Ketamine Induces Ferroptosis of Liver Cancer Cells by Targeting lncRNA PVT1/miR-214-3p/GPX4

Background: Liver cancer ranks the top four malignant cancer type worldwide, which needs effective and safe treatment. Ferroptosis is a novel form of regulated cell death driven by iron-dependent lipid peroxidation and has been regarded as a promising therapeutic target for cancers. In this work, we aimed to study the effects of anesthetic ketamine on proliferation and ferroptosis of liver cancer. Methods: Cell viability and proliferation were detected by cell counting kit 8 (CCK-8), colony formation, and 5-ethynyl-2′-deoxyuridine (EdU) assay. Ferroptosis was determined by levels of Fe 2+ , lipid reactive oxygen species (ROS), and malondialdehyde (MDA). RNA levels of lncPVT1, miR-214-3p, and glutathione peroxidase 4 (GPX4) were checked by real-time PCR assay. Clinical liver tumor samples were collected to detect the levels of long noncoding RNA lncPVT1, miR-214-3p, and GPX4, and their correlation was evaluated by Pearson comparison test. Luciferase reporter gene assay and RNA pulldown were conducted to determine the binding between lncPVT1, miR-214-3p, and GPX4 3ʹUTR. Results: Ketamine significantly suppressed viability and proliferation of liver cancer cells both in vitro and in vivo, as well as stimulated ferroptosis, along with decreased expression of lncPVT1 and GPX4. LncPVT1 directly interacted with miR-214-3p to impede its role as a sponge of GPX4. Depletion of lncPVT1 accelerated the ferroptosis of live cancer cells, whereas miR-214-3p inhibition and GPX4 overexpression reversed this effect. Ketamine-induced cell growth suppression and ferroptosis were also suppressed by miR-214-3p inhibition and GPX4 overexpression. Conclusion: In this work, we determined that ketamine suppressed viability of liver cancer cells and induced ferroptosis and identified the possible regulatory mechanism of lncPVT1/miR-214-3p/GPX4 axis. Keywords: liver cancer, ketamine, lncPVT1, miR-214-3p, GPX4