By treating GC cell lines with exogenous ROS and lipid ROS, we confirmed that ROS accumulation induced by targeting or knocking down GPx4 suppresses peritoneal metastasis by promoting RCC2 ubiquitination and degradation through Aurora A-induced phosphorylation of RCC2 both in vitro and vivo. Phosphorylation can influence protein ubiquitination by affecting E3 ligase recognition or the subcellular localization of substrates. This evidence concerns the gene GPX4 and gastric cancer.