p53 Promoted Ferroptosis in Ovarian Cancer Cells Treated with Human Serum Incubated-Superparamagnetic Iron Oxides

Yunhan Zhang,1,* Meihui Xia,2,* Zizhen Zhou,3 Xiaoqing Hu,1 Jiabin Wang,1 Meiyu Zhang,3 Yi Li,4 Liankun Sun,1 Fangfang Chen,4,5 Huimei Yu1,6 1Key Laboratory of Pathobiology, Ministry of Education, Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun 130021, People’s Republic of China; 2Department of Obstetrics & Gynecology, The First Hospital of Jilin University, Changchun, Jilin 130021, People’s Republic of China; 3Clinical Medical College, Jilin University, Changchun 130021, People’s Republic of China; 4State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, Jilin 130012, People’s Republic of China; 5Department of Gastrointestinal, Colorectal and Anal Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, People’s Republic of China; 6Animal Experiment Center, College of Basic Medical Sciences, Jilin University, Changchun 130021, People’s Republic of China*These authors contributed equally to this workCorrespondence: Huimei YuKey Laboratory of Pathobiology, Ministry of Education, Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun 130021, People’s Republic of ChinaTel +86 431 85619485Email yuhuimei@jlu.edu.cnFangfang ChenDepartment of Gastrointestinal, Colorectal and Anal Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin 130033, People’s Republic of ChinaTel +86 431 84995312Email cff@jlu.edu.cnMethods: In this study, we used MTT assays to demonstrate that a combination of SPIO-Serum and wild-type p53 overexpression can reduce ovarian cancer cell viability in vitro. Prussian blue staining and iron assays were used to determine changes in intracellular iron concentration following SPIO-Serum treatment. TEM was used to evaluate any mitochondrial damage induced by SPIO-Serum treatment, and Western blot was used to evaluate the expression of the iron transporter and lipid peroxidation regulator proteins. JC-1 was used to measure mitochondrial membrane potential, and ROS levels were estimated by flow cytometry. Finally, xCT protein expression and mitochondrial ROS levels were confirmed using fluorescence microscopy.Results: SPIO-Serum effectively induced lipid peroxidation and generated abundant toxic ROS. It also facilitated the downregulation of GPX4 and xCT, ultimately resulting in iron-dependent oxidative death. These effects could be reversed by iron chelator DFO and lipid peroxidation inhibitor Fer-1. SPIO-Serum treatment disrupted intracellular iron homeostasis by regulating iron uptake and the cells presented with missing mitochondrial cristae and ruptured outer mitochondrial membranes. Moreover, we were able to show that p53 contributed to SPIO-Serum-induced ferroptosis in ovarian cancer cells.Conclusion: SPIO-Serum induced ferroptosis and overexpressed p53 contributed to ferroptosis in ovarian cancer cells. Our data provide a theoretical basis for ferroptosis as a novel cell death phenotype induced by nanomaterials.Keywords: ferroptosis, SPIO, p53, TF, xCT, iron-based nanomaterials