RESUMEN
Objective:To investigate the effect of circ_DCAF6 on the proliferation,migration and apoptosis of colorectal cancer cells resistant to cisplatin(DDP)and its possible mechanism.Methods:SW480 and DDP-resistant cells SW480/DDP were cultured in vitro.The expression of circ_DCAF6 and miR-485-3p in the cells was detected by RT-qPCR,and the expression of FOXK1 protein was detected by Western blotting.After si-NC,si-circ_DCAF6,miR-NC,or miR-485-3p was transfected into SW480/DDP cells,or si-circ_DCAF6 and anti-miR-485-3p were co-trans-fected into SW480/DDP cells,respectively,CCK-8 method was used to detect the effect of DDP at different concentrations(0,0.156,0.625,2.5,10,40,160 p g/mL)on the 24 h survival rate of trans-fected cells,and the half inhibitory concentration(IC50 value)was calculated;Cell migration and apoptosis were detected and the regulatory relationship between circ_DCAF6,miR-485-3p and FOXK1 was verified.Results:Compared with SW480 cells,circ_DCAF6 and FOXK1 protein ex-pressions were increased in SW480/DDP cells,while miR-485-3p expression was decreased(P＜0.05).Silencing circ_DCAF6 or overexpression of miR-485-3p inhibited the proliferation and mi-gration of SW480/DDP cells and the expression of FOXK1 protein,increased the sensitivity of SW480/DDP cells to DDP,and promoted cell apoptosis(P＜0.05).Knockdown of miR-485-3p atten-uated the effects of circ_DCAF6 silencing on the malignant phenotype of SW480/DDP cells.circ_DCAF6 could target miR-485-3p;FOXK1 was the target gene of miR-485-3p.Conclusion:Silencing circ_DCAF6 could inhibit the proliferation and migration of SW480/DDP cells and promote cell apoptosis.Its mechanism of action is related to the regulation of miR-485-3p/FOXK1 axis.