Objective To investigate the effect of ALOX 15 on ferroptosis in BGC823 cells.Methods BGC823 cell lines with ALOX 15 overexpression or ALOX 15 interference were established,and the transfection efficiency was verified by quantitative real-time PCR and Western Blot.The proliferation of BGC823 cells overexpressing ALOX 15 or interfering with ALOX 15 expression was detected by CCK-8 method.The levels of ferrous ion(Fe2+),reactive oxygen species(ROS),malondialdehyde(MDA)and glutathione(GSH)in each group were determined by using kits.The protein level of glutathione peroxidase 4(GPX4)in each group was detected by Western Blot.Results BGC823 cell lines overexpressing ALOX 15 or interfering with ALOX15 expression were successfully constructed.The cell proliferation rate at 24,48 h,GSH level and GPX4 expression level of pcDNA3.1-ALOX15 group were lower than those of pcDNA3.1 group and Control group,while ROS level,MDA level,Fe2+level,ALOX15 mRNA and protein level were higher than those of pcDNA3.1 group and Control group,and the differences were statistically significant(P<0.05).After transfection of si-ALOX15,the cell proliferation rate at 24,48 h and the expression of GSH level and GPX4 level in BGC823 cells in si-ALOX 15 group were higher than those in si-NC group,and ROS level,MDA level,Fe2+level,ALOX15 mRNA and protein were lower than those in si-NC group,the differences were statistically significant(P<0.05).Conclusion Up-regulation of ALOX15 protein expression promotes ferroptosis in gastric cancer cells.