
Ferroptosis is a form of regulated cell death that emerges to be relevant for therapy-resistant and dedifferentiating cancers. Although several lines of evidence suggest that ferroptosis is a type of autophagy-dependent cell death, the underlying molecular mechanisms remain unclear. Fin56, a type 3 ferroptosis inducer, triggers ferroptosis by promoting glutathione peroxidase 4 (GPX4) protein degradation via a not fully understood pathway. Here, we determined that Fin56 induces ferroptosis and autophagy in bladder cancer cells and that Fin56-triggered ferroptosis mechanistically depends on the autophagic machinery. Furthermore, we found that autophagy inhibition at different stages attenuates Fin56-induced oxidative stress and GPX4 degradation. Moreover, we investigated the effects of Fin56 in combination with Torin 2, a potent mTOR inhibitor used to activate autophagy, on cell viability. We found that Fin56 synergizes with Torin 2 in cytotoxicity against bladder cancer cells. Collectively, our findings not only support the concept that ferroptosis is a type of autophagy-dependent cell death but imply that the combined application of ferroptosis inducers and mTOR inhibitors is a promising approach to improve therapeutic options in the treatment of bladder cancer.
nature.com