放疗调控circRNA ACAP2/miR-1-3p/CENPF轴对结直肠癌细胞铁死亡的影响OA

Objective To investigate the effect of abnormal expression of circRNA ACAP2(ACAP2)regulated by radiotherapy on ferroptosis of colorectal cancer.Methods RT-qPCR was used to detect the expression of ACAP2 in normal human colon mucosal epithelial NCM460 cells,and colorectal cancer cell HCT116,DLD-1,SW620,and SW480 cells.SW620 cells and SW480 cells were divided into Control group,4Gy+NC group,and 4Gy+ACAP2 OE group,The CCK-8,Flow cytometry,and Transwell assays were used to detect the prolifera-tion,apoptosis,migration,and invasion ability.Flow cytometry and Mito-tracker Red staining were used to de-tect Reactive Oxygen Species(ROS)and mitochondrial damage.The reagent kits were used to detect the con-centrations of Cysteine(Cys),Glutathione peroxidase 4(GPX4),Iron,and Malondialdehyde(MDA).West-ern blot was used to detect the protein expression of GXP1,FTH1,and SLC7A11.The dual luciferase reporter assay validated the targeting relationship between ACAP2,miR-1-3p,and CENPF.Results The expression of ACAP2 was higher in HCT116,DLD-1,SW620,and SW480 cells than in NCM460 cells(P＜0.05).Com-pared with the Control group,the proliferation,migration,invasion of SW620 cells and SW480 cells in the 4Gy+NC group were significantly reduced(P＜0.05),and the protein expression of GXP1,FTH1,and SLC7A11 were significantly downregulated(P＜0.05),the concentrations of Cys and GPX4 were significantly reduced(P＜0.05),and cell apoptosis,mitochondrial damage,Iron and MDA concentration were significantly in-creased(P＜0.05).Compared with the 4Gy+NC group,the proliferation,migration,invasion of SW620 cells and SW480 cells in the 4Gy+ACAP2 OE group were significantly increased(P＜0.05),the expression of GXP1,FTH1,and SLC7A11 proteins was significantly upregulated(P＜0.05),the concentrations of Cys and GPX4 were significantly increased(P＜0.05),and the cell apoptosis,mitochondrial damage,Iron and MDA concentration were significantly reduced(P＜0.05).The dual luciferase reporter assay showed that miR-1-3p is the target gene of ACAP2,and CENPF is the target gene of miR-1-3p.The expression levels of GPX4,FTH1,and SLC7A11 in SW620 and SW480 cells in the 4Gy+ACAP2 OE+si-CENPF group were significantly lower than those in the 4Gy+ACAP2 OE group(P＜0.05).the concentrations of Cys and GPX4 were significantly lower than those in the 4Gy+ACAP2 OE group(P＜0.05),and the Iron and MDA concentration were signifi-cantly higher than those in the 4Gy+ACAP2 OE group(P＜0.05).Conclusion Radiotherapy can downregulate ACAP2 expression to inhibit miR-1-3p/CENPF signaling axis and induce ferroptosis of colorectal cancer cells.